Ozone from Asia contributes to US West Coast air pollution

Transboundary pollution: Air pollutants emitted by China’s industries, such as this iron ore powder and coke plant in Hebei province, can travel all the way to the United States West Coast. Photo: EPA

Researchers attribute dirty air to factors other than local industry.

High above the Big Sur coast in California, Ian Faloona is finding pollution on the edge of the continent, a place that should have some of the country’s cleanest air. From an astronomical observatory on Chews Ridge in the Santa Lucia Mountains, the atmospheric scientist from the University of California, Davis, has for the last three years measured ozone, the lung-damaging gas in smog, as it arrives to California.