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The
Earth's crust in West Antarctica is rising by up to 4.1
centimeters (1.61 inches) a year, an international team wrote in
the journal Science, in a continental-scale version of a foam
mattress reforming after someone sitting on it gets up.
The rate, among the fastest ever recorded, is likely to
accelerate and could total 8 meters (26.25 feet) this century,
they said, helping to stabilize the ice and brake a rise in sea
levels that threatens coasts from Bangladesh to Florida.
"It's good news for Antarctica," lead author Valentina Barletta
of the Technical University of Denmark and Ohio State University
told Reuters of the findings, based on GPS sensors placed on
bedrock around the Amundsen Sea in West Antarctica.
Much of the West Antarctic ice sheet, which has enough ice to
raise world sea levels by more than three meters (10 feet) if it
ever all melted, rests on the seabed, pinned down by the weight
of ice above.
The fast rise of the bedrock beneath will lift ever more of the
ice onto land, reducing the risks of a breakup of the sheet
caused by warming ocean water seeping beneath the ice.
The uplift "increases the potential stability of the West
Antarctic Ice Sheet against catastrophic collapse," the
scientists wrote.
Last week, another study said that three trillion tonnes of ice
had thawed off from Antarctica since 1992, raising sea levels by
almost a centimeter - a worsening trend.
It often takes thousands of years for the Earth's crust to
reshape after a loss of ice. Parts of Scandinavia or Alaska, for
instance, are still rising since the end of the last Ice Age
removed a blanket of ice more than a kilometer thick.
A further report this month found that the West Antarctic ice
sheet expanded about 10,000 years ago, interrupting a long-term
retreat after the last Ice Age, because of a rise of the land
beneath.
But it said the process was too slow to save the ice sheet from
a possible collapse triggered by global warming.
One of the lead authors of that study, Torsten Albrecht at the
Potsdam Institute for Climate Impact Research, told Reuters on
Thursday: "The expected eight-metre (26.4-foot) uplift in 100
years in the Amundsen Sea region ... seems rather small in order
to prohibit future collapse."
(Reporting by Alister Doyle; Editing by Mark Heinrich)
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