Great Lakes nearing ice cover record

Got ice?

The Great Lakes certainly do, with ice coverage at its highest percentage in 20 years, according to scientists from the Great Lakes Environmental Research Laboratory in Ann Arbor, Mich.

"Persistent cold temperatures in the Midwest this winter have almost completely frozen over many of the Great Lakes," the lab noted in a release last week. Many cities around the Great Lakes are enduring one of their top-five coldest winters on record, the National Weather Service reports.

As of Sunday, 90.5% of the Great Lakes were ice-covered, which is the third-highest level since records began, according to Anne Clites, a scientist with the laboratory. In second place is 1994, at 90.7%.

The record of almost 95% was set in February 1979. "It certainly seems like we have a chance to set the record," Clites said in an e-mail Monday, noting that it will depend on the weather over the next two weeks.

The Climate Prediction Center forecast shows that continuing colder-than-average temperatures are likely over the entire Great Lakes region for at least the next two weeks.

The last time the ice cover was even close to this level was in 1996, when it was approximately 82%.

The near-record ice cover has been bad news for the lakes' shipping industry, whose vessels can't go anywhere when the ports are frozen solid.

However, the ice cover has had some positive effects, like shutting off "lake-effect" snow,

Lake-effect snowfall is common around the Great Lakes in late fall and winter. It occurs when frigid air flows over the relatively warm lake water, which helps create clouds and then snow. But once the lakes freeze over, the temperature difference between land and water is reduced, so this lake effect shuts off.

The ice cover also has made it sunnier in portions of states near the lakes and limited evaporation, which could help boost lake levels, said Jeff Andresen, an associate professor in Michigan State University's geography department and also the state climatologist.

Also, the ice has allowed people access into previously inaccessible "ice caves" near Lake Superior and provided a safe landing spot for an airplane that experienced an emergency over Lake Huron.

Maximum ice cover on the lower lakes normally occurs between mid-February and the end of February, reports the lab, while the maximum on the upper lakes normally occurs between the end of February and early March.

Though ice cover can vary on the Great Lakes from year to year, scientists have seen an overall decrease in ice since records began in the early 1970s, the lab reports.

Contributing: Eric D. Lawrence, Detroit Free Press


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