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Hydrol Earth Syst Sci 17 2247ndash2262 2013wwwhydrol-earth-syst-scinet1722472013doi105194hess-17-2247-2013copy Author(s) 2013 CC Attribution 30 License
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Potential effects of climate change oninundation patterns in the Amazon Basin
F Langerwisch1 S Rost1 D Gerten1 B Poulter2 A Rammig1 and W Cramer3
1Earth System Analysis Potsdam Institute for Climate Impact Research (PIK) PO Box 60 12 03 Telegraphenberg A6214412 Potsdam Germany2Laboratoire des Sciences du Climat et de lrsquoEnvironnement UMR8212 CNRS ndash CEA UVSQ Gif-sur Yvette France3Institut Mediterraneen de Biodiversite et drsquoEcologie marine et continentale (IMBE) Aix-Marseille UniversityCNRSBatiment Villemin Europole de lrsquoArbois ndash BP 80 13545 Aix-en-Provence cedex 04 France
Correspondence toF Langerwisch (fannylangerwischpik-potsdamde)
Received 16 December 2011 ndash Published in Hydrol Earth Syst Sci Discuss 6 January 2012Revised 8 March 2013 ndash Accepted 1 May 2013 ndash Published 20 June 2013
Abstract Floodplain forests namely the Varzea and Igapocover an area of more than 97 000 km2 A key factor for theirfunction and diversity is annual flooding Increasing air tem-perature and higher precipitation variability caused by cli-mate change are expected to shift the flooding regime duringthis century and thereby impact floodplain ecosystems theirbiodiversity and riverine ecosystem services To assess theeffects of climate change on the flooding regime we use theDynamic Global Vegetation and Hydrology Model LPJmLenhanced by a scheme that realistically simulates monthlyflooded area Simulation results of discharge and inundationunder contemporary conditions compare well against site-level measurements and observations The changes of calcu-lated inundation duration and area under climate change pro-jections from 24 IPCC AR4 climate models differ regionallytowards the end of the 21st century In all 70 of the 24 cli-mate projections agree on an increase of flooded area in aboutone third of the basin Inundation duration increases dramat-ically by on average three months in western and around onemonth in eastern Amazonia The time of high- and low-waterpeak shifts by up to three months Additionally we find adecrease in the number of extremely dry years and in theprobability of the occurrence of three consecutive extremelydry years The total number of extremely wet years does notchange drastically but the probability of three consecutive ex-tremely wet years decreases by up to 30 in the east andincreases by up to 25 in the west These changes implicatesignificant shifts in regional vegetation and climate and willdramatically alter carbon and water cycles
1 Introduction
Amazonia plays a vital role for the global water and carboncycles through enormous water and carbon stores and fluxesThe Amazon catchment covers six million square kilometersand about 15 of the worldrsquos freshwater runoff is dischargedby the Amazon River (Gaillardet et al 1997) Dissolved inthis water about 33 Tg C yrminus1 are thought to be exported tothe Atlantic Ocean as organic carbon (Moreira-Turcq et al2003) A much larger amount approximately 470 Tg C yrminus1gasses out to the atmosphere as CO2 (Richey et al 2002)
Climate and land use change currently affect Amazonianforests substantially leading to a reduction of biomass biodi-versity and ecosystem services (Fearnside 2004 Foley et al2007 Nepstad et al 2007 Betts et al 2008) Since the forc-ing from changing climate and land use appears to be non-linearly related to the stability of the Amazonian ecosystem(Sitch et al 2008 Nobre and De Simone Borma 2009) thisregion has been identified as one of a set of global ldquotippingelementsrdquo particularly susceptible to global change (Lentonet al 2008)
Much of central Amazonia is influenced by annual flood-ing predominantly caused by precipitation across the basinDuring the flooding season between January and March (Fo-ley et al 2002) the water rises with an amplitude of 5 to 15 m(Junk 1985) and an average speed of 005 m dminus1 (Junk andPiedade 1997) The extent of flooded area in central Ama-zonia increases from about 4 during low water to 16 during high water stage (Richey et al 2002) The recur-rent change between the terrestrial and aquatic phase forms
Published by Copernicus Publications on behalf of the European Geosciences Union
2248 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
characteristic and very diverse habitats for millions of plantand animal species which are intimately related to the recur-rent annual flooding These floodplains are alternately suit-able for aquatic and terrestrial organisms The distributionof these species is especially influenced by the duration ofthe aquatic and terrestrial phase (Junk and Piedade 1997)Floodplain forests cover approximately 97 000 km2 (Parolinet al 2004) and contain about 20 of the Amazonian treespecies (Naiman et al 2005) The vast floodplain areas thusrepresent one of the riches biota on earth providing severalecosystem services such as timber and fish production andcarbon storage (Keddy et al 2009)
Climate change is expected to alter temperature and pre-cipitation patterns which can potentially lead to changes inflood regime such as a reduction in discharge in the Ama-zon River (Arora and Boer 2001) The variability in precip-itation is expected to increase (Seneviratne et al 2012) andmay cause higher spatial and temporal variability in river dis-charge and flooded area (Coe et al 2002) The effect of cli-mate change on the El Nino Southern Oscillation (ENSO) re-mains unclear (Malhi and Wright 2004) but ENSO changesdischarge drastically (Foley et al 2002) Changes in timeduration and height of the flooding has the potential to shiftvegetation distribution which may in turn lead to feedbacksto the atmosphere (eg Cox et al 2004 Malhi et al 2008)
To assess the effects of potential changes in precipita-tion and temperature on discharge and freshwater ecosystemservices usually hydrological models are applied (Vigerstoland Aukema 2011) which are for example WaterGAP (Al-camo et al 2000 Doll and Zhang 2010 Doll et al 2003)WBM (Fekete et al 1999) and SWAT (Arnold and Fohrer2005) and VIC (Liang and Xie 2001 Liang et al 1994)A disadvantage of these models is that they do not incor-porate explicit simulation of vegetation dynamics which arean essential part of the water cycle We use the dynamicglobal vegetation and hydrology model LPJmL (Bondeau etal 2007 Gerten et al 2004 Rost et al 2008 Sitch et al2003) which has been improved for regional application tothe Amazon Basin and includes the dynamic and spatially ex-plicit reproduction of the specific hydrological patterns of themain river stem and its tributaries These patterns consist ofseasonal discharge time and duration of lowhigh water peri-ods and the changing extent of the flooded area during thoseperiods LPJmL combines dynamic terrestrial vegetation de-velopment with carbon and water cycles This enables us toestimate not only the direct effect of changing precipitationand temperature on discharge but also to include the indirecteffects of these changes on vegetation cover and type whichin turn alters runoff and discharge
The main goal of our study is thus to understand and quan-tify the magnitude of impacts of future climate change onthe Amazonian inundation patterns We provide estimates onclimate change induced shifts of inundation patterns whichcomprises of time and duration of lowhigh water periodsand the changing extent of the flooded area during those pe-
riods We describe here a method to calculate monthly in-undated area We evaluate our simulated results against ob-served data for discharge and potentially floodable area andestimate changes in inundation patterns in Amazonia Toquantify the amplitude of shifts in the flooding regime dueto climate change we use forcing data of the 24 General Cir-culation Models (GCMs) from the 4th Assessment Reportof the Intergovernmental Panel on Climate Change (IPCC2007 Randall et al 2007)
2 Methods
We apply the Dynamic Global Vegetation and HydrologyModel LPJmL (Sitch et al 2003 Gerten et al 2004 Bon-deau et al 2007 Rost et al 2008) to understand and to as-sess the effect of climate change on current Amazonian inun-dation patterns LPJmL computes establishment abundancevegetation dynamics growth and productivity of the worldrsquosmajor plant functional types as well as the associated carbonand water fluxes The model is typically applied on a gridof 05
times 05 longitudelatitude and at daily time steps Car-bon fluxes and vegetation dynamics are directly coupled towater fluxes Modelled soil moisture runoff and evapotran-spiration were found to reproduce observed patterns well andtheir quality is comparable to stand-alone global hydrologi-cal models (Wagner et al 2003 Gerten et al 2004 2008Gordon et al 2004 Biemans et al 2009)
The river routing module of LPJmL (described by Rost etal 2008) assumes a surface water storage pool for each gridcell representing the water storage and retention in reservoirsand lakes The change of water storage in the river over timeis represented as the runoff generated in the cell the input ofdischarge accumulated from upstream grid cells the outputto the downstream cell and the outflow of lakes in the respec-tive cell The output to the downstream cell is determinedas a linear transport of discharge depending on the routingvelocity (v) and the distance between the midpoints of theconnected cells Earlier versions of LPJmL used a globallyhomogeneous routing velocity of 1 msminus1 (Rost et al 2008)which had difficulties to reproduce the Amazonian hydro-graph with shifts within the hydrograph of several monthsIn a former study we already improved the reproduction ofthe hydrograph by applying a homogeneously reduced rout-ing velocity of 025 msminus1 to the Amazon Basin leading tosubstantial reductions of the shift for several observation sites(Langerwisch et al 2008) Our new approach is to use het-erogeneous routing velocities which take topographic differ-ences within the Amazon catchment into account for furtherimprovement of the hydrograph
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2249
Table 1Slope classes
Slope range Class
le 15 5gt 15ndashle 3 4gt 3ndashle 6 3gt 6ndashle 10 2gt 10ndashle 35 1gt 35 0
Table 2Relative slope position classes
Distance range Class
0ndash10 cells 2211ndash20 cells 1921ndash40 cells 1341ndash60 cells 1261ndash80 cells 11gt 81 cells 10
21 Calculation of routing velocity and potentialfloodable area
We extend on earlier work (Langerwisch et al 2008) andtake topography into account by calculating cell specificrouting velocities which are comparable to river flow veloc-ities In the model the routing velocity is used to calculatethe distance that runoff water can move within a time step(see also Rost et al 2008) We also estimate the extent ofpotential floodable area and monthly flooded area
We use a digital elevation model (DEM) provided by theWWF database HydroSHEDS (WWF HydroSHEDS 2007)at a resolution of 15 arc seconds longitudelatitude corre-sponding to approximately 460 m edge length in the study re-gion to calculate the routing velocity and the floodable areaWe apply grid-based elevation data (instead of elevation dataof the actual gauging stations) to obtain a continuous spa-tially consistent basis for our calculations The DEM eleva-tion represents the top of the canopy which issim 30 m lowerthan the actual ground elevation (Anderson et al 2009) Forthe Amazon Basin we assume this to be a systematic er-ror in the DEM elevation and use it directly for calculatingthe routing velocity The calculations of the routing veloc-ity were conducted applying well-established techniques (fordetails see Supplement S1 and S2) The data were processedat the original resolution of HydroSHEDS Final results arere-sampled at 05 times 05 (longitudelatitude) resolution
211 Routing velocity
Based on the DEM we calculate the cellrsquos slope and the cor-responding routing velocity (details see Supplement S1 andS2) The calculation of the high resolution slopeS [degree] is
Table 3Landform types with corresponding slope and mTRMI
Landform type Slope range mTRMI
valley flats lt 3 gt 22nearly level terraces lt 3
le 22gently sloping toe slopes and bottoms ge 3ndashlt 10 gt 18gently sloping ridges ge 3ndashlt 10
le 18very moist steep slopes ge 10ndashle 35
ge 18moderately moist steep slopes ge 10ndashle 35 11ndash17dry steep slopes ge 10ndashle 35 lt 10
based on the work of Burrough (1986) We apply the medianof all subcell values to aggregate the high resolution slope toa 05times 05 cell slope Subsequently we calculate slope de-pendent routing velocityv [msminus1] (Eq 1 Fig S1) based onthe ManningndashStrickler formulation
v =
(tan
(S times
π
180
)) 12times k times R
23 (1)
wherek is the ManningndashStrickler coefficient [m13 sminus1] de-scribing the roughness of the area For natural rivers thisvalue ranges between 28 and 40 m13 sminus1 (Patt 2001) Dueto the lack of detailed cell specific information we setk =
35 m13 sminus1 R is the hydraulic radius [m] It describes theratio between the cross-sectional area [m2] and the wettedperimeter [m] of the channel In wide and shallow watersit corresponds to the depth of the water It is higher in nar-row and deep river sections and lower in wide shallow riversections but cell specific information forR are not avail-able therefore we neglect the influence of this factor and setR = 10 m The median of the calculated routing velocity is025 msminus1 We included an analysis to estimate the sensitiv-ity of the calculated routing velocity tok andR We variedk between 28 and 40 m13 sminus1 (with a constantR = 10 m)which lead to median routing velocities between 020 msminus1
(minus200 ) and 029 msminus1 (+16 ) We variedR between 02and 12 m (with a constantk = 35 m13 sminus1) which lead tomedian routing velocities between 009 msminus1 (minus64 ) and029 msminus1 (+169 ) Additionally we tested all possiblekandR combinations in the range given above (see Fig S2)
212 Floodable area
As a basis for the calculation of inundation we first estimatethe potentially floodable area by applying the same DEMused for the routing velocity calculation (see Sect 211)We determine a modified Topographic Relative Moisture In-dex (mTRMI) based on the work of Parker (1982) on thenative resolution of the DEM (15 arc seconds) This indexis applied to classify structural landscape conditions whichcan be arranged in 7 different landform types such asvalleyflatsanddry steep slopes(also see Tables 1ndash3) It uses sev-eral weighted geomorphologic characteristics such as slopeslope steepness slope configuration relative slope position
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2250 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Table 4 List of the 24 IPCC coupled general circulation models(GCMs) used in this study Details for the climate models see IPCC2007 AR4 chapter 8 (Randall et al 2007)
Model name
BCCR ndash BCM 20 INGV ndash SXGCCCMA ndash CGCM 31 (T47) INM ndash CM 30CCCMA ndash CGCM 31 (T63) IPSL ndash CM 4CNRM ndash CM 3 MIROC 32 (hires)CSIRO ndash Mk 30 MIROC 32 (medres)CSIRO ndash Mk 35 MIUB ndash ECHO-GGFDL ndash CM 20 MPI ndash ECHAM 5GFDL ndash CM 21 MRI ndash CGCM 232aGISS ndash AOM NCAR ndash CCSM 3GISS ndash EH NCAR ndash PCM 1GISS ndash ER UKMO ndash HadCM 3FGOALS ndash g 10 UKMO ndash HadGEM 1
Fig 1 Simulated mean discharge [log m3 sminus1] during June aver-aged over the reference period 1961ndash1990 The white crosses indi-cate the exaple sites Cruzeiro do Sul (CdS ID 3) Porto Velho (PVID 41) andObidos (Obi ID 10 and 42)
and aspect which can be calculated from the DEM We usethe resulting landform type valley flats as potentially flood-able area
In our study mTRMI is the sum of classified slope classi-fied slope configuration and classified relative slope position(Eq 2 see below for definitions)
mTRMI = Sclass+ Sconfigclass+ Sposclass
(2)
We neglect aspect because differences between north andsouth facing slopes are insignificant in the tropics (compareto Donnegan et al 2007) A detailed description of the calcu-lation of mTRMI summands can be found in the Supplement
The first summand is classified slope (Eq 2Sclass) Weuse the previously calculated slope values and slice them insix slope classes (Table 1)
38
823
Figure 2 The 44 sites used for comparison of observed and simulated discharge 824
825
Fig 2The 44 sites used for comparison of observed and simulateddischarge
