An ancient ice shelf the size of 11,000 football fields that broke off Ellesmere Island could be dangerous when it starts to drift in the spring, a scientist says.
The collapse of the ice island's northern coast represents the largest breakup of its kind in the Canadian Arctic in 30 years, the head of a new global ice lab at the University of Ottawa said on Thursday.
The collapse of the ice island's northern coast represents the largest breakup of its kind in the Canadian Arctic in 30 years.
Luke Copland, an assistant professor at the school's department of geography, said scientists are surprised at the speed of the collapse of the Ayles ice shelf, about 800 kilometres south of the North Pole. It took less than an hour.
He said the new island formed by the 66-square-kilometre fragment, which could be up to 4,500 years old, could present a serious risk to oil platforms in its drift path in the spring.
At the longest and widest spans, the remains of the Ayles shelf are about 15 kilometres long and five kilometres wide. The fragment is between 30 and 40 metres thick.
Copland learned of the break after an official with the federal government's Canadian Ice Service noticed the change on satellite images and passed it on to him to determine what happened, according to a report by CanWest News Service.
In June, Copland received nearly $206,000 in grant funding from the Canada Foundation for Innovation to create the Laboratory for Cryospheric Research, which will monitor the state of glaciers, climate change and study ice in all of its forms.
A satellite image shows a 66-square-kilometre chunk of ice has broken off Ellesmere Island.
(CBC)
Warwick Vincent of Laval University in Quebec City, who travelled to the new segment, said in 10 years of working in the Arctic, he had never seen such a dramatic collapse.
"It's like a cruise missile has come down and hit the ice shelf," he told CanWest News Service. Vincent is a professor at the university's biology department, where he does ecological research.
The collapse of the Ayles shelf — one of six that still existed in Canada — occurred 16 months ago, on Aug. 13, 2005, but because it is so remote, no one saw it.
Scientists have been combining seismic and satellite data to determine what happened and are now releasing details of the collapse.
The researchers suspect climate change may have played a role in the collapse but said they cannot definitively say it is a result of global warming.
With files from the Canadian Press
The Ayles ice shelf, which is more than 11,000 football fields in size and is located just south of the North Pole, has broken free in the Canadian Arctic. Scientists say that global warming has played a "major" role in the break.

The entire 41 square miles of the shelf broke away from Ellesmere Island at least 16 months ago, and the break was discovered when a satellite took pictures of the region recently.

"This is a dramatic and disturbing event. It shows that we are losing remarkable features of the Canadian North that have been in place for many thousands of years. We are crossing climate thresholds, and these may signal the onset of accelerated change ahead," said Warwick Vincent, a Laval University scientist who studies conditions in the Arctic.

Higher temperatures are believed to have played a significant role in the break, and all 6 shelves in the Canadian Arctic have become at least 90% smaller since they were discovered in the early 1900's.

"It the break is consistent with climate change. We aren't able to connect all of the dots, but unusually warm temperatures definitely played a major role," added Vincent.

Seismographs detected the break and collapse of the shelf in August of 2005. The short amount of time it took for the event to occur has come as a surprise to scientists.

"What surprised us was how quickly it happened. Even 10 years ago scientists assumed that when global warming changes occur that it would happen gradually, so that perhaps we expected these ice shelves just to melt away quite slowly. It's pretty alarming," said head of the University of Ottawa's global ice lab, Luke Copland.