NSIDC: Arctic sea ice extent for June 2008 is close to that for 2007, which went on to reach the lowest minimum since at least 1979. More notably, however, satellite data indicate that melt began significantly earlier than last year over most of the Arctic Ocean. The large area of the Arctic Ocean covered by first-year ice (described in our June analysis) coupled with the early onset of melting may mean more rapid and more severe summer ice retreat than last year.
Commentary: Although Stan Jacobs of Columbia University's Lamont Dougherty Earth Observatory has long said that Antarctica is the wild card in global climate change the Arctic region is emerging as a more important indicator of warming since its mean temperature is rising faster than Antarctica. This is due to the fact that there is a greater mass of land in the northern hemisphere which heats air faster than the oceans, more prominent in the southern hemisphere.
With approximately 23 ft of sea level rise locked up in Greenland, more rapid melting there and along the coastlines of northern Canada, Alaska, Russia, and Scandinavian countries it is vitally important to keep watch on the Arctic.
According to Gwladys Fouché in Longyearbyen, writing for the Guardian.co.uk, on Tuesday August 28, 2007, "The North-West Passage – the sea route running along the Arctic coastline of North America, normally perilously clogged with thick ice – is nearly ice-free for the first time since records began.
"Since August 21 the North-West Passage is open to navigation. This is the first time that it happens," Nalan Koc, head of the Norwegian Polar Institute's climate change programme, told reporters in Longyearbyen, a town in the Arctic archipelago of Svalbard.
"The Arctic ice sheet currently extends on 4.9m square kilometres. In September 2005 it measured 5.3m square kilometers."
Koc was quoting research from the US National Snow and Ice Data Centre, where scientists monitor the surface of the Arctic ice sheet at regular intervals. Last week they noted "the imminent opening" of the North-West Passage."
Ref.: www.guardian.co.uk/environment/2007/aug/28/climatechange.internationalne...
"Analysts confirm that the passage is almost completely clear and that the region is more open than it has ever been since the advent of routine monitoring in 1972," they said in research conclusions published on the centre's website.
The news is yet another milestone showing that the Earth is warming up. The route was first navigated in the early 1900s by the Norwegian explorer Roald Amundsen, who later beat Robert F Scott in the race to the south pole in 1911. Amundsen and his crew took nearly two years to pick their way through a labyrinth of narrow lanes of open water and thick ice. Now it would be comparatively plain sailing.
It has long been expected that Arctic sea routes including the North-West Passage and its north-east counterpart along the coast of Siberia will become more passable as the Earth's temperature climbs.
