London: Scientists have for the first time mapped Antarctica sans ice.
An international team, led by British Antarctic Survey, has revealed the soaring mountain peaks and the deep valleys hidden beneath Antarctica`s ice sheet in its map, using decades of data acquired by planes, ships and satellites.
The map, BEDMAP2, gives the close-up view of Antarctica without its ice, say the scientists, adding that it provides critical information for understanding how the white continent might respond to climate change.
The Australian Antarctic Division and the Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC) played a major role in collecting some of this data over three seasons of aerial radar surveys out of Casey and through the Antarctica`s Gamburtsev Province project (AGAP) in 2008-09.
The map reveals deep troughs within the interior of the continent, where the bedrock is far below sea level, and rugged mountain ranges peaking at 3000 metres -- the height of
European Alps -- but hidden below over 1000 metres of ice.
Team member Dr Roland Warner said the map will enable scientists to use real bedrock to apply the physics of how ice flows across Antarctica. "These improvements are central
to more accurate predictions of how Antarctica will respond to climate change and what that means for future sea level."
Dr Warner says that when radar pulses penetrate the ice sheet and hit bedrock, they bounce back, and these returning echoes can be used to measure the thickness of the ice and hence the depth of the bedrock.
More survey data is needed to improve the detail of BEDMAP2 in two large regions; in the Australian Antarctic Territory between the Gamburtsev Mountains and the coast near
Davis Station, and south of the Shackleton mountain range towards the South Pole, say the scientists.