Changes scientists didn't expect for another 50 years are happening now, research suggests

Canwest News Service, By Ed Struzik, April 22

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.

[...]

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.

[...]

What made last year's meltdown even more eye-popping was the loss of ice in places where historically it has never retreated. M'Clintock Channel, the so-called mortuary for old, multi-year ice, was almost completely open. And Viscount Melville Sound, the place where new ice is born, was down to half its summer ice cover. That appears to be why this winter's deep freeze wasn't enough to prevent the dramatic events that unfolded in the Beaufort Sea later in the winter.

[...]

"Theoretically, we could see an Arctic that is ice-free in summer months a lot sooner than most people previously thought. Some people think that it could happen in five or six years."

Putting that into perspective, Barber notes that the Arctic hasn't been seasonally ice-free for at least the past 1.1 million years.

Study: Expect Faster Melting, and a 45% Increase in Rate of Sea Level Rise

The Daily Green, By David Shapley, June 12

Another study adds weight to the conclusion that Greenland's ice sheet is melting faster than predicted by the United Nations, and that sea level could rise faster than predicted around the world.

The International Polar Year study, by Sebastian H. Mernild of the University of Alaska-Fairbanks, was published in Hydrological Processes.

Mernild's team's model showed a doubling of freshwater runoff, in the form of melting and iceberg calving, from Greenland by the end of this century.

That level of melting would result in an annual rise of sea levels 45% greater than previously predicted – 1.6 millimeters a year, rather than 1.1. Another recent study predicted that sea levels would rise two times as fast as previously thought because of the rapid melting of Greenland.