Massive Arctic Ice Island Drifting Toward Shipping Lanes
(Click to enlage) A lake of meltwater on the surface of the Petermann Glacier in this July 6, 2009 handout photo. (Credit: Greenpeace, Reuters)
The biggest Arctic “ice island” to form in nearly 50 years — a 250-square-kilometre behemoth described as four times the size of Manhattan — has been discovered after a Canadian scientist scanning satellite images of northwest Greenland spotted a giant break in the famed Petermann Glacier.
(From The Vancouver Sun / by Randy Boswell) — About one-quarter of Petermann’s 70-kilometre-long floating ice shelf has split from the main glacier and is now drifting in a fiord toward open water. It will eventually track a route south, toward Canadian shipping lanes along the Baffin Island and Newfoundland coasts, as do most icebergs calved from Greenland’s shoreline glaciers — including the one that struck and sank the Titanic in 1912.
Environment Canada’s Trudy Wohlleben, a researcher with the Canadian Ice Service, reported the birth of the colossal ice island on Thursday to a U.S. expert conducting a study on ice movement in Nares Strait — the narrow sea passage between Greenland and Canada’s Ellesmere Island.
University of Delaware researcher Andreas Muenchow confirmed and announced the discovery on Friday, describing the ice island’s thickness of more than 200 metres in some places as “half the height of the Empire State Building.”
The new ice island dwarfs a 29-square-kilometre one that broke away from the Petermann Glacier in 2008 and forced the Canadian Ice Service to closely monitor its movement last summer near shipping routes at the south end of Baffin Island.
The threat subsided after the ice island broke into smaller pieces that drifted throughout the waters of the Eastern Canadian Arctic.
At the time, however, experts had detected a large crack in the Petermann Glacier that they suspected might produce a much, much bigger ice island — a prediction now proven correct.
“The fresh water stored in this ice island could keep the Delaware or Hudson rivers flowing for more than two years,” Muenchow said in a statement. “It could also keep all U.S. public tap water flowing for 120 days.”
To give some Canadian comparisons, the free-floating block of ice is considerably larger than B.C.’s Saltspring Island, about half as big as the Island of Montreal and almost the exact size of Newfoundland’s Fogo Island.
“In Nares Strait, the ice island will encounter real islands that are all much smaller in size,” Muenchow stated. “The newly-born ice island may become land-fast, block the channel, or it may break into smaller pieces as it is propelled south by the prevailing ocean currents. From there, it will likely follow along the coasts of Baffin Island and Labrador, to reach the Atlantic within the next two years.”
Muenchow said the last time the Arctic produced an ice island larger than this one was in 1962, when a 400-sq.-km piece of the Ward Hunt Ice Shelf broke away from north coast of Ellesmere Island.
Earlier this summer, the Jakobshavn Glacier — its ocean outlet located near the town of Ilulissat on Greenland’s west coast —lost a seven-square-kilometre section of its leading edge.
The collapse of several Arctic ice shelves in recent years has kept the Canadian Ice Service on alert for possible threats to ships and oil exploration activity.
In 2005, a 66-square-kilometre chunk of the Ayles Ice Shelf on Ellesmere Island’s northern coast broke free and began drifting south. Federal scientists kept a close watch on the resulting Ayles Ice Island as it tracked a worrisome route toward the Beaufort Sea, a relatively busy region in summer for shipping and oil-and-gas exploration.
But in August 2007, the five-by-15-kilometre slab turned down a dead-end channel between Meighen and Axel Heiberg islands, where it was expected to slowly break up over years and become an anonymous part of the Arctic pack ice.
In 2008, the Ellesmere Island ice shelves experienced unprecedented losses totalling about 200 square kilometres, sending more huge ice chunks drifting through Canada’s Arctic waters.
One of the country’s five remaining Arctic ice shelves — the 4,500-year-old, 50-square-kilometre Markham Ice Shelf — broke completely away from Ellesmere and drifted into the Arctic Ocean, a particularly dramatic sign of how rising temperatures and retreating sea ice were creating what one top scientist called “irreversible” changes to the country’s polar frontier.
