Just as drought and dust were on our minds here last week, Forester’s publisher pointed out another dust-related concern. This article in the New York Times reports on a study showing that air pollution from China’s manufacturing plants is arriving in measurable quantities on the West Coast of the US.
It’s well known that airborne particulates can travel long distances. An article in Erosion Control back in 2001 documented airborne sediment reaching the northeastern US from the Sahara Desert. The cause in that case, however, was a huge dust storm in northwest Africa that stirred up tons of sand, which was eventually carried west by trade winds—not necessarily an everyday occurrence. The airborne particulates China is sending our way appear to be an ongoing problem. And while parts of