Sea Ice Today
Analyses
Arctic sea ice extent appeared to reach its maximum extent for the year on March 7, marking the beginning of the melt season. This year’s maximum tied for the lowest in the satellite record.
Arctic sea ice extent for February 2011 tied with February 2005 as the lowest recorded in the satellite record. Sea ice extent was particularly low in the Labrador Sea and Gulf of St. Lawrence.
Arctic sea ice extent for January 2011 was the lowest in the satellite record for that month. The Arctic oscillation persisted in its strong negative phase for most of the month, keeping ice extent low.
Arctic sea ice extent for December 2010 was the lowest in the satellite record for that month.
Arctic sea ice grew more slowly than average in November, leading to the second-lowest ice extent for the month. At the end of November, Hudson Bay was still nearly ice-free.
After reaching its minimum extent on September 19, Arctic sea ice grew rapidly through the first half of October before slowing down late in the month.
Arctic sea ice generally reaches its annual minimum extent in mid-September. This August, ice extent was the second lowest in the satellite record, after 2007.
The end of summer is approaching in the Arctic; temperatures are dropping and melt is ending in the high latitudes. Yet summer is not quite over in the lower latitudes of the Arctic Ocean, where sea ice extent continues to decline.
Arctic sea ice extent averaged for July was the second lowest in the satellite record, after 2007. After a slowdown in the rate of ice loss, the old, thick ice that moved into the southern Beaufort Sea last winter is beginning to melt out.
The rate of ice loss slowed in the first half of July, primarily because of a change in atmospheric circulation. The dipole anomaly, an atmospheric pattern that dominated the Arctic in June, broke down.
Average June ice extent was the lowest in the satellite data record, from 1979 to 2010. Arctic air temperatures were higher than normal, and Arctic sea ice continued to decline at a fast pace.
In May, Arctic air temperatures remained above average, and sea ice extent declined at a rapid pace.
During April, Arctic sea ice extent declined at a steady pace, remaining just below the 1979 to 2000 average. Ice extent for April 2010 was the largest for that month in the past decade.
Arctic sea ice reached its maximum extent for the year on March 31 at 15.25 million square kilometers (5.89 million square miles). This was the latest date for the maximum Arctic sea ice extent since the start of the satellite record in 1979.
In February, Arctic sea ice extent continued to track below the average, and near the levels observed for February 2007. Ice extent was unusually low in the Atlantic sector of the Arctic, and above normal in the Bering Sea.
Despite cool temperatures over most of the Arctic Ocean in January, Arctic sea ice extent continued to track below normal. By the end of January, ice extent dropped below the extent observed in January 2007.
Arctic sea ice extent at end of December 2009 remained below normal, primarily in the Atlantic sector of the Arctic.