SYDNEY - The largest glacier in East Antarctica, containing ice equivalent to a six-metre (20-foot) rise
in global sea levels, is melting due to warm ocean water, Australian scientists said on Monday.
The 120-kilometre (74.4 mile) long Totten
Glacier, which is more than 30 kilometres wide, had been thought
to be in an area untouched by warmer currents.
But a just-returned voyage to the frozen region found the waters
around the glacier were warmer than expected and likely melting
the ice from below.
"We knew that the glacier was thinning from the satellite data,
and we didn't know why," the voyage's chief scientist Steve
Rintoul told AFP. He said that up until recently the East Antarctica ice sheet had
been thought surrounded by cold waters and therefore very
stable and unlikely to change much.
But the voyage found that waters around the glacier were some 1.5 degrees Celsius warmer than other areas visited on
the same trip during the southern hemisphere summer.
"We made it to the front of the glacier and we measured temperatures that were warm enough to drive significant melt,"
Rintoul said.
"And so the fact that warm water can reach this glacier is a sign that East Antarctica is potentially more vulnerable to
changes in the ocean driven by climate change than we used to think."
Previous expeditions had been unable to get close to the glacier due to heavy ice, but Rintoul said the weather had held
for the Aurora Australis icebreaker and a team of scientists and technicians from the Australian Antarctic Division and
other bodies.
Rintoul said the glacier was not about to melt entirely overnight and cause a six-metre rise in sea levels, but the
research was important as scientists try to predict how changes in ocean temperatures will impact on ice sheets.
"This study is a step towards better understanding of exactly which parts of the ice sheets are vulnerable to ocean
warming and that is the sort of information that we can then use to improve our predictions of future sea level rises," he
said.
"East Antarctica is not as protected from change as we use to think," he said.
The melt rate of glaciers in the fastest-melting part of Antarctica has tripled over the past decade, analysis of the past 21
years showed, according to research published last month.
SYDNEY - The largest glacier in East Antarctica, containing ice equivalent to a six-metre (20-foot) risein global sea levels, is melting due to warm ocean water, Australian scientists said on Monday.The 120-kilometre (74.4 mile) long TottenGlacier, which is more than 30 kilometres wide, had been thoughtto be in an area untouched by warmer currents.But a just-returned voyage to the frozen region found the watersaround the glacier were warmer than expected and likely meltingthe ice from below."We knew that the glacier was thinning from the satellite data,and we didn't know why," the voyage's chief scientist SteveRintoul told AFP. He said that up until recently the East Antarctica ice sheet hadbeen thought surrounded by cold waters and therefore verystable and unlikely to change much.But the voyage found that waters around the glacier were some 1.5 degrees Celsius warmer than other areas visited onthe same trip during the southern hemisphere summer."We made it to the front of the glacier and we measured temperatures that were warm enough to drive significant melt,"Rintoul said."And so the fact that warm water can reach this glacier is a sign that East Antarctica is potentially more vulnerable tochanges in the ocean driven by climate change than we used to think."Previous expeditions had been unable to get close to the glacier due to heavy ice, but Rintoul said the weather had heldfor the Aurora Australis icebreaker and a team of scientists and technicians from the Australian Antarctic Division andother bodies.Rintoul said the glacier was not about to melt entirely overnight and cause a six-metre rise in sea levels, but theresearch was important as scientists try to predict how changes in ocean temperatures will impact on ice sheets."This study is a step towards better understanding of exactly which parts of the ice sheets are vulnerable to oceanwarming and that is the sort of information that we can then use to improve our predictions of future sea level rises," hesaid."East Antarctica is not as protected from change as we use to think," he said.The melt rate of glaciers in the fastest-melting part of Antarctica has tripled over the past decade, analysis of the past 21years showed, according to research published last month.
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