Thaindian News

Washington, April 22 (IANS) Melting glaciers and ice caps on Canadian Arctic islands play a much greater role in sea-level rise than scientists previously suspected,

For instance, the 550,000-square-mile Canadian Arctic Archipelago contains some 30,000 islands. Between 2004 and 2009, the region lost the equivalent of three-quarters of the water in Lake Erie, found a study led by the University of Michigan.

Warmer-than-usual temperatures in those years caused a rapid increase in the melting of glacier ice and snow, said Alex Gardner, research fellow in Atmospheric, Oceanic and Space Sciences at Michigan, who led the project, reports the journal Nature.

“This is a region that we previously didn’t think was contributing much to sea-level rise,” Gardner said. “Now we realize that outside of Antarctica and Greenland, it was the largest contributor for the years 2007 through 2009,” a Michigan statement quoted him as saying.

“This area is highly sensitive and if temperatures continue to increase, we will see much more melting,” added Gardner.

Ninety-nine percent of all the world’s land ice is trapped in the massive ice sheets of Antarctica and Greenland.

Despite their size, they currently only account for about half of the land-ice being lost to oceans. This is partly because they are cold enough that ice only melts at their edges.

The other half of the ice melt adding to sea-level rise comes from smaller mountain glaciers and ice caps such as those in the Canadian Arctic, Alaska, and Patagonia.

The study underscores the importance of these many smaller, often overlooked regions, Gardner said.

During the first three years of the study, from 2004 through 2006, the region lost an average of seven cubic miles of water per year. That increased dramatically to 22 cubic miles of water — roughly 24 trillion gallons — per year during the latter part of the study.

Over the entire six years, this added a total of one mm to the level of the world’s oceans. While that might not sound like much, Gardner says that small amounts can make big differences.

In the study, a one-degree increase in average air temperature resulted in 15 cubic miles of additional melting. Because the study took place over just six years, the results don’t signify a trend.

The United Nations projects that the oceans will rise by a full meter by the end of the century. This could have ramifications for tens of millions of people who live in coastal cities and low-lying areas across the globe.