February 24, 2009

Antarctic Ice Covers Alp-Sized Mountain Range

Scientists said on Tuesday that Antarctica's ice is covering up jagged mountains the size of the Alps, providing new clues about the vast ice sheet that will raise world sea levels if even a fraction of it melts, Reuters reported.

First detected by Russian scientists 50 years ago at the heart of the East Antarctic ice sheet using radar and gravity sensors, the experts made the first detailed maps of the Gamburtsev subglacial mountains.

Fausto Ferraccioli, a geophysicist at the British Antarctic Survey who took part in the research, said not only is the mountain range the size of the Alps, but it looks quite similar to the European Alps with its high peaks and valleys.

"The mountains would probably have been ground down almost flat if the ice sheet had formed slowly," he said.

However, he said the presence of jagged peaks might mean the ice formed quickly, burying the landscape under up to 2.5 miles of ice.

"The maps were the first page of a new book of understanding how ice sheets behave, which in turn could help predict how the ice will react to global warming," Ferraccioli said.

The continent of Antarctica has been swathed in ice for about 35 million years, and contains enough of it to raise world sea levels by about 187 feet if it ever all melted. So even a fractional melt would affect coasts around the globe.

Ferraccioli said any sort of predictive model wouldn't match reality unless they have a basic understanding of how ice sheets work.

Greenhouse gases, mostly emitted from burning fossil fuels, are expected to bring more heatwaves, floods and droughts, and raise sea levels, according to the U.N. panel on climate change.

Experts from Australia, Britain, Canada, China, Germany, Japan and the United States also discovered water below the ice using survey aircraft that flew 75,000 miles.

Robin Bell, of the Lamont-Doherty Earth Observatory at Columbia University, said in a statement: "The temperatures at our camps hovered around minus 22 Fahrenheit, but 2 miles beneath us at the bottom of the ice sheet we saw liquid water in the valleys."

In recent years, many geologists have discovered sub-glacial lakes in Antarctica.

Mountain ranges such as the Alps or the Himalayas formed in collisions between continents. The last time Antarctica was exposed to such forces was 500 million years ago.

Ferraccioli said the Alps are only 50 to 60 million years old, but the sub-glacial mountain range may be as old as 500 million years.


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