Australia’s ABC news reports:
Scientists hope to discover how warm water is reaching one of the world’s largest glaciers, causing it to melt rapidly.
Lead author Steve Rintoul said it was the first time scientists had been able to test the hypothesis that warm ocean waters were driving the glacier’s thinning.
“We knew the Totten has been thinning faster than other glaciers in East Antarctica, but nobody has known exactly why until we took these measurements,” he said.
“We found that warmer ocean water is reaching the cavity through this channel at temperatures capable of melting the ice shelf at the point where it meets ground.
Dr Rintoul said it was important to be able to predict the Totten glacier’s future behaviour, because it contained enough sea ice to raise global sea levels by about 3.5 metres.
“So the real importance of the research is that it helps provide some clues about how sea level might change in the future.”
The publication of the research today comes as scientists make their way back to the Totten glacier, where they hope to find more clues about what controls the amount of warm water reaching the glacier.
A team of about 30 scientists, technicians and PhD students left Hobart on December 8 and plan to arrive at the glacier in late December.
Dr. Rintoul said their goal was to learn more about the pathways that bring the warm water up from the deep ocean.
“Understanding the physical processes delivering heat to the ice shelf will help us assess the vulnerability of the East Antarctic ice sheet to future changes in the Southern Ocean,” he said.
“What we have shown is that warm water reaches the glacier. What we need to know is what’s going to happen in the future.
Dr. Tas van Ommen from the Australian Antarctic Division said it would be concerning to see an increase in the Totten glacier’s natural melt rate.
“If its natural melt rate was to increase because of changes in ocean circulation, that would then add to the sea level rise that we see from glaciers already melting in Antarctica, particularly in the West.
“So we are concerned to track that and to be able to predict what might happen in the future.”