Study projects steep Great Lakes water level drop if greenhouse gases remain unchecked

By Haley Walker
Walkerh4@msu.edu
Great Lakes Echo
Sept. 30, 2009

Great Lakes water levels could drop by up to two feet by the turn of the century as temperatures rise, according to a recent series of reports released by the Union of Concerned Scientists.

The water decline is a response to global climate change, according to the report by the group of scientists and citizens that advocates for science-based solutions to environmental problems. Warming temperatures reduce ice cover and increase evaporation. Lake Huron and Lake Michigan are projected to have the greatest changes.

“Less winter ice and warmer temperatures in the summer could mean a decrease of one to two feet in Great Lake levels by the end of the century,” said Melanie Fitzpatrick a climate scientist with the organization.

The series of reports, Confronting Climate Change in the U.S. Midwest, aims to explain the current effects and predict potential consequences of climate change on Midwest states. The reports cover Illinois, Iowa, Michigan, Wisconsin, Indiana, Minnesota, Missouri and Ohio.

Other projections of the report for the end of the century if climate change is unchecked:

•    Each summer, Chicago would face 70 days with temperatures greater than 90 degrees, and at least two major heat waves.
•    Spring and winter in Michigan would see a 25 percent increase in precipitation.
•    All summers in Wisconsin would be hotter than in 1988, the state’s hottest summer on record.
•    Indiana, as well as several other states would experience warmer winters. That extends the growing season by six weeks. It also allows pests more time to destroy crops.
•    Snow days in Minnesota would decrease by a third.
•    Cincinnati would face more than 85 days with temperatures greater than 90 degrees. Cleveland could see more than 60 days that are that warm.

The carbon emissions that contribute to global warming in the Midwest are higher than the entire west or east coasts. according to the World Resources Institute, a center for policy research on global environmental and resource issues. The region is the seventh largest contributor worldwide.

Fitzpatrick cited manufacturing, power production and transportation possible reasons for the high levels in the region.

“Most of the electricity in many of these states comes from coal fired emissions,” she said.

The 2009 reports are different from the organization’s reports released in 2003, Fitzpatrick said.

“These state reports go down to a very small scale,” she said. “The last reports were looking at effects on the Midwest as a whole, and these are much more telling of what may happen to an individual region.

They also include forecasts for what would happen if causes of climate change was addressed.

“In the first report, we used a single possible future,” Fitzpatrick said. “Here, we are comparing two possible futures, to show we have a choice and to show what we can do to avoid the changes.”

Changes to agricultural production, seasonal temperature levels, precipitation and deterioration in air quality are effects of climate change shared by all the states included in the study.

“This is really a place that we need to be looking at the emissions,” Fitzpatrick said. “These reports are a very strong message of what is happening.”