The second summand is classified slope configuration(Eq 2Sconfclass) Slope configuration describes the convex-ity or concavity of the land surrounding any grid cell basedon the change in elevationZ [m] from cellij to all cells lo-cated at the edge of the 5times 5 cell window We slice the fullrange of resulting values equally into 10 parts and assignthese parts into 3 slope configuration classes slices 0ndash4 toclassminus1 (convex topography) slice 5 to class 0 (flat topog-raphy) slices 6ndash10 to class 1 (concave topography)
The third summand is relative slope position (Eq 2Sposclass
) describing the distance of the cellij to the closestridges and streams We assign the distance [cells] to 6 relativeslope position classes (Table 2)
From the slope classes (Eqs S1ndashS3) the slope configu-ration classes (Eqs S5ndashS9) and the relative slope positionclasses (Eqs S10ndashS11) we calculate mTRMI (Eq 2) Wesum up classified slope (0 to 5) classified slope configura-tion (minus1 to 1) and classified relative slope position (10 to22) The mTRMI ranges from dry to wet (9 to 28) describingsite conditions
We generate a map (15 arc seconds resolution) of landformtypes by combining slopeS and mTRMI For this purpose wegroup sites with defined mTRMI and slope to certain land-form types (details in Table 3) Finally we use the landformtype valley flat which is potentially floodable area to cal-culate the fraction [] of floodable area for each 05times 05
grid cellWe then calculate the fraction of continuously flooded area
from the potentially floodable area (per 05times 05 cell) fromthe work of Richey et al (2002) They estimated that duringlow water stage about 4 and during high water stage about16 of a 177 million km2 quadrant of the central Ama-zon Basin is covered with water This means that 25 of
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2251
Tabl
e5
Com
paris
onof
obse
rved
and
sim
ulat
eddi
scha
rge
for
the
obse
rvat
ion
perio
d(s
eeal
soF
igs
3an
d4)
Ind
ices
are
give
nfo
rth
est
anda
rdsi
mul
atio
n(s
td)
with
slop
ede
pend
ent
rout
ing
velo
city
and
orig
inal
setti
ng(1
0m
sminus
1)
with
hom
ogen
eous
rout
ing
velo
city
of1
0m
sminus
1in
brac
kets
IDS
tatio
nLa
titud
eLo
ngitu
deD
atab
ase
Num
ber
ofob
sye
ars
Obs
erve
dm
inan
nual
disc
harg
e[m
3sminus
1]
Obs
erve
dm
ean
annu
aldi
scha
rge
[m3
sminus1]
Obs
erve
dm
axan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
inan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
ean
annu
aldi
scha
rge
[m3
sminus1]
Sim
ulat
edm
axan
nual
disc
harg
e[m
3sminus
1]
Will
mot
trsquosin
dex
ofag
reem
ent1st
d(1
0m
sminus1)
Err
orof
Qua
lV2
std
(10
msminus
1)
N-R
MS
E3[
]st
d(1
0m
sminus1)
Nas
hndashS
utcl
iffe4
std
(10
msminus
1)
Pea
rson
corr
elat
ion
coef
ficie
nt5st
d(1
0m
sminus1)
1E
stira
odo
Rep
ouso
minus4
37minus
709
3A
NE
EL
1619
325
1847
4915
525
9272
700
870
(07
93)
100
3(0
367
)21
27
(27
75)
037
0(
minus0
073)
079
1(0
678
)2
Sao
Pau
lode
Oliv
enca
minus3
47minus
687
5A
NE
EL
2315
272
4644
278
410
4013
2627
055
717
060
3(0
590
)0
322
(09
56)
347
0(3
596
)minus
136
0(minus
153
5)0
801
(06
94)
3C
ruze
irodo
Sul
minus7
62minus
726
7A
NE
EL
2975
907
2992
2411
0644
890
880
(08
48)
026
3(0
998
)19
68
(22
75)
036
6(0
153
)0
839
(07
96)
4G
avia
ominus
483
minus66
75
AN
EE
L23
603
4732
9932
151
5683
1786
80
855
(07
54)
096
4(0
993
)29
05
(36
94)
013
1(
minus0
405)
082
6(0
652
)5
Aca
naui
minus1
8minus
665
5A
NE
EL
2329
0013
778
2553
329
5511
611
2588
20
693
(06
12)
099
1(0
953
)22
26
(25
51)
minus0
120
(minus0
471)
051
4(0
358
)6
Flo
riano
Pei
xoto
minus9
05minus
673
8A
NE
EL
3027
583
2062
881
335
790
835
(07
93)
024
5(0
974
)26
45
(30
32)
000
7(
minus0
305)
081
0(0
751
)7
Labr
eaminus
725
minus64
8A
NE
EL
3072
354
4411
739
101
6241
2279
90
867
(07
71)
099
3(0
991
)30
60
(40
14)
023
2(
minus0
321)
082
5(0
666
)8
Ser
rinha
minus0
45minus
648
3A
NE
EL
2035
9915
980
3043
434
8615
975
3567
60
910
(08
12)
029
1(1
002
)13
71
(20
37)
064
9(0
225
)0
832
(06
68)
9C
arac
arai
18
minus61
13
AN
EE
L30
244
2898
1117
816
3681
1739
60
868
(08
13)
100
1(0
995
)21
22
(25
95)
015
0(
minus0
271)
086
7(0
790
)10
Obi
dos
minus1
9minus
555
05A
NE
EL
2875
602
172
696
306
318
4275
814
783
429
433
40
873
(06
13)
099
6(0
995
)17
08
(30
76)
035
6(
minus1
090)
086
8(0
426
)11
Por
todo
sG
auch
osminus
116
5minus
572
3A
NE
EL
2233
376
217
021
1077
4248
054
7(0
501
)0
986
(09
45)
714
9(7
786
)minus8
188
(minus9
899)
073
8(0
663
)12
Cac
hoei
rao
minus11
75
minus55
77
AN
EE
L20
224
815
2287
214
4364
340
541
(05
00)
024
6(0
962
)68
39
(73
59)minus
894
9(minus
105
22)
078
3(0
716
)13
Inde
cominus
101
3minus
554
2A
NE
EL
2037
011
4834
650
685
3899
074
2(0
735
)0
304
(10
02)
240
5(2
450
)minus0
200
(minus0
245)
067
4(0
659
)14
Tre
sM
aria
sminus
763
minus57
88
AN
EE
L15
429
3759
1036
59
5801
2244
40
715
(06
60)
098
4(0
966
)44
81
(49
23)minus
202
1(minus
264
7)0
791
(06
93)
15Ja
toba
minus5
15minus
568
3A
NE
EL
2236
4910
790
2633
430
1448
948
219
077
6(0
729
)0
996
(09
89)
414
8(4
512
)minus
125
5(minus
166
9)0
872
(07
75)
16S
aoF
elix
doX
ingu
minus6
58minus
520
5A
NE
EL
2369
750
8821
660
979
6331
724
072
4(0
646
)0
324
(09
50)
295
7(3
340
)minus1
331
(minus1
974)
075
5(0
618
)17
Bel
oH
oriz
onte
minus5
38minus
528
8A
NE
EL
2275
952
3218
818
2085
4234
269
075
1(0
673
)0
995
(10
02)
362
4(4
126
)minus1
518
(minus2
263)
086
2(0
717
)18
Mou
thminus
572
minus54
43
AN
EE
L23
3989
734
6812
2468
8961
054
0(0
483
)0
211
(10
00)
673
2(7
289
)minus7
068
(minus8
460)
077
6(0
659
)19
Ped
rado
Ominus
457
minus54
05
AN
EE
L19
7125
5710
241
2744
4015
755
077
3(0
700
)0
988
(10
02)
319
3(3
690
)minus0
590
(minus1
123)
078
7(0
669
)20
Alta
mira
minus3
2minus
522
2A
NE
EL
2780
886
0932
298
9114
232
5187
70
798
(07
19)
098
1(0
998
)30
75
(35
75)minus0
578
(minus1
132)
086
1(0
714
)21
Sao
Fel
ipe
057
minus67
32
AN
EE
L19
1220
7406
1700
074
965
6018
057
087
7(0
814
)0
979
(09
72)
150
6(1
910
)0
572
(03
12)
079
9(0
684
)22
Uar
acu
055
minus69
17
AN
EE
L20
159
2459
5835
156
2675
6955
087
5(0
834
)0
991
(03
85)
166
4(1
957
)0
497
(03
04)
078
3(0
717
)23
Moc
idad
e3
45minus
610
5A
NE
EL
1316
213
0446
522
1291
7795
075
6(0
785
)0
494
(04
73)
255
2(2
346
)minus0
387
(minus0
172)
065
1(0
682
)24
Mal
oca
doC
onta
ominus
395
minus60
43
AN
EE
L23
3027
795
24
113
519
026
8(0
268
)0
997
(09
89)
325
2(3
252
)minus1
936
(minus1
936)
minus0
437
(minus0
437)
25M
ato
Gro
sso
minus15
02
minus59
97
AN
EE
L27
117
171
20
166
1029
073
5(0
724
)0
983
(10
02)
261
9(2
687
)minus0
152
(minus0
213)
056
0(0
544
)26
Pal
mei
ral
minus10
03
minus64
45
AN
EE
L12
121
486
10
200
767
083
1(0
831)
027
7(0
993
)18
73
(18
74)
039
7(0
397
)0
701
(07
01)
27A
rique
mes
minus10
03
minus62
97
AN
EE
L11
2832
211
350
123
474
061
0(0
610
)0
264
(02
63)
262
4(2
622
)minus0
201
(minus0
198)
062
2(0
623
)28
Sao
Car
los
minus9
7minus
631
3A
NE
EL
1244
341
1338
064
523
640
596
(05
92)
026
1(0
986
)46
42
(46
77)minus
326
0(minus
332
5)0
599
(05
90)
29C
acho
eira
doS
amue
lminus
905
minus63
47
AN
EE
L4
8626
011
332
636
2247
043
1(0
409
)0
581
(09
98)
616
2(6
384
)minus8
788
(minus9
506)
057
5(0
544
)30
San
taIs
abel
minus9
1minus
637
2A
NE
EL
1745
206
624
035
113
810
684
(06
76)
024
7(0
988
)48
26
(48
93)minus
298
1(minus
309
3)0
835
(08
23)
31C
acho
eira
Prim
aver
aminus
119
minus61
23
AN
EE
L19
9414
2942
801
508
2217
061
1(0
610
)0
967
(08
64)
320
2(3
209
)minus0
189
(minus0
193)
064
8(0
641
)32
Pim
enta
Bue
nominus
116
5minus
612
AN
EE
L24
2242
416
071
499
2217
078
6(0
784
)1
002
(09
91)
260
4(2
623
)minus0
028
(minus0
043)
065
4(0
649
)33
Boc
ado
Gua
riba
minus7
68minus
603
AN
EE
L29
4854
6531
070
618
6463
450
572
(05
60)
097
9(0
983
)17
78
(18
11)minus
013
5(minus
017
7)0
692
(06
17)
34S
anta
rem
Suc
undu
riminus
675
minus58
95
AN
EE
L22
013
183
96
980
3398
011
8(0
114
)0
992
(09
72)
151
23(1
520
7)minus
566
89(minus
573
31)
minus0
027
(minus0
041)
35E
stira
oda
Ang
elic
aminus
097
minus57
07
AN
EE
L22
1125
496
91
367
2211
049
8(0
498
)0
566
(09
97)
436
7(4
384
)minus2
819
(minus2
848)
034
0(0
342
)36
Boc
ado
Infe
rno
minus1
57minus
548
3A
NE
EL
1688
362
1257
361
330
110
385
(03
82)
046
6(0
464
)64
95
(64
61)minus
654
1(minus
646
4)0
306
(02
99)
37P
orto
Ron
cado
rminus
135
8minus
553
2A
NE
EL
2257
127
712
021
412
970
363
(03
63)
100
3(1
002
)40
69
(40
64)minus
860
1(minus
857
6)0
392
(03
93)
38Lu
cas
minus13
15
minus56
05
AN
EE
L26
111
560
50
181
1212
025
2(0
247
)0
971
(09
46)
455
2(4
581
)minus3
541
(minus3
598)
minus0
143
(minus0
155)
39B
arra
gem
Jusa
nte
minus12
78
minus54
27
AN
EE
L16
148
016
540
328
1921
022
4(0
219
)0
987
(09
91)
403
1(4
086
)minus1
711
(minus1
787)
minus0
342
(minus0
350)
40F
azen
daP
aqui
raminus
042
minus53
72
AN
EE
L23
2415
693
84
930
4435
007
9(0
079
)0
997
(10
01)
139
77(1
406
4)minus
924
42(minus
936
09)
004
2(0
042
)41
Por
toVe
lho
minus8
76minus
639
1R
ivD
IS11
3753
1753
938
975
327
1706
454
381
093
2(0
824
)0
094
(01
27)
184
4(2
896
)0
603
(00
20)
093
2(0
737
)42
Obi
dos
minus1
91minus
555
5N
A56
7151
715
603
624
600
030
567
148
176
294
334
091
1(0
626
)0
994
(09
95)
179
2(3
843
)0
527
(minus
117
7)0
880
(04
32)
43Lo
cota
lminus
170
4minus
660
2R
ivD
IS4
412
440
513
00
352
(03
52)
100
9(1
009
)53
35
(53
43)minus
499
4(minus
501
2)0
192
(01
92)
44A
ngos
tode
lBal
aminus
145
5minus
675
5R
ivD
IS4
404
2313
8614
1151
918
590
562
(05
62)
019
8(1
008
)28
74
(28
76)minus
041
3(minus
041
5)0
884
(08
84)
45V
illa
Bar
rient
osminus
163
2minus
672
5R
ivD
IS4
1578
252
047
227
085
4(0
854
)0
188
(01
87)
207
2(2
068
)0
506
(05
08)
083
7(0
838
)46
Alta
mira
minus3
2minus
522
1R
ivD
IS4
1007
8610
2698
414
614
394
4621
20
813
(07
26)
007
0(0
132
)35
52
(42
60)
minus0
538
(minus1
212)
090
8(0
748
)
1W
illm
ott(
1982
)ra
nge
1ndash0
perf
ectm
atch
(pm
)is
12
Jach
ner
etal
(20
07)
0ndashinfinp
mi
s0
3M
ayer
and
But
ler
(199
3)0
ndashinfinp
mi
s0
N-R
SM
E=10
0(R
SM
E(
obs m
ax-o
bsm
in)
4N
ash
and
Sut
cliff
e(1
970)
minusinfin
ndash1p
mi
s1
5se
ee
gJa
chne
ret
al(
2007
)minus
1ndash0ndash
1p
mi
s1
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2252 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
39
40
41
42
Figure 3 Observed and simulated discharge [m3 s
minus1] for all 44 sites Observed 826
discharge as solid grey line simulated discharge with routing velocity of 10 ms-1
as 827
dashed grey line and simulated discharge with slope depending routing velocity as 828
solid black line 829
830
Fig 3 Observed and simulated discharge [m3 sminus1] for all 44 sites Observed discharge as solid grey line simulated discharge with routingvelocity of 10 msminus1 as dashed grey line and simulated discharge with slope depending routing velocity as solid black line
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
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F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2248 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
characteristic and very diverse habitats for millions of plantand animal species which are intimately related to the recur-rent annual flooding These floodplains are alternately suit-able for aquatic and terrestrial organisms The distributionof these species is especially influenced by the duration ofthe aquatic and terrestrial phase (Junk and Piedade 1997)Floodplain forests cover approximately 97 000 km2 (Parolinet al 2004) and contain about 20 of the Amazonian treespecies (Naiman et al 2005) The vast floodplain areas thusrepresent one of the riches biota on earth providing severalecosystem services such as timber and fish production andcarbon storage (Keddy et al 2009)
Climate change is expected to alter temperature and pre-cipitation patterns which can potentially lead to changes inflood regime such as a reduction in discharge in the Ama-zon River (Arora and Boer 2001) The variability in precip-itation is expected to increase (Seneviratne et al 2012) andmay cause higher spatial and temporal variability in river dis-charge and flooded area (Coe et al 2002) The effect of cli-mate change on the El Nino Southern Oscillation (ENSO) re-mains unclear (Malhi and Wright 2004) but ENSO changesdischarge drastically (Foley et al 2002) Changes in timeduration and height of the flooding has the potential to shiftvegetation distribution which may in turn lead to feedbacksto the atmosphere (eg Cox et al 2004 Malhi et al 2008)
To assess the effects of potential changes in precipita-tion and temperature on discharge and freshwater ecosystemservices usually hydrological models are applied (Vigerstoland Aukema 2011) which are for example WaterGAP (Al-camo et al 2000 Doll and Zhang 2010 Doll et al 2003)WBM (Fekete et al 1999) and SWAT (Arnold and Fohrer2005) and VIC (Liang and Xie 2001 Liang et al 1994)A disadvantage of these models is that they do not incor-porate explicit simulation of vegetation dynamics which arean essential part of the water cycle We use the dynamicglobal vegetation and hydrology model LPJmL (Bondeau etal 2007 Gerten et al 2004 Rost et al 2008 Sitch et al2003) which has been improved for regional application tothe Amazon Basin and includes the dynamic and spatially ex-plicit reproduction of the specific hydrological patterns of themain river stem and its tributaries These patterns consist ofseasonal discharge time and duration of lowhigh water peri-ods and the changing extent of the flooded area during thoseperiods LPJmL combines dynamic terrestrial vegetation de-velopment with carbon and water cycles This enables us toestimate not only the direct effect of changing precipitationand temperature on discharge but also to include the indirecteffects of these changes on vegetation cover and type whichin turn alters runoff and discharge
The main goal of our study is thus to understand and quan-tify the magnitude of impacts of future climate change onthe Amazonian inundation patterns We provide estimates onclimate change induced shifts of inundation patterns whichcomprises of time and duration of lowhigh water periodsand the changing extent of the flooded area during those pe-
riods We describe here a method to calculate monthly in-undated area We evaluate our simulated results against ob-served data for discharge and potentially floodable area andestimate changes in inundation patterns in Amazonia Toquantify the amplitude of shifts in the flooding regime dueto climate change we use forcing data of the 24 General Cir-culation Models (GCMs) from the 4th Assessment Reportof the Intergovernmental Panel on Climate Change (IPCC2007 Randall et al 2007)
2 Methods
We apply the Dynamic Global Vegetation and HydrologyModel LPJmL (Sitch et al 2003 Gerten et al 2004 Bon-deau et al 2007 Rost et al 2008) to understand and to as-sess the effect of climate change on current Amazonian inun-dation patterns LPJmL computes establishment abundancevegetation dynamics growth and productivity of the worldrsquosmajor plant functional types as well as the associated carbonand water fluxes The model is typically applied on a gridof 05
times 05 longitudelatitude and at daily time steps Car-bon fluxes and vegetation dynamics are directly coupled towater fluxes Modelled soil moisture runoff and evapotran-spiration were found to reproduce observed patterns well andtheir quality is comparable to stand-alone global hydrologi-cal models (Wagner et al 2003 Gerten et al 2004 2008Gordon et al 2004 Biemans et al 2009)
The river routing module of LPJmL (described by Rost etal 2008) assumes a surface water storage pool for each gridcell representing the water storage and retention in reservoirsand lakes The change of water storage in the river over timeis represented as the runoff generated in the cell the input ofdischarge accumulated from upstream grid cells the outputto the downstream cell and the outflow of lakes in the respec-tive cell The output to the downstream cell is determinedas a linear transport of discharge depending on the routingvelocity (v) and the distance between the midpoints of theconnected cells Earlier versions of LPJmL used a globallyhomogeneous routing velocity of 1 msminus1 (Rost et al 2008)which had difficulties to reproduce the Amazonian hydro-graph with shifts within the hydrograph of several monthsIn a former study we already improved the reproduction ofthe hydrograph by applying a homogeneously reduced rout-ing velocity of 025 msminus1 to the Amazon Basin leading tosubstantial reductions of the shift for several observation sites(Langerwisch et al 2008) Our new approach is to use het-erogeneous routing velocities which take topographic differ-ences within the Amazon catchment into account for furtherimprovement of the hydrograph
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2249
Table 1Slope classes
Slope range Class
le 15 5gt 15ndashle 3 4gt 3ndashle 6 3gt 6ndashle 10 2gt 10ndashle 35 1gt 35 0
Table 2Relative slope position classes
Distance range Class
