faster than was earlier projected and could raise global sea levels by
as much as 1.6 meters by 2100,says a new study.
The study released on Tuesday bythe Arctic Monitoring and Assessment
Program )AMAP( said there is a "need for greater urgency" in fighting
global warming as record temperatures have led to the increased rate
of melting.
The AMAP report said the corresponding rise in water levelswill
directly threaten low-lying coastal areas such as Florida and
Bangladesh, but would also affect islands and cities from London to
Shanghai. The report says it will also increase the cost of rebuilding
tsunami barriers in Japan.
"The past six years )until 2010( have been the warmest period ever
recorded in the Arctic," said the report.
"In the future, global sea level is projected to rise by 0.9 meters to
1.6 meters by 2100 and the loss of ice from Arctic glaciers, ice caps
and the Greenland ice sheet will make a substantial contribution," it
added.
The rises had been projected from levels recorded in 1990.
Dramatic rise from projections
In its last major study in 2007, the United Nations' Intergovernmental
Panel on Climate Change )IPCC( said that sea levels were likely to
rise by only between 18 and 59 centimeters by 2100, though those
numbers did not include any possible acceleration due to athaw in the
polar regions.
The new AMAP assessment says that Greenland lost ice in the 2004-2009
period four times faster than it did between 1995-2000.
The AMAP is the scientific arm of the eight-nation Arctic Council.
Foreign ministers from council nations - the United States, Russia,
Canada, Sweden, Finland, Denmark, Norway and Iceland -- are due to
meet in Greenland on May 12, and will discuss the AMAPreport's
findings.
The report is expected to be discussed by about 400 international
scientists at a conference this week in Copenhagen, Denmark.
"The increase in annual average temperature since 1980 has been twice
as high over the Arctic as it has been over the rest of the world,"
the report said. Temperatures were higher than at any time in the past
2,000 years."
In its report, the IPCC had said that it was at least 90 per cent
probable that emissions of greenhouse gases by human beings, including
the burning of fossil fuels, were to blame for most of the warming in
recent decades.
"It is worrying that the most recent science points to much higher sea
level rise than we havebeen expecting until now," Connie Hedegaard,
the European Climate Commissioner, told the Reuters news agency.
"The study is yet another reminder of how pressing it has become to
tackle climate change,although this urgency is not always evident
neither in the public debate nor from the pace in the international
negotiations," she said.
UN talks on a global accord to combat climate change have been making
slow progress, and the organization says national promises to limit
greenhouse gasemissions are now insufficient to avoid possibly
catastrophic consequences of global temperature rises.
Arctic could be ice-free
The AMAP study, which drew on the work of hundreds of experts, said
that there were signs warming in the Arctic was accelerating, and that
the Arctic Ocean could be nearly free of ice in the summers within 30
or 40 years. This, too, was higher than projected by the IPCC.
While the thaw would make the Arctic more accessible for oil
exploration, mining and shipping, it would also disrupt the
livelihoods of people who livethere, as well as threaten the survival
of creatures such as polarbears.
"There is evidence that two components of the Arctic cryosphere - snow
and sea ice - are interacting with the climate system to accelerate
warming," the report said.
The IPCC estimate was based largely on the expansion of oceanwaters
from warming and the runoff from melting land glaciers elsewhere in
the world.
The AMAP report says that Arctic temperatures in the past six years
have been at their highest levels since measurements beganin 1880, and
the rises were being fed by "feedback" mechanisms in the far north.
One such mechanism involves theocean absorbing more heat as a result
of not being covered by ice,as ice reflects solar energy. While the
effect had been predicted by scientists earlier, the AMAP reportsays
that "clear evidence for it has only been observed in the past five
years".
Temperature rises expected
It projected that average fall and winter temperatures in the
Arcticwill climb by roughly 2.8 to 6.1 degrees Celsius by 2080, even
if greenhouse gas emissions are lower than in the past decade.
"The observed changes in sea ice on the Arctic Ocean, in the mass of
the Greenland ice sheet and Arctic ice caps and glaciers over the past
10 years are dramatic and represent an obvious departure from the
long-term patterns," AMAP said.
"The changes that are emerging in the Arctic are very strong, dramatic
even," said Mark Serreze, director of the US National Snow and Ice
Data Center in Boulder, Colorado, and acontributor to the report.
"But this is not entirely a surprise. We have known for decades that,
as climate change takes hold, it is the Arctic where you are going to
see it first, and where it is going to be pronounced," he said by
phone.
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