Arctic Sea Ice Extent Reaches a Dramatic New Low

As the summer melt season ends, Arctic sea ice extent has now fallen to an exceptionally low level, covering an area only half the size of the 1979 to 2000 average. The

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Arctic Sea Ice Extent September 2012

NSIDC
Arctic sea ice extent, Sept. 16
Colorado-based National Snow and Ice Data Center (NSIDC) reported that as of September 16, Arctic sea ice extent was only 1.32 million square miles, which is 18 percent below the previous record low of 1.61 million square miles, set in September 2007. “We are now in uncharted territory,” said NSIDC director Mark Serreze. “While we’ve long known that as the planet warms up, changes would be seen first and be most pronounced in the Arctic, few of us were prepared for how rapidly the changes would actually occur.” A key reason for the precipitous decline of sea ice extent is that Arctic Ocean ice has become so thin after years of rapidly rising temperatures in the region, with thick, multi-year ice being replaced by thin, year-old ice that swiftly melts in summer.