*NEWS* ANTARCTIC GLACIERS SHRINKING

[Anonymous]

Study Shows Antarctic Glaciers Shrinking

LONDON(April 05)-The
first comprehensive survey of glaciers on the Antarctic peninsula has shown that
the rivers of ice are shrinking, mostly because of warming of the local
climate.

It is unclear, however, whether the increased temperature
causing the shrinkage is a natural regional effect or a result of
human-influenced global warming, said the scientists who conducted the study,
published this week in the journal Science.

Researchers from the British Antarctic Survey and the U.S.
Geological Survey analyzed more than 2,000 aerial photographs dating from 1940
and over 100 satellite images from the 1960s onwards.

They calculated that 87 percent of the 244 glaciers going
out to sea from the peninsula have retreated over the last 50 years and that the
pace of shrinkage has accelerated over the last decade. Until now, scientists
were uncertain whether the glaciers were growing or melting.

”Fifty years ago, most of the glaciers we look at were
slowly growing in length but since then this pattern has reversed. In the last
five years the majority were actually shrinking rapidly,” said the study’s
leader, Alison Cook of the British Antarctic Survey. ”However, 32 glaciers go
against the trend and are showing minor advance. Had we not studied such a large
number of glaciers we may have missed the overall pattern.”

The Antarctic peninsula is a small segment of the Antarctic
continent, located at the South Pole, and the behavior of the ice on the
peninsula is not necessarily a reflection of what’s going on elsewhere in
Antarctica, said another of the investigators, David Vaughan of the British
Antarctic Survey.

Temperatures seem to be much warmer there than on the rest
of the continent.

Evidence from the main Antarctic ice sheet is mixed, with
some areas of the continent showing shrinkage and others showing thickening.

Ice shrinkage has also been documented in Alaska and the
North Pole.

Scientists worry about the melting of the ice sheets
because the extra water may increase sea levels, which in turn could mean more
flooding damage to coastal areas during storms.

Sea levels have risen by 10 centimeters to 20 centimeters
over the last 100 years and experts predict it could rise by a meter over the
next 100 years. However, the study was not able to tell whether the shrinkage is
having a meaningful impact on sea levels.

It is also unclear whether changes in the larger ice sheet
in Antarctica are contributing to sea level rise, Vaughan said.

”This is another piece in the jigsaw that tells us how
climate change is affecting the planet. It may not be a significant piece, but
there’s a million-piece jigsaw out there to be filled in … and this is one
piece in it,” Vaughan said.

[Author]

April 23, 2005 at 11:04 AM