Thursday, September 3, 2009

Expedition finds Arctic melting fast

By ABC News Online Environment reporter Sarah Clarke

4 September 2009

With less than 100 days until the United Nations climate talks in Copenhagen, a group of scientists has embarked on a journey to see the state of the Arctic melt at first hand.
Their accounts so far tell of rapidly melting glaciers that are not only shrinking from warmer atmospheric temperatures, but are collapsing underneath from the action of higher sea levels.
It has been more than two months since some crew members on board the Greenpeace ship Arctic Sunrise have set foot on soil.
The scientists travelling on this expedition have braved huge swells and wild weather to venture out on the ice.
They have set up a floating research station and are travelling to remote parts of the Greenland coast only accessible by helicopter.
Gordon Hamilton, a glaciologist from the University of Maine, did the same trip in 2005.
"The major change is that the glaciers haven't really returned to normal, they've continued to flow at extremely fast speeds," he said.
"Maybe not quite as fast as they were in 2005, but a lot of glaciologists would have thought that it was just a very short-lived event, and that after a year or two these glaciers would return to normal.
"It's very surprising that after four years we still see these glaciers moving along in an extremely fast speed and have not returned to normal."
But it's not just the Arctic temperatures that are warming more quickly. So are the ocean waters.
By sending oceanic probes down to 1,000 metres, scientists can compare climate records to reveal how the temperatures have changed, one probe recorded 2 degrees Celsius at 60 metres, in the middle of winter.
Dr Hamilton says the warmer currents are creating a double whammy for the already diminishing glaciers and accelerating the speed at which they melt.
"Of course if the ocean is warming up, or if the ocean currents are changing and are bringing more heat into these fjords, then you get a lot of rapid melting, not on the surface of the glacier, but underlying - so submarine melting," he said.
"It turns out that submarine melting is far more effective at thinning these glaciers than surface melting, so that's a very rapid way of destabilising large parts of the Greenland ice sheet."
The findings gathered on this journey will be used by organisations like Greenpeace to call on governments globally to make deep cuts in the planet's emissions.
Photographer and campaigner Dave Walsh, who is on board the Arctic Sunrise, says the United Nations climate talks in Copenhagen have an urgent responsibility to deliver.
"I think the main message here is that ice melting in the Arctic has a huge influence on what happens elsewhere in the world," he said.
"If we've got more fresh water coming in off the Greenland ice sheet into the oceans, it's going to contribute to sea level rise."
"It's imperative that we pull back on our emissions to curb climate change so in Copenhagen we're asking the governments there, of developed countries, to make a 40 per cent cut in emissions."

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