Sea ice retreat heavy, but not record-breaking this year

When you saw all those chunks of ice floating around in Frobisher Bay last week, you might have thought that Arctic sea ice is thriving and in no danger of melting away.

If so, you would have been wrong, says Mark Serreze, an environmental scientist at the National Snow and Ice Data Centre in Boulder, Colorado.

Satellites show that little ice remains between Baffin Island and Greenland, he said last week in a telephone interview.

All that ice that ended up in Frobisher Bay broke away from melting glaciers in Greenland, then floated down Baffin Bay to the mouth of Frobisher Bay, where it was pushed towards Iqaluit by winds from the south.

When the remaining amount of Arctic ice cover is recorded in September, Serreze said it's not likely to be a record-breaking low.

But this year's measurements will likely reveal the second- or third-lowest Arctic ice cover ever, he said.

Although Arctic sea ice continued its downward trend last month, he said satellites did not detect anything close to the loss of ice cover noted during the summer of 2007.

Part of the reason is that this year's temperatures were cooler during the last two weeks of July, especially north of Alaska.

Now that the amount of sunlight reaching the high latitudes is shrinking, the rate of sea ice decline should soon start to slow.

However, the continuing Arctic sea ice melt is part of the same warming trend that recently saw two large chunks off break off the Ward Hunt ice shelf in northern Ellesmere Island, Serreze said.

The break is the largest on record since 2005.

Two chunks, which broke off between July 22 and 24, formed two islands of ice, one measuring four to five square kilometres and the other 14 square kilometres.

The ice shelves, made of thick ice floating on the ocean but attached to land, formed more than 4,000 years ago.

Scientists say about 90 per cent of Ellesmere's ice shelves have calved off over the past 100 years.