Jay Austin, a Duluth professor and a researcher with the University of Minnesota-Duluth’s Large Lakes Observatory, is surprised to find the waters of Lake Superior to be warming at a such rapid pace. For a man who made a career studying decades of data on the Great Lakes, he knows it’s no mystery that there is a warming climate around Lake Superior but is surprised to see the water of the lake itself warming even more rapidly.

Through his research, Jay Austin found the water temperature rising almost twice as fast as the air temperature. His studies concluded that water temperature was rising more than 4 degrees for the average surface temperature.

The Great Lakes

This rapid increase in water temperature is having dramatic effects. “The date of what we call the spring overturn has been getting earlier in the year,” Austin said. “It’s basically the start of the summer season in the lake. It’s when you start to develop strong positive stratification: warm water sitting on top of cool water.”

In these last two decades, the spring turnover have been constantly arriving earlier. Recently the spring turnover has moved up two weeks from early July to mid-June. The reasoning behind this is due to a loss of ice cover. Since ice is reflective, when it’s not there it makes it easier for the lake to absorb heat.

Ice Cover over Lake Superior

According to Austin, in another 35 to 40 years Lake Superior will only have minimal ice covering the top of the lake. This news isn’t good for plants and animals including the lake’s native whitefish. “If there’s less ice over time, and there appears to be, there’s a chance for greater storminess in the sort of shallow water (bays) that the whitefish spawn in,” said Steve Coleman, who directs the Large Lakes Observatory.

Another potential problem is that warming speeds up the growth of fish and the plants they feed on. If warming continues to increase, it can create big problems. The lake will have a reduction in the flow of nutrients into the system across that temperature gradient. The Duluth scientists’ next project is trying to prove their suspicion that diminishing ice is contributing to falling lake levels. Hopefully, there will be resolution soon found to keep the water temperatures in Lake Superior from rising. There needs to be a resolution found in order to keep the environment living and the plants and living organisms from dying.

Sources:

http://www.epa.gov/glnpo/

http://www.enn.com/today.html?id=12293

Photo Source:

http://upload.wikimedia.org/wikipedia/commons/8/8e/Great_Lakes_1.PNG

http://upload.wikimedia.org/wikipedia/en/3/3e/LakeSuperior_arf.JPG