Beware of the Straight Line: Or How Do You Spell Parabola?

Gauged by the ice cover extent on the Great Lakes, the global warming "trend" is beginning to look more and more like a parabola.

Great Lakes Ice

Comparison of ice coverage since 1980 for Jan 22nd each year from Environment Canada (essentially the National Weather Service of Canada)

And continuing from the National Weather Service Forecasting Office in Milwaukee, Wisconsin,

The image below (from Environment Canada) shows the current year weekly ice coverage for all of the Great Lakes versus the median value (green line) since 1980.  You'll notice that we are more than double the median value for the week around Jan 22nd, and that the current value is actually about 20% higher than the typical peak of ice coverage that occurs around March 12th each year. 

But always remember and never forget -- only evidence that supports global warming theories is actual evidence.