Central parts of Antarctica's ice sheet have been stable for millions of years, from a time when conditions were considerably warmer than now, research suggests.

The study of mountains in West Antarctica will help scientists improve their predictions of how the region might respond to continuing climate change. Its findings could also show how ice loss might contribute to sea level rise.

Although the discovery demonstrates the long-term stability of some parts of Antarctica's ice sheet, scientists remain concerned that ice at its coastline is vulnerable to rising temperatures.

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

By mapping and analysing surface rocks - including measuring their exposure to cosmic rays - researchers calculated that the mountains have been shaped by an ice sheet over a million-year period, beginning in a climate some 20C warmer than at present.

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. Antarctica's climate at the time would be similar to that of modern day Patagonia or Greenland.

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 say. Their study is among the first to find evidence for this period in West Antarctica.

The research, published in Earth and Planetary Science Letters, was done in collaboration with the Scottish Universities Environmental Research Centre. It was funded by the UK Natural Environment Research Council and supported by British Antarctic Survey.

Professor David Sugden, of the University of Edinburgh's School of GeoSciences, said: "These findings help us understand how the Antarctic Ice Sheet has evolved, and to fine-tune our models and predict its future.

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."

Tweet

Antarctic ice rift spreads
Swansea UK (SPX) May 04, 2017
The rift in the Larsen C ice shelf in Antarctica now has a second branch, which is moving in the direction of the ice front, Swansea University researchers revealed after studying the latest satellite data. The main rift in Larsen C, which is likely to lead to one of the largest icebergs ever recorded, is currently 180 km long. The new branch of the rift is 15 km long. Last year, res ... read more

Related Links
University of Edinburgh
Beyond the Ice Age

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only