Boffins tackle great dilemma
ABOUT 50 glaciologists, geologists, geophysicists and Antarctic ice sheet modellers from across the world are in Hobart this week to discuss one of sealevel rise forecasters’ greatest dilemmas.
Jacqueline Halpin, organiser of the three-day meeting, said sea-level rise predictions could be a lot more detailed if scientists were able to take the temperature of Antarctica’s rocks beneath the melting ice sheets.
Dr Halpin, a geologist with the Antarctic Gateway Partnership, said researchers had gained some knowledge of ocean and atmospheric temperatures around Antarctica and their influence on ice sheet melting.
But access to Antarctica’s rocky land mass, to study temperature variations across the continent, has so far been denied by the ice sheets, as thick as 3-4km.
“Ice cover and the logistical difficulties of drilling into the Antarctic bedrock means scientists have not yet been able to accurately establish the underlying geothermal heat flow, or temperature, of the continent,” Dr Halpin said.
She said participants were discussing the possibility of using specialised drills that could reach Antarctic bedrock, as well as alternative ways of gauging land temperature.
Experts from the US, Britain, China, Japan, Belgium, Ireland, New Zealand and interstate universities and NASA, with satellite thermal imaging expertise, are looking at the issue, as well as local researchers from the Institute for Marine and Antarctic Studies, the Antarctic Gateway Partnership, Antarctic Climate and Ecosystems Cooperative Research Centre and the Australian Antarctic Division.
“We know that heat flow varies regionally across the continents due to differences in their geology and plate tectonic history,” Dr Halpin said.
“In Antarctica, 99 per cent of the continent is covered in ice, so geothermal heat flow patterns are difficult to map, but hotspots may significantly affect how ice flows and melts in different areas.
“Improving our knowledge of such variations will help fine-tune predictions of how the Antarctic ice sheet will respond in the future.”