Watching the ice caps melt

Scientists say Arctic warming comes with plusses and minuses

Posted: Wednesday, June 21, 2000

FAIRBANKS -- Geophysicist Josefino Comiso looks at the Arctic ice cap from above. Colleague Peter Wadhams makes his observations from below.

When the two put their science together, they confirm what Eskimo whaling captain Eugene Brower has seen from shore for most of his adult life: The ice is disappearing, and the vanishing act is accelerating.

``There's been a lot of change,'' said Brower, president of the Barrow Whaling Captains Association. ``Last year the ice went over the horizon and stayed over the horizon all summer. We would have to go over 20 or 30 miles just to hunt seals.''

Comiso, Wadhams and more than 100 of their scientific brethren are in Fairbanks this week to discuss the health of the Arctic and Antarctic ice caps during the International Symposium on Sea Ice and Its Interactions with the Ocean, Atmosphere and Biosphere. The conference is being held at the University of Alaska Fairbanks.

The disappearance of the northern ice cap and the reasons why will be one of the primary topics.

``I'm seeing the thinning,'' said Wadhams, ``and Joey (Comiso) is seeing the shrinking.''

Wadhams studies at the Scott Polar Research Center at Cambridge University in England. His specialty is analyzing data taken from beneath the ice cap by submarines.

Comiso works for NASA's Goddard Space Flight Center at Greenbelt, Md. He studies ice cap data gathered by satellites.

``Those guys are two of the movers and shakers,'' said Martin Jeffries, the UAF scientist who headed the local organizing committee for the symposium. ``These are two of the leading sea-ice geophysicists.''

Several reasons are being cited for why the ice cap is beginning to recede and thin. Along with the planet's natural warming cycle, it's generally agreed that humans are polluting the atmosphere with carbon-dioxide and chlorofluorocarbons that are causing a greenhouse effect.

It also appears the world's 10-year ocean cycles are adding to the mix. Warm water at the northern reaches of the Gulf Stream is making its way under the polar cap. That appears to be speeding melting. Add wind and other natural climate factors and the united assault is having a pronounced and visible effect.

``The last three years there's been a dramatic change in open water in the Beaufort Sea,'' Comiso said. ``There's a big chunk of ice disappearing from the area. The ice has been shrinking 2 to 3 percent every year for the last 20 years.''

On average, the earth is warming at 0.5 degrees Celsius a century, Comiso said. In the Arctic, the rise has been more dramatic at 0.7 degrees. It doesn't sound like much, but it all adds up.

The change has been dramatic in the Beaufort. There were 300,000 square kilometers of open water in 1996. That rose to 700,000 in 1997 and 970,000 in 1998.

``If that continues, it will become a recreational area,'' Comiso said of Alaska's north coast.

The scientists recited a number of changes likely to occur in Alaska because of the warming trend.

Imagine, Wadhams said, a summertime passage along the entire Arctic coastline of North America. The Northeast Passage already is opening and the Northwest Passage seems to be headed in the same direction.

Oil companies would benefit from the summertime trade route and also find it easier to explore the northern ocean because icebreakers easily can deal with single-season ice rather than the multiyear buildups that once were the norm.

It also would mean changes in the migration of whales and other marine mammals that make up so much of the Inuit diet, and life could be made more difficult by the presence of more storms, clouds and snow.

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