McClatchy Newspapers | Les Blumenthal | Aug. 29, 2008
Scientists fear impact of Asian pollutants on U.S. – From 500 miles in space, satellites track brown clouds of dust, soot and other toxic pollutants from China and elsewhere in Asia as they stream across the Pacific and take dead aim at the western U.S.
A fleet of tiny, specially equipped unmanned aerial vehicles, launched from an island in the East China Sea 700 or so miles downwind of Beijing , are flying through the projected paths of the pollution taking chemical samples and recording temperatures, humidity levels and sunlight intensity in the clouds of smog.
On the summit of 9,000-foot Mt. Bachelor in central Oregon and near sea level at Cheeka Peak on Washington state’s Olympic Peninsula , monitors track the pollution as it arrives in America.
By some estimates more than 10 billion pounds of airborne pollutants from Asia — ranging from soot to mercury to carbon dioxide to ozone — reach the U.S. annually. The problem is only expected to worsen: Some Chinese officials have warned that pollution in their country could quadruple in the next 15 years.
While some scientists are less certain, others say the Asian pollution could destabilize weather patterns across the North Pacific, mask the effects of global warming, reduce rainfall in the American West and compromise efforts to meet air-pollution standards.
” East Asia pollution aerosols could impose far reaching environmental impacts at continental, hemispheric and global scales because of long-range transport,” according to a report earlier this year in the Journal of Geophysical Research . The report said that a “warm conveyor belt” lifts the pollutants into the upper troposphere — the lowest layer of Earth’s atmosphere — over Asia , where winds can bring it to the U.S. in a week or less.
The National Academies of Science, at the request of the Environmental Protection Agency , NASA , the National Oceanic and Atmospheric Administration and in consultation with the State Department , has assembled a panel to examine the problem and its impact. Its report is due next summer.
“Everyone realizes this is an issue of growing importance,” said Laurie Geller of the National Academies of Science. “This is very challenging science with lots of complexities and a lot of uncertainties.”
Though the problem of Asian air pollution has been known for years, no one has a handle on how much is blown in and what it includes. Scientists say Washington state and Oregon might be feeling the brunt of the effects.
“This pollution is distributed on average equally from northern California to British Columbia ,” said Dan Jaffe , a professor of environmental science at the University of Washington’s Bothell campus. “Anyone who has gone out to measure it has found something.”
Particulates such as dust and soot, along with heavy metals, pesticides, PCBs, mercury, ozone, carbon dioxide, nitrogen dioxide and sulfur dioxide have all been found. Jaffe said the pollutants can’t be tracked to a single source such as a particular coal-burning plant, but their “chemical fingerprints” can point to a specific country.
. . . more