0ndash10 cells 2211ndash20 cells 1921ndash40 cells 1341ndash60 cells 1261ndash80 cells 11gt 81 cells 10
21 Calculation of routing velocity and potentialfloodable area
We extend on earlier work (Langerwisch et al 2008) andtake topography into account by calculating cell specificrouting velocities which are comparable to river flow veloc-ities In the model the routing velocity is used to calculatethe distance that runoff water can move within a time step(see also Rost et al 2008) We also estimate the extent ofpotential floodable area and monthly flooded area
We use a digital elevation model (DEM) provided by theWWF database HydroSHEDS (WWF HydroSHEDS 2007)at a resolution of 15 arc seconds longitudelatitude corre-sponding to approximately 460 m edge length in the study re-gion to calculate the routing velocity and the floodable areaWe apply grid-based elevation data (instead of elevation dataof the actual gauging stations) to obtain a continuous spa-tially consistent basis for our calculations The DEM eleva-tion represents the top of the canopy which issim 30 m lowerthan the actual ground elevation (Anderson et al 2009) Forthe Amazon Basin we assume this to be a systematic er-ror in the DEM elevation and use it directly for calculatingthe routing velocity The calculations of the routing veloc-ity were conducted applying well-established techniques (fordetails see Supplement S1 and S2) The data were processedat the original resolution of HydroSHEDS Final results arere-sampled at 05 times 05 (longitudelatitude) resolution
211 Routing velocity
Based on the DEM we calculate the cellrsquos slope and the cor-responding routing velocity (details see Supplement S1 andS2) The calculation of the high resolution slopeS [degree] is
Table 3Landform types with corresponding slope and mTRMI
Landform type Slope range mTRMI
valley flats lt 3 gt 22nearly level terraces lt 3
le 22gently sloping toe slopes and bottoms ge 3ndashlt 10 gt 18gently sloping ridges ge 3ndashlt 10
le 18very moist steep slopes ge 10ndashle 35
ge 18moderately moist steep slopes ge 10ndashle 35 11ndash17dry steep slopes ge 10ndashle 35 lt 10
based on the work of Burrough (1986) We apply the medianof all subcell values to aggregate the high resolution slope toa 05times 05 cell slope Subsequently we calculate slope de-pendent routing velocityv [msminus1] (Eq 1 Fig S1) based onthe ManningndashStrickler formulation
v =
(tan
(S times
π
180
)) 12times k times R
23 (1)
wherek is the ManningndashStrickler coefficient [m13 sminus1] de-scribing the roughness of the area For natural rivers thisvalue ranges between 28 and 40 m13 sminus1 (Patt 2001) Dueto the lack of detailed cell specific information we setk =
35 m13 sminus1 R is the hydraulic radius [m] It describes theratio between the cross-sectional area [m2] and the wettedperimeter [m] of the channel In wide and shallow watersit corresponds to the depth of the water It is higher in nar-row and deep river sections and lower in wide shallow riversections but cell specific information forR are not avail-able therefore we neglect the influence of this factor and setR = 10 m The median of the calculated routing velocity is025 msminus1 We included an analysis to estimate the sensitiv-ity of the calculated routing velocity tok andR We variedk between 28 and 40 m13 sminus1 (with a constantR = 10 m)which lead to median routing velocities between 020 msminus1
(minus200 ) and 029 msminus1 (+16 ) We variedR between 02and 12 m (with a constantk = 35 m13 sminus1) which lead tomedian routing velocities between 009 msminus1 (minus64 ) and029 msminus1 (+169 ) Additionally we tested all possiblekandR combinations in the range given above (see Fig S2)
212 Floodable area
As a basis for the calculation of inundation we first estimatethe potentially floodable area by applying the same DEMused for the routing velocity calculation (see Sect 211)We determine a modified Topographic Relative Moisture In-dex (mTRMI) based on the work of Parker (1982) on thenative resolution of the DEM (15 arc seconds) This indexis applied to classify structural landscape conditions whichcan be arranged in 7 different landform types such asvalleyflatsanddry steep slopes(also see Tables 1ndash3) It uses sev-eral weighted geomorphologic characteristics such as slopeslope steepness slope configuration relative slope position
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2250 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Table 4 List of the 24 IPCC coupled general circulation models(GCMs) used in this study Details for the climate models see IPCC2007 AR4 chapter 8 (Randall et al 2007)
Model name
BCCR ndash BCM 20 INGV ndash SXGCCCMA ndash CGCM 31 (T47) INM ndash CM 30CCCMA ndash CGCM 31 (T63) IPSL ndash CM 4CNRM ndash CM 3 MIROC 32 (hires)CSIRO ndash Mk 30 MIROC 32 (medres)CSIRO ndash Mk 35 MIUB ndash ECHO-GGFDL ndash CM 20 MPI ndash ECHAM 5GFDL ndash CM 21 MRI ndash CGCM 232aGISS ndash AOM NCAR ndash CCSM 3GISS ndash EH NCAR ndash PCM 1GISS ndash ER UKMO ndash HadCM 3FGOALS ndash g 10 UKMO ndash HadGEM 1
Fig 1 Simulated mean discharge [log m3 sminus1] during June aver-aged over the reference period 1961ndash1990 The white crosses indi-cate the exaple sites Cruzeiro do Sul (CdS ID 3) Porto Velho (PVID 41) andObidos (Obi ID 10 and 42)
and aspect which can be calculated from the DEM We usethe resulting landform type valley flats as potentially flood-able area
In our study mTRMI is the sum of classified slope classi-fied slope configuration and classified relative slope position(Eq 2 see below for definitions)
mTRMI = Sclass+ Sconfigclass+ Sposclass
(2)
We neglect aspect because differences between north andsouth facing slopes are insignificant in the tropics (compareto Donnegan et al 2007) A detailed description of the calcu-lation of mTRMI summands can be found in the Supplement
The first summand is classified slope (Eq 2Sclass) Weuse the previously calculated slope values and slice them insix slope classes (Table 1)
38
823
Figure 2 The 44 sites used for comparison of observed and simulated discharge 824
825
Fig 2The 44 sites used for comparison of observed and simulateddischarge
The second summand is classified slope configuration(Eq 2Sconfclass) Slope configuration describes the convex-ity or concavity of the land surrounding any grid cell basedon the change in elevationZ [m] from cellij to all cells lo-cated at the edge of the 5times 5 cell window We slice the fullrange of resulting values equally into 10 parts and assignthese parts into 3 slope configuration classes slices 0ndash4 toclassminus1 (convex topography) slice 5 to class 0 (flat topog-raphy) slices 6ndash10 to class 1 (concave topography)
The third summand is relative slope position (Eq 2Sposclass
) describing the distance of the cellij to the closestridges and streams We assign the distance [cells] to 6 relativeslope position classes (Table 2)
From the slope classes (Eqs S1ndashS3) the slope configu-ration classes (Eqs S5ndashS9) and the relative slope positionclasses (Eqs S10ndashS11) we calculate mTRMI (Eq 2) Wesum up classified slope (0 to 5) classified slope configura-tion (minus1 to 1) and classified relative slope position (10 to22) The mTRMI ranges from dry to wet (9 to 28) describingsite conditions
We generate a map (15 arc seconds resolution) of landformtypes by combining slopeS and mTRMI For this purpose wegroup sites with defined mTRMI and slope to certain land-form types (details in Table 3) Finally we use the landformtype valley flat which is potentially floodable area to cal-culate the fraction [] of floodable area for each 05times 05
grid cellWe then calculate the fraction of continuously flooded area
from the potentially floodable area (per 05times 05 cell) fromthe work of Richey et al (2002) They estimated that duringlow water stage about 4 and during high water stage about16 of a 177 million km2 quadrant of the central Ama-zon Basin is covered with water This means that 25 of
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2251
Tabl
e5
Com
paris
onof
obse
rved
and
sim
ulat
eddi
scha
rge
for
the
obse
rvat
ion
perio
d(s
eeal
soF
igs
3an
d4)
Ind
ices
are
give
nfo
rth
est
anda
rdsi
mul
atio
n(s
td)
with
slop
ede
pend
ent
rout
ing
velo
city
and
orig
inal
setti
ng(1
0m
sminus
1)
with
hom
ogen
eous
rout
ing
velo
city
of1
0m
sminus
1in
brac
kets
IDS
tatio
nLa
titud
eLo
ngitu
deD
atab
ase
Num
ber
ofob
sye
ars
Obs
erve
dm
inan
nual
disc
harg
e[m
3sminus
1]
Obs
erve
dm
ean
annu
aldi
scha
rge
[m3
sminus1]
Obs
erve
dm
axan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
inan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
ean
annu
aldi
scha
rge
[m3
sminus1]
Sim
ulat
edm
axan
nual
disc
harg
e[m
3sminus
1]
Will
mot
trsquosin
dex
ofag
reem
ent1st
d(1
0m
sminus1)
Err
orof
Qua
lV2
std
(10
msminus
1)
N-R
MS
E3[
]st
d(1
0m
sminus1)
Nas
hndashS
utcl
iffe4
std
(10
msminus
1)
Pea
rson
corr
elat
ion
coef
ficie
nt5st
d(1
0m
sminus1)
1E
stira
odo
Rep
ouso
minus4
37minus
709
3A
NE
EL
1619
325
1847
4915
525
9272
700
870
(07
93)
100
3(0
367
)21
27
(27
75)
037
0(
minus0
073)
079
1(0
678
)2
Sao
Pau
lode
Oliv
enca
minus3
47minus
687
5A
NE
EL
2315
272
4644
278
410
4013
2627
055
717
060
3(0
590
)0
322
(09
56)
347
0(3
596
)minus
136
0(minus
153
5)0
801
(06
94)
3C
ruze
irodo
Sul
minus7
62minus
726
7A
NE
EL
2975
907
2992
2411
0644
890
880
(08
48)
026
3(0
998
)19
68
(22
75)
036
6(0
153
)0
839
(07
96)
4G
avia
ominus
483
minus66
75
AN
EE
L23
603
4732
9932
151
5683
1786
80
855
(07
54)
096
4(0
993
)29
05
(36
94)
013
1(
minus0
405)
082
6(0
652
)5
Aca
naui
minus1
8minus
665
5A
NE
EL
2329
0013
778
2553
329
5511
611
2588
20
693
(06
12)
099
1(0
953
)22
26
(25
51)
minus0
120
(minus0
471)
051
4(0
358
)6
Flo
riano
Pei
xoto
minus9
05minus
673
8A
NE
EL
3027
583
2062
881
335
790
835
(07
93)
024
5(0
974
)26
45
(30
32)
000
7(
minus0
305)
081
0(0
751
)7
Labr
eaminus
725
minus64
8A
NE
EL
3072
354
4411
739
101
6241
2279
90
867
(07
71)
099
3(0
991
)30
60
(40
14)
023
2(
minus0
321)
082
5(0
666
)8
Ser
rinha
minus0
45minus
648
3A
NE
EL
2035
9915
980
3043
434
8615
975
3567
60
910
(08
12)
029
1(1
002
)13
71
(20
37)
064
9(0
225
)0
832
(06
68)
9C
arac
arai
18
minus61
13
AN
EE
L30
244
2898
1117
816
3681
1739
60
868
(08
13)
100
1(0
995
)21
22
(25
95)
015
0(
minus0
271)
086
7(0
790
)10
Obi
dos
minus1
9minus
555
05A
NE
EL
2875
602
172
696
306
318
4275
814
783
429
433
40
873
(06
13)
099
6(0
995
)17
08
(30
76)
035
6(
minus1
090)
086
8(0
426
)11
Por
todo
sG
auch
osminus
116
5minus
572
3A
NE
EL
2233
376
217
021
1077
4248
054
7(0
501
)0
986
(09
45)
714
9(7
786
)minus8
188
(minus9
899)
073
8(0
663
)12
Cac
hoei
rao
minus11
75
minus55
77
AN
EE
L20
224
815
2287
214
4364
340
541
(05
00)
024
6(0
962
)68
39
(73
59)minus
894
9(minus
105
22)
078
3(0
716
)13
Inde
cominus
101
3minus
554
2A
NE
EL
2037
011
4834
650
685
3899
074
2(0
735
)0
304
(10
02)
240
5(2
450
)minus0
200
(minus0
245)
067
4(0
659
)14
Tre
sM
aria
sminus
763
minus57
88
AN
EE
L15
429
3759
1036
59
5801
2244
40
715
(06
60)
098
4(0
966
)44
81
(49
23)minus
202
1(minus
264
7)0
791
(06
93)
15Ja
toba
minus5
15minus
568
3A
NE
EL
2236
4910
790
2633
430
1448
948
219
077
6(0
729
)0
996
(09
89)
414
8(4
512
)minus
125
5(minus
166
9)0
872
(07
75)
16S
aoF
elix
doX
ingu
minus6
58minus
520
5A
NE
EL
2369
750
8821
660
979
6331
724
072
4(0
646
)0
324
(09
50)
295
7(3
340
)minus1
331
(minus1
974)
075
5(0
618
)17
Bel
oH
oriz
onte
minus5
38minus
528
8A
NE
EL
2275
952
3218
818
2085
4234
269
075
1(0
673
)0
995
(10
02)
362
4(4
126
)minus1
518
(minus2
263)
086
2(0
717
)18
Mou
thminus
572
minus54
43
AN
EE
L23
3989
734
6812
2468
8961
054
0(0
483
)0
211
(10
00)
673
2(7
289
)minus7
068
(minus8
460)
077
6(0
659
)19
Ped
rado
Ominus
457
minus54
05
AN
EE
L19
7125
5710
241
2744
4015
755
077
3(0
700
)0
988
(10
02)
319
3(3
690
)minus0
590
(minus1
123)
078
7(0
669
)20
Alta
mira
minus3
2minus
522
2A
NE
EL
2780
886
0932
298
9114
232
5187
70
798
(07
19)
098
1(0
998
)30
75
(35
75)minus0
578
(minus1
132)
086
1(0
714
)21
Sao
Fel
ipe
057
minus67
32
AN
EE
L19
1220
7406
1700
074
965
6018
057
087
7(0
814
)0
979
(09
72)
150
6(1
910
)0
572
(03
12)
079
9(0
684
)22
Uar
acu
055
minus69
17
AN
EE
L20
159
2459
5835
156
2675
6955
087
5(0
834
)0
991
(03
85)
166
4(1
957
)0
497
(03
04)
078
3(0
717
)23
Moc
idad
e3
45minus
610
5A
NE
EL
1316
213
0446
522
1291
7795
075
6(0
785
)0
494
(04
73)
255
2(2
346
)minus0
387
(minus0
172)
065
1(0
682
)24
Mal
oca
doC
onta
ominus
395
minus60
43
AN
EE
L23
3027
795
24
113
519
026
8(0
268
)0
997
(09
89)
325
2(3
252
)minus1
936
(minus1
936)
minus0
437
(minus0
437)
25M
ato
Gro
sso
minus15
02
minus59
97
AN
EE
L27
117
171
20
166
1029
073
5(0
724
)0
983
(10
02)
261
9(2
687
)minus0
152
(minus0
213)
056
0(0
544
)26
Pal
mei
ral
minus10
03
minus64
45
AN
EE
L12
121
486
10
200
767
083
1(0
831)
027
7(0
993
)18
73
(18
74)
039
7(0
397
)0
701
(07
01)
27A
rique
mes
minus10
03
minus62
97
AN
EE
L11
2832
211
350
123
474
061
0(0
610
)0
264
(02
63)
262
4(2
622
)minus0
201
(minus0
198)
062
2(0
623
)28
Sao
Car
los
minus9
7minus
631
3A
NE
EL
1244
341
1338
064
523
640
596
(05
92)
026
1(0
986
)46
42
(46
77)minus
326
0(minus
332
5)0
599
(05
90)
29C
acho
eira
doS
amue
lminus
905
minus63
47
AN
EE
L4
8626
011
332
636
2247
043
1(0
409
)0
581
(09
98)
616
2(6
384
)minus8
788
(minus9
506)
057
5(0
544
)30
San
taIs
abel
minus9
1minus
637
2A
NE
EL
1745
206
624
035
113
810
684
(06
76)
024
7(0
988
)48
26
(48
93)minus
298
1(minus
309
3)0
835
(08
23)
31C
acho
eira
Prim
aver
aminus
119
minus61
23
AN
EE
L19
9414
2942
801
508
2217
061
1(0
610
)0
967
(08
64)
320
2(3
209
)minus0
189
(minus0
193)
064
8(0
641
)32
Pim
enta
Bue
nominus
116
5minus
612
AN
EE
L24
2242
416
071
499
2217
078
6(0
784
)1
002
(09
91)
260
4(2
623
)minus0
028
(minus0
043)
065
4(0
649
)33
Boc
ado
Gua
riba
minus7
68minus
603
AN
EE
L29
4854
6531
070
618
6463
450
572
(05
60)
097
9(0
983
)17
78
(18
11)minus
013
5(minus
017
7)0
692
(06
17)
34S
anta
rem
Suc
undu
riminus
675
minus58
95
AN
EE
L22
013
183
96
980
3398
011
8(0
114
)0
992
(09
72)
151
23(1
520
7)minus
566
89(minus
573
31)
minus0
027
(minus0
041)
35E
stira
oda
Ang
elic
aminus
097
minus57
07
AN
EE
L22
1125
496
91
367
2211
049
8(0
498
)0
566
(09
97)
436
7(4
384
)minus2
819
(minus2
848)
034
0(0
342
)36
Boc
ado
Infe
rno
minus1
57minus
548
3A
NE
EL
1688
362
1257
361
330
110
385
(03
82)
046
6(0
464
)64
95
(64
61)minus
654
1(minus
646
4)0
306
(02
99)
37P
orto
Ron
cado
rminus
135
8minus
553
2A
NE
EL
2257
127
712
021
412
970
363
(03
63)
100
3(1
002
)40
69
(40
64)minus
860
1(minus
857
6)0
392
(03
93)
38Lu
cas
minus13
15
minus56
05
AN
EE
L26
111
560
50
181
1212
025
2(0
247
)0
971
(09
46)
455
2(4
581
)minus3
541
(minus3
598)
minus0
143
(minus0
155)
39B
arra
gem
Jusa
nte
minus12
78
minus54
27
AN
EE
L16
148
016
540
328
1921
022
4(0
219
)0
987
(09
91)
403
1(4
086
)minus1
711
(minus1
787)
minus0
342
(minus0
350)
40F
azen
daP
aqui
raminus
042
minus53
72
AN
EE
L23
2415
693
84
930
4435
007
9(0
079
)0
997
(10
01)
139
77(1
406
4)minus
924
42(minus
936
09)
004
2(0
042
)41
Por
toVe
lho
minus8
76minus
639
1R
ivD
IS11
3753
1753
938
975
327
1706
454
381
093
2(0
824
)0
094
(01
27)
184
4(2
896
)0
603
(00
20)
093
2(0
737
)42
Obi
dos
minus1
91minus
555
5N
A56
7151
715
603
624
600
030
567
148
176
294
334
091
1(0
626
)0
994
(09
95)
179
2(3
843
)0
527
(minus
117
7)0
880
(04
32)
43Lo
cota
lminus
170
4minus
660
2R
ivD
IS4
412
440
513
00
352
(03
52)
100
9(1
009
)53
35
(53
43)minus
499
4(minus
501
2)0
192
(01
92)
44A
ngos
tode
lBal
aminus
145
5minus
675
5R
ivD
IS4
404
2313
8614
1151
918
590
562
(05
62)
019
8(1
008
)28
74
(28
76)minus
041
3(minus
041
5)0
884
(08
84)
45V
illa
Bar
rient
osminus
163
2minus
672
5R
ivD
IS4
1578
252
047
227
085
4(0
854
)0
188
(01
87)
207
2(2
068
)0
506
(05
08)
083
7(0
838
)46
Alta
mira
minus3
2minus
522
1R
ivD
IS4
1007
8610
2698
414
614
394
4621
20
813
(07
26)
007
0(0
132
)35
52
(42
60)
minus0
538
(minus1
212)
090
8(0
748
)
1W
illm
ott(
1982
)ra
nge
1ndash0
perf
ectm
atch
(pm
)is
12
Jach
ner
etal
(20
07)
0ndashinfinp
mi
s0
3M
ayer
and
But
ler
(199
3)0
ndashinfinp
mi
s0
N-R
SM
E=10
0(R
SM
E(
obs m
ax-o
bsm
in)
4N
ash
and
Sut
cliff
e(1
970)
minusinfin
ndash1p
mi
s1
5se
ee
gJa
chne
ret
al(
2007
)minus
1ndash0ndash
1p
mi
s1
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2252 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
39
40
41
42
Figure 3 Observed and simulated discharge [m3 s
minus1] for all 44 sites Observed 826
discharge as solid grey line simulated discharge with routing velocity of 10 ms-1
as 827
dashed grey line and simulated discharge with slope depending routing velocity as 828
solid black line 829
830
Fig 3 Observed and simulated discharge [m3 sminus1] for all 44 sites Observed discharge as solid grey line simulated discharge with routingvelocity of 10 msminus1 as dashed grey line and simulated discharge with slope depending routing velocity as solid black line
