ShareThisIn less than two decades, the Arctic Ocean could be all but ice-free all summer, every summer, which would have potentially devastating implications for the rest of the planet, British researchers say.
An on-the-ground observation sampling of ice thickness, the first of its kind, indicates the Arctic Ocean's frozen cover is rapidly thinning, according to the Polar Ocean Physics Group at the University of Cambridge. The area will be open and navigable during the summer in a decade; in 20 years, summer ice will have all but disappeared.
Three British explorers spent 73 days trekking, skiing and swimming across more than 250 miles of what is normally vast, frozen wasteland off Canada's northern coast -- layers of ice from multiple years forming massive, bluish-white crags stacked on top of each other.
But this year, the ice was younger, thinner and receding quickly: The vast majority of the terrain they covered was less than seven feet thick, indicating it had just frozen last winter, said one of the group, veteran Arctic explorer Pen Hadow.
"We are now getting to the point where it's going to become a seasonal feature only on the face of our planet, and anyone who thinks that is not going to have consequences ... needs to have a rethink," Hadow said.
"It's a wakeup call ... Losing the sea ice cover may be one of the biggest cues that we all get to consider what we might want to do about managing our relationship with the natural world."
Assuming these trends continue, warmer weather will chip away at multi-year ice until the remaining frozen layers break up and eventually become subsumed into the sea.
Summer ice conditions will probably never return to their levels of a couple of decades ago, said Cambridge professor Peter Wadhams, who heads the Polar Ocean Physics Group.
Within 10 years, all that will be left of the masses of ice that used to blanket the North will be an isolated "sort of Alamo of multi-year ice ... and this will itself gradually shrink and disappear," he said.
In an e-mailed statement, Environment Canada said its ice service observed the third-smallest Arctic summer ice minimum area on record this year.
The ripple effects of an ice-free Arctic Ocean are myriad: In the short term, a navigable north would be a boon for the shipping business, and newly opened sea routes would heat up sovereignty debates among polar nations, the researchers said.
Right now, the ice reflects about 85 percent of the heat from the sun -- hundreds of miles of newly open water would absorb all that heat, drastically altering the habitat of ocean-dwelling species. Melting permafrost on the continental shelf would release methane gas, further accelerating global warming, they said.
Exposing that water to the elements would increase its acidity and change global weather patterns previously accustomed to a permanently frozen sheet rather than wide-open ocean.
"You're essentially, for the first time, creating an ocean. Which is not something you want to do as a global experiment, because you cannot take the ocean away," Wadhams said.
"If it's a disaster you cannot put the lid back on again and say, 'Oh, that didn't work out, let's try that again.' You're stuck with what you've done."
(Distributed by Scripps Howard News Service, www.scrippsnews.com.)
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