Climate Change in the Great Lakes By: Colleen Nagel

Outline Human Geography and Economy Climate Trends and Variability in the Great Lakes Region Historical Records of Change: Lake Temperature, Ice Cover, and Water Levels Projections of Future Climate in the Great Lakes Region Climate Change and Waterborne Disease Conclusion

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).

Human Geography and Economy 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). In 2000 over 50% of manufacturing shipments in Canada came from Ontario (Wiley et al. 2003). The 6 Great Lakes states make up >25% of total value to U.S. manufacturing (Wiley et al. 2003).

Climate Trends and Variability in the Great Lakes Region In 1999 over a 4-year time span annual average temperatures 2-4 ̊F warmer and 7 ̊F above average winter Increase in precipitation in last 3 decades s_&_Inland_Sites.htm

Historical Records of Change: Lake Temperature, Ice Cover, and Water Levels Lake Temperature: Lengthened summer stratification Duration of lake ice: Freeze-up occurring later in fall and ice-out earlier in the spring for the past century Fall freeze 1.5 days later per decade Spring breakup earlier by 2 days per decade El Niño/La Niña

Climate Change and Waterborne Disease Risk in the Great Lakes Region of the U.S. By: Jonathan A. Patz, Stephen J. Vavrus, Christopher K. Uejio, and Sandra L. McLellan 60 million people live in the Great Lakes region; more than 40 million people use the Great Lakes as a drinking water source 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

Global Climate Models (Patz et al. 2008)

Heavy Daily Precipitation Heavy daily precipitation 1-5 cm Time frame of late 20 th century to late 21 st century Model was made from historical relationship from Global Climate Models and daily precipitation levels from a local scale (Patz et al. 2008)

Case Study Milwaukee River Basin: 1,440km² of rural, agricultural, suburban, and urban land use. Basin’s watersheds drain into 3 major rivers and discharge into Lake Michigan E. coli is used as an indicator bacteria Storm events >3in of rainfall within 24 hrs. may overwhelm the combined sewer systems and lead to overflow

Levels of E. coli in Milwaukee Estuary (Patz et al. 2008)

Lake Geneva, Wisconsin (Patz et al. 2008)

Surveillance of Indicator Bacteria Wind direction toward or away from the beach influences indicator bacteria Tidal cycles from subsurface and soil reservoirs Precipitation and runoff events

Conclusion of paper Data collection/surveillance Infrastructure improvements Land use planning Education and research

Projections of Future Climate in the Great Lakes Region By temperatures will increase by 3- 4 ̊F in spring and summer 10-20% increase in precipitation by the end of the century Migrating climates

Conclusions Increase in temperatures Decrease in the duration of ice cover Migrating climate Increase in precipitation Changes in hydrologic cycle

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): 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 (2010):