Take your choice from these:I'm trying to think back to how many times in the last 20 years Lake Superior has frozen over (like this year),........ Seems we got a ton of LES from about Mid Dec thru Mid / Late January, but then it shut down for the most part due to the freeze up second week of Feb.
"During most winters, the lake is 40 to 95 percent covered with ice, although it rarely completely freezes. The last time Lake Superior froze over was in 2014. Overall, the Great Lakes reached a 91 percent ice cover that year, which is the most the lakes have frozen since 1979."
"Last time Superior totally froze over was 1997. In 2003 the lake almost froze over again, except the western areas along the Minnesota shoreline."
"With an end in sight, the winter of 2014 rages on, ushering in frigid arctic air and dumping record-breaking snow and ice on much of the nation. This season, ice coverage on the Great Lakes has exceeded all other measurements since 1979.
'By a long shot, this is the most ice we've had on Lake Superior in 20 years,' Associate Professor at the Large Lakes Observatory in Duluth, Minn., Jay Austin said. "
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"Unlike a pond, the depth of the Great Lakes prevent it from being a completely frozen sheet of ice, but instead the ice atop the lakes can actually move with the wind, according to Austin. Due to the ability of the ice to move around, the thickness of the ice across the lakes vary and therefore researchers do not know how thick the ice is in all portions of the lake. So, this makes it hard for scientists to define what freezing over entirely really means.
"NOAA/GLERL has been monitoring and documenting Great Lakes ice cover since the early 1970's using the ice products developed by the U.S. National Ice Center and the Canadian Ice Service."