http://story.news.yahoo.com/news?tmpl=story&u=/afp/20031024/
ts_alt_afp/us_environment_climate_031024133656
Fri, Oct 24, 2003
Arctic ice cap melting at worrying rate:
NASA
[ Photograph
from original article... ]
CAPTION:
"This undated NASA composite image shows a fully dark (city
lights)
full disk image centered on the North Pole. The image was made
from
a combination of AVHRR, NDVI, Seawifs, MODIS, NCEP, DMSP and Sky2000
catalog data." (AFP-NASA/File)
WASHINGTON (AFP) - The polar ice cap is melting at an alarming
rate due to global warming, according to NASA scientists, with
satellite images showing the ice cap has been shrinking by
10 percent per decade over the past quarter century.
"It is happening
now. We cannot afford to wait a long period
of time for technological solutions," said David Rind of
NASA's
Goddard Institute for Space Studies in New York.
"Change is in
the air -- literally," he told a press conference
here Thursday.
By means of a special
satellite launched last year to measure
the thickness of the polar ice cap, NASA has confirmed that part
of the Arctic Ocean that remains frozen all year round shrank
at a rate of 10 percent per decade since 1980, NASA researcher
Josefino Comiso said.
"The extent of
Arctic sea ice that remains frozen all year
reached record lows in 2002 and 2003," he added.
The polar ice cap expands
in winter and contracts in spring
and summer. The part of the ice cap that never melts, even
in the warmest summers, is called the "perennial sea ice."
The oceans and land
masses surrounding the Arctic Ocean have
warmed one degree Celsius (two degrees Fahrenheit) during
the past decade, scientists said.
Researchers at the
National Aeronautics and Space Administration
are worried because global warming speeds up as the ice cap melts,
forming a vicious cycle.
"Snow and sea-ice
are highly reflective because they are white,"
Comiso said.
"Most of the sun's
energy is simply reflected back to space.
With retraction of the ice cover, that means that less of surface
is covered by this highly reflective snow and sea ice, and
so more energy has been absorbed and the climate warms."
The warming trend has
brought spectacular consequences.
US and Canadian scientists reported in September that the
largest ice shelf in the Arctic off Canada's coast has
broken up due to climate change and could endanger shipping
and drilling platforms in the Beaufort Sea.
The Ward Hunt Ice Shelf
had been in place on the north coast
of Ellesmere Island in Canada's Nunavut territory for at least
3,000 years.
"Small changes
in ice could mean big impacts on the water cycle
and ultimately the global climate," warned NASA.
The changes could alter
ocean currents, the distribution of
fish populations and precipitation averages over a wide area.
"One activity
in the north is hunting of marine animals using
sea-ice as a platform. When sea-ice retreats, it affects the
communities up there," said University of Washington oceanographer
Michael Seteele.
"The Arctic is
changing rapidly. We should be concerned in the
sense we need to simply recognize the change is here, is occurring
and we may have to adapt to it," University of Colorado researcher
Mark Serreze told reporters.
"Why the increase
in global temperature?" he asked.
"Part of this
is probably simply due to natural variability
in the climate system," he added. "But the general consensus
of the climate community is that part these changes are due
to human impact."
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