Click image for an excellent, comprehensive article by Chris Mooney at the Washington Post. Image courtesy of the National Snow and Ice Data Center.
Most reports of
Arctic ice cover concern the minimum recorded at the end of each summer. But there's another important measurement that occurs around this time of year: the maximum reached at the end of the winter. And 2015 is shaping up for a
record "low" maximum:
Sea ice in the Arctic is near its all-time minimum for the end of winter and could break the previous record within the next two weeks if it fails to grow, according to the latest satellite data. The area of the Arctic covered by floating sea ice is already the lowest for this time of year, highlighting the long-term warming trend experienced by the region in both winter and summer months. ...
Sea ice in summer has shrunk by 30 per cent on average over the past 30 years while average temperatures in the Arctic have risen by about 4C – more than 3C warmer than the global average.
The ice cover has been known to grow significantly throughout March, so it's not a done deal yet. But we're far enough along that the smart money is betting on a new winter low.
Starting from a new winter low would obviously increase the odds of a new summer low. But another effect would be continued icy winters along the eastern seaboard. Climate researchers have found that as the Arctic warms and the gradient between chilly northern air and warmer air at mid-latitude decreases, the jet stream weakens, becomes chaotic, and from time to time dips much further south than usual, bringing cold dry air into contact with moist Atlantic air. That's what happened in 2015, causing nearly nonstop blizzards to bury the eastern portion of the US for days on end.