April 7, 2007 at 1:00 am

Warming saps Great Lakes

Water levels could take big drop as Earth gets hotter

WASHINGTON -- Data from a new United Nations report on climate change make it more likely that an increasingly arid American southwest will seek access to Great Lakes water, Michigan's top climate official said Friday.

The report also strengthens scientific opinion that Michigan will see other dramatic effects in the coming decades: lower Great Lakes water levels, a dramatically receding Lake St. Clair, and summers by the end of the century that feel more like northern Mississippi than to what Michiganians are now accustomed. And the findings are likely to increase political pressure on the embattled U.S. automakers to increase fuel efficiency, something Detroit's automakers have said will cost money and jobs.

The report, released Friday in Belgium by the U.N.'s Intergovernmental Panel on Climate Change, is perhaps the starkest warning yet from scientists about how a global increase in temperatures is likely to affect the Earth. The report, the second of three to be released by the panel this year, found that "much more evidence has accumulated in the last five years" that human activity already is warming the globe, and that continued warming is likely to threaten the survival of as many as 30 percent of the world's animal and plant species.

In the United States, the most dramatic impact is likely to occur in the south and west: Using data from the U.N. report's climate models, a separate paper published in the journal Science projects that the Southwest will become increasingly dry and hot. Conditions will be similar to the Dust Bowl of the 1930s, which occurred when dust storms carried topsoil across hundreds of miles in the Great Plains.

Political fallout on way

"That is going to make a resource like the Great Lakes basin, with its huge supply of fresh water, look very, very tempting," said Jeffrey Andresen, a Michigan State University researcher and Michigan's state climatologist. "Some of the legal aspects of who controls the water in the Great Lakes are being questioned now, but it's likely that will intensify."

Current law makes it nearly impossible for areas outside the region to gain access to Great Lakes water, but U.S. and Canadian officials have long worried that increasing demand for water in the Southwest, even without the effects of climate change, threaten the status quo.

Also likely to intensify are calls in Washington for actions to limit the causes of global warming, including auto emissions. The Bush administration and members of both parties in Congress have made several proposals to force an increase in gas mileage, something the Big 3 have resisted. On Wednesday in New York, GM executive Robert Lutz suggested the Bush proposal could add $6,000 to the price of the company's cars.

"What we're seeing in Washington is pressure for higher fuel standards, and that pressure will not go away," said David Gard of the Michigan Environmental Council. Michigan risks more economic damage if business and political leaders continue to resist that pressure, Gard said.

Reacting to the report, Jim Connaughton, the White House's top environmental official, said Friday that Bush's proposal to increase mileage standards "would be extremely valuable" in addressing the problem. Many Democrats want to go farther: Sen. Barbara Boxer, D-Calif., who chairs the Senate Environment Committee, said Friday the report will strengthen her call for the Environmental Protection Agency to regulate greenhouse gas emissions, something the Bush administration has resisted.

"We take the issue of climate change very seriously," said Mike Moran, Ford Motor Co.'s chief Washington spokesman. Reducing emissions from cars and trucks is part of the solution, but only part, Moran said.

Changes to remake Mich.

Data from the U.N. report and other recent research suggests dramatic effects in Michigan, experts said Friday:

  • Worst-case scenarios suggest Great Lakes water levels could drop four to five feet, said Scudder Mackey of Canada's University of Windsor. Lake St. Clair could lose up to 20 percent of its surface area, with the lakeshore receding as much as 3 1/2 miles in some spots, Mackey said. The shrinkage comes primarily from the lack of ice cover during winter, which allows Great Lakes water to evaporate more quickly. On Lake Superior, for example, researchers from the University of Minnesota-Duluth said surface temperatures have increased about 4.5 percent since 1979.

  • Michigan agriculture could see some short-term gains, Andresen said, as warmer weather lengthens growing seasons. But there is also risk: Michigan's cherry crop, the largest in the nation, could be endangered by patterns such as that showing up this spring, when early warming starts cherry trees on their yearly growth cycle only to be damaged by spring freezes.

  • Warm winters could threaten jobs tied to winter recreation, said George Kling, a University of Michigan ecologist. Within 30 years, Michigan summers are likely to feel more like those in Kentucky today, he said, and by the end of the century, summer weather will resemble Arkansas and northern Mississippi.

  • The habitats of Michigan's animal and plant species will change dramatically, as will the migration patterns of birds, said Terry Root, a Stanford University and former U-M biologist who was an author of the U.N. report. Species once considered "invasive," such as the zebra mussel, will become native, she said.

  • North America will experience more severe storms with human and economic loss, and cultural and social disruptions. It can expect more hurricanes, floods, droughts, heat waves and wildfires, it said.
  • Africa will be hardest hit. By 2020, up to 250 million people are likely to be exposed to water shortages.
    Who attended: Delegates from more than 120 nations, including the U.S., met in Brussels, Belgium.
    What's next: The findings' summary will be presented to the G8 summit of the world's richest nations in June, when the European Union is expected to renew appeals to President Bush to join in international efforts to control emissions of fossil fuels.
    Source: Associated Press