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Arctic sea ice probably at minimum Minimum sea ice extent for this year will likely be well above last year’s record low; Northwest Passage remains closed to shipping Alan Bailey Petroleum News
The extent of the Arctic sea ice cover has probably reached a minimum for this year, as the hours of daylight and the air temperatures drop in the polar region, the National Snow and Ice Data Center, or NSIDC, has reported. After falling to 1.97 million square miles on Sept. 13 the ice extent now seems set to increase again, NSIDC said.
Although 653,000 square miles above the record minimum extent set last year, this year’s minimum remains below the average minimum extent recorded from 1981 to 2010, NSIDC said.
And this year there have been considerable variations between different Arctic regions. The ice extent was considerably larger than last year in the Chukchi Sea, Beaufort Sea and East Siberian Sea regions, and the Northwest Passage has remained closed thanks to the Canadian Archipelago retaining much more ice than previously. On the other hand, there is less ice this year off the east coast of Greenland, south of Fram Strait, as well as in small areas north of the Kara and Laptev seas, NSIDC said.
NSIDC has characterized its sea-ice minimum report as preliminary and has yet to publish an assessment of how this year’s sea ice conditions have arisen.
Hiatus in warming In another aspect of global climate change, there has been a lively debate recently over observations that since the turn of the century average annual worldwide temperatures have remained relatively stable, rather than appearing to continue on a long-term upward trend. But, while some people have taken this new phenomenon as reason to justify skepticism over global warming, most climate scientists seem confident in their predictions of a greenhouse-gas-driven long-term temperature rise. And scientists have been searching for explanations for the recent hiatus in the warming trend.
According to research published in a recent issue of Nature, a cooling effect in the eastern equatorial Pacific Ocean can closely account for the stabilization of worldwide temperatures in the face of a continuing increase in the carbon dioxide content of the atmosphere. This research shows that the current temperature hiatus is part of natural climate variability linked to ocean temperatures, and that in the longer term global warming will likely continue, the authors of the paper say.
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