Warm ice
Arctic ice melting at alarming rate
Changes scientists didn't expect for another 50 years are happening now, research suggests
Ed Struzik, Canwest News Service
Published: Tuesday, April 22, 2008
Ice was the last thing David Barber was worried about when he and an international team of scientists made plans last year to have their research icebreaker frozen into the Beaufort Sea for the winter.
But when the Amundsen sailed into the western Arctic in November, the ice that normally begins to take hold in October hadn't even begun to gel.
"Even by mid-December, the southern Beaufort Sea was still wide open," said Barber, a University of Manitoba sea ice physicist and chief scientist aboard the Amundsen. "That's over a month longer than the time freeze-up normally occurs."
Barber and his colleagues got an even bigger surprise when they sailed north into M'Clure Strait, the main channel connecting the Northwest Passage to the western Arctic. The strait is legendary as a gateway for thick, rock-hard, multi-year ice that piles in from the Beaufort Sea, but Barber and his colleagues found nothing but clear sailing.
"It was surreal," he said. "The weeks spent on the ship were some of the most remarkable of my career. The multi-year pack ice had migrated about 150 miles (240 kilometres) north from where it has traditionally been located. So the ice-associated, high-pressure system that traditionally forms over the southern Beaufort at this time of year was displaced.
"All that cyclonic activity that was drawn in by the warm, open water not only made for some rough sailing, it also put more heat into the air, keeping the local climate warmer than usual."
Barber isn't alone in wondering whether this winter signals the climatic tipping point that many scientists have been anticipating. That's the moment in time when sea ice in the Arctic becomes so thin and vulnerable that the ice produced each winter can no longer keep up with the spring and summer melts.
Many scientists now believe that when this happens, the world will enter a new era of global change -- one that no one really understands, but that will likely have an enormous impact on the climate of the rest of the world.
Up until last summer, most scientists didn't expect that to occur for another 50 or 60 years. Even the most daring weren't willing to wager that it would happen in 15 years.
But this winter's unexpected developments in the Beaufort Sea suggest that all bets are off. Waters that used to lose 10,000 square kilometres a year in ice cover, according to scientists, currently lose at least eight times that amount. Now, some scientists are speculating that the Arctic could be seasonally ice-free in less than a decade.
"The ice is no longer growing or getting old," says John Falkingham, chief forecaster for the Canadian Ice Service, the Environment Canada agency that helps ships find a way through the Northwest Passage and other parts of the Arctic.
Cold as it was this winter in the Arctic and most parts of Canada, it wasn't enough to temper the heat that warmed the ocean and melted so much ice last summer. By the middle of last September, scientists recorded a decline of almost 50 per cent of the normal ice cover. By way of comparison, the area of sea ice lost was equivalent to 10 United Kingdoms.
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