Air More Polluted Than New Jersey’s : Layer of Soot Over Arctic May Be Warming Icecap

A blanket of soot may be raising temperatures around the North Pole by absorbing sunlight as well as light reflected from the icecap below, government scientists reported Wednesday.

“One pollution plume we encountered on a flight over the icecap off Barrow, Alaska, last March was the equivalent of five or six large power plants putting all their effluents in a single plume,” said Dr. Russell Schnell of the National Oceanic and Atmospheric Administration.

That layer of pollution “was about 100 miles wide and 1,000 feet deep, and when we first flew into it, we thought we had flown into . . . a volcanic eruption. We didn’t believe the instruments on the aircraft,” Schnell said.

The agency based its report on results of a five-nation study of the haze that has been observed over the Arctic region in the last three decades.

The layer has been reported to be as thick as 18,000 feet, and scientists have expressed concern that it will warm the Arctic climate, although they remain unsure of the exact effects.

There have been reports of reduced pack ice volume in the Arctic in recent years, although direct evidence has not tied this to the air pollution.

The average surface temperature of the Earth has risen slightly in recent years, probably as a result of the so-called greenhouse effect, by which the increasingly polluted atmosphere absorbs and holds in more heat from the sun.

The Arctic pollution probably comes from industrial and chemical operations in Eastern Europe and Asia, the agency said. Examinations of air flow and a chemical analysis of the pollution indicated that some of the soot had traveled as far as 4,000 miles, Schnell said.

Another participant in the study, Tony Hansen of the University of California’s Lawrence Berkeley Laboratory, said that at times, the Arctic pollution exceeded that measured over the coast of New Jersey.

Hansen said that on one test flight, carbon soot in the Arctic region was measured at 700 nanograms per cubic meter, while the highest concentration found in the New Jersey studies last January was 500 nanograms per cubic meter. (A nanogram is about one-billionth the weight of a paper clip. A cubic meter is a little more than a cubic yard of air.)

The same agency research aircraft and instruments were used in both studies.