| NY ALESUND, Norway
NY ALESUND, Norway A thaw of Antarctic ice is
outpacing predictions by the U.N. climate panel and could in
the worst case drive up world sea levels by 2 meters (6 ft) by
2100, a leading expert said on Wednesday.
Millions of people, from Bangladesh to Florida and some
Pacific island states, live less than a meter above sea level.
Most of the world's major cities, from Shanghai to Buenos
Aires, are by the sea.
Chris Rapley, the outgoing head of the British Antarctic
Survey, said there were worrying signs of accelerating flows of
ice towards the ocean from both Antarctica and Greenland with
little sign of more snow falling inland to compensate.
"The ice is moving faster both in Greenland and in the
Antarctic than the glaciologists had believed would happen,"
Rapley told Reuters during a climate seminar in Ny Alesund on a
Norwegian Arctic island 1,200 km from the North Pole.
"I think the realistic view is that we will be nearer a
meter than the 40 cm" in sea level rise by 2100, Raply said.
The U.N. climate panel in February gave a likely range of 18 to
59 cm this century, for an average around 40 cm.
Asked at the seminar what the upper limit for the rise
might be at a probability of one percent or less, he said: "At
this extremely unlikely level the maximum would be two meters."
Skeptics often dismiss such low probabilities as
scaremongering. But many scientists note that people take
precautions such as to insure their homes against far lower
risks, such as fire.
The U.N. panel said that rising temperatures due to more
and more greenhouse gases from human activities led by use of
fossil fuels were melting ice.
Antarctica stores enough ice to raise ocean levels by about
57 meters if it ever all melted. Greenland has about 7 meters,
according to U.N. data.
All other glaciers on land, from the Norwegian Arctic to
the Himalayas, are tiny by comparison and contain only enough
ice combined to raise sea levels by about 15-37 cm.
Glaciers around Ny Alesund, which calls itself the world's
most northerly settlement, are also retreating fast.
The U.N.'s Intergovernmental Panel on Climate Change (IPCC)
in February hedged its forecasts by saying that "larger values
cannot be excluded" but said there was too little understanding
of how ice sheets react if water seeps beneath them and
lubricates their slide.
Rapley said there were worrying signs of an accelerating
thaw both in West Antarctica, where much of the ice sits on
rocks that are below sea level, and on the Cook and Totten
glaciers on the fringe of the far bigger ice mass to the East.
"The East Antarctic ice sheet is always dismissed as the
big bit which sits on rock above sea level and so is much more
stable. But the radar altimeters show significant discharge
going on," he said.