This winter's bitter cold temperatures in the Midwest have covered a stunning 79 percent of the Great Lakes in ice.
That's not a record, but it's well above the long-term average of about 51 percent.
Lake Michigan is about 63 percent frozen. Lake Huron is about 85 percent covered.
Lake Erie, at 93 percent, had the most ice cover as of Saturday.
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The data comes from the Great Lakes Environmental Research Laboratory.
It tracks the ice cover because of its potential impacts on everything from hydropower generation to commercial shipping and fishing.
Studying the ice cover also helps determine climate patterns and water levels.