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Arctic sea ice all but gone
A leading Canadian ice scientist has challenged studies claiming Arctic sea ice is making a modest comeback from an unprecedented retreat in 2007.
David Barber, research chair in Arctic System Science at the University of Manitoba, said the once-30-foot-thick permanent ice that is vital to the northern ecosystem has merely been replaced by thin “rotten” ice that is unable to support the weight of polar bears.
“Contrary to what satellites recently suggested, we are actually speeding up the loss of the remaining, healthy, multiyear sea ice,” he said.
His findings are about to be published in the journal Geophysical Research Letters and argue the change in Arctic ecosystems is accelerating and that sea navigation through the polar waters during the summer and fall will occur much sooner than many have predicted.
Barber said the satellite images tracking the extent of Arctic ice fail to show how weak the older, thicker ice core has become.
Back from an expedition to the Beaufort Sea, Barber said his team of researchers was expecting to find multiyear sea ice.
“Unfortunately, what we found was that the multiyear ice has all but disappeared,” he said.
The permanent ice was easily pierced by the research ship and, within five minutes of reaching what was thought to be stable ice, the scientists watched the “entire ice floe break up in pieces.”
The U.S. National Snow and Ice Data Center, which tracks the Arctic ice cover, reported in 2007 that the sea ice was reduced to about 1.1 million square miles in September from 3.6 million square miles the previous winter,
Multiyear ice at 19 percent Barber said multiyear sea ice, which once covered 90 percent of the Arctic basin, is now down to about 19 percent and is only 6.5 feet thick at most.
He said the satellite images from 2008 and 2009, which led some to believe that global warming was reversing, “gave us only part of the story.”
Barber said polar bears are now confined to a small fringe of where the multiyear sea ice exists.
He warned that opening the Arctic to international shipping would worsen the situation if freighters brought with them new contaminants.
A new Arctic road map released by the U.S. Department of the Navy lays out a five-year strategic plan to expand fleet operations into the Arctic in expectations that the Arctic Ocean will be open water by summer 2030.
The plans talks about “strong partnerships” with other Arctic nations, suggesting the Arctic may be opened up to increased resource development, research, tourism and a new global transportation system.
“These developments offer opportunities for growth, but also are potential sources of competition and conflict for access and natural resources,” said the document, signed by Admiral Jonathan W. Greenert, vice chief of U.S. Naval Operations.
—Gary Park
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