(Australian Associated Press)
Scientists have discovered massive underwater lakes beneath the largest glacier in east Antarctica, a find they hope can lead to a better understanding of ice melting rates.
A team of international researchers, including some from the Australian Antarctic Division, has recently returned from an expedition to Totten Glacier.
They spent the summer drilling into the ice and setting off explosive shocks roughly two metres below the surface.
“We placed geophones along the surface to listen to the reflected sound, giving us a picture of what lies beneath the ice,” AAD glaciologist Dr Ben Galton-Fenzi said.
“If there’s bedrock under the glacier, it’s sticky and will move more slowly, but if there’s water or soft sediments, the glacier will move faster.”
They found more water than expected: a network of lakes beneath the glacier, which is 30 kilometres wide and up to two kilometres thick.
Dr Galton-Fenzi said there was enough ice in Totten Glacier to raise sea levels by seven metres but more research was needed to determine the rate at which it could melt as a result of climate change.
“We actually know for a fact that the Totten Glacier is one of the regions that’s changing,” he said.
“We know there’s warm water present under the glacier, so we expect this is one of the regions in east Antarctica that’s going to change first.
“We’re trying to understand the state it is in at the moment, and how rapidly it is going to change in the future.”
Dr Galton-Fenzi said the AAD hopes to learn more about the glacier by drilling into its bed over the next few years.
The recent return of Australia’s Aurora Australis icebreaker marked the end of the summer Antarctic season, where more than 550 expeditioners travelled south with the AAD to work on more than 56 projects.