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.
(NASA)

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