This summer we have had confirmation that Arctic ice behaviour has everything to do with wind. During June, winds were circulating clockwise in an inwards spiral, which caused ice extent to diminish and ice concentration to remain high. Around July 1, the patterns reversed and we have seen counterclockwise winds pushing ice away from the pole. As a result, ice area/extent has scarcely changed and instead we see a gradual decline in average ice thickness. The video below shows June/July ice movement and thickness. The graph below shows changes in ice thickness during summer over the last five years. Based on past behaviour, we can expect the average ice thickness to flatten sometime in the next two weeks. It should bottom out somewhere between 2006 and 2009. NSIDC has warned me that PIPS is not an accurate measure of ice thickness, though I would have to say it has done remarkably well as a predictor of this summer’s behavior. As you can see below, 2010 is following a track similar to 2006. We are at peak melt season, and there just isn’t much happening in the Arctic. The Arctic Oscillation has turned slightly positive in July, which tends to keep cold air contained in the Arctic and out of lower latitudes. Ice has flatlined in the North, while it goes through the roof in the south. Continued at: http://wattsupwiththat.com/2010/07/11/sea-ice-news-13/ added by: Dagum
