The National Snow and Ice Data Center (NSIDC) reported yesterday that the average rate of Arctic ice melt in July was nearly equal to that in the record-breaking year of 2007. Total ice extent for the month was the third lowest for the satellite record in July, following behind 2007 and 2006.
A strong area of high pressure over the western Arctic brought warm temperatures and clear skies to the region, helping to promote the melting process. (The same high pressure ridge brought record breaking high temperatures to much of the western U.S. from Arizona through Oregon and Washington and into Alaska.)
The NSIDC overview stated:
Sea ice extent averaged over the month of July 2009 was 8.81 million square kilometers (3.40 million square miles). This was 680,000 square kilometers (263,000 square miles) above the record low that occurred in July 2007, 250,000 square kilometers (97,000 square miles) below July 2008, and 1.29 million square kilometers (498,000 square miles) below the 1979 to 2000 average. Sea ice extent is unusually low in the Kara Sea, Baffin Bay, and along the Russian coast. The only area with significant above-average ice extent is southern Hudson Bay.Image (click to enlarge): Arctic sea ice extent as of August 4 from NSIDC