soc.culture.china

The UK work is discovering just how fast the ice is moving

UK scientists working in Antarctica have found some of the clearest
evidence yet of instabilities in the ice of part of West Antarctica.

If the trend continues, they say, it could lead to a significant rise
in global sea level.

The new evidence comes from a group of glaciers covering an area the
size of Texas, in a remote and seldom visited part of West Antarctica.

The "rivers of ice" have surged sharply in speed towards the ocean.

David Vaughan, of the British Antarctic Survey, explained: "It has
been called the weak underbelly of the West Antarctic Ice Sheet, and
the reason for that is that this is the area where the bed beneath the
ice sheet dips down steepest towards the interior.

"If there is a feedback mechanism to make the ice sheet unstable, it
will be most unstable in this region."

There is good reason to be concerned.

Satellite measurements have shown that three huge glaciers here have
been speeding up for more than a decade.

Julian Scott has just returned from there. He told the BBC: "This is a
very important glacier; it's putting more ice into the sea than any
other glacier in Antarctica.

"It's a couple of kilometres thick, and it's moving at per
year, so it's putting a lot of ice into the ocean."


At times, the temperature got down to minus 30C and strong winds made
work impossible.


The reason does not seem to be warming in the surrounding air.

Much higher up the course of the glacier there is evidence of a
volcano that erupted through the ice about 2,000 years ago and the
whole region could be volcanically active, releasing geothermal heat
to melt the base of the ice and help its slide towards the sea.

Julian Scott (BBC)

Geothermal activity may be playing its part, says Julian Scott

David Vaughan believes that the risk of a major collapse of this
section of the West Antarctic ice sheet should be taken seriously.

"There has been the expectation that this could be a vulnerable area,"
he said.

"Now we have the data to show that this is the area that is changing.
So the two things coinciding are actually quite worrying."

Antarctic glaciers surge to ocean
By Martin Redfern
Rothera Research Station, Antarctica

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