Arctic sea ice extent not quite a low record-breaker: National Snow and Ice Data Center

Here’s how the Arctic sea ice looked Sept. 12. The orange line in extent image (left) and gray line in time series (right) indicate 1979 to 2000 average extent for the day shown. (IMAGE/NSIDC)

On Sept. 10, Arctic sea ice extent was 4.34 million square kilometres, 110,000 sq. km above the 2007 sea ice cover on the same date, says the National Snow and Ice Data Center in Boulder, Colorado.

Earlier this month, scientists from the University of Bremen said the Arctic sea ice extent fell below the 2007 minimum.

“While the University of Bremen and other data may show slightly different numbers, all of the data agree that Arctic sea ice is continuing its long-term decline,” the NSIDC said Sept. 13.

The record minimum Arctic sea ice extent, recorded in 2007, was 4.17 million sq. km. — and that low record hasn’t been yet, according to its scientists.

During the first week of October NSIDC scientists plan to issue a more detailed analysis of this year’s melt season and the state of the sea ice.

The information used by the NSIDC comes from a sensor on the “Defense Meteorological Satellite Program F17” satellite. Its data record goes back to 1979.

Other sea ice data, such as that from the University of Bremen, uses different satellite sensors and other ways of calculations produced different results, the NSIDC says.