http://hisz.rsoe.hu/alertmap/woalert_read.php?cid=14992&lang=engGiant fractures have been cracking open the ice in the Beaufort Sea in recent weeks creating extraordinary stretches of open water and giving researchers from around the world a first-hand look at the Arctic meltdown. "It's shocking to see," says David Barber, a climate specialist at the University of Manitoba. He is heading an international project, involving more than 200 researchers from 15 countries, on the Amundsen, a Canadian Coast Guard ship over-wintering in the Beaufort. "The fractures are huge," says Barber, who recently returned from the Amundsen and says some cracks are more than 100 kilometres across. "We drove our ship down of one of them and you couldn't see the sides of it." The Canadian Ice Service has posted a satellite image of one "massive fracture" on its website, along with an animation showing huge fissures opening and giant slabs of ice peeling away west and north of Banks Island over the last five weeks. Stretches of open water, known as leads, normally form in the Beaufort in winter as thick, old ice grinds past much thinner first-year ice. Barber says he has never such large fractures and so much open water in December and January. He says the phenomenon is tied to the loss of Arctic ice last summer, that "stunned" scientists as the ice retreated 40 per cent below normal, to the lowest level since satellite measurements began in 1979.
There is now so little thick, multi-year ice left, that it is being blown around the Beaufort "like Styrofoam in a bathtub," says Barber. As the thick older ice moves it pulls away from the thin new ice creating fractures and large areas of open water. The $40-million research initiative on the Amundsen is part of the International Polar Year. Barber says the researchers could not have picked a more interesting winter to spend in the Beaufort, but says the changes they are documenting are "disturbing." Not only is the ice fracturing, but he says storm tracks are changing as weather systems are drawn in over the open water and fed by heat being released by the seawater. And thick multi-year ice, which the researchers are tracking with beacons, is moving at up to 30 nautical miles a day, much faster than normal. If the trend continues, he and other scientists predict the Arctic could be ice free in the summer months by 2020, plus or minus 10 years. That means Arctic summer ice, which has capped the planet for more than a million years, might be gone by 2010, says Barber.
The implications extend far beyond the Arctic, and the possibility of shipping routes opening in the North. Weather across the Northern Hemisphere is impacted by what happens in the Arctic and the northern ice plays a critical role in controlling Earth's thermostat. Arctic ice reflects close to the 95 per cent of solar radiation that hits it. Once the ice melts away, seawater absorbs the heat instead, later releasing it back to the atmosphere, a process that will speed global warming. The phenomenon is already at play in the Beaufort. Barber says the extra heat absorbed by the sea water last summer delayed the formation of new ice last fall by many weeks. And the heat is still being released as storms churn up open water, creating unusually balmy winter weather, he says, noting the temperatures off Banks Island hit -9 C when he was on the Amundsen in December. )
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