Nature
magazine suggests in a recent report, that Greenland's ice sheet could disappear
within the next 1,000 years if global warming continues at its present
rate.
Researchers from the University of Reading, UK, including Jonathan Gregory
revealed that their studies forecast an 8 degrees C increase in Greenland's
temperature by 2350, and believe that if the ice cap melts, global average
sea level will rise by about 7m (23ft).
They say that even if global warming
was halted the rise could be irreversible.
What does it all mean.
They found that over the next 350 years global warming
was likely to pass the critical threshold in 34 out of 35 model calculations,
and have estimated that Greenland could pass a level of warming beyond
which the ice sheet could not be sustained unless very significant reductions
were made in emissions of greenhouse gases like Co2.
Thay think that
it's quite possible that Greenland is already making a slight contribution
to global sea levels.
"Without the ice sheet, the climate of Greenland
would be greatly altered," says Dr Gregory.
Greenland's average temperature only needs to increase by 3C to melt its
ice sheet, but some of the modelling studies forecast a much higher rise
by the year 2350.
"Unlike the ice on the Arctic Ocean, much of which
melts and reforms each year, the Greenland ice sheet might not re-grow
even if the global climate were returned to pre-industrial conditions," he
says.
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Some
new evidence may suggest the ice sheet has already to started to melt.
"It's quite possible that Greenland is already
making a slight contribution to global sea levels," says Dr Gregory.
A
broad consensus of mainstream scientific opinion holds that human-produced
greenhouse gases, such as carbon dioxide (CO2), are driving an unnatural
rise in global temperatures.
Before industrialisation, the atmosphere contained
280 parts per million (ppm) of CO2. At present, it stands at 370 ppm.
The
only international agreement on cutting greenhouse gases is the UN's
Kyoto Protocol, which requires industrial countries to make a small cut
in global emissions by a timeframe of 2008-12.
But the pact seems to be going nowhere at the
moment, and still needs to be ratified by Russia to take effect and has
been abandoned by the United States, the world's biggest CO2 contributor.
If the ice of the world stands a chance of surviving
into the future, therefore keeping see levels at bay so as to reduce flooding,
then we need to realy start acting now.
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