As the polar vortex finally begins to loosen its grip on America, it's leaving some very unusual sights in its wake.
We've already seen how sections of the Niagara Falls have turned to ice, and now Lake Michigan has been taken over by boulder size balls of ice which have broken off the massive ice sheets that cover the lake during the winter.
A YouTube user uploaded video footage of the ice balls bobbing in the water in Glen Arbor, Michigan yesterday.
According to park ranger Anne Lipsomb, the balls can weigh up to 75 pounds. She told MLive that the chunks of ice gain their rounded shape as they are tossed about by the waves and, depending on the temperature, they may keep growing bigger as layers of water coat the ball and then freeze. According to the Daily Mail, they don't sink because solid ice is less dense than liquid water.
A similar sight occurred last winter in Lake Michigan's Good Harbour Bay, but those balls weren't quite as large as the ones that have been sighted this year.
Last year, Tom Ulrich, the deputy superintendent from the Sleeping Bear Dunes National Lakeshore told UpNorthLive: "It's not that it never happens and this is a once in a decade thing. It happens more often than that, but these are very large and got bigger than they normally get."
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