From: Rohit Khare (Rohit@KnowNow.com)
Date: Sat Aug 19 2000 - 15:34:20 PDT
[wow... you really don't get to write ledes like this too often. Five
words, and completely unbelievable, and completely true...! RK]
Ages-Old Polar Icecap Is Melting, Scientists Find
By JOHN NOBLE WILFORD
The 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.
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