Water found at North Pole Melting viewed as possible sign of global warming
Saturday, August 19th 2000, 12:00 am
News On 6
The thick ice that has for ages covered the Arctic Ocean at the North Pole has turned to water, recent visitors there reported Friday.
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 could be further evidence that global warming is real and already affecting climate.
Scientists say the last time the pole was definitely awash in water was more than 50 million years ago.
"It was totally unexpected," said Dr. James J. McCarthy, an oceanographer on a tourist cruise in the Arctic aboard a Russian icebreaker.
Recalling the reaction of passengers this month when they saw an iceless North Pole, Dr. McCarthy said: "There was a sense of alarm. Global warming was real, and we were seeing its effects for the first time that far north."
On a similar Arctic cruise six years ago, Dr. McCarthy recalled, the icebreaker plowed through an icecap 6 to 9 feet thick at the North Pole.
This time, ice was generally so thin that sunlight could penetrate and support concentrations of plankton growing beneath. Dr. McCarthy said the Russian captain of the icebreaker, who has made the voyage 10 times in recent years, said he had never before encountered open water at the pole.
Dr. McCarthy is director of the Museum of Comparative Zoology at Harvard University and the co-leader of a group working for the United Nations-sponsored Intergovernmental Panel on Climate Change. The panel is studying the potential environmental and economic consequences of marked climate change.
Another lecturer on the cruise, Dr. Malcolm C. McKenna, a paleontologist at the American Museum of Natural History in New York, 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 â€“ which Dr. McKenna and his wife, Priscilla, confirmed with a hand-held global positioning system navigation device â€“ 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. He instantly snapped pictures to document the phenomenon in photographs.
The Yamal had to steam six miles away to find ice thick enough for the 100 passengers to get out and say they had stood close to the North Pole. 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 25 years. That's significant, 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 said.
The Eocene was the geological period when the world's climate grew significantly warmer. About 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 recent warming trend in the northern polar region and have raised the possibility of a melting icecap.
Dr. McCarthy said that he would report the Yamal's encounter with open polar water to environmental scientists and consult other scientists to see whether new satellite remote-sensing data have detected the extent of the melting ice.