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2249
Table 1Slope classes
Slope range Class
le 15 5gt 15ndashle 3 4gt 3ndashle 6 3gt 6ndashle 10 2gt 10ndashle 35 1gt 35 0
Table 2Relative slope position classes
Distance range Class
0ndash10 cells 2211ndash20 cells 1921ndash40 cells 1341ndash60 cells 1261ndash80 cells 11gt 81 cells 10
21 Calculation of routing velocity and potentialfloodable area
We extend on earlier work (Langerwisch et al 2008) andtake topography into account by calculating cell specificrouting velocities which are comparable to river flow veloc-ities In the model the routing velocity is used to calculatethe distance that runoff water can move within a time step(see also Rost et al 2008) We also estimate the extent ofpotential floodable area and monthly flooded area
We use a digital elevation model (DEM) provided by theWWF database HydroSHEDS (WWF HydroSHEDS 2007)at a resolution of 15 arc seconds longitudelatitude corre-sponding to approximately 460 m edge length in the study re-gion to calculate the routing velocity and the floodable areaWe apply grid-based elevation data (instead of elevation dataof the actual gauging stations) to obtain a continuous spa-tially consistent basis for our calculations The DEM eleva-tion represents the top of the canopy which issim 30 m lowerthan the actual ground elevation (Anderson et al 2009) Forthe Amazon Basin we assume this to be a systematic er-ror in the DEM elevation and use it directly for calculatingthe routing velocity The calculations of the routing veloc-ity were conducted applying well-established techniques (fordetails see Supplement S1 and S2) The data were processedat the original resolution of HydroSHEDS Final results arere-sampled at 05 times 05 (longitudelatitude) resolution
211 Routing velocity
Based on the DEM we calculate the cellrsquos slope and the cor-responding routing velocity (details see Supplement S1 andS2) The calculation of the high resolution slopeS [degree] is
Table 3Landform types with corresponding slope and mTRMI
Landform type Slope range mTRMI
valley flats lt 3 gt 22nearly level terraces lt 3
le 22gently sloping toe slopes and bottoms ge 3ndashlt 10 gt 18gently sloping ridges ge 3ndashlt 10
le 18very moist steep slopes ge 10ndashle 35
ge 18moderately moist steep slopes ge 10ndashle 35 11ndash17dry steep slopes ge 10ndashle 35 lt 10
based on the work of Burrough (1986) We apply the medianof all subcell values to aggregate the high resolution slope toa 05times 05 cell slope Subsequently we calculate slope de-pendent routing velocityv [msminus1] (Eq 1 Fig S1) based onthe ManningndashStrickler formulation
v =
(tan
(S times
π
180
)) 12times k times R
23 (1)
wherek is the ManningndashStrickler coefficient [m13 sminus1] de-scribing the roughness of the area For natural rivers thisvalue ranges between 28 and 40 m13 sminus1 (Patt 2001) Dueto the lack of detailed cell specific information we setk =
35 m13 sminus1 R is the hydraulic radius [m] It describes theratio between the cross-sectional area [m2] and the wettedperimeter [m] of the channel In wide and shallow watersit corresponds to the depth of the water It is higher in nar-row and deep river sections and lower in wide shallow riversections but cell specific information forR are not avail-able therefore we neglect the influence of this factor and setR = 10 m The median of the calculated routing velocity is025 msminus1 We included an analysis to estimate the sensitiv-ity of the calculated routing velocity tok andR We variedk between 28 and 40 m13 sminus1 (with a constantR = 10 m)which lead to median routing velocities between 020 msminus1
(minus200 ) and 029 msminus1 (+16 ) We variedR between 02and 12 m (with a constantk = 35 m13 sminus1) which lead tomedian routing velocities between 009 msminus1 (minus64 ) and029 msminus1 (+169 ) Additionally we tested all possiblekandR combinations in the range given above (see Fig S2)
212 Floodable area
As a basis for the calculation of inundation we first estimatethe potentially floodable area by applying the same DEMused for the routing velocity calculation (see Sect 211)We determine a modified Topographic Relative Moisture In-dex (mTRMI) based on the work of Parker (1982) on thenative resolution of the DEM (15 arc seconds) This indexis applied to classify structural landscape conditions whichcan be arranged in 7 different landform types such asvalleyflatsanddry steep slopes(also see Tables 1ndash3) It uses sev-eral weighted geomorphologic characteristics such as slopeslope steepness slope configuration relative slope position
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2250 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Table 4 List of the 24 IPCC coupled general circulation models(GCMs) used in this study Details for the climate models see IPCC2007 AR4 chapter 8 (Randall et al 2007)
Model name
BCCR ndash BCM 20 INGV ndash SXGCCCMA ndash CGCM 31 (T47) INM ndash CM 30CCCMA ndash CGCM 31 (T63) IPSL ndash CM 4CNRM ndash CM 3 MIROC 32 (hires)CSIRO ndash Mk 30 MIROC 32 (medres)CSIRO ndash Mk 35 MIUB ndash ECHO-GGFDL ndash CM 20 MPI ndash ECHAM 5GFDL ndash CM 21 MRI ndash CGCM 232aGISS ndash AOM NCAR ndash CCSM 3GISS ndash EH NCAR ndash PCM 1GISS ndash ER UKMO ndash HadCM 3FGOALS ndash g 10 UKMO ndash HadGEM 1
Fig 1 Simulated mean discharge [log m3 sminus1] during June aver-aged over the reference period 1961ndash1990 The white crosses indi-cate the exaple sites Cruzeiro do Sul (CdS ID 3) Porto Velho (PVID 41) andObidos (Obi ID 10 and 42)
and aspect which can be calculated from the DEM We usethe resulting landform type valley flats as potentially flood-able area
In our study mTRMI is the sum of classified slope classi-fied slope configuration and classified relative slope position(Eq 2 see below for definitions)
mTRMI = Sclass+ Sconfigclass+ Sposclass
(2)
We neglect aspect because differences between north andsouth facing slopes are insignificant in the tropics (compareto Donnegan et al 2007) A detailed description of the calcu-lation of mTRMI summands can be found in the Supplement
The first summand is classified slope (Eq 2Sclass) Weuse the previously calculated slope values and slice them insix slope classes (Table 1)
38
823
Figure 2 The 44 sites used for comparison of observed and simulated discharge 824
825
Fig 2The 44 sites used for comparison of observed and simulateddischarge
The second summand is classified slope configuration(Eq 2Sconfclass) Slope configuration describes the convex-ity or concavity of the land surrounding any grid cell basedon the change in elevationZ [m] from cellij to all cells lo-cated at the edge of the 5times 5 cell window We slice the fullrange of resulting values equally into 10 parts and assignthese parts into 3 slope configuration classes slices 0ndash4 toclassminus1 (convex topography) slice 5 to class 0 (flat topog-raphy) slices 6ndash10 to class 1 (concave topography)
The third summand is relative slope position (Eq 2Sposclass
) describing the distance of the cellij to the closestridges and streams We assign the distance [cells] to 6 relativeslope position classes (Table 2)
From the slope classes (Eqs S1ndashS3) the slope configu-ration classes (Eqs S5ndashS9) and the relative slope positionclasses (Eqs S10ndashS11) we calculate mTRMI (Eq 2) Wesum up classified slope (0 to 5) classified slope configura-tion (minus1 to 1) and classified relative slope position (10 to22) The mTRMI ranges from dry to wet (9 to 28) describingsite conditions
We generate a map (15 arc seconds resolution) of landformtypes by combining slopeS and mTRMI For this purpose wegroup sites with defined mTRMI and slope to certain land-form types (details in Table 3) Finally we use the landformtype valley flat which is potentially floodable area to cal-culate the fraction [] of floodable area for each 05times 05
grid cellWe then calculate the fraction of continuously flooded area
from the potentially floodable area (per 05times 05 cell) fromthe work of Richey et al (2002) They estimated that duringlow water stage about 4 and during high water stage about16 of a 177 million km2 quadrant of the central Ama-zon Basin is covered with water This means that 25 of
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2251
Tabl
e5
Com
paris
onof
obse
rved
and
sim
ulat
eddi
scha
rge
for
the
obse
rvat
ion
perio
d(s
eeal
soF
igs
3an
d4)
Ind
ices
are
give
nfo
rth
est
anda
rdsi
mul
atio
n(s
td)
with
slop
ede
pend
ent
rout
ing
velo
city
and
orig
inal
setti
ng(1
0m
sminus
1)
with
hom
ogen
eous
rout
ing
velo
city
of1
0m
sminus
1in
brac
kets
IDS
tatio
nLa
titud
eLo
ngitu
deD
atab
ase
Num
ber
ofob
sye
ars
Obs
erve
dm
inan
nual
disc
harg
e[m
3sminus
1]
Obs
erve
dm
ean
annu
aldi
scha
rge
[m3
sminus1]
Obs
erve
dm
axan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
inan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
ean
annu
aldi
scha
rge
[m3
sminus1]
Sim
ulat
edm
axan
nual
disc
harg
e[m
3sminus
1]
Will
mot
trsquosin
dex
ofag
reem
ent1st
d(1
0m
sminus1)
Err
orof
Qua
lV2
std
(10
msminus
1)
N-R
MS
E3[
]st
d(1
0m
sminus1)
Nas
hndashS
utcl
iffe4
std
(10
msminus
1)
Pea
rson
corr
elat
ion
coef
ficie
nt5st
d(1
0m
sminus1)
1E
stira
odo
Rep
ouso
minus4
37minus
709
3A
NE
EL
1619
325
1847
4915
525
9272
700
870
(07
93)
100
3(0
367
)21
27
(27
75)
037
0(
minus0
073)
079
1(0
678
)2
Sao
Pau
lode
Oliv
enca
minus3
47minus
687
5A
NE
EL
2315
272
4644
278
410
4013
2627
055
717
060
3(0
590
)0
322
(09
56)
347
0(3
596
)minus
136
0(minus
153
5)0
801
(06
94)
3C
ruze
irodo
Sul
minus7
62minus
726
7A
NE
EL
2975
907
2992
2411
0644
890
880
(08
48)
026
3(0
998
)19
68
(22
75)
036
6(0
153
)0
839
(07
96)
4G
avia
ominus
483
minus66
75
AN
EE
L23
603
4732
9932
151
5683
1786
80
855
(07
54)
096
4(0
993
)29
05
(36
94)
013
1(
minus0
405)
082
6(0
652
)5
Aca
naui
minus1
8minus
665
5A
NE
EL
2329
0013
778
2553
329
5511
611
2588
20
693
(06
12)
099
1(0
953
)22
26
(25
51)
minus0
120
(minus0
471)
051
4(0
358
)6
Flo
riano
Pei
xoto
minus9
05minus
673
8A
NE
EL
3027
583
2062
881
335
790
835
(07
93)
024
5(0
974
)26
45
(30
32)
000
7(
minus0
305)
081
0(0
751
)7
Labr
eaminus
725
minus64
8A
NE
EL
3072
354
4411
739
101
6241
2279
90
867
(07
71)
099
3(0
991
)30
60
(40
14)
023
2(
minus0
321)
082
5(0
666
)8
Ser
rinha
minus0
45minus
648
3A
NE
EL
2035
9915
980
3043
434
8615
975
3567
60
910
(08
12)
029
1(1
002
)13
71
(20
37)
064
9(0
225
)0
832
(06
68)
9C
arac
arai
18
minus61
13
AN
EE
L30
244
2898
1117
816
3681
1739
60
868
(08
13)
100
1(0
995
)21
22
(25
95)
015
0(
minus0
271)
086
7(0
790
)10
Obi
dos
minus1
9minus
555
05A
NE
EL
2875
602
172
696
306
318
4275
814
783
429
433
40
873
(06
13)
099
6(0
995
)17
08
(30
76)
035
6(
minus1
090)
086
8(0
426
)11
Por
todo
sG
auch
osminus
116
5minus
572
3A
NE
EL
2233
376
217
021
1077
4248
054
7(0
501
)0
986
(09
45)
714
9(7
786
)minus8
188
(minus9
899)
073
8(0
663
)12
Cac
hoei
rao
minus11
75
minus55
77
AN
EE
L20
224
815
2287
214
4364
340
541
(05
00)
024
6(0
962
)68
39
(73
59)minus
894
9(minus
105
22)
078
3(0
716
)13
Inde
cominus
101
3minus
554
2A
NE
EL
2037
011
4834
650
685
3899
074
2(0
735
)0
304
(10
02)
240
5(2
450
)minus0
200
(minus0
245)
067
4(0
659
)14
Tre
sM
aria
sminus
763
minus57
88
AN
EE
L15
429
3759
1036
59
5801
2244
40
715
(06
60)
098
4(0
966
)44
81
(49
23)minus
202
1(minus
264
7)0
791
(06
93)
15Ja
toba
minus5
15minus
568
3A
NE
EL
2236
4910
790
2633
430
1448
948
219
077
6(0
729
)0
996
(09
89)
414
8(4
512
)minus
125
5(minus
166
9)0
872
(07
75)
16S
aoF
elix
doX
ingu
minus6
58minus
520
5A
NE
EL
2369
750
8821
660
979
6331
724
072
4(0
646
)0
324
(09
50)
295
7(3
340
)minus1
331
(minus1
974)
075
5(0
618
)17
Bel
oH
oriz
onte
minus5
38minus
528
8A
NE
EL
2275
952
3218
818
2085
4234
269
075
1(0
673
)0
995
(10
02)
362
4(4
126
)minus1
518
(minus2
263)
086
2(0
717
)18
Mou
thminus
572
minus54
43
AN
EE
L23
3989
734
6812
2468
8961
054
0(0
483
)0
211
(10
00)
673
2(7
289
)minus7
068
(minus8
460)
077
6(0
659
)19
Ped
rado
Ominus
457
minus54
05
AN
EE
L19
7125
5710
241
2744
4015
755
077
3(0
700
)0
988
(10
02)
319
3(3
690
)minus0
590
(minus1
123)
078
7(0
669
)20
Alta
mira
minus3
2minus
522
2A
NE
EL
2780
886
0932
298
9114
232
5187
70
798
(07
19)
098
1(0
998
)30
75
(35
75)minus0
578
(minus1
132)
086
1(0
714
)21
Sao
Fel
ipe
057
minus67
32
AN
EE
L19
1220
7406
1700
074
965
6018
057
087
7(0
814
)0
979
(09
72)
150
6(1
910
)0
572
(03
12)
079
9(0
684
)22
Uar
acu
055
minus69
17
AN
EE
L20
159
2459
5835
156
2675
6955
087
5(0
834
)0
991
(03
85)
166
4(1
957
)0
497
(03
04)
078
3(0
717
)23
Moc
idad
e3
45minus
610
5A
NE
EL
1316
213
0446
522
1291
7795
075
6(0
785
)0
494
(04
73)
255
2(2
346
)minus0
387
(minus0
172)
065
1(0
682
)24
Mal
oca
doC
onta
ominus
395
minus60
43
AN
EE
L23
3027
795
24
113
519
026
8(0
268
)0
997
(09
89)
325
2(3
252
)minus1
936
(minus1
936)
minus0
437
(minus0
437)
25M
ato
Gro
sso
minus15
02
minus59
97
AN
EE
L27
117
171
20
166
1029
073
5(0
724
)0
983
(10
02)
261
9(2
687
)minus0
152
(minus0
213)
056
0(0
544
)26
Pal
mei
ral
minus10
03
minus64
45
AN
EE
L12
121
486
10
200
767
083
1(0
831)
027
7(0
993
)18
73
(18
74)
039
7(0
397
)0
701
(07
01)
27A
rique
mes
minus10
03
minus62
97
AN
EE
L11
2832
211
350
123
474
061
0(0
610
)0
264
(02
63)
262
4(2
622
)minus0
201
(minus0
198)
062
2(0
623
)28
Sao
Car
los
minus9
7minus
631
3A
NE
EL
1244
341
1338
064
523
640
596
(05
92)
026
1(0
986
)46
42
(46
77)minus
326
0(minus
332
5)0
599
(05
90)
29C
acho
eira
doS
amue
lminus
905
minus63
47
AN
EE
L4
8626
011
332
636
2247
043
1(0
409
)0
581
(09
98)
616
2(6
384
)minus8
788
(minus9
506)
057
5(0
544
)30
San
taIs
abel
minus9
1minus
637
2A
NE
EL
1745
206
624
035
113
810
684
(06
76)
024
7(0
988
)48
26
(48
93)minus
298
1(minus
309
3)0
835
(08
23)
31C
acho
eira
Prim
aver
aminus
119
minus61
23
AN
EE
L19
9414
2942
801
508
2217
061
1(0
610
)0
967
(08
64)
320
2(3
209
)minus0
189
(minus0
193)
064
8(0
641
)32
Pim
enta
Bue
nominus
116
5minus
612
AN
EE
L24
2242
416
071
499
2217
078
6(0
784
)1
002
(09
91)
260
4(2
623
)minus0
028
(minus0
043)
065
4(0
649
)33
Boc
ado
Gua
riba
minus7
68minus
603
AN
EE
L29
4854
6531
070
618
6463
450
572
(05
60)
097
9(0
983
)17
78
(18
11)minus
013
5(minus
017
7)0
692
(06
17)
34S
anta
rem
Suc
undu
riminus
675
minus58
95
AN
EE
L22
013
183
96
980
3398
011
8(0
114
)0
992
(09
72)
151
23(1
520
7)minus
566
89(minus
573
31)
minus0
027
(minus0
041)
35E
stira
oda
Ang
elic
aminus
097
minus57
07
AN
EE
L22
1125
496
91
367
2211
049
8(0
498
)0
566
(09
97)
436
7(4
384
)minus2
819
(minus2
848)
034
0(0
342
)36
Boc
ado
Infe
rno
minus1
57minus
548
3A
NE
EL
1688
362
1257
361
330
110
385
(03
82)
046
6(0
464
)64
95
(64
61)minus
654
1(minus
646
4)0
306
(02
99)
37P
orto
Ron
cado
rminus
135
8minus
553
2A
NE
EL
2257
127
712
021
412
970
363
(03
63)
100
3(1
002
)40
69
(40
64)minus
860
1(minus
857
6)0
392
(03
93)
38Lu
cas
minus13
15
minus56
05
AN
EE
L26
111
560
50
181
1212
025
2(0
247
)0
971
(09
46)
455
2(4
581
)minus3
541
(minus3
598)
minus0
143
(minus0
155)
39B
arra
gem
Jusa
nte
minus12
78
minus54
27
AN
EE
L16
148
016
540
328
1921
022
4(0
219
)0
987
(09
91)
403
1(4
086
)minus1
711
(minus1
787)
minus0
342
(minus0
350)
40F
azen
daP
aqui
raminus
042
minus53
72
AN
EE
L23
2415
693
84
930
4435
007
9(0
079
)0
997
(10
01)
139
77(1
406
4)minus
924
42(minus
936
09)
004
2(0
042
)41
Por
toVe
lho
minus8
76minus
639
1R
ivD
IS11
3753
1753
938
975
327
1706
454
381
093
2(0
824
)0
094
(01
27)
184
4(2
896
)0
603
(00
20)
093
2(0
737
)42
Obi
dos
minus1
91minus
555
5N
A56
7151
715
603
624
600
030
567
148
176
294
334
091
1(0
626
)0
994
(09
95)
179
2(3
843
)0
527
(minus
117
7)0
880
(04
32)
43Lo
cota
lminus
170
4minus
660
2R
ivD
IS4
412
440
513
00
352
(03
52)
100
9(1
009
)53
35
(53
43)minus
499
4(minus
501
2)0
192
(01
92)
44A
ngos
tode
lBal
aminus
145
5minus
675
5R
ivD
IS4
404
2313
8614
1151
918
590
562
(05
62)
019
8(1
008
)28
74
(28
76)minus
041
3(minus
041
5)0
884
(08
84)
45V
illa
Bar
rient
osminus
163
2minus
672
5R
ivD
IS4
1578
252
047
227
085
4(0
854
)0
188
(01
87)
207
2(2
068
)0
506
(05
08)
083
7(0
838
)46
Alta
mira
minus3
2minus
522
1R
ivD
IS4
1007
8610
2698
414
614
394
4621
20
813
(07
26)
007
0(0
132
)35
52
(42
60)
minus0
538
(minus1
212)
090
8(0
748
)
1W
illm
ott(
1982
)ra
nge
1ndash0
perf
ectm
atch
(pm
)is
12
Jach
ner
etal
(20
07)
0ndashinfinp
mi
s0
3M
ayer
and
But
ler
(199
3)0
ndashinfinp
mi
s0
N-R
SM
E=10
0(R
SM
E(
obs m
ax-o
bsm
in)
4N
ash
and
Sut
cliff
e(1
970)
minusinfin
ndash1p
mi
s1
5se
ee
gJa
chne
ret
al(
2007
)minus
1ndash0ndash
1p
mi
s1
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2252 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
39
40
41
42
Figure 3 Observed and simulated discharge [m3 s
minus1] for all 44 sites Observed 826
discharge as solid grey line simulated discharge with routing velocity of 10 ms-1
as 827
dashed grey line and simulated discharge with slope depending routing velocity as 828
