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Arctic sea ice hits new low for June
The Arctic sea ice extent dropped rapidly in June and reached a record low level for that month, the National Snow and Ice Data Center has reported. The June record follows near record low ice cover in May. The June ice extent came in at 498,000 square miles below the average June extent over the years 1979 to 2000, during which satellite observations of the sea ice have been carried out. And the rate of ice decline was the fastest on record for June, NSIDC said.
However, the question of whether the minimum Arctic sea ice extent for 2010 will fall below the record-setting minimum in 2007 will depend on continuing Arctic weather conditions. The minimum extent normally occurs in September and NSIDC expects the ice melt to slow down as the melt moves into thicker, multiyear ice in the central Arctic Ocean.
“Loss of ice has already slowed in the Beaufort and Chukchi seas due to the tongue of thicker, older ice in the region,” NSIDC said.
Climate anomaly In 2007 a climate anomaly in which there was unusually high atmospheric pressure over the northern Beaufort Sea and unusually low pressure over the Kara Sea on the Eurasian coast caused a wind pattern that pushed ice away from the coast, thus accelerating the ice melt and causing more ice than usual to flush from the Arctic Ocean into the North Atlantic.
That same anomaly exists this year. But, with the pressure pattern configured slightly differently from in 2007, it is not yet clear whether the anomaly will drive a new record ice extent minimum, NSIDC said.
However, the narrow Nares Strait between northwest Greenland and Ellesmere Island has been reported clear of an ice plug that normally prevents sea ice from flowing south before early July, NSIDC said. And, although relatively small amounts of ice normally flush south through the Nares Strait, the ice involved is some of the thickest in the Arctic — the loss of thick, multiyear ice is of particular concern in the overall loss of sea ice.
—Alan Bailey
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