Monday, March 9, 2009
Maybe new clues to climate change?
This was concluded last week.
EXPLORING THE SUBGLACIAL GAMBURTSEV MOUNTAINS
'Ghost peaks' mapped under ice
By Jonathan Amos
Science reporter, BBC News http://news.bbc.co.uk/2/hi/science/nature/7908824.stm
"The scale of the AGAP project required international co-operation
Scientists have completed their mission to map one of the most extraordinary mountain ranges on Earth.
Researchers believe the Gamburtsevs would have been the starting point for the great glaciers that eventually spread out to cover the entire polar region when it was plunged into a deep freeze more than 30 million years ago.
In their data, scientists hope to pinpoint the best place to drill a core from the ice. Ancient air trapped in the in snow layers as they were laid down could provide remarkable new insights into the climate history of Earth.
"At the moment, it is like the first page of a book. Up until now we just had an ambitious plan. Now we have all this remarkable data to pore over," Dr Ferraccioli.
The Gamburtsevs are a set of peaks equal in size to the European Alps, but they are hidden deep under the ice in the middle of the Antarctic continent.
The survey data gathered by the multi-national team working in harsh, sub-zero temperatures will help resolve the mystery of why the range exists at all.
Their presence, when first discovered in the 1950s, was totally unexpected.
Scientists thought the interior of the continent would be relatively flat.
Modern-day remote-sensing technology reveals quite the opposite - a very jagged landscape, albeit buried under up to 4km of ice.
"We can confirm they are there; we've seen them under the ice," said Dr Fausto Ferraccioli from the British Antarctic Survey.
"Not only are they similar in dimension to the European Alps, but they are also similar in aspect: we see very sharp peaks and valleys which are remarkably similar to the Alps themselves," he told BBC News.
"It all adds to the mystery - from the tectonic perspective of how these mountains were created; and from the glacial history perspective of how the East Antarctic ice sheet was formed and didn't erode these peaks."
The AGAP (Antarctica's Gamburtsev Province) project comprised scientists, engineers, pilots and support staff from the UK, the US, Germany, Australia, China and Japan.
They established two field camps deep in the Antarctic interior.
"The temperatures at our camps hovered around -30C, but three kilometres beneath us at the bottom of the ice sheet we saw liquid water in the valleys," explained AGAP US co-leader Dr Robin Bell, of the Lamont-Doherty Earth Observatory at Columbia University, New York, US.
Aircraft swept back and forth across the ice, mapping the shape of the sub-glacial mountains using ice-penetrating radar.
Other instruments measured the local gravitational and magnetic fields.
Some 120,000km were flown, the equivalent of three trips around the globe. In total, over 20% (one-fifth) of the East Antarctic Ice Sheet was explored."
The link is for the whole article.