Atmospheric scientists have detected a previously unknown Asian import smuggling its way into the United States. Smoggy air, rich in ozone pollution and other contaminants, sailed clear across the Pacific and then drifted over northwestern states in the spring of 1999.
On April 9, sensors on board an airplane flying off the coast of Washington detected enhanced ozone concentrations between 3,000 and 6,000 meters above sea level. At its worst, the ozone reached 85 parts per billion, reported Daniel Jaffe of the University of Washington at Bothell and his colleagues last month in San Francisco at a meeting of the American Geophysical Union.
A triplet of oxygen atoms, ozone can cause respiratory distress and other health problems, and it can also attack vegetation. The concentration detected by the aircraft is significant, says Jaffe, because the pending federal standard for ozone is an 8-hour average of 80 parts per billion.
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