Antarctic thaw is twice as bad as anyone thought
New research reveals that original climate estimates were based on
faulty data
Temperatures in the western part of Antarctica are rising almost
twice as fast as previously believed, adding to fears that continued
thaws are causing sea levels to rise, according to comprehensive
research.
In a discovery that raises new concerns about the effects of climate
change on the South Pole, the average annual temperature in the region
has risen by 2.4C since the 1950s, three times faster than the average
around the world.
The unexpected jump was discovered after David Bromwich, Professor of
Geography at Ohio State University, led a research team to the
previously uninhabited Byrd Station research centre 700 miles from the
South Pole in the heart of West Antarctica.
Their research claims that original estimates, which were half those
revealed this week, were based on faulty data. They found that nearly
one third of temperature observations had been missing for the past 60
years due to regular power outages and limited resources. Professor
Bromwich and the study's co-author, Andrew Monaghan, went back over the
outpost's findings since it opened in 1957, reassessing previous
predictions and modelling atmospheric changes.
The link between rising temperate and rising sea levels is based on
the principle of displacement. In this instance, the 2.4C rise has added
to worries that huge blocks of ice could slide into the ocean, causing
the surrounding seas to rise to accommodate new icebergs.
Several ice shelves - thick ice blocks attached to the land at one
end - have already collapsed around the Antarctic Peninsula, an area
just to the north of the Byrd Research Centre. Once these shelves break
up, glaciers trapped behind them can slide faster into the sea, raising
water levels. Professor Bromwich said: "Our record suggests that
continued summer warming in West Antarctica could upset the surface mass
balance of the ice sheet, so that the region could make an even bigger
contribution to sea level rise than it already does."
The region contains enough ice to raise sea levels by at least 3.3m
(10.8ft) if it all melted, a process that would likely take centuries.
But, according to these findings, it is now the second largest
contributor to global rises with 0.3mm per year to Greenland's 0.7mm.
-The Independent
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