The National Snow and Ice Data Center has released satellite data showing that with the extent of ice in the Arctic Ocean is nearing its yearly minimum, the area of the Arctic Ocean covered by ice is at its third lowest in the historical record:
The extent of ice in the Arctic Ocean is four standard deviations below the average extent of ice from 1979-2000, indicating that it is very, very unlikely — actually, 99.994% unlikely — for there to be this little ice merely by chance. Something has changed in the Arctic.
That change in the Arctic appears to be accelerating. The linear trend for the decrease in the extent of ice measured each August from 1979-2007 was 0.84% per year. When data from August 2008 was added, the linear trend for the rate of decrease in ice increased to 0.87% per year. With data from August 2009 and August 2010 added in, the linear trend for the rate of decrease in ice increased again to 0.89% per year.