Update: NSIDC pinpoints Sept. 19 as date of least Arctic ice extent in 2010
Arctic Sea Ice Extent, which the National Snow and Ice Data Center (NSIDC) in Boulder, Co., announced had reached its annual minimum on Sept. 10, has now slipped even further, to a point that could be below the 2008 minimum. That would make this the second lowest summer ice cover in recorded history.
“It’s awfully close (to the 2008 low),” NSIDC research scientist Dr. Walt Meier said on Wednesday (Sept. 22, 2010). “And even though the air temperatures are getting colder, the ocean has a lot of heat in it and can continue to melt ice.”
Meier acknowledged that the NSIDC jumped the gun in announcing the apparent annual minimum. The ice extent had been increasing for three consecutive days and the scientists assumed the season had turned. But much of the ice is broken up and thin, conditions that mean “it doesn’t take a lot to get late season melting,” Meier said.
Ice watchers may be more concerned, however, by the inset Polar Science Center graph of ice volume, which shows that the total amount of ice (as differentiated from the extent of the Arctic ice cover) has dropped off a cliff.