Colleen Nagel
Climate Change in the Great Lakes
Purpose:
- Discuss the possible outcomes of climate change on the Great Lakes and the area
surrounding the Great Lakes including health implications and land use change.
Introduction:
- 60 million people live in the Great Lakes region; more than 40 million people use the
Great Lakes as a drinking water source (Patz et al. 2008).
- Climate of the Great Lakes is already changing, such as there are now shorter winters, the
annual average temperature is warmer, duration of lake ice cover is decreasing and heavy
rainstorms are more common (Kling et al. 2003) .
- Climate change is expected to cause a rise in sea level, increase in temperatures, and
changes in the hydrologic cycle, which can cause more floods and droughts (Patz et al.
2008).
Definitions:
Dead zones- area in the water where oxygen levels are less than 2-3 mg/L(or parts per million),
normal levels are about 8-10 mg/L.
Impervious surfaces- surfaces that do not allow a substance to pass through/ penetrate, such as
clay, roads and parking lots, etc.
Statistical downscaling- use of historical observational data from a global model to a local scale.
Precipitation intensity- total precipitation divided by the number of wet days, expressed in inches
or millimeters per hour.
Background:
- Heavy precipitation events are expected to increase with climate change, and are directly
connected to increases in waterborne diseases (Kling et al. 2003).
- In urban watersheds, more than 60% of the annual loads of all contaminants are
transported during storm events, which are caused by heavy rainfall (Kling et al 2003).
- Scenario-based modeling demonstrated how both land use and climate change influenced
the surrounding ecosystem and species, effecting the watershed, discharge, and habitat of
the river (Wiley 2010).
Research Question:
- Will climate change cause a change in the Great Lakes region?
Data, facts and/or trends:
-
-
The frequency of sewer overflow into Lake Michigan is expected to increase from 50%
to 120% by the end of this century from an increase in precipitation events from the
changes in the hydrologic cycle caused by climate change (Patz et al. 2008).
Impervious surfaces increase the volume and velocity of storm water runoff, which
reduces the amount of water absorbed into groundwater. An increase in land cover
conversion could occur from increasing the amount of development of urban areas (Patz
et al. 2008).
-
Indicator bacteria are influenced by precipitation events up to a week prior to sample
collection, however recently precipitation from 0-3 days before has had the strongest
relationship with the data, which are used to help determine what diseases may be in the
water (Patz et al. 2008).
References:
Kling, George W., Katharine Hayhoe, Lucinda B. Johnson, John J. Magnuson, Stephen Polasky,
Scott K. Robinson, Brian J. Shuter, Michelle M. Wander, Donald J. Wuebbles, and
Donald R. Zak. Confronting Climate Change in the Great Lakes Region: Impacts on Our
Communities and Ecosystems. Cambridge, MA: Union of Concerned Scientists, (2003).
Print.
Patz, Jonathan A., Stephen J. Vavrus, Christopher K. Uejio, and Sandra L. McLellan. "Climate
Change and Waterborne Disease Risk in the Great Lakes Region of the U.S." American
Journal of Preventive Medicine 35.5 (2008): 451-58. Print.
Wiley, M. J., D. W. Hyndman, B. C. Pijanowski, A. D. Kendall, C. Riseng, E. S. Rutherford, S.
T. Cheng, M. L. Carlson, J. A. Tyler, R. J. Stevenson, P. J. Steen, P. L. Richards, P. W.
Seelbach, J. M. Koches, and R. R. Rediske. "A Multi-modeling Approach to Evaluating
Climate and Land Use Change Impacts in a Great Lakes River Basin." Hydrobiologia
657.1 (2010): 243-62.