Antarctic ice sheets stable since millions of years

The ice sheets of central Antarctica have been stable for millions of years when conditions were warmer than now, a new research has found.

Researchers from the Universities of Edinburgh and Northumbria studied rocks on slopes of the Ellsworth Mountains in Antarctica, whose peaks protrude through the ice sheet.

However, the scientists are concerned that ice at the coastline is vulnerable to rising temperature, though the discovery points towards the long-term stability of Antarctica's ice sheet.

Scientists calculated that the mountains have been shaped by an ice sheet over a million-year period, beginning in a climate some 20 degrees warmer than at present.

"The preservation of old rock surfaces is testimony to the stability of at least the central parts of the Antarctic ice sheet -- but we are still very concerned over other parts of Antarctica amid climate change," said David Sugden, professor at University of Edinburgh.

The last time such climates existed in the mountains of Antarctica was 14 million years ago when vegetation grew in the mountains and beetles thrived, the paper published in Earth and Planetary Science Letters noted.

This time marked the start of a period of cooling and the growth of a large ice sheet that extended offshore around the Antarctic continent.

Glaciers have subsequently cut deep into the landscape, leaving a high-tide mark -- known as a trimline -- in the exposed peaks of the Ellsworth range.

The extended ice sheet cooled the oceans and atmosphere, helping form the world of today, researchers stated.

--IANS

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