final presentation to manitoba hydro
TRANSCRIPT
The frequency, severity and causes of extreme droughts in the
Winnipeg River basin
Scott St. GeorgeGeological Survey of Canada
2003
geosciences
1. California Institute of Technology
2. Massachusetts Institute of Technology
3. Stanford University
4. University of California - Berkeley
5. Columbia University
6. University of Michigan
7. Pennsylvania State University
8. University of Arizona
9. Harvard University
10. University of Texas - Austin
EARTH SCIENCES RANKINGS
US News and World Report, 2006
2008
The frequency, severity and causes of extreme droughts in the
Winnipeg River basin
Scott St. GeorgeGeological Survey of Canada
FUNDING AGENCIES
Manitoba Hydro
Manitoba Geological Survey
Natural Resources Canada
National Science and Engineering Council of Canada
Prairie Adaptation Research Collaborative
WINNIPEG RIVER STREAMFLOW
relative change in summer flow
Schindler and Donahue, 2006, PNAS
South Saskatchewan River at Saskatoon
LOW
HIGH LOW
HIGH
St. George, 2007, Journal of Hydrology
trends
Annual discharge since 1924
Annual discharge since 1924
NO TREND
NO TREND
NO TREND
NO TRENDNO TREND
+ 46%
+ 52%
+ 58%
““For monthly and annual average flow based on adjusted disaggregated flow data, upward trends are detected for the entire period from 1912 to 2006.
Liu, 2007
Western Hudson Bay
Saskatchewan River≠Winnipeg River
Canadian Prairies
1892
what happened
before that?
paleoclimatologythe study of the Earth’s climate prior to the period of instrumental measurements
RECORDS FROM ANCIENT TREES
never trust one tree
975trees
286,420tree rings
Photograph courtesy Kurt Kipfmueller
1783
755 m3/s847 m3/s809 m3/s770 m3/s823 m3/s787 m3/s901 m3/s840 m3/s
TREE RINGS AND PRAIRIE DROUGHT
Martin-Philippe Girardin Canadian Forest Service
Greg Pederson United States Geological Survey
Erik Nielsen Manitoba Geological Survey
Emma WatsonEnvironment Canada
Glen MacDonaldUCLA
David Sauchyn University of Regina
Jacques Tardif University of Winnipeg
2,860trees
Prairie tree-ring network
755 m3/s847 m3/s809 m3/s770 m3/s823 m3/s787 m3/s901 m3/s840 m3/s
HYDROLOGY
CLIMATE
direct
HYDROLOGY
CLIMATE
direct
PROXIES
direct
HYDROLOGY
CLIMATE
direct
indirectPROXIES
direct
This must be
voodoo.Anonymous water
manager
“
”
How good are drought records from
tree rings?
geography matters
Prairie tree-ring network
PalmerDroughtSeverityIndex
1900 1920 1940 1960 1980 2000
Year (A.D.)
-10
-5
0
5
10PD
SI
-3
-2
-1
0
1
2
3
Rin
gwid
th
southern Alberta
St. George et al., (accepted), Journal of Climate
1900 1920 1940 1960 1980 2000
Year (A.D.)
-10
-5
0
5
10PD
SI
-3
-2
-1
0
1
2
3
Rin
gwid
th
r = 0.62
St. George et al., (accepted), Journal of Climate
southern Alberta
1900 1920 1940 1960 1980 2000
Year (A.D.)
-6
-4
-2
0
2
4
6
PD
SI
-3
-2
-1
0
1
2
3
Rin
gwid
th
59
northwestern Ontario
St. George et al., (accepted), Journal of Climate
r = 0.40
755 m3/s847 m3/s809 m3/s770 m3/s823 m3/s787 m3/s901 m3/s840 m3/s
How bad has drought been?
‘Then’‘Now’(AD 1900 - present) (AD 1500 - 1900)
1783
How bad has drought been?
1910
1720s
How bad has drought been?
more persistentmore severe
in some watersheds
73
74
PRODUCTS AND APPLICATIONS
data
W O R L DD ATA C E N T E R f o rPA L E O C L I M AT O L O G Y
Publications
Scott St. George
Streamflow in the Winnipeg River basin, Canada: trends, extremes and climate linkages Journal of Hydrology 332, 396-411, 2007
Scott St. George, Dave Meko and Mike Evans
Regional tree growth and inferred summer climate in the Winnipeg River basin, Canada since AD 1783 Quaternary Research 70, 158-172, 2008
Scott St. George, Dave Meko, Martin Girardin, Erik Nielsen, Greg Pederson, Dave Sauchyn, Jac Tardif, and Emma Watson
The tree-ring record of summer drought in the Canadian Prairies Journal of Climate, in press
does the past really matter?
3mainapplications
YOU CAN TOUCHclimate change
BENCHMARKSfor recent events and trends
91
‘paleo’ scenariosstarting points for
VIC BAKER UNIVERSITY OF ARIZONA
“Common sense holds that what has really happened
CAN HAPPEN AGAIN“
VIC BAKER UNIVERSITY OF ARIZONA
FUTURE DIRECTIONS
Prairie tree-ring network
1900 1920 1940 1960 1980 2000
Year (A.D.)
-6
-4
-2
0
2
4
6
PD
SI
-3
-2
-1
0
1
2
3
Rin
gwid
th
95
northwestern Ontario
St. George et al., (accepted), Journal of Climate
r = 0.40
Can we do
better?
ring widthfdrought
ring widthfdrought
ring chemistry
ring widthfdrought
ring chemistry
ring density
HYDROLOGY
CLIMATE
direct
indirectPROXIES
direct
HYDROLOGY
?climate changegeological
The frequency, severity and causes of extreme droughts in the
Winnipeg River basin
Scott St. GeorgeGeological Survey of Canada