NSIDC stunner: Arctic ice at “Likely Record-Low Volume”

Looks like the Arctic may have set a record this year after all. The National Snow and Ice Data Center (NSIDC) said today that Arctic sea ice volume likely hit a record low in 2008. They reconfirmed that the sea ice extent (or area) “dropped to the second-lowest level since satellite measurements began in 1979″ and that “Despite cooler temperatures and ice-favoring conditions, long-term decline continues.”

But the big news was the announcement about ice volume, since that has huge implications for future ice loss:

NSIDC Research Scientist Walt Meier said, “Warm ocean waters helped contribute to ice losses this year, pushing the already thin ice pack over the edge. In fact, preliminary data indicates that 2008 probably represents the lowest volume of Arctic sea ice on record, partly because less multiyear ice is surviving now, and the remaining ice is so thin.” [See Figure — Click to enlarge.]

This figure compares ice age in September 2007 (left) and September 2008 (right). It shows the sharp increase in thin first-year ice (red) and the decline in thick multi-year ice — both “second-year ice” (orange) and “third-year and older ice” (yellow). “White indicates areas of ice below ~50 percent, for which ice age cannot be determined.”

NSIDC explains what prevented 2008 from beating the 2007 record low in ice extent:

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