NASA satellites, WMS reveal arctic grip
For people in North America and Eurasia it’s not news the last month was one of the coldest in decades. The NASA satellite data WMS in Gaia above illustrates just how much colder it's been compared to average temperatures recorded in December between 2000 and 2008. Places that are warmer than average are red, places that were near-normal are white, and places that were cooler than average are blue. According to climate gurus this pattern is a sign of "negative" Arctic Oscillation - where cold Arctic air chilled the land surface at midlatitudes, while Arctic land (Greenland and Alaska), was warmer than usual. Over most of the past century, the Arctic Oscillation alternated between positive and negative phases. Starting in the 1970s, however, the oscillation tended to stay in the positive phase, causing lower than normal arctic air pressure and higher than normal temperatures in much of the US and northern Eurasia. Not quite the Day After Tomorrow - but damn cold nonetheless.