- The Washington Times - Monday, August 12, 2002

LONDON The "Asian Brown Cloud," a two-mile-thick blanket of pollution over South Asia, may be causing the premature deaths of a half-million people in India each year, deadly flooding in some areas and drought in others, according to the biggest scientific study of the phenomenon.

The grimy cocktail of ash, soot, acids and other damaging airborne particles is as much the result of low-tech polluters, such as wood- and dung-burning stoves, cooking fires and forest clearing, as it is of dirty industries, the U.N.-sponsored study found.

"When you think about air pollution, many people think of industry and fossil fuels as the only causes," co-author Paul Crutzen, a scientist at the Max Planck Institute for Chemistry in Mainz, Germany, told a news conference in London.

Often ignored, he said, was "biomass burning," including forest fires and the burning of vegetation to clear land or to warm the homes of poor people.

More than 200 scientists contributed to the study, overseen by the United Nations Environment Program in preparation for the World Summit on Sustainable Development opening Aug. 26 in Johannesburg. They used data from ships, planes and satellites to study Asia's haze from 1995 to 2000.

The scientists say more research is needed but that some trends are clear. Respiratory illness appears to be increasing with the pollution in densely populated South Asia, with one study suggesting it may be responsible for 500,000 premature deaths annually in India.

The dense cloud of pollution also caused by auto emissions, factories and waste incineration cuts by 10 percent to 15 percent the amount of sunlight reaching the ground and the oceans, cooling the land and water while heating the atmosphere.

That phenomenon appears to have altered the region's monsoon rains, increasing rainfall and flooding in Bangladesh, Nepal and northeastern India, while cutting back needed seasonal precipitation in Pakistan and northwestern India.

Floods, drought, sunlight reduction and acid rain all can hurt agricultural yields, with the report indicating that the pollution may be cutting India's winter rice harvest by as much as 10 percent.

Veerabhadran Ramanathan of the Scripps Institution of Oceanography in La Jolla, Calif., one of the authors of the report, said the extent of the sunlight loss was "a major surprise."

Scientists say it's too early to draw definite conclusions about the effect of the cloud and of similar hazes over East Asia, South America and Africa.

"We need much more basic scientific data to be able to establish what are the consequences for human health and the environment," said Mr. Crutzen, co-winner of the 1995 Nobel chemistry prize for his work on the ozone layer.

But they warn the effect could be global since prevailing winds push pollution clouds halfway around the world in just a week.

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