An effect of the increased global warming

Oct 5, 2007 08:34 GMT  ·  By

The decline of the severe ice shelf coming with the global warming, a process that has been observed in the last years in Antarctica and Greenland, is more and more prominent in the North Pole area.

In Aug. 13, 2005, the giant Ayles Ice Shelf, the size of Manhattan (16 x 5 km; 10 mi x 3 mi), has broken out free from the Ellesmere Island's ice shelf, just 800 km (500 mi) south of the North Pole, in the Canadian Arctic. The wandering ice island had in May 2007 a medium thickness of 42-45m (138-148ft) (as much as the height of a 10-story building), being the largest ice break in the area in the last 30 years.

Now, the giant Ayles Ice Island moving off Canada's northern shores has split in two, much earlier than normal.

In a season of record summer melting, the two chunks have rapidly moved through the water, one moving 98km (61 miles) in a week and many fear they could go westward into the oil and gas installations off Alaska.

"The island became more vulnerable to breaking up with the warmer temperatures in more southerly latitudes, together with having less protection from the smaller amounts of surrounding sea-ice. It's relatively unusual for the ice island to drift so far south so quickly - many ice islands in the past have stayed within the Arctic Ocean, or within the northern parts of the Queen Elizabeth Islands," Dr. Luke Copland of the University of Ottawa told BBC.

"The low sea-ice conditions this year have played a role. The sea-ice normally blocks ice inflow into the Queen Elizabeth Islands, but with less ice this year it has made it easier for the Ice Island to make its way in."

While ice islands in the past lasted for over 50 years or more in the Arctic Ocean, this one is forecast to last less than one decade.

"Ultimately, the ice island should break up faster because of the warmer temperatures - I'd be surprised if it lasted more than a decade or so."

2007 is the year with the record smallest area of ice cover in the Arctic: 4.13 million sq km (1.59 million sq miles) on 16th of September. The previous record, in 2005, was of 5.32 million sq km.

"We are losing remarkable features of the Canadian North that have been in place for many thousands of years," said Warwick Vincent of Laval University.

"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. You could stand at one edge and not see the other side, and for something that large to move that quickly is quite amazing," he said.