Climate-Induced Hydrologic and Geochemical Modifications in Alluvial and Coastal Watersheds

Ming-Kuo LeeJames Saunders

Ashraf UddinChandana Mitra

Li DongYingru Li

Luke Marzen

Department of Geology and Geography, Auburn University

Global Climate Change

Warmer atmosphere

Reduce Ice Volume

Sea levelrise

Rivers dry up

Water shortage fordrinking & irrigation

Higher water temperature

Extreme Climate Events

Intensive precipitationExtreme droughtsStrong evaporation

Water salinity Dissol oxygen

flooding

Runoff

Humanpollutantsreleases

Coastal erosion, flooding, saltwater intrusion

Climate change is changingwater availability & quality!!

Water quality Water availability

Sea level and ocean temperature change since Pliocene (3 Ma)

a. Pleistocene glaciation

b. Holocene warm upSosdian and Rosenthal (2009, Science)

Natural Groundwater Arsenic Contamination in Holocene Alluvial Aquifers(WHO: the worst environmental health crisis of modern time)

Is Climate Change to Blame?

Bangladesh Wells:

Drinking water “tube” wells

(10-75 m of depth):

10 million

27% with As > 50 µg/L (BGS data)

arsenic-affected population:

10 µg/L: 57 million

50 µg/L: 35 million

arsenical dermatitis: 1 million

cancer deaths: > 200,000

(Shamsudduha et al., 2008)(NSF funded research, 06-08, 11-12, 14-17)

(Lee et al., 2013)

Arsenic (ug/kg)D

epth

(m)

0 200 400 600 800 10000

100

200

300

400

Holocene

Pliocene-Pleistocene(120ka-12ka)

Sea

Lev

el R

ise

Fast flushing

Slow flushing

As (mg/L)

Eh

(mV

)

0 0.5 1 1.5-200

-100

0

100

200

300

Arsenic is mobilized under sluggishand reducing geochemical conditions

Fast hydrologic flushingoxidized

Fe-reducing

2MnO2 + 4FeO(OH)*As + 2CH2O + 10H+ 2Mn2+ + 4Fe2+ + 2HCO3

- + 8H2O + As(III)

The monthly global mean sea level (1880 to 2009)

Church and White (2011)

Average rate from 1880 to 2009: 1.94 mm/year1880 1900 1920 1940 1960 1980 2000 2020

-200

-150

-100

-50

0

50

100

Time

Glo

bal m

onth

ly m

ean

sea

leve

l (m

m) Rate from 1993 to 2009:

3.44 mm/year

Slow arsenic flushing in alluvial aquifers will likely continue if this acceleration of sea-level rise remains its current course

Will sea level rise and saltwater intrusion mobilize more arsenic?

NASA Innovations in Climate Education (NICE) $600k funding to develop and implement new education modules into the existing course of study for 6-12 grade science classroom (Dr. Wooten’s legacy)

Generate a better informed public that understand the consequences of climate change

learning activities include field data collection, computer simulations, and laboratory measurement. Teachers are trained in the use of these modulesthrough partnership with Alabama Science in Motion

Host Global Climate Change in Education Symposium in 2012

Education modules were published in Springer’s Handbook of Climate Change Mitigation (2012, 2014)