Arctic sea ice III: it’s not through melting

NSIDC arctic sea ice extent graph for September 18, 2010

NSIDC Arctic sea ice extent graph for September 18, 2010

On September 15 the US National Snow and Ice Data Center (NSIDC) announced a provisional Arctic sea ice minimum extent of 4.76 million square kilometers, for September 10, based on the five-day-average calculation it uses for that purpose.   However it appears that while sea ice is beginning to grow in the East Siberian Sea, just about everywhere else the ice is still melting or consolidating.  This has led to a “double dip” in the past few days, which is currently visible in the NSIDC’s chart.

At this point we don’t know what will happen to the sea ice extent. Of course it’s bound to grow back rapidly pretty soon because so much of it melted during the summer season and there’s nothing much left that is likely to melt or consolidate. This is bringing the 2010 melt season to an interesting close.