solid black line 829
830
Fig 3 Observed and simulated discharge [m3 sminus1] for all 44 sites Observed discharge as solid grey line simulated discharge with routingvelocity of 10 msminus1 as dashed grey line and simulated discharge with slope depending routing velocity as solid black line
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
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F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
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2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2250 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Table 4 List of the 24 IPCC coupled general circulation models(GCMs) used in this study Details for the climate models see IPCC2007 AR4 chapter 8 (Randall et al 2007)
Model name
BCCR ndash BCM 20 INGV ndash SXGCCCMA ndash CGCM 31 (T47) INM ndash CM 30CCCMA ndash CGCM 31 (T63) IPSL ndash CM 4CNRM ndash CM 3 MIROC 32 (hires)CSIRO ndash Mk 30 MIROC 32 (medres)CSIRO ndash Mk 35 MIUB ndash ECHO-GGFDL ndash CM 20 MPI ndash ECHAM 5GFDL ndash CM 21 MRI ndash CGCM 232aGISS ndash AOM NCAR ndash CCSM 3GISS ndash EH NCAR ndash PCM 1GISS ndash ER UKMO ndash HadCM 3FGOALS ndash g 10 UKMO ndash HadGEM 1
Fig 1 Simulated mean discharge [log m3 sminus1] during June aver-aged over the reference period 1961ndash1990 The white crosses indi-cate the exaple sites Cruzeiro do Sul (CdS ID 3) Porto Velho (PVID 41) andObidos (Obi ID 10 and 42)
and aspect which can be calculated from the DEM We usethe resulting landform type valley flats as potentially flood-able area
In our study mTRMI is the sum of classified slope classi-fied slope configuration and classified relative slope position(Eq 2 see below for definitions)
mTRMI = Sclass+ Sconfigclass+ Sposclass
(2)
We neglect aspect because differences between north andsouth facing slopes are insignificant in the tropics (compareto Donnegan et al 2007) A detailed description of the calcu-lation of mTRMI summands can be found in the Supplement
The first summand is classified slope (Eq 2Sclass) Weuse the previously calculated slope values and slice them insix slope classes (Table 1)
38
823
Figure 2 The 44 sites used for comparison of observed and simulated discharge 824
825
Fig 2The 44 sites used for comparison of observed and simulateddischarge
The second summand is classified slope configuration(Eq 2Sconfclass) Slope configuration describes the convex-ity or concavity of the land surrounding any grid cell basedon the change in elevationZ [m] from cellij to all cells lo-cated at the edge of the 5times 5 cell window We slice the fullrange of resulting values equally into 10 parts and assignthese parts into 3 slope configuration classes slices 0ndash4 toclassminus1 (convex topography) slice 5 to class 0 (flat topog-raphy) slices 6ndash10 to class 1 (concave topography)
The third summand is relative slope position (Eq 2Sposclass
) describing the distance of the cellij to the closestridges and streams We assign the distance [cells] to 6 relativeslope position classes (Table 2)
From the slope classes (Eqs S1ndashS3) the slope configu-ration classes (Eqs S5ndashS9) and the relative slope positionclasses (Eqs S10ndashS11) we calculate mTRMI (Eq 2) Wesum up classified slope (0 to 5) classified slope configura-tion (minus1 to 1) and classified relative slope position (10 to22) The mTRMI ranges from dry to wet (9 to 28) describingsite conditions
We generate a map (15 arc seconds resolution) of landformtypes by combining slopeS and mTRMI For this purpose wegroup sites with defined mTRMI and slope to certain land-form types (details in Table 3) Finally we use the landformtype valley flat which is potentially floodable area to cal-culate the fraction [] of floodable area for each 05times 05
grid cellWe then calculate the fraction of continuously flooded area
from the potentially floodable area (per 05times 05 cell) fromthe work of Richey et al (2002) They estimated that duringlow water stage about 4 and during high water stage about16 of a 177 million km2 quadrant of the central Ama-zon Basin is covered with water This means that 25 of
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2251
Tabl
e5
Com
paris
onof
obse
rved
and
sim
ulat
eddi
scha
rge
for
the
obse
rvat
ion
perio
d(s
eeal
soF
igs
3an
d4)
Ind
ices
are
give
nfo
rth
est
anda
rdsi
mul
atio
n(s
td)
with
slop
ede
pend
ent
rout
ing
velo
city
and
orig
inal
setti
ng(1
0m
sminus
1)
with
hom
ogen
eous
rout
ing
velo
city
of1
0m
sminus
1in
brac
kets
IDS
tatio
nLa
titud
eLo
ngitu
deD
atab
ase
Num
ber
ofob
sye
ars
Obs
erve
dm
inan
nual
disc
harg
e[m
3sminus
1]
Obs
erve
dm
ean
annu
aldi
scha
rge
[m3
sminus1]
Obs
erve
dm
axan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
inan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
ean
annu
aldi
scha
rge
[m3
sminus1]
Sim
ulat
edm
axan
nual
disc
harg
e[m
3sminus
1]
Will
mot
trsquosin
dex
ofag
reem
ent1st
d(1
0m
sminus1)
Err
orof
Qua
lV2
std
(10
msminus
1)
N-R
MS
E3[
]st
d(1
0m
sminus1)
Nas
hndashS
utcl
iffe4
std
(10
msminus
1)
Pea
rson
corr
elat
ion
coef
ficie
nt5st
d(1
0m
sminus1)
1E
stira
odo
Rep
ouso
minus4
37minus
709
3A
NE
EL
1619
325
1847
4915
525
9272
700
870
(07
93)
100
3(0
367
)21
27
(27
75)
037
0(
minus0
073)
079
1(0
678
)2
Sao
Pau
lode
Oliv
enca
minus3
47minus
687
5A
NE
EL
2315
272
4644
278
410
4013
2627
055
717
060
3(0
590
)0
322
(09
56)
347
0(3
596
)minus
136
0(minus
153
5)0
801
(06
94)
3C
ruze
irodo
Sul
minus7
62minus
726
7A
NE
EL
2975
907
2992
2411
0644
890
880
(08
48)
026
3(0
998
)19
68
(22
75)
036
6(0
153
)0
839
(07
96)
4G
avia
ominus
483
minus66
75
AN
EE
L23
603
4732
9932
151
5683
1786
80
855
(07
54)
096
4(0
993
)29
05
(36
94)
013
1(
minus0
405)
082
6(0
652
)5
Aca
naui
minus1
8minus
665
5A
NE
EL
2329
0013
778
2553
329
5511
611
2588
20
693
(06
12)
099
1(0
953
)22
26
(25
51)
minus0
120
(minus0
471)
051
4(0
358
)6
Flo
riano
Pei
xoto
minus9
05minus
673
8A
NE
EL
3027
583
2062
881
335
790
835
(07
93)
024
5(0
974
)26
45
(30
32)
000
7(
minus0
305)
081
0(0
751
)7
Labr
eaminus
725
minus64
8A
NE
EL
3072
354
4411
739
101
6241
2279
90
867
(07
71)
099
3(0
991
)30
60
(40
14)
023
2(
minus0
321)
082
5(0
666
)8
Ser
rinha
minus0
45minus
648
3A
NE
EL
2035
9915
980
3043
434
8615
975
3567
60
910
(08
12)
029
1(1
002
)13
71
(20
37)
064
9(0
225
)0
832
(06
68)
9C
arac
arai
18
minus61
13
AN
EE
L30
244
2898
1117
816
3681
1739
60
868
(08
13)
100
1(0
995
)21
22
(25
95)
015
0(
minus0
271)
086
7(0
790
)10
Obi
dos
minus1
9minus
555
05A
NE
EL
2875
602
172
696
306
318
4275
814
783
429
433
40
873
(06
13)
099
6(0
995
)17
08
(30
76)
035
6(
minus1
090)
086
8(0
426
)11
Por
todo
sG
auch
osminus
116
5minus
572
3A
NE
EL
2233
376
217
021
1077
4248
054
7(0
501
)0
986
(09
45)
714
9(7
786
)minus8
188
(minus9
899)
073
8(0
663
)12
Cac
hoei
rao
minus11
75
minus55
77
AN
EE
L20
224
815
2287
214
4364
340
541
(05
00)
024
6(0
962
)68
39
(73
59)minus
894
9(minus
105
22)
078
3(0
716
)13
Inde
cominus
101
3minus
554
2A
NE
EL
2037
011
4834
650
685
3899
074
2(0
735
)0
304
(10
02)
240
5(2
450
)minus0
200
(minus0
245)
067
4(0
659
)14
Tre
sM
aria
sminus
763
minus57
88
AN
EE
L15
429
3759
1036
59
5801
2244
40
715
(06
60)
098
4(0
966
)44
81
(49
23)minus
202
1(minus
264
7)0
791
(06
93)
15Ja
toba
minus5
15minus
568
3A
NE
EL
2236
4910
790
2633
430
1448
948
219
077
6(0
729
)0
996
(09
89)
414
8(4
512
)minus
125
5(minus
166
9)0
872
(07
75)
16S
aoF
elix
doX
ingu
minus6
58minus
520
5A
NE
EL
2369
750
8821
660
979
6331
724
072
4(0
646
)0
324
(09
50)
295
7(3
340
)minus1
331
(minus1
974)
075
5(0
618
)17
Bel
oH
oriz
onte
minus5
38minus
528
8A
NE
EL
2275
952
3218
818
2085
4234
269
075
1(0
673
)0
995
(10
02)
362
4(4
126
)minus1
518
(minus2
263)
086
2(0
717
)18
Mou
thminus
572
minus54
43
AN
EE
L23
3989
734
6812
2468
8961
054
0(0
483
)0
211
(10
00)
673
2(7
289
)minus7
068
(minus8
460)
077
6(0
659
)19
Ped
rado
Ominus
457
minus54
05
AN
EE
L19
7125
5710
241
2744
4015
755
077
3(0
700
)0
988
(10
02)
319
3(3
690
)minus0
590
(minus1
123)
078
7(0
669
)20
Alta
mira
minus3
2minus
522
2A
NE
EL
2780
886
0932
298
9114
232
5187
70
798
(07
19)
098
1(0
998
)30
75
(35
75)minus0
578
(minus1
132)
086
1(0
714
)21
Sao
Fel
ipe
057
minus67
32
AN
EE
L19
1220
7406
1700
074
965
6018
057
087
7(0
814
)0
979
(09
72)
150
6(1
910
)0
572
(03
12)
079
9(0
684
)22
Uar
acu
055
minus69
17
AN
EE
L20
159
2459
5835
156
2675
6955
087
5(0
834
)0
991
(03
85)
166
4(1
957
)0
497
(03
04)
078
3(0
717
)23
Moc
idad
e3
45minus
610
5A
NE
EL
1316
213
0446
522
1291
7795
075
6(0
785
)0
494
(04
73)
255
2(2
346
)minus0
387
(minus0
172)
065
1(0
682
)24
Mal
oca
doC
onta
ominus
395
minus60
43
AN
EE
L23
3027
795
24
113
519
026
8(0
268
)0
997
(09
89)
325
2(3
252
)minus1
936
(minus1
936)
minus0
437
(minus0
437)
25M
ato
Gro
sso
minus15
02
minus59
97
AN
EE
L27
117
171
20
166
1029
073
5(0
724
)0
983
(10
02)
261
9(2
687
)minus0
152
(minus0
213)
056
0(0
544
)26
Pal
mei
ral
minus10
03
minus64
45
AN
EE
L12
121
486
10
200
767
083
1(0
831)
027
7(0
993
)18
73
(18
74)
039
7(0
397
)0
701
(07
01)
27A
rique
mes
minus10
03
minus62
97
AN
EE
L11
2832
211
350
123
474
061
0(0
610
)0
264
(02
63)
262
4(2
622
)minus0
201
(minus0
198)
062
2(0
623
)28
Sao
Car
los
minus9
7minus
631
3A
NE
EL
1244
341
1338
064
523
640
596
(05
92)
026
1(0
986
)46
42
(46
77)minus
326
0(minus
332
5)0
599
(05
90)
29C
acho
eira
doS
amue
lminus
905
minus63
47
AN
EE
L4
8626
011
332
636
2247
043
1(0
409
)0
581
(09
98)
616
2(6
384
)minus8
788
(minus9
506)
057
5(0
544
)30
San
taIs
abel
minus9
1minus
637
2A
NE
EL
1745
206
624
035
113
810
684
(06
76)
024
7(0
988
)48
26
(48
93)minus
298
1(minus
309
3)0
835
(08
23)
31C
acho
eira
Prim
aver
aminus
119
minus61
23
AN
EE
L19
9414
2942
801
508
2217
061
1(0
610
)0
967
(08
64)
320
2(3
209
)minus0
189
(minus0
193)
064
8(0
641
)32
Pim
enta
Bue
nominus
116
5minus
612
AN
EE
L24
2242
416
071
499
2217
078
6(0
784
)1
002
(09
91)
260
4(2
623
)minus0
028
(minus0
043)
065
4(0
649
)33
Boc
ado
Gua
riba
minus7
68minus
603
AN
EE
L29
4854
6531
070
618
6463
450
572
(05
60)
097
9(0
983
)17
78
(18
11)minus
013
5(minus
017
7)0
692
(06
17)
34S
anta
rem
Suc
undu
riminus
675
minus58
95
AN
EE
L22
013
183
96
980
3398
011
8(0
114
)0
992
(09
72)
151
23(1
520
7)minus
566
89(minus
573
31)
minus0
027
(minus0
041)
35E
stira
oda
Ang
elic
aminus
097
minus57
07
AN
EE
L22
1125
496
91
367
2211
049
8(0
498
)0
566
(09
97)
436
7(4
384
)minus2
819
(minus2
848)
034
0(0
342
)36
Boc
ado
Infe
rno
minus1
57minus
548
3A
NE
EL
1688
362
1257
361
330
110
385
(03
82)
046
6(0
464
)64
95
(64
61)minus
654
1(minus
646
4)0
306
(02
99)
37P
orto
Ron
cado
rminus
135
8minus
553
2A
NE
EL
2257
127
712
021
412
970
363
(03
63)
100
3(1
002
)40
69
(40
64)minus
860
1(minus
857
6)0
392
(03
93)
38Lu
cas
minus13
15
minus56
05
AN
EE
L26
111
560
50
181
1212
025
2(0
247
)0
971
(09
46)
455
2(4
581
)minus3
541
(minus3
598)
minus0
143
(minus0
155)
39B
arra
gem
Jusa
nte
minus12
78
minus54
27
AN
EE
L16
148
016
540
328
1921
022
4(0
219
)0
987
(09
91)
403
1(4
086
)minus1
711
(minus1
787)
minus0
342
(minus0
350)
40F
azen
daP
aqui
raminus
042
minus53
72
AN
EE
L23
2415
693
84
930
4435
007
9(0
079
)0
997
(10
01)
139
77(1
406
4)minus
924
42(minus
936
09)
004
2(0
042
)41
Por
toVe
lho
minus8
76minus
639
1R
ivD
IS11
3753
1753
938
975
327
1706
454
381
093
2(0
824
)0
094
(01
27)
184
4(2
896
)0
603
(00
20)
093
2(0
737
)42
Obi
dos
minus1
91minus
555
5N
A56
7151
715
603
624
600
030
567
148
176
294
334
091
1(0
626
)0
994
(09
95)
179
2(3
843
)0
527
(minus
117
7)0
880
(04
32)
43Lo
cota
lminus
170
4minus
660
2R
ivD
IS4
412
440
513
00
352
(03
52)
100
9(1
009
)53
35
(53
43)minus
499
4(minus
501
2)0
192
(01
92)
44A
ngos
tode
lBal
aminus
145
5minus
675
5R
ivD
IS4
404
2313
8614
1151
918
590
562
(05
62)
019
8(1
008
)28
74
(28
76)minus
041
3(minus
041
5)0
884
(08
84)
45V
illa
Bar
rient
osminus
163
2minus
672
5R
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1578
252
047
227
085
4(0
854
)0
188
(01
87)
207
2(2
068
)0
506
(05
08)
083
7(0
838
)46
Alta
mira
minus3
2minus
522
1R
ivD
IS4
1007
8610
2698
414
614
394
4621
20
813
(07
26)
007
0(0
132
)35
52
(42
60)
minus0
538
(minus1
212)
090
8(0
748
)
1W
illm
ott(
1982
)ra
nge
1ndash0
perf
ectm
atch
(pm
)is
12
Jach
ner
etal
(20
07)
0ndashinfinp
mi
s0
3M
ayer
and
But
ler
(199
3)0
ndashinfinp
mi
s0
N-R
SM
E=10
0(R
SM
E(
obs m
ax-o
bsm
in)
4N
ash
and
Sut
cliff
e(1
970)
minusinfin
ndash1p
mi
s1
5se
ee
gJa
chne
ret
al(
2007
)minus
1ndash0ndash
1p
mi
s1
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2252 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
39
40
41
42
Figure 3 Observed and simulated discharge [m3 s
minus1] for all 44 sites Observed 826
discharge as solid grey line simulated discharge with routing velocity of 10 ms-1
as 827
dashed grey line and simulated discharge with slope depending routing velocity as 828
solid black line 829
830
Fig 3 Observed and simulated discharge [m3 sminus1] for all 44 sites Observed discharge as solid grey line simulated discharge with routingvelocity of 10 msminus1 as dashed grey line and simulated discharge with slope depending routing velocity as solid black line
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
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2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
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Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
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Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
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Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2251
Tabl
e5
Com
paris
onof
obse
rved
and
sim
ulat
eddi
scha
rge
for
the
obse
rvat
ion
perio
d(s
eeal
soF
igs
3an
d4)
Ind
ices
are
give
nfo
rth
est
anda
rdsi
mul
atio
n(s
td)
with
slop
ede
pend
ent
rout
ing
velo
city
and
orig
inal
setti
ng(1
0m
sminus
1)
with
hom
ogen
eous
rout
ing
velo
city
of1
0m
sminus
1in
brac
kets
IDS
tatio
nLa
titud
eLo
ngitu
deD
atab
ase
Num
ber
ofob
sye
ars
Obs
erve
dm
inan
nual
disc
harg
e[m
3sminus
1]
Obs
erve
dm
ean
annu
aldi
scha
rge
[m3
sminus1]
Obs
erve
dm
axan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
inan
nual
disc
harg
e[m
3sminus
1]
Sim
ulat
edm
ean
annu
aldi
scha
rge
[m3
sminus1]
Sim
ulat
edm
axan
nual
disc
harg
e[m
3sminus
1]
Will
mot
trsquosin
dex
ofag
reem
ent1st
d(1
0m
sminus1)
Err
orof
Qua
lV2
std
(10
msminus
1)
N-R
MS
E3[
]st
d(1
0m
sminus1)
Nas
hndashS
utcl
iffe4
std
(10
msminus
1)
Pea
rson
corr
elat
ion
coef
ficie
nt5st
d(1
0m
sminus1)
1E
stira
odo
Rep
ouso
minus4
37minus
709
3A
NE
EL
1619
325
1847
4915
525
9272
700
870
(07
93)
100
3(0
367
)21
27
(27
75)
037
0(
minus0
073)
079
1(0
678
)2
Sao
Pau
lode
Oliv
enca
minus3
47minus
687
5A
NE
EL
2315
272
4644
278
410
4013
2627
055
717
060
3(0
590
)0
322
(09
56)
347
0(3
596
)minus
136
0(minus
153
5)0
801
(06
94)
3C
ruze
irodo
Sul
minus7
62minus
726
7A
NE
EL
2975
907
2992
2411
0644
890
880
(08
48)
026
3(0
998
)19
68
(22
75)
036
6(0
153
)0
839
(07
96)
4G
avia
ominus
483
minus66
75
AN
EE
L23
603
4732
9932
151
5683
1786
80
855
(07
54)
096
4(0
993
)29
05
(36
94)
013
1(
minus0
405)
082
6(0
652
)5
Aca
naui
minus1
8minus
665
5A
NE
EL
2329
0013
778
2553
329
5511
611
2588
20
693
(06
12)
099
1(0
953
)22
26
(25
51)
minus0
120
(minus0
471)
051
4(0
358
)6
Flo
riano
Pei
xoto
minus9
05minus
673
8A
NE
EL
3027
583
2062
881
335
790
835
(07
93)
024
5(0
974
)26
45
(30
32)
000
7(
minus0
305)
081
0(0
751
)7
Labr
eaminus
725
minus64
8A
NE
EL
3072
354
4411
739
101
6241
2279
90
867
(07
71)
099
3(0
991
)30
60
(40
14)
023
2(
minus0
321)
082
5(0
666
)8
Ser
rinha
minus0
45minus
648
3A
NE
EL
2035
9915
980
3043
434
8615
975
3567
60
910
(08
12)
029
1(1
002
)13
71
(20
37)
064
9(0
225
)0
832
(06
68)
9C
arac
arai
18
minus61
13
AN
EE
L30
244
2898
1117
816
3681
1739
60
868
(08
13)
100
1(0
995
)21
22
(25
95)
015
0(
minus0
271)
086
7(0
790
)10
Obi
dos
minus1
9minus
555
05A
NE
EL
2875
602
172
696
306
318
4275
814
783
429
433
40
873
(06
13)
099
6(0
995
)17
08
(30
76)
035
6(
minus1
090)
086
8(0
426
)11
Por
todo
sG
auch
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116
5minus
572
3A
NE
EL
2233
376
217
021
1077
4248
054
7(0
501
)0
986
(09
45)
714
9(7
786
)minus8
188
(minus9
899)
073
8(0
663
)12
Cac
hoei
rao
minus11
75
minus55
77
AN
EE
L20
224
815
2287
214
4364
340
541
(05
00)
024
6(0
962
)68
39
(73
59)minus
894
9(minus
105
22)
078
3(0
716
)13
Inde
cominus
101
3minus
554
2A
NE
EL
2037
011
4834
650
685
3899
074
2(0
735
)0
304
(10
02)
240
5(2
450
)minus0
200
(minus0
245)
067
4(0
659
)14
Tre
sM
aria
sminus
763
minus57
88
AN
EE
L15
429
3759
1036
59
5801
2244
40
715
(06
60)
098
4(0
966
)44
81
(49
23)minus
202
1(minus
264
7)0
791
(06
93)
15Ja
toba
minus5
15minus
568
3A
NE
EL
2236
4910
790
2633
430
1448
948
219
077
6(0
729
)0
996
(09
89)
414
8(4
512
)minus
125
5(minus
166
9)0
872
(07
75)
16S
aoF
elix
doX
ingu
minus6
58minus
520
5A
NE
EL
2369
750
8821
660
