Sea ice in the Arctic Ocean appeared to reach its lowest extent for the year in mid-September, with an amount of ice significantly higher than last years record but still in line with long-term trends that show the ice in rapid, steady decline.
On Sept. 13, the amount of Arctic sea ice fell to about 1.97 million square miles, according to the Boulder, Colo.-based National Snow and Ice Data Center. Sea ice melts in the summer and refreezes in winter. NSIDC scientists reported that the ice has since begun its annual fall and winter regrowth.
This year's minimum extent – the term used to describe the area of the Arctic Ocean covered by sea ice – was "notably higher" than the record low extent the NSIDC recorded last year, when the minimum reached about 1.32 million square miles on Sept. 16, 2012.
That doesn't mean that the trend of retreating sea ice, which has been observed since satellite observations of the Arctic began more than 30 years ago, has reversed. Rather, this year's higher minimum extent is only a "temporary reprieve," the NSIDC said, and part of a long-term trend that includes ups and downs due to natural variation in weather patterns and conditions in the Arctic Ocean.
"While this is a very welcome recovery from last year's record low, the overall trend is still decidedly downwards," noted NSIDC director Mark Serreze, who added that "we could be looking at summers with essentially no sea ice on the Arctic Ocean a few decades from now."
The areas of the Arctic that saw "considerably higher sea ice extent" this year included the Beaufort, Chukchi and East Siberian sea regions, as the ice edge was located several hundred miles farther south than last year, the NSIDC noted.
NSIDC scientists pointed out Friday that the minimum extent number they reported could still change, as winds or other Arctic weather conditions could tear apart portions of the ice and push the number still lower.
The center plans to release a full analysis of this year's Arctic melting season in October, once complete data from September is available.http://www.b.weather.com/news/science/environment/arctic-sea-ice-melts-lowest-extent-2013-20130920
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