Brad Johnson explains:
This winter saw large regions of Canada and Greenland about 10°C (about 15-20°F) above the historical average. Temperatures in eastern Canada in the dead of winter were a staggering 21°C (37.8°F) above average. The extreme Arctic warming is wreaking havoc with the polar ecosystems and is linked to the catastrophic snowstorms that pummeled the United States. In a summary of how global climate change is becoming observable to people in their daily lives, NASA scientist James Hansen was forced to redraw his global map with hot pink.
The Dish 