Huge Arctic sea ice crack, below-average ice extent for 2013: data center
"The 2013 fracturing is quite extensive"
Brittle Arctic sea ice and less Arctic sea ice formation: that’s what characterizes Arctic sea ice during the coldest period of 2013.
A broad area of sea ice fractured off the coast of Alaska and Canada in February, leaving a crack from Ellesmere Island to Barrow, reports the Colorado-based National Snow and Ice Data Center.
Its satellite images show the fracturing event appears to be related to a storm that passed over the North Pole on Feb. 8, creating strong offshore ice motion.
The large area of fractured ice is located in mainly first-year ice, which is thinner and easier to crack than thick, multi-year ice, the NSIDC said.
Similar cracks were observed in early 2011 and 2008, but “the 2013 fracturing is quite extensive,” its ice update said.
Although Arctic sea ice is nearing its winter maximum and will soon begin its seasonal decline, ice extent also remains below average, the NSIDC said.
That’s in part due to warmer-than-average winter temperatures.
During February, air temperatures at about 2,000 feet above sea level were two to five degrees C higher than average across the Atlantic sector of the Arctic, especially near Iceland and in Baffin Bay.
Temperatures remained lower than average by two to six degrees C north of Greenland and the High Arctic Islands, and in the Beaufort, Chukchi and East Siberian seas, linked to unusual low sea level pressure over Alaska and Canada.
Average Arctic sea ice extent for February 2013 was 14.66 million square kilometres.
This is 980,000 sq. km. below the 1979 to 2000 average for the month, and is the seventh-lowest February Arctic sea ice extent in the satellite record since 1979.
Since 2004, the February average extent has remained below 15 million sq. km. every year except 2008.
Before 2004, February average extent had never been less than 15 million sq. km.