- Record amounts of the Arctic ocean failed
to freeze during the recent winter, new figures show, spelling disaster
for wildlife and strengthening concerns that the region is locked into
a destructive cycle of irreversible climate change.
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- Satellite measurements show the area
covered by Arctic winter sea ice reached an all-time low in March, down
some 300,000 square kilometres on last year -an area bigger than the UK.
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- Scientists say the decline highlights
an alarming new trend, with recovery of the ice in winter no longer sufficient
to compensate for increased melting in the summer. If the cycle continues,
the Arctic ocean could lose all of its ice much earlier than expected,
possibly by 2030.
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- Walt Meier, a researcher at the US National
Snow and Ice Data Centre in Colorado, which collected the figures, said:
"It's a pretty stark drop. In the winter the ice tends to be pretty
stable, so the last three years, with this steady decline, really stick
out."
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- Experts are worried because a long-term
slow decline of ice around the north pole seems to have sharply accelerated
since 2003, raising fears that the region may have passed one of the "tipping
points" in global warming. In this scenario, warmer weather melts
ice and drives temperatures higher because the dark water beneath absorbs
more of the sun's radiation. This could make global warming quickly run
out of control.
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- Dr. Meier said there was "a good
chance" the Arctic tipping point has been reached. "People have
tried to think of ways we could get back to where we were. We keep going
further and further into the hole, and it's getting
- harder and harder to get out of it."
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- The Arctic is rapidly becoming the clearest
demonstration of the effects of mankind's impact on the global climate.
The temperature is rising twice as fast as the rest of the planet and the
region is expected to warm by a further 4C-7C by 2100. The summer and winter
ice levels are the lowest since satellite monitoring began in 1979, and
almost certainly the lowest since local people began keeping records around
1900.
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- The pace of decline since 2003, if continued,
would see the Arctic totally ice-free in summer within 30 years - though
few scientists would stake their reputations on a long-term trend drawn
from only three years.
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- Experts at the US Naval Postgraduate
School in California think the situation could be even worse. They are
about to publish the results of computer simulations that show the current
rate of melting, combined with increased access for warmer Pacific water,
could make the summertime Arctic ice-free within a decade. Dr. Meier said:
"For 800,000 to a million years, at least some of the Arctic has been
covered by ice throughout the year. That's an indication that, if we are
heading for an ice-free Arctic, it's a really dramatic change and something
that is unprecedented almost within the entire record of human species."
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- The winter ice has declined all around
the region - bad news for polar bears, which spend summer on land before
returning to the ice in spring to catch food.
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