The seasonal maximum extent of Arctic sea ice has passed, and with the passing of the vernal equinox, the sun has risen at the north pole. While there are plenty of cold days ahead, the long polar night is over.
Sea Ice Today
Analyses
Arctic sea ice extent declined more slowly during August 2021 than most years in the past decade, and as a result, this year’s September minimum extent will likely be among the highest since 2007.
Sea ice loss during the first half of August stalled, though ice in the Beaufort Sea is finally starting to weaken. The Northern Sea Route appears closed off in 2021, despite being open each summer since 2008.
The rate of Arctic sea ice loss was somewhat slow through much of July, lowering prospects for a new record low minimum extent in September.
As of July 13, Arctic sea ice extent was tracking just below the 2012 record and very close to 2020, the years with the lowest and second lowest (tied with 2007) minimum ice extent in the satellite record.
At the end of the first week of July, Arctic sea ice extent was tracking at record low for this time of year. July is the month with most rapid sea ice decline.
A stormy May over the eastern Arctic helped to spread the sea ice pack out and keep temperatures relatively mild for this time of year. As a result, the decline in ice extent was slow.
The spring decline in Arctic sea ice extent continued at varying rates through the month of April, highlighted by a mid-month pause.
Arctic sea ice appears to have reached its maximum extent on March 21, 2021, tying for seventh lowest in the 43-year satellite record.
Sea ice extent for February 2021 tracked well below average, but at month’s end was still higher than levels recorded in several recent years. Extent grew at an average pace.
Arctic sea ice extent for January 2021 tracked below average, with the monthly average finishing sixth lowest in the satellite record.
The Arctic climate was extraordinary in 2020, but the year ended with a less spectacular December.
Entering December, which is the start of winter in the Northern Hemisphere, sea ice extent remains far below average, dominated by the lack of ice on both the Pacific and Atlantic sides of the Arctic Ocean.
A vast area of the Arctic Ocean remains ice free as November begins, far later in the season than is typical. The monthly average ice extent for October is the lowest in the satellite record.
Following the sea ice extent minimum on September 15, 2020, expansion of the ice edge has been most notable in the northern Chukchi and Beaufort Seas. The ice edge along the Laptev Sea continued to retreat farther.
On September 15, Arctic sea ice likely reached its annual minimum extent of 3.74 million square kilometers (1.44 million square miles).
In the first week of September, sea ice extent took a sharp downward turn, exceeding the pace of decline for any previous year during that period, and placing the 2020 sea ice minimum firmly as second lowest—after 2012—in the 42-year continuo
After a period of rapid sea ice loss extending into the last week of August, the rate has slowed with the onset of autumn in the Arctic. A region of low concentration ice persists in the Beaufort Sea.
While the Arctic summer is waning, sea ice extent continues to drop. In early August, ice-free pockets began to develop in the Beaufort and Chukchi Seas and expanded steadily through the first half of the month.
The fast pace of ice loss observed in the beginning of July continued through the third week of July, after which the ice loss rates slowed dramatically.