979
6331
724
072
4(0
646
)0
324
(09
50)
295
7(3
340
)minus1
331
(minus1
974)
075
5(0
618
)17
Bel
oH
oriz
onte
minus5
38minus
528
8A
NE
EL
2275
952
3218
818
2085
4234
269
075
1(0
673
)0
995
(10
02)
362
4(4
126
)minus1
518
(minus2
263)
086
2(0
717
)18
Mou
thminus
572
minus54
43
AN
EE
L23
3989
734
6812
2468
8961
054
0(0
483
)0
211
(10
00)
673
2(7
289
)minus7
068
(minus8
460)
077
6(0
659
)19
Ped
rado
Ominus
457
minus54
05
AN
EE
L19
7125
5710
241
2744
4015
755
077
3(0
700
)0
988
(10
02)
319
3(3
690
)minus0
590
(minus1
123)
078
7(0
669
)20
Alta
mira
minus3
2minus
522
2A
NE
EL
2780
886
0932
298
9114
232
5187
70
798
(07
19)
098
1(0
998
)30
75
(35
75)minus0
578
(minus1
132)
086
1(0
714
)21
Sao
Fel
ipe
057
minus67
32
AN
EE
L19
1220
7406
1700
074
965
6018
057
087
7(0
814
)0
979
(09
72)
150
6(1
910
)0
572
(03
12)
079
9(0
684
)22
Uar
acu
055
minus69
17
AN
EE
L20
159
2459
5835
156
2675
6955
087
5(0
834
)0
991
(03
85)
166
4(1
957
)0
497
(03
04)
078
3(0
717
)23
Moc
idad
e3
45minus
610
5A
NE
EL
1316
213
0446
522
1291
7795
075
6(0
785
)0
494
(04
73)
255
2(2
346
)minus0
387
(minus0
172)
065
1(0
682
)24
Mal
oca
doC
onta
ominus
395
minus60
43
AN
EE
L23
3027
795
24
113
519
026
8(0
268
)0
997
(09
89)
325
2(3
252
)minus1
936
(minus1
936)
minus0
437
(minus0
437)
25M
ato
Gro
sso
minus15
02
minus59
97
AN
EE
L27
117
171
20
166
1029
073
5(0
724
)0
983
(10
02)
261
9(2
687
)minus0
152
(minus0
213)
056
0(0
544
)26
Pal
mei
ral
minus10
03
minus64
45
AN
EE
L12
121
486
10
200
767
083
1(0
831)
027
7(0
993
)18
73
(18
74)
039
7(0
397
)0
701
(07
01)
27A
rique
mes
minus10
03
minus62
97
AN
EE
L11
2832
211
350
123
474
061
0(0
610
)0
264
(02
63)
262
4(2
622
)minus0
201
(minus0
198)
062
2(0
623
)28
Sao
Car
los
minus9
7minus
631
3A
NE
EL
1244
341
1338
064
523
640
596
(05
92)
026
1(0
986
)46
42
(46
77)minus
326
0(minus
332
5)0
599
(05
90)
29C
acho
eira
doS
amue
lminus
905
minus63
47
AN
EE
L4
8626
011
332
636
2247
043
1(0
409
)0
581
(09
98)
616
2(6
384
)minus8
788
(minus9
506)
057
5(0
544
)30
San
taIs
abel
minus9
1minus
637
2A
NE
EL
1745
206
624
035
113
810
684
(06
76)
024
7(0
988
)48
26
(48
93)minus
298
1(minus
309
3)0
835
(08
23)
31C
acho
eira
Prim
aver
aminus
119
minus61
23
AN
EE
L19
9414
2942
801
508
2217
061
1(0
610
)0
967
(08
64)
320
2(3
209
)minus0
189
(minus0
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064
8(0
641
)32
Pim
enta
Bue
nominus
116
5minus
612
AN
EE
L24
2242
416
071
499
2217
078
6(0
784
)1
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(09
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260
4(2
623
)minus0
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(minus0
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065
4(0
649
)33
Boc
ado
Gua
riba
minus7
68minus
603
AN
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L29
4854
6531
070
618
6463
450
572
(05
60)
097
9(0
983
)17
78
(18
11)minus
013
5(minus
017
7)0
692
(06
17)
34S
anta
rem
Suc
undu
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675
minus58
95
AN
EE
L22
013
183
96
980
3398
011
8(0
114
)0
992
(09
72)
151
23(1
520
7)minus
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89(minus
573
31)
minus0
027
(minus0
041)
35E
stira
oda
Ang
elic
aminus
097
minus57
07
AN
EE
L22
1125
496
91
367
2211
049
8(0
498
)0
566
(09
97)
436
7(4
384
)minus2
819
(minus2
848)
034
0(0
342
)36
Boc
ado
Infe
rno
minus1
57minus
548
3A
NE
EL
1688
362
1257
361
330
110
385
(03
82)
046
6(0
464
)64
95
(64
61)minus
654
1(minus
646
4)0
306
(02
99)
37P
orto
Ron
cado
rminus
135
8minus
553
2A
NE
EL
2257
127
712
021
412
970
363
(03
63)
100
3(1
002
)40
69
(40
64)minus
860
1(minus
857
6)0
392
(03
93)
38Lu
cas
minus13
15
minus56
05
AN
EE
L26
111
560
50
181
1212
025
2(0
247
)0
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(09
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455
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(minus3
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(minus0
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minus12
78
minus54
27
AN
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L16
148
016
540
328
1921
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4(0
219
)0
987
(09
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403
1(4
086
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(minus1
787)
minus0
342
(minus0
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40F
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raminus
042
minus53
72
AN
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L23
2415
693
84
930
4435
007
9(0
079
)0
997
(10
01)
139
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42(minus
936
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2(0
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)41
Por
toVe
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minus8
76minus
639
1R
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3753
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938
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327
1706
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381
093
2(0
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(01
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184
4(2
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)0
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(00
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093
2(0
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Obi
dos
minus1
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555
5N
A56
7151
715
603
624
600
030
567
148
176
294
334
091
1(0
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)0
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(09
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179
2(3
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(minus
117
7)0
880
(04
32)
43Lo
cota
lminus
170
4minus
660
2R
ivD
IS4
412
440
513
00
352
(03
52)
100
9(1
009
)53
35
(53
43)minus
499
4(minus
501
2)0
192
(01
92)
44A
ngos
tode
lBal
aminus
145
5minus
675
5R
ivD
IS4
404
2313
8614
1151
918
590
562
(05
62)
019
8(1
008
)28
74
(28
76)minus
041
3(minus
041
5)0
884
(08
84)
45V
illa
Bar
rient
osminus
163
2minus
672
5R
ivD
IS4
1578
252
047
227
085
4(0
854
)0
188
(01
87)
207
2(2
068
)0
506
(05
08)
083
7(0
838
)46
Alta
mira
minus3
2minus
522
1R
ivD
IS4
1007
8610
2698
414
614
394
4621
20
813
(07
26)
007
0(0
132
)35
52
(42
60)
minus0
538
(minus1
212)
090
8(0
748
)
1W
illm
ott(
1982
)ra
nge
1ndash0
perf
ectm
atch
(pm
)is
12
Jach
ner
etal
(20
07)
0ndashinfinp
mi
s0
3M
ayer
and
But
ler
(199
3)0
ndashinfinp
mi
s0
N-R
SM
E=10
0(R
SM
E(
obs m
ax-o
bsm
in)
4N
ash
and
Sut
cliff
e(1
970)
minusinfin
ndash1p
mi
s1
5se
ee
gJa
chne
ret
al(
2007
)minus
1ndash0ndash
1p
mi
s1
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2252 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
39
40
41
42
Figure 3 Observed and simulated discharge [m3 s
minus1] for all 44 sites Observed 826
discharge as solid grey line simulated discharge with routing velocity of 10 ms-1
as 827
dashed grey line and simulated discharge with slope depending routing velocity as 828
solid black line 829
830
Fig 3 Observed and simulated discharge [m3 sminus1] for all 44 sites Observed discharge as solid grey line simulated discharge with routingvelocity of 10 msminus1 as dashed grey line and simulated discharge with slope depending routing velocity as solid black line
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2252 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
39
40
41
42
Figure 3 Observed and simulated discharge [m3 s
minus1] for all 44 sites Observed 826
discharge as solid grey line simulated discharge with routing velocity of 10 ms-1
as 827
dashed grey line and simulated discharge with slope depending routing velocity as 828
solid black line 829
830
Fig 3 Observed and simulated discharge [m3 sminus1] for all 44 sites Observed discharge as solid grey line simulated discharge with routingvelocity of 10 msminus1 as dashed grey line and simulated discharge with slope depending routing velocity as solid black line
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2253
Table 6Comparison of observed floodplain area and calculated floodable area in the subregions of the basin R denotes the rectangle numberin Fig 5
North-west corner South-east corner
Floodplain
Source R area [103 km2] fraction []
published calculated published calculated
Richey et al (2002) 1 072 W 8 S54 W 2900 2395 163 135Melack et al (2004) 1 072 W 8 S54 W 1903 2395 107 135Hess et al (2003) 1 072 W 8 S54 W 3030 2395 170 135Hamilton et al (2002) 2 2 S70 W 5 S52W 974 914 146 137Hamilton et al (2002) 3 12 S68 W 16 S61 W 921 494 274 147
the high water flooded area is also covered during low waterWe therefore assume that 25 of the potential floodable areais continuously covered with water
Estimations of the inundation with models andor remotesensing has besides Richey et al (2002) already conductedfor example by Alsdorf et al (2007 2010) and Bates andDe Roo (2000) A comparison of remotely sensed inunda-tion and modelled inundation has been conducted by Wilsonet al (2007) and Bates (2012) These studies also discuss theapplicability of modeling and remote sensing to the inunda-tion estimation Due to the high spatial and temporal vari-ability in large catchments these methods are excellent toolsto investigate inundation patterns
The actual monthly flooded area is calculated by assum-ing that under current conditions (reference period 1961ndash1990) the floodable area is totally covered with water if thereference mean of the maximal monthly discharge per year(ie high water stage) plus the standard deviation for this pe-riod is reached Therefore it is possible that more than themaximal floodable area is flooded during anomalously highwater discharge years
22 Data and simulations
LPJmL is run in its natural vegetation mode at 05times 05 spa-tial resolution for the period 1901ndash2099 Transient runs arepreceded by 1000 yr spin up during which the pre-industrialCO2 level of 280 ppm and the climate of the years 1901ndash1930are repeated to obtain equilibrium for vegetation carbon andwater pools
For the model evaluation we perform model runs usingclimate forcing data from a homogenized and extended CRUTS21 global climate dataset covering the years 1901 to 2003(Osterle et al 2003 Mitchell and Jones 2005) For the pro-jections we take climate forcing data from 24 coupled gen-eral circulation models (GCMs Table 4) chosen for the 4thAssessment Report of the IPCC (Nakicenovic et al 2000Meehl et al 2007) calculated under the SRES A1B sce-nario Since all current climate models show considerable bi-ases for the Amazon Basin we apply an anomaly approach(Rammig et al 2010) The anomaly approach determines the
climate model bias for the reference period (1961ndash1990) asthe difference (for temperature) or the ratio (for precipitationand cloud cover) of the 30 yr means of climate model out-put (24 climate projections from IPCC-AR4) and observedclimate (CRU) for each month and each grid cell With thisapproach climate model bias is removed and the climate in-put for LPJmL is standardized (Rammig et al 2010)
To get quasi-daily values the monthly values of tempera-ture and cloud cover are linearly interpolated Daily precipi-tation amount and distribution of wet days to calculate coreprocesses such as photosynthesis water fluxes and vegeta-tion growth are inferred using a stochastic method (Gertenet al 2004) This method of using monthly inputs and recal-culate them to quasi-daily values is used in most large-scalemultiple-scenario studies (Alcamo et al 2003 Biemans etal 2011 Rost et al 2008) Whether the treatment of climatedata with the present implementation of the weather gener-ator in our model significantly affects simulating results rel-ative to the climate change signal is being investigated in anon-going study (Gerten et al 2012) Soil information is de-rived from the FAO global database (FAO 1991 Sitch et al2003)
23 Model evaluation and projections
231 Current conditions
We compare observed monthly discharge from the ldquoRiverDischarge Databaserdquo of the ldquoCenter for Sustainability andthe Global Environmentrdquo (2007) with simulated monthly dis-charge at 44 sites for corresponding time periods Addi-tionally to the simulation with the improved slope depen-dent routing velocity we also compare the simulated dis-charge calculated with the original LPJmL routing velocityof 10 msminus2 This shows the improvement of the introductionof the slope dependent routing velocity The observed andsimulated discharge for the 44 observation sites (Fig 2) areshown in Fig 3 (details in Table 5) We evaluate the qualityof our model simulations with the Willmottrsquos index of agree-ment which ranges from 0 to 1 with 1 indicating completeagreement (Willmott 1982) and the error of the qualitative
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
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Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
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Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
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Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
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2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
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Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2254 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
4
3
8
31
Fig 4 Comparison of observed and simulated discharge for all 44 observation sites with 5 indices (details in Table 5) Sites are sortedaccording the observed mean annual discharge [m3 sminus1] with the lowest discharge site at the left hand site
validation (QualV) which ranges from 0 to infinite with lowvalues indicating high agreement (Jachner et al 2007) Wealso calculate the normalised RMSE NashndashSutcliffe coeffi-cient and Pearson correlation coefficient (Mayer and Butler1993 Nash and Sutcliffe 1970) A summary of these resultsis given in Table 5 and Fig 4
For further evaluation we compare the calculated flood-able area with published values of floodplain area for 3 sub-regions of the basin (Hamilton et al 2002 Richey et al2002 Melack et al 2004 Lehner and Doll 2004 details inTable 6 and Fig 5)
232 Projections
Future changes in inundated area duration of inundation andhigh and low water peak month are evaluated by comparingthe years 1961 to 1990 (reference period) with data from thelast 30 model years 2070 to 2099 (future period) We ex-tend our analysis to identify changes in frequency of extremeevents (ie droughts and very high floods) In this context wedefine ldquoextreme floodrdquo as the flooded area being larger thanthe 30 yr median flooded area added by the standard devi-ation (for the considered time period) We define ldquoextremedroughtrdquo as the flooded area being smaller than the meanflooded area reduced by the standard deviation We calcu-late proportion of models in agreement in certain events bycombining results of the 24 different model runs If all modelruns (2424) show this event the proportion is 100 and 4 if only one model run shows this event
45
836
Figure 5 Fraction classes of floodable area per cell Class 1 representing lt5 class 2 837
representing ge5-10 class 3 representing ge10-15 class 4 representing ge15-45 of 838
floodable area For a comparison of simulated floodable area with floodplain area 839
(rectangles R1ndashR3) see Table 6 840
841
Fig 5 Fraction classes of floodable area per cell Class 1 repre-sentinglt 5 class 2 representingge 5ndash10 class 3 representingge 10ndash15 class 4 representingge 15ndash45 of floodable area For acomparison of simulated floodable area with floodplain area (rect-angles R1ndashR3) see Table 6
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
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2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2255
46
842
Figure 6 Proportion of models in agreement [] in (a) an increase and (b) a decrease 843
of mean annual inundated area per cell The proportion represents the agreement 844
between the 24 model runs showing an increase or a decrease in inundated area 845
respectively 846
847
Fig 6Proportion of models in agreement [] in(a) an increase and(b) a decrease of mean annual inundated area per cell The propor-tion represents the agreement between the 24 model runs showingan increase or a decrease in inundated area respectively
3 Results and discussion
31 Current conditions
311 Routing velocity
