More evidence of global warming.
By Charmaine Noronha | The Associated Press, September 4, 2008
TORONTO – A chunk of ice shelf nearly the size of Manhattan has broken away from Ellesmere Island in Canada’s northern Arctic, another dramatic indication of how warmer weather is changing the polar frontier, scientists said Wednesday.
Derek Mueller, an Arctic ice shelf specialist at Trent University in Ontario, said the 4,500-year-old Markham Ice Shelf separated in early August and the 19-square-mile shelf is adrift in the Arctic Ocean.
“The Markham Ice Shelf was a big surprise because it suddenly disappeared,” he said. “We went under cloud for a bit during our research and when the weather cleared up, all of a sudden there was no more ice shelf. It was a shocking event that underscores the rapidity of changes taking place in the Arctic.”
Mueller also said two large sections of ice detached from the Serson Ice Shelf, shrinking that ice feature by 47 square miles – or 60 percent. The Ward Hunt Ice Shelf has continued to break up, losing an additional eight square miles, he said.
Formed by accumulating snow and freezing meltwater, ice shelves are large platforms of thick, ancient sea ice that float on the ocean’s surface but are connected to land.
Ellesmere Island was entirely ringed by a single enormous ice shelf until it broke up in the early 1900s. All that is left today are the four much smaller shelves that together cover nearly 300 square miles.
The loss ice shelves means rare ecosystems are on the brink of extinction, said Warwick Vincent, director of Laval University’s Centre for Northern Studies.