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Arctic to be 'ice-free in summer'
BBCnews.com, Oct. 15, 2009
The
Arctic Ocean could be largely ice-free and open to shipping during the
summer in as little as ten years' time, a top polar specialist has
said.
"It's
like man is taking the lid off the northern part of the planet," said
Professor Peter Wadhams, from the University of Cambridge.
Professor Wadhams has been studying the Arctic ice since the 1960s.
He was speaking in central London at the launch of the findings of the Catlin Arctic Survey.
The expedition trekked across 435km of ice earlier this year.
Led
by explorer Pen Hadow, the team's measurements found that the ice-floes
were on average 1.8m thick - typical of so-called "first year" ice
formed during the past winter and most vulnerable to melting.
The
survey route - to the north of Canada - had been expected to cross
areas of older "multi-year" ice which is thicker and more resilient.
When the ridges of ice between floes are included, the expedition found an average thickness of 4.8m.
Professor
Wadhams said: "The Catlin Arctic Survey data supports the new consensus
view - based on seasonal variation of ice extent and thickness, changes
in temperatures, winds and especially ice composition - that the Arctic
will be ice-free in summer within about 20 years, and that much of the
decrease will be happening within 10 years.
"That
means you'll be able to treat the Arctic as if it were essentially an
open sea in the summer and have transport across the Arctic Ocean."
According
to Professor Wadhams, faster shipping and easier access to oil and gas
reserves were among short-term benefits of the melting.
But
in the longer-term, losing a permanent feature of the planet risked
accelerated warming, changing patterns of circulation in the oceans and
atmosphere, and having unknown effects on ecosystems through the
acidification of waters.
Pen
Hadow and his companions Ann Daniels and Martin Hartley endured
ferocious weather - including a wind chill of minus 70 - delayed
resupply flights and starvation rations during the expedition from 1
March to 7 May.
When
I met them on the ice, as part of a BBC team that joined the pick-up
flight, all three had lost weight and were evidently tired from the
ordeal.
The
expedition had been blighted by equipment failures. A pioneering radar
system, designed to measure the ice while being dragged over the ice,
broke down within days. Another device to measure the water beneath the
ice never functioned at all.
A planet transformed
The
technical breakdowns forced the team to rely on hand-drilling through
the ice which slowed progress and meant the team's planned destination
of the North Pole had to be abandoned.
Pen
Hadow admitted that the expedition had not led to "a giant leap forward
in understanding" but had been useful as an incremental step in the
science of answering the key questions about the Arctic.
His
view was backed by Professor Wadhams who said the expedition had
provided information about the ice that was not available from
satellites and that no submarines had been available to science at that
time either.
Pen Hadow said he was shocked by the image of how "in my lifetime we're looking at changing how the planet looks from space."
He
also described how polar explorers were having to change their methods
from the days when sledges could be pulled by dogs over the ice.
"Dogs can swim but they can't tow a sledge through water which is what's needed now."
"Now
we have to wear immersion suits and swim and we need sledges that can
float. I can foresee needing sledges that are more like canoes that you
also pull over the ice."
© BBC MMIX
http://news.bbc.co.uk/2/hi/science/nature/8307272.stm
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