NASA and the National Snow and Ice Data Center (NSIDC) collaborated on newly released research that indicated the sea ice extent minimum in the Arctic is the fourth-lowest total on record.
According to Live Science, NASA and the NSIDC released their report Tuesday and reported a figure some hundreds of thousands of square miles larger than the record low set in 2012. This summer, the Arctic's sea ice extent hit is seasonal minimum on Sept. 11 and it reached 1.7 million square miles.
Sea ice extent is measured at the end of summer and at the end of winter to determine how large it grew and how small it shrank, respectively, and the former is typically measured in March and the latter in September. The current record for the lowest sea ice minimum is 1.32 million square miles.
"This year is the fourth lowest, and yet we haven't seen any major weather event or persistent weather pattern in the Arctic this summer that helped push the extent lower as often happens," Walt Meier, a sea ice scientist with NASA's Goddard Space Flight Center in Greenbelt, Md., said in a press release. "It was a bit warmer in some areas than last year, but it was cooler in other places, too."
Arctic sea ice extent has been on a steady decline since the 1970s, Live Science noted, a trend that has been exaggerated in recent years, as sea levels rise and there is more ocean to quicken the melting of the ice. While some months and some years may see the sea ice extent be more resilient, or melt slower, the months and years of record-setting heat are also becoming more common.
"The ice cover becomes less and less resilient, and it doesn't take as much to melt it as it used to," Meier said. "The sea ice cap, which used to be a solid sheet of ice, now is fragmented into smaller floes that are more exposed to warm ocean waters. In the past, Arctic sea ice was like a fortress. The ocean could only attack it from the sides. Now it's like the invaders have tunneled in from underneath and the ice pack melts from within."
