St. Paul, Minn. — The study predicts that within their lifetimes, Minnesotans will see more frequent storms and heat waves, less ice cover on lakes, and possibly more frequent droughts. All those effects will be driven by increasing temperatures.
The study predicts that by the end of this century, summer temperatures in the state will rise by anywhere from 7 to 16 degrees Farenheit. Winter temperatures will rise by as much as 10 degrees.
That would mean that Minnesota's summer climate 100 years from now would resemble present-day Kansas. Its winter climate would resemble present-day Wisconsin.
"To put this warming in perspective, in this century we could see the same warming as has occurred in the last 10,000 years since the end of the last ice age," says Susanne Moser, a staff scientist working on global climate change issues for the Union of Concerned Scientists.
The vast majority of the world's scientists now believe that over the past 50 years, carbon dioxide released by the burning of coal and other fossil fuels has begun to change the earth's climate.
Moser says this latest study is based on "middle-of-the-range" estimates of future carbon dioxide emissions. She says those estimates were fed into the latest computer models and combined with historical weather data from Minnesota to produce the report's predictions.
"There is a high degree of confidence about the temperature projections. There is somewhat less strong confidence in precipitation changes, but basically what we're saying ... we're not making a prediction like 'tomorrow it's going to rain.' It's a prediction that's more (like) 'this is the envelope of possible futures that we're talking about.' And basically what we agree on is that it could be quite serious," according to Moser.
The study predicts a variety of possible repercussions. For example, biologists worry that wildlife will not be able to adjust to such rapid changes in the state's climate.
"Higher temperatures will threaten populations of cold water fishes such as whitefish and brook trout and lake trout," according to Lucinda Johnson of the University of Minnesota at Duluth and one of the study's authors. "Anglers such as my husband and myself will find that trout fishing on the Root River down here in lower Minnesota, and the Baptism River where we fish on the North Shore of Lake Superior, will not be as productive. And as temperatures rise further, these populations could potentially vanish from Minnesota altogether."
Warmer temperatures could extend the length of Minnesota's growing season. That's a potential boon to Minnesota farmers. But the study predicts that benefit could be outweighed by the drier climate and other changes driven by increasing temperatures.
"Climate models predict that precipitation may increase in the spring, but decrease in the summer," says University of Minnesota economic's professor Stephen Polaski, another of the study's authors. "For farmers, this may mean more water when they don't want it, and less water when they do. Hotter and drier summers could cause lower yields. The 1988 drought reduced corn production by 45 percent."
The report urges Minnesota and other Great Lakes states to take action now to cut carbon dioxide emissions and soften the effects of the predicted changes. It recommends that Minnesota utilities reduce the burning of fossil fuels by using windpower and other renewable energy sources. It urges higher milage standards to cut gasoline use by motorists.
The two-year, $500,000 study was funded largely by foundation grants to the Union of Concerned Scientists. The group was founded in 1969 by students and faculty at the Massachusetts Institute of Technology. It combines scientific research with environmental advocacy.