The calculated routing velocity is highest in the Andean re-gion where the slopes are steepest and lowest in the depres-sion of the basin (Fig S1) Both the Guiana Highlands andthe Brazilian Highlands (north-west and south of the mouthrespectively) can be identified with a slightly higher veloc-ity than the lowland For the three example sites Cruzeirodo Sul Porto Velho andObidos we calculate routing veloci-ties of 025 msminus1 which agree with those reported by Birkettet al (2002) and Richey et al (1989) who measured a flowvelocity of 035plusmn 005 and 03 msminus1 respectively A sensi-tivity analysis carried out to estimate the effect of alteredR
andk values (Eq 1) on the routing velocity showed that the
47
848
Figure 7 Lengthening (blue) and shortening (red) of duration of inundation in months 849
(mean over 24 model realizations) between future and reference period 850
851
Fig 7Lengthening (blue) and shortening (red) of duration of inun-dation in months (mean over 24 model realisations) between futureand reference period
calculated velocities are less sensitive to changes ink than inR (for details see Fig S2) Depending onk andR the cal-culated basin wide mean velocity ranges between 007 and033 msminus1 while the applied velocity is 025 msminus1
Our model input velocities are calculated using slope me-dians over 05times 05 cells and thereby steep and plane areasare combined which leads to differences between simulatedrouting velocities and the observed flow velocities We areaware that our approach of applying the standard ManningndashStrickler formulation to such large spatial scales is limitedand that information on the parameterisation is missing Weattribute the uncertainty of the parameters by conducting ananalysis to estimate the sensitivity of the routing velocity tok
andR (see Supplement S1) This in combination with the ef-fective reproduction of observed hydrographs (details in Ta-ble 5) confirms that our method is suitable for our simulationpurposes
312 Simulated discharge
For most of the sites the characteristics of the simulated hy-drograph such as time and height of high and low waterphase agree with observed hydrographs (Fig 3 Table 5) Dueto scaling effects the model underestimates however the dis-charge at several sites (Fig 3) These scaling effects may inpart be caused by the averaging out of the high discharge incells that do not fully cover the measured river reach as wellas the false estimation of sites which belong to the same sim-ulated cell This problem could be overcome by applying themodel on a smaller scale or by including a larger amount ofmeasurement data if available to better represent the aver-age discharge of the certain area
In our further analysis of shifts of high and low water peakmonths due to climate change we compare the simulatedpeak month during a reference period with simulated peak
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
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2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2256 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
48
852
Figure 8 Proportion of models in agreement [] in a forward shift (a c) and 853
backward shift (b d) between future and reference period of at least 3-months of high 854
water peak month (a b) and low water peak month (c d) 855
856
Fig 8 Proportion of models in agreement [] in a forward shift(a c) and backward shift(b d) between future and reference period of atleast 3-months of high water peak month(a b) and low water peak month(c d)
months during a future period We are therefore confidentthat the small deviations to earlier peak month in the modelwill not affect the calculated differences between referenceand future period
In our work we simulate the discharge for sites withless than 10 m3 sminus1 as well as sites with more than100 000 m3 sminus1 mean June discharge (see Fig 1) Concern-ing this wide range of discharge within the basin the repro-duction of the overall discharge pattern is unprecedented fora model with predictive capacity We reproduce the order ofmagnitude of discharge and regarding the standard deviationof the observed discharge we see that our model results canreproduce the discharge in low medium and high dischargesites
For the comparison of observed and simulated dischargefor all 44 gauging stations we calculated Willmottrsquos index ofagreement error of qualitative validation normalised RMSENashndashSutcliffe coefficient and the Pearson correlation coef-ficient The wide range of indices offers the possibility tocompare the discharge data under different aspects Four outof the five indices show for most of the sites a high agreementbetween simulated and observed discharge The Willmottrsquos
index of agreement is in 23 of the 44 sites (52 ) larger than07 compare to 18 sites (41 ) simulated with the originalhomogenous routing velocity of 10 msminus1 (Table 5) The er-ror of the QualV is in 18 sites (41 ) smaller than 05 com-pared to 8 sites (18 ) For the three example sites Cruzeirodo Sul Porto Velho andObidos the Willmottrsquos index ofagreement is 088 093 and 091 respectively The error ofQualV for these sites is 026 009 and 099 respectively Ithas to be taken into account that for this analysis the modelwas run in its natural vegetation mode It is known that defor-estation changes the hydrological flows eg due to changesin surface runoff (Foley et al 2007) This might lead to smalldifferences between observed and simulated discharge
313 Floodplain area
A comparison of floodplain area in three part of the basinshows that calculated floodable area agrees with publishedvalues for floodplain area Cells with a high fraction of flood-able area are concentrated along the main stems of the rivernetwork (Fig 5) In addition to the Amazon main stem alarge potentially floodable area is calculated in the south ofthe region (around 15 S 65 W) realistically reproducing
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2257
49
857
Figure 9 Difference of the number of (a) extremely dry years and (b) extremely wet 858
years between future and reference period 859
860
Fig 9 Difference of the number of(a) extremely dry years and(b) extremely wet years between future and reference period
the Llanos de Moxos wetland (upper Rio Madeira basin)This vast area of about 150 000 km2 is inundated annually for3 to 4 months (Hamilton et al 2002) According to Melacket al (2004) about 14 of the whole Amazon Basin is flood-able this agrees with our result of 126 Detailed compari-son with published data for 3 subregions of the basin (rectan-gles R1ndashR3 in Fig 5) with Hamilton et al (2002) Richey etal (2002) Hess et al (2003) and Melack et al (2004) showsthat calculated and observed values are in comparable rangefor 3 of the 4 regions (Fig 5 Table 6) In the central basin(R1 and R2 in Fig 5) our values of floodable area are closeto observed values For R1 the value is in between reportedvalues We underestimate by 174 compared to Richey etal (2002) and by 21 compared to Hess et al (2003) andwe overestimate by 26 compared to Melack et al (2004)For R2 also situated in central Amazonia we underestimatedby 6 in comparison to Hamilton et al (2002) Bigger dif-ferences were found for the Llanos de Moxos (R3) Here weunderestimated the floodable area by about 46 compared to
50
861
Figure 10 Difference in the probability of at least three consecutive extremely dry 862
years (a) and extremely wet years (b) between the future and reference period 863
Fig 10 Difference in the probability of at least three consecutiveextremely dry years(a) and extremely wet years(b) between thefuture and reference period
Hamilton et al (2002) However he and his colleagues exam-ine only the Llanos de Moxos while our rectangular regionalso includes parts outside this area Thus our underestima-tion of the floodable area in this region is probably a result ofthe comparison of two slightly different spatial subsets
The connectivity between floodplain and river depends onsmall-scale characteristics such as small channels We ap-proximate this connectivity on a large-scale of 05 by build-ing our analysis on a high resolution DEM and thus capturesmall-scale characteristics We are aware that this simplifi-cation cannot fully represent the actual characteristics of thefloodplain Studying small scale changes such as the shift offloodplain forest into Terra firme forest of few hundred me-tres would require a much finer resolution but to roughly as-sess the possible changes in floodplain extend this approachis appropriate (see also Guimberteau et al 2012) Howeverthe estimated floodplain area and therewith the inundatedpatterns must be regarded as a first assessment at large spatialscales Our large-scale approach may be applied to various
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2258 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
river catchments where a digital elevation model is availableIt is especially useful for large catchments where measuredvalues are insufficiently available Besides this we can alsoreasonably reproduce floodable area with the approach of themodified TRMI This is a basis to calculate actual inundatedarea which enables us to estimate the extent of the area ofstrong interactions between land and river as this landndashriverinterface is of importance for plant and animal diversity
32 Future inundation patterns
For the Amazon region temperature is projected to increaseby up to 35 K until the end of the century in the A2 scenario(Meehl et al 2007) A decrease of precipitation is expectedby the end of the century (especially during the southern-hemisphere winter) in southern Amazonia whereas an in-crease in precipitation is expected in the northern part (seeeg Rammig et al 2010) Precipitation is of course a di-rect driver for inundation patterns in the Amazon Basin andthus the quality of precipitation projections is crucial for pro-jecting future inundation patterns It is well known that un-til now precipitation projections from General CirculationModels (GCMs) for the Amazon Basin are highly uncertain(eg Jupp et al 2010) mainly due to model uncertaintiesin projecting land surface feedbacks cloud formation andtropical Pacific and Atlantic sea surface temperature changes(eg Li et al 2006) Rowell (2011) found highest uncertain-ties in the deep tropics especially over South America Byapplying the model results of 24 GCMs from the IPCC-AR4we apply here the best available range of future precipitationand temperature projections and we therefore also includethe uncertainties in our results and discussions
Our approach of slope dependent routing velocity success-fully reproduces the hydrograph for the period 1961ndash1990and we therefore compare this period to the projections for2070ndash2099 to estimate changes in inundation patterns
We identify several spatial and temporal shifts in the inun-dation regime under future climate conditions For the west-ern part of Amazonia 60ndash100 of the models agree in dis-playing an increase in inundated area (Fig 6a) For the east-ern part there is no clear trend about half of the modelsproject an increase and half show a decrease in inundationarea with proportions of 50ndash60 and 40ndash60 respectively(Fig 6b) Inundation tends to be lengthened by 2 to 3 monthsin the western basin while in the east a shortening of the in-undation duration is likely to occur on average by 05 to 1months (Fig 7) Furthermore our results indicate that in thenorth-west temporal shifts in the time of high and low wa-ter peak month will occur (Fig 8) But the exact spatial andtemporal dimensions of these changes remain unclear Wecalculate a proportion of models in agreement of 40 to 50 (Fig 8a) for a 3-months-forwards shift of the high water peakmonth in some parts of north-western Amazonia There is asimilar proportion for a 3-months-backwards shift in other
parts of this region (Fig 8b) A comparable pattern can beseen for the low water peak month (Fig 8c and d)
The analysis of extreme years reveals that in a 30 yr periodthe number of extremely dry years decreases by up to 3 yrin north-west and south-east Amazonia (Fig 9a) The pro-portion of models in agreement for 3 consecutive dry yearsdecreases in most parts of Amazonia by 30 to 90 with anespecially pronounced decrease in north-east and south-westAmazonia (Fig 10a) Thus dry years are expected to occurless often and more discrete leading to less predictable con-ditions The analysis of extreme wet years shows changes inthe number ofminus15 to +15 yr (Fig 9b) in a 30 yr periodwith no clear spatial pattern The proportion for 3 consecu-tive years with extreme floods shows spatial differences Itdecreases by up to 70 in the east and it increases by upto 40 in the north-west (Fig 10b) The extreme wet yearspersist longer in the west and are expected to occur morediscrete in eastern Amazonia
4 Conclusions
Under future conditions modifications in flooded area andinundation duration as well as high and low water peakmonths and extreme years are likely to occur Already in thisdecade three years with extraordinary water amounts tookplace (Marengo et al 2008 2011 Nobre and De SimoneBorma 2009) The ldquoCore Amazonrdquo (Killeen and Solorzano2008) in the north-western part of the Amazon Basin ex-periences in our simulations most of these changes An in-crease in inundated area a lengthening of inundation dura-tion changes in low and high water peak month combinedwith shifts in occurrence and duration of extreme events havethe potential to change this region substantially The large-scale changes in floodplain patterns found in this study mayamplify projected climate and land-use change effects Weassume that the shifted flooding situation will influence sev-eral plant and animal species This will lead to changes inspecies composition due to shifts in competition and foodweb networks Since the biodiversity increases from east towest in the Amazon Basin (Worbes 1997 ter Steege et al2003) the predicted changes in the north-western part willinfluence an area with a large and valuable species pool
The projected changes in inundation have to potential forlarge-scale changes in water and carbon fluxes The reduc-tion of terrestrial evapotranspiration caused by an increase ofinundated area and projected deforestation could lead to a re-duced recycling of precipitation and further amplify droughtconditions The South American Low Level Jet is transport-ing atmospheric moisture from the Amazon southwards tothe Parana-La Plata Basin (Marengo et al 2009) A reduc-tion of moisture in Amazonia might therefore reduce the pre-cipitation of the entire region of South America The out-gassing CO2 from the Amazon Basin which is currentlyestimated to be about 470 Tg C yrminus1 (Richey et al 2002)
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
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Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2259
is likely to increase due to longer inundation in the westThe less pronounced shortening of inundation in the eastmight not be sufficiently able to balance the additional fluxChanges in regional climate will significantly change vege-tation patterns in Amazonia and may cause additional carbonemissions We conclude that changes in inundation patternscaused by climate change will significantly alter the highlycomplex system in the Amazon Basin
Supplementary material related to this article isavailable online athttpwwwhydrol-earth-syst-scinet1722472013hess-17-2247-2013-supplementpdf
AcknowledgementsWe thank ldquoPakt fur Forschung der Leibniz-Gemeinschaftrdquo for funding the TRACES project We also thankJohn Lowry from Utah State University for providing AML scripttemplates to calculate mTRMI and landform types We thankHeike Zimmermann-Timm Pia Parolin and Florian Wittmann forfruitful discussion We also thank the anonymous reviewers fortheir helpful remarks Finally we thank our LPJmL and AmazonGroup colleagues at PIK
Edited by A Bronstert
References
Alcamo J Henrichs T and Rosch T World Water in 2025 ndashGlobal modeling and scenario analysis for the World Commis-sion on Water for the 21st Century Report A0002 Center forEnvironmental Systems Research University of Kassel KurtWolters Strasse 3 34109 Kassel Germany 2000
Alsdorf D E Rodrıguez E and Lettenmaier D P Measur-ing surface water from space Rev Geophys 45 RG2002doi1010292006RG000197 2007
Alsdorf D Han S-C Bates P and Melack J Sea-sonal water storage on the Amazon floodplain measuredfrom satellites Remote Sens Environ 114 2448ndash2456doi101016jrse201005020 2010
Anderson L O Malhi Y Ladle R J Aragao L E O CShimabukuro Y Phillips O L Baker T Costa A C L Es-pejo J S Higuchi N Laurance W F Lopez-Gonzalez GMonteagudo A Nunez-Vargas P Peacock J Quesada C Aand Almeida S Influence of landscape heterogeneity on spatialpatterns of wood productivity wood specific density and aboveground biomass in Amazonia Biogeosciences 6 1883ndash1902doi105194bg-6-1883-2009 2009
Arnold J G and Fohrer N SWAT2000 current capabilities andresearch opportunities in applied watershed modelling HydrolProcess 19 563ndash572 doi101002hyp5611 2005
Arora V K and Boer G J Effects of simulated climate changeon the hydrology of major river basins J Geophys Res-Atmos106 3335ndash3348 2001
Bates P D Integrating remote sensing data with flood inundationmodels how far have we got Hydrol Process 26 2515ndash2521doi101002hyp9374 2012
Bates P and De Roo A P A simple raster-based modelfor flood inundation simulation J Hydrol 236 54ndash77doi101016S0022-1694(00)00278-X 2000
Betts R A Malhi Y and Roberts J T The future ofthe Amazon new perspectives from climate ecosystem andsocial sciences Philos T R Soc B 363 1729ndash1735doi101098rstb20080011 2008
Biemans H Hutjes R W A Kabat P Strengers B J GertenD and Rost S Effects of precipitation uncertainty on dischargecalculations for main river basins J Hydrometeorol 10 1011ndash1025 doi1011752008jhm10671 2009
Biemans H Haddeland I Kabat P Ludwig F Hutjes RW A Heinke J Von Bloh W and Gerten D Impactof reservoirs on river discharge and irrigation water supplyduring the 20th century Water Resour Res 47 W03509doi1010292009WR008929 2011
Birkett C M Mertes L A K Dunne T Costa M H and Jasin-ski M J Surface water dynamics in the Amazon Basin Appli-cation of satellite radar altimetry J Geophys Res-Atmos 107261ndash2621 doi1010292001JD000609 2002
Bondeau A Smith P C Zaehle S Schaphoff S LuchtW Cramer W Gerten D Lotze-Campen H Muller CReichstein M and Smith B Modelling the role of agri-culture for the 20th century global terrestrial carbon bal-ance Global Change Biol 13 679ndash706 doi101111j1365-2486200601305x 2007
Burrough P A Digital elevation models in Principles of ge-ographical information systems for land resources assessmentedited by Burrough P A 39ndash55 Oxford University Press NewYork 1986
Center for sustainability and the global environment (SAGE)River Discharge Database available athttpwwwsagewisceduriverdata(last access 12 October 2007) 2007
Coe M T Costa M H Botta A and Birkett C Long-termsimulations of discharge and floods in the Amazon Basin JGeophys Res-Atmos 107 8044 doi1010292001JD0007402002
Cox P M Betts R A Collins M Harris P P HuntingfordC and Jones C D Amazonian forest dieback under climate-carbon cycle projections for the 21st century Theor Appl Cli-matol 78 137ndash156 doi101007s00704-004-0049-4 2004
Doll P and Zhang J Impact of climate change on freshwa-ter ecosystems a global-scale analysis of ecologically relevantriver flow alterations Hydrol Earth Syst Sci 14 783ndash799doi105194hess-14-783-2010 2010
Doll P Kaspar F and Lehner B A global hydrological modelfor deriving water availability indicators model tuning and vali-dation J Hydrol 270 105ndash134 2003
Donnegan J A Butler S L Kuegler O Stroud B J HiseroteB A and Rengulbai K Palaursquos forest resources 2003 in Re-sour Bull PNW-RB-252 1ndash52 US Department of AgricultureForest Service Pacific Northwest Research Station PortlandOR 2007
FAO The digitized soil map of the world (Release 10) Food andAgriculture Organization of the United Nations Rome Italy1991
Fearnside P M Are climate change impacts already affectingtropical forest biomass Global Environ Chang 14 299ndash302doi101016jgloenvcha200402001 2004
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2260 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
Fekete B M Vorosmarty C J and Grabs W Global com-posite runoff fields of observed river discharge and simulatedwater balances Global Runoff Data Center Koblenz availableat httpwwwbafgdenn298486GRDCEN02Services04 Report Seriesreport22templateId=rawproperty=publicationFilepdfreport22pdf 1999
Foley J A Botta A Coe M T and Costa M H ElNino-Southern Oscillation and the climate ecosystems andrivers of Amazonia Global Biogeochem Cy 16 791ndash7917doi1010292002GB001872 2002
Foley J A Asner G P Costa M H Coe M T DeFriesR Gibbs H K Howard E A Olson S Patz J Ra-mankutty N and Snyder P Amazonia revealed forest degra-dation and loss of ecosystem goods and services in the Ama-zon Basin Front Ecol Environ 5 25ndash32 doi1018901540-9295(2007)5[25ARFDAL]20CO2 2007
Gaillardet J Dupre B Allegre C J and Negrel P Chemical andphysical denudation in the Amazon River basin Chem Geol142 141ndash173 1997
Gerten D Schaphoff S Haberlandt U Lucht W and Sitch STerrestrial vegetation and water balance ndash hydrological evalua-tion of a dynamic global vegetation model J Hydrol 286 249ndash270 doi101016jjhydrol200309029 2004
Gerten D Rost S Von Bloh W and Lucht W Causes of changein 20th century global river discharge Geophys Res Lett 35L20405 doi1010292008gl035258 2008
Gerten D Schaphoff S Rastgooy J Deryng D Wallace CWarren R and Edwards N Quantification of Crop and Wa-ter Impacts under Scenarios from D51 ERMITAGE project re-port Open University Milton Keynes UK available athttpermitagecsmanacuksitesdefaultfilesD52pdf 2012
Gordon W S Famiglietti J S Fowler N L Kittel T G F andHibbard K A Validation of simulated runoff from six terrestrialecosystem models results from VEMAP Ecol Appl 14 527ndash545 doi10189002-5287 2004
Guimberteau M Drapeau G Ronchail J Sultan B Polcher JMartinez J-M Prigent C Guyot J-L Cochonneau G Es-pinoza J C Filizola N Fraizy P Lavado W De OliveiraE Pombosa R Noriega L and Vauchel P Discharge sim-ulation in the sub-basins of the Amazon using ORCHIDEEforced by new datasets Hydrol Earth Syst Sci 16 911ndash935doi105194hess-16-911-2012 2012
Hamilton S K Sippel S J and Melack J M Com-parison of inundation patterns among major South Amer-ican floodplains J Geophys Res-Atmos 107 51ndash514doi1010292000JD000306 2002
Hess L L Melack J M Novo E Barbosa C C F and GastilM Dual-season mapping of wetland inundation and vegetationfor the central Amazon basin Remote Sens Environ 87 404ndash428 2003
IPCC Summary for policy makers in Climate change 2007 Thephysical science basis Contribution of working group I to thefourth assessment report of the Intergovernmental Panel on Cli-mate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and MillerH L Cambrigde University Press Cambrigde UK and NewYork NY USA available athttpwwwipccchpublicationsanddataar4wg1encontentshtml 2007
Jachner S Van den Boogaart K G and Petzoldt T Statisticalmethods for the qualitative assessment of dynamic models withtime delay (R package qualV) J Stat Softw 22 1ndash30 2007
Junk W J The Amazon floodplain ndash A sink or source for organiccarbon Mitteilungen des Geologisch-Palaontologischen Insti-tuts der Universitat Hamburg 58 267ndash283 1985
Junk W J and Piedade M T F Plant life in the floodplain withspecial reference to herbaceous plants in The Central AmazonFloodplain edited by Junk W J 147ndash185 Springer BerlinGermany 1997
Jupp T E Cox P M Rammig A Thonicke K Lucht Wand Cramer W Development of probability density functionsfor future South American rainfall New Phytol 187 682ndash693doi101111j1469-8137201003368x 2010
Keddy P A Fraser L H Solomeshch A I Junk W J Camp-bell D R Arroyo M T K and Alho C J R Wet and won-derful The worldrsquos largest wetlands are conservation prioritiesBioscience 59 39ndash51 doi101525bio20095918 2009
Killeen T J and Solorzano L A Conservation strategies to mit-igate impacts from climate change in Amazonia Philos T RSoc B 363 1881ndash1888 doi101098rstb20070018 2008
Langerwisch F Rost S Poulter B Zimmermann-Timm H andCramer W Assessing carbon dynamics in Amazonia with thedynamic global vegetation model LPJmL ndash discharge evaluationVerh Internat Verein Limnol 30 455ndash458 2008
Lehner B and Doll P Development and validation of a globaldatabase of lakes reservoirs and wetlands J Hydrol 296 1ndash22doi101016jjhydrol200403028 2004
Lenton T M Held H Kriegler E Hall J W Lucht WRahmstorf S and Schellnhuber H J Tipping elements in theEarthrsquos climate system Proc Natl Acad Sci 105 1786ndash1793doi101073pnas0705414105 2008
Li W H Fu R and Dickinson R E Rainfall and its seasonalityover the Amazon in the 21st century as assessed by the coupledmodels for the IPCC AR4 J Geophys Res-Atmos 111 1ndash14doi1010292005JD006355 2006
Liang X and Xie Z A new surface runoff parameterizationwith subgrid-scale soil heterogeneity for land surface mod-els Adv Water Resour 24 1173ndash1193 doi101016S0309-1708(01)00032-X 2001
Liang X Lettenmaier D P Wood E F and Burges S J Asimple hydrologically based model of land surface water and en-ergy fluxes for general circulation models J Geophys Res 9914415ndash14428 doi10102994JD00483 1994
Malhi Y and Wright J Spatial patterns and recent trends in theclimate of tropical rainforest regions Philos T R Soc B 359311ndash329 doi101098rstb20031433 2004
Malhi Y Roberts J T Betts R A Killeen T J Li W andNobre C A Climate change deforestation and the fate of theAmazon Science 319 169ndash172 2008
Marengo J A Nobre C A Tomasella J Cardoso M F andOyama M D Hydro-climatic and ecological behaviour of thedrought of Amazonia in 2005 Philos T R Soc B 363 1773ndash1778 doi101098rstb20070015 2008
Marengo J Nobre C A Betts R A Cox P M Sampaio Gand Salazar L Global warming and climate change in Ama-zonia Climate-vegetation feedback and impacts on water re-sources in Amazonia and Global Change edited by Keller MBustamante M Gash J and Silva Dias P 273ndash292 American
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin 2261
Geophysical Union Washington 2009Marengo J A Tomasella J Alves L M and Soares W
R The drought of 2010 in the context of historical droughtsin the Amazon region Geophys Res Lett 38 L12703doi1010292011GL047436 2011
Mayer D G and Butler D G Statistical validation Ecol Modell68 21ndash32 doi1010160304-3800(93)90105-2 1993
Meehl G A Stocker T F Collins W D Friedlingstein P GayeA T Gregory J M Kitoh A Knutti R Murphy J M NodaA Raper S C B Watterson I G Weaver A J and ZhaoZ-C Global climate projections in Climate Change 2007 ThePhysical Science Basis Contribution of Working Group I to theFourth Assessment Report of the Intergovernmental Panel onClimate Change edited by Solomon S Qin D Manning MChen Z Marquis M Averyt K B Tignor M and Miller HL Cambridge University Press Cambrigde UK and New YorkNY USA 2007
Melack J M Hess L L Gastil M Forsberg B R HamiltonS K Lima I B T and Novo E M L Regionalization ofmethane emissions in the Amazon Basin with microwave remotesensing Global Change Biol 10 530ndash544 doi101111j1529-8817200300763x 2004
Mitchell T D and Jones P D An improved method of con-structing a database of monthly climate observations and as-sociated high-resolution grids Int J Climatol 25 693ndash712doi101002joc1181 2005
Moreira-Turcq P Seyler P Guyot J L and Etcheber H Expor-tation of organic carbon from the Amazon River and its main trib-utaries Hydrol Process 17 1329ndash1344 doi101002hyp12872003
Naiman R J Decamps H and McClain M E Riparia Ecol-ogy conservation and management of streamside communitiesElsevier Academic Press ISBN-13978-0126633153 2005
Nakicenovic N Davidson O Davis G Grubler A KramT Lebre La Rovere E Metz B Morita T Pepper WPitcher H Sankovski A Shukla P Swart R Watson R andDadi Z IPCC Special report on emission scenarios availableat httpwwwipccchipccreportssresemissionindexphpidp=0 2000
Nash J E and Sutcliffe J V River flow forecasting through con-ceptual models part I ndash A discussion of principles J Hydrol 10282ndash290 doi1010160022-1694(70)90255-6 1970
Nepstad D C Tohver I M Ray D Moutinho P and CardinotG Mortality of large trees and lianas following experimen-tal drought in an Amazon forest Ecology 88 2259ndash2269doi10189006-10461 2007
Nobre C A and De Simone Borma L ldquoTipping pointsrdquo for theAmazon forest Current Opinion in Environmental Sustainability1 28ndash36 doi101016jcosust200907003 2009
Osterle H Gerstengarbe F W and Werner P C Ho-mogenisierung und Aktualisierung des Klimadatensatzes desClimate Research Unit der Universitaet of East Anglia Norwich6 Deutsche Klimatagung 2003 Potsdam Germany Terra Nostra2003 326ndash329 2003
Parker A J The Topographic Relative Moisture Index An ap-proach to soil-moisture assessment in mountain terrain PhysGeogr 3 160ndash168 1982
Parolin P De Simone O Haase K Waldhoff D RottenbergerS Kuhn U Kesselmeier J Kleiss B Schmidt W Piedade
M T F and Junk W J Central Amazonian floodplain forestsTree adaptations in a pulsing system Bot Rev 70 357ndash3802004
Patt H Hochwasser-Handbuch Auswirkungen und SchutzSpringer Verlag Berlin 2001
Rammig A Jupp T Thonicke K Tietjen B Heinke J Os-tberg S Lucht W Cramer W and Cox P Estimating therisk of Amazonian forest dieback New Phytolog 187 694ndash706doi101111j1469-8137201003318x 2010
Randall D A Wood R A Bony S Colman R Fichefet TFyfe J Kattsov V Pitman A Shukla J Srinivasan J Stouf-fer R J Sumi A and Taylor K E Climate models and theirevaluation in Climate Change 2007 The Physical Science Ba-sis Contribution of Working Group I to the Fourth AssessmentReport of the Intergovernmental Panel on Climate Change editedby Solomon S Qin D Manning M Chen Z Marquis MAveryt K B Tignor M and Miller H L Cambridge Univer-sity Press 2007
Richey J E Mertes L A K Dunne T Victoria R L ForsbergB R Tancredi A C N S and Oliveira E Sources and routingof the Amazon River flood wave Global Biogeochem Cy 3191ndash204 1989
Richey J E Melack J M Aufdenkampe A K Ballester V Mand Hess L L Outgassing from Amazonian rivers and wetlandsas a large tropical source of atmospheric CO2 Nature 416 617ndash620 doi101038416617a 2002
Rost S Gerten D Bondeau A Lucht W Rohwer J andSchaphoff S Agricultural green and blue water consumptionand its influence on the global water system Water Resour Res44 W09405 doi1010292007wr006331 2008
Rowell D P Sources of uncertainty in future changes in local pre-cipitation Clim Dynam 39 1929ndash1950 doi101007s00382-011-1210-2 2011
Seneviratne S I Nicholls N Easterling D Goodess C MKanae S Kossin J Luo Y Marengo J McInnes K RahimiM Reichstein M Sorteberg A Vera C and Zhang XChanges in climate extremes and their impacts on the naturalphysical environment in Managing the Risks of Extreme Eventsand Disasters to Advance Climate Change Adaptation A Spe-cial Report of Working Groups I and II of the IntergovernmentalPanel on Climate Change edited by Field C B Barros VStocker T F Qin D Dokken D J Ebi K L MastrandreaM D Mach K J Plattner G-K Allen S K Tignor Mand Midgley P M 109ndash230 Cambrigde University Press Cam-brigde UK and New York NY USA 2012
Sitch S Smith B Prentice I C Arneth A Bondeau ACramer W Kaplan J O Levis S Lucht W Sykes M TThonicke K and Venevsky S Evaluation of ecosystem dy-namics plant geography and terrestrial carbon cycling in the LPJdynamic global vegetation model Global Change Biol 9 161ndash185 doi101046j1365-2486200300569x 2003
Sitch S Huntingford C Gedney N Levy P E Lomas MPiao S L Betts R Ciais P Cox P Friedlingstein PJones C D Prentice I C and Woodward F I Evalua-tion of the terrestrial carbon cycle future plant geography andclimate-carbon cycle feedbacks using five Dynamic Global Veg-etation Models (DGVMs) Global Change Biol 14 2015ndash2039doi101111j1365-2486200801626x 2008
wwwhydrol-earth-syst-scinet1722472013 Hydrol Earth Syst Sci 17 2247ndash2262 2013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013
2262 F Langerwisch et al Potential effects of climate change on inundation patterns in the Amazon Basin
ter Steege H Pitman N Sabatier D Castellanos H Van derHout P Daly D C Silveira M Phillips O Vasquez RVan Andel T Duivenvoorden J De Oliveira A A Ek RLilwah R Thomas R Van Essen J Baider C Maas PMori S Terborgh J Nunez Vargas P Mogollon H andMorawetz W A spatial model of tree alpha-diversity and treedensity for the Amazon Biodivers Conserv 12 2255ndash2277doi101023A1024593414624 2003
Vigerstol K L and Aukema J E A comparison of tools for mod-eling freshwater ecosystem services J Environ Manage 922403ndash2409 doi101016jjenvman201106040 2011
Wagner W Scipal K Pathe C Gerten D Lucht W andRudolf B Evaluation of the agreement between the first globalremotely sensed soil moisture data with model and precipitationdata J Geophys Res 108 4611 doi1010292003JD0036632003
Willmott C J Some comments on the evaluation of model perfor-mance B Am Meteorol Soc 63 1309ndash1313 1982
Wilson M Bates P Alsdorf D Forsberg B Horritt MMelack J Frappart F and Famiglietti J Modeling large-scaleinundation of Amazonian seasonally flooded wetlands GeophysRes Lett 34 L15404 doi1010292007GL030156 2007
Worbes M The forest ecosystem of the floodplains in TheCentral Amazon Floodplain edited by Junk W J 223ndash265Springer Berlin Germany 1997
WWF HydroSHEDS HydroSHEDS available athttphydroshedscrusgsgov(last access 15 October 2007)2007
Hydrol Earth Syst Sci 17 2247ndash2262 2013 wwwhydrol-earth-syst-scinet1722472013