OT.....this is serious and alarming news......Ages-Old Polar Icecap Is Melting,
Scientists Find
By JOHN NOBLE WILFORD
he North Pole is melting.
The thick ice that has for ages covered the
Arctic Ocean at the pole has turned to
water, recent visitors there reported
yesterday. At least for the time being, an
ice-free patch of ocean about a mile wide
has opened at the very top of the world,
something that has presumably never before
been seen by humans and is more evidence
that global warming may be real and already
affecting climate.
The last time scientists can be certain the pole was awash in water was
more than 50 million years ago.
"It was totally unexpected," said Dr. James J. McCarthy, an
oceanographer, director of the Museum of Comparative Zoology at
Harvard University and the co-leader of a group working for the
Intergovernmental Panel on Climate Change, which is sponsored by the
United Nations. The panel is studying the potential environmental and
economic consequences of marked climate change.
Dr. McCarthy was a lecturer on a tourist cruise in the Arctic aboard a
Russian icebreaker earlier this month. On a similar cruise six years ago,
he recalled, the icebreaker plowed through an icecap six to nine feet
thick at the North Pole.
This time, ice was generally so thin that sunlight could penetrate and
support concentrations of plankton growing under the ice. Dr. McCarthy
said the icebreaker's Russian captain, who has made the voyage 10 times
in recent years, said he had never before encountered open water at the
pole.
Another lecturer, Dr. Malcolm C. McKenna, a paleontologist at the
American Museum of Natural History, said the ship, the Yamal,
crunched through miles of unusually thin ice and intermittent open water
on the approach from Spitsbergen, Norway, to the pole. When the ship
reached the pole -- which Dr. McKenna and his wife, Priscilla,
confirmed with a hand-held Global Positioning System Priscilla,
confirmed with a hand-held Global Positioning System navigation device
-- water lapped its bow.
"I don't know if anybody in history ever got to 90 degrees north to be
greeted by water, not ice," Dr. McKenna said in an interview. He
instantly snapped pictures to document the phenomenon in photographs.
The Yamal eventually had to steam six miles away to find ice thick
enough for the 100 passengers to get out and be able to say they had
stood on the North Pole, or close to it. They saw ivory gulls flying
overhead, the first time ornithologists said they had ever been sighted at
the pole.
Over the last century, the average surface temperature of the globe has
risen by about 1 degree Fahrenheit, and the rate of warming has
accelerated in the last quarter century. (That's a significant amount,
considering that the world is only 5 to 9 degrees warmer now than it was
in the last ice age, 18,000 to 20,000 years ago.) Scientists and policy
makers are still arguing about whether this is a natural fluctuation or an
effect of industrial society's releasing heat-trapping gasses into the
atmosphere.
"Some folks who pooh-pooh global warming might wake up if shown
that even the pole is beginning to melt at least sometimes, as in the
Eocene," Dr. McKenna added.
The Eocene was the geological period when the world's climate grew
significantly warmer. Around 55 million years ago, according to
sedimentary and fossil evidence, tropical vegetation spread inside the
Arctic and Antarctic circles. Water and jungles dominated the polar
environments, and in the generally warm world, mammals for the first
time grew in number, size and diversity.
Previous studies of satellite and submarine observations have seemed to
establish a warming trend in the northern polar region and raise the
possibility of a melting icecap.
Scientists at the Goddard Space Science Institute, a NASA research
center in Manhattan, compared data from submarines in the 1950's and
60's with 90's observations, demonstrating that the ice cover over the
entire Arctic basin has thinned by 45 percent. Satellite images have
revealed that the extent of ice coverage has significantly shrunk in recent
years.
Dr. McCarthy said he would report the encounter with open polar water
to environmental scientists and consult other scientists to see if new
satellite remote-sensing data have detected the extent of the melting.
Recalling the reaction of passengers when they saw an iceless North
Pole, he said: "There was a sense of alarm. Global warming was real, and
we were seeing its effects for the first time that far north."
In their models of climate patterns, scientists have long suggested that the
northern polar region would be affected earlier and more seriously than
the southern region.
They said the greater expanse of land in the northern hemisphere should
respond more rapidly to temperature change, presumably leading to
marked climate change. |
