The well-known Polar Vortex, frigid air originating in the Arctic, was pushed southward in the 2013 – 2014 winter by a high-pressure system in the Pacific, contributing to a cold, snowy and icy winter in North America.
This animation shows the snow cover over North America during the 2013-2014
winter as well as the ice concentration over the Great Lakes. The date and
a graph showing the percent of ice cover over the Great Lakes and Lake
Superior is shown on this version.
Read more at: NASA's Scientific Visualization Studio.