Massive Arctic ice shelf breaks away
By David Ljunggren
OTTAWA (Reuters) - A huge 19 square mile (55 square km) ice shelf in Canada's northern Arctic broke away last month and the remaining shelves have shrunk at a "massive and disturbing" rate, the latest sign of accelerating climate change in the remote region, scientists said on Tuesday.
They said the Markham Ice Shelf, one of just five remaining ice shelves in the Canadian Arctic, split away from Ellesmere Island in early August. They also said two large chunks totaling 47 square miles had broken off the nearby Serson Ice Shelf, reducing it in size by 60 percent.
"The changes ... were massive and disturbing," said Warwick Vincent, director of the Centre for Northern Studies at Laval University in Quebec.
Temperatures in large parts of the Arctic have risen far faster than the global average in recent decades, a development that experts say is linked to global warming.
"These substantial calving events underscore the rapidity of changes taking place in the Arctic," said Derek Mueller, an Arctic ice shelf specialist at Trent University in Ontario.
"These changes are irreversible under the present climate and indicate that the environmental conditions that have kept these ice shelves in balance for thousands of years are no longer present," he said in an e-mailed statement from the research team sent late on Tuesday.
Mueller said the total amount of ice lost from the shelves along Ellesmere Island this summer totaled 83 square miles -- more than three times the area of Manhattan island.
The figure is more than 10 times the amount of ice shelf cover that scientists estimated on July 30 would vanish from around the island this summer. Continued...