During the first half of August, Arctic ice extent declined more slowly than during the same period in 2007 and 2008. The slower decline is primarily due to a recent atmospheric circulation pattern, which transported ice toward the Siberian coast and discouraged export of ice out of the Arctic Ocean. Therefore there will be no new record minimum in September 2009, but the minimum summer ice extent in 2009 will still be much lower than the 1979 to 2000 average.

From August 1 to 17, Arctic sea ice extent declined at an average rate of 54,000 square kilometers per day. This decline was slower than the same period in 2008, when it was 91,000 square kilometers per day, and for the same period in 2007, when ice extent declined at a rate of 84,000 square kilometers per day.

A recent atmospheric circulation pattern, which led to a change in ice motion, caused the ice loss rate to slow down significantly in the first two weeks of August. During much of June and July, a strong Beaufort Sea high-pressure pattern promoted winds that helped push ice out of the Siberian coastal seas, and also brought clear skies and warm temperatures that helped induce melt. Toward the end of July, the atmospheric pattern changed. Averaged over the past two weeks, a high-pressure system has been centered over the Barents Sea, with low pressure centered over the Laptev Sea. This pattern led to winds that redirected the motion of the ice cover, pushing the ice edge outward toward the Siberian coast and discouraging ice from exiting the Arctic Ocean through Fram Strait.

For updates regarding the present ice conditions go to

http://www.arctic-roos.org/.

If questions contact Prof. Ola M. Johannessen, Mobile: +47 901 35 336.