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Arctic sea ice cover second lowest on record

Doug O'Harra
Arctic sea ice, as captured by the AMSR-E instrument on NASA's Aqua satellite on Mar. 7, 2011, when the maximum extent of sea ice this year was recorded.
Image courtesy of NASA's Scientific Visualization Studio, Goddard Space Flight Center
Arctic sea ice is near its smallest extent of 2011, near the end of summer and the end of the Arctic ice melt season. This data visualization shows Arctic sea ice as recorded on Sept. 9, 2011 by the AMSR-E instrument on NASA's Aqua satellite.
Image courtesy of NASA's Scientific Visualization Studio, Goddard Space Flight Center
On July 20, the U.S. Coast Guard Cutter Healy steamed south in the Arctic Ocean toward the edge of the sea ice.
Photo by Kathryn Hansen/NASA
On July 12, 2011, crew from the U.S. Coast Guard Cutter Healy retrieved a canister dropped by parachute from a C-130, which brought supplies for some mid-mission fixes.
Photo by Kathryn Hansen/NASA
These Arctic sea ice images represent real data captured by NASA’s Aqua satellite. The top image is from Mar. 7, when sea ice reached its maximum extent this year and the bottom image is from Sept. 9, around the time sea ice reached its minimum extent this year.
Image courtesy of NASA's Scientific Visualization Studio, Goddard Space Flight Center

UPDATED 9/16/11: Arctic sea ice has continued to grow during the past few days, prompting the National Snow & Ice Data Center to call the toss in favor of winter freeze-up. “Arctic sea ice appears to have reached its lowest extent for the year,” says the latest dispatch. “The minimum ice extent was the second lowest in the satellite record, after 2007, and continues the decadal trend of rapidly decreasing summer sea ice.”

Don’t relax just yet. The NSIDC satellite jockeys have added this caveat: “Changing winds could still push ice flows together, reducing ice extent further.” The final analysis of the 2011 melt season is yet to come.

(Original story) With the extent of frozen sea across the Arctic Ocean hovering at the second lowest level seen during the 32 seasons of satellite monitoring, melting has slowed way down and probably won’t set a new minimum record in 2011, according to the National Snow and Ice Data Center.

“The rate of decline has flattened considerably the last few days: Arctic sea ice is likely near its minimum value for the year,” the NSIDC said in this report posted Tuesday. “However, weather patterns could still push the ice extent lower.”

As of Sept. 10, polar ice covered about 1.68 million square miles — about 42,500 square miles above the record minimum seen on the same date in 2007. This chart tracking the decline shows a tiny uptick in extent had  occurred.

Other satellite data interpreted using different calculations say the area covered by sea ice in 2011 actually did shrink below the 2007 record, the NSIDC noted. In any case, the agency will make an announcement and post more analysis when the ice has stopped shrinking for several days in a row and appears to be growing in response to the colder temperatures of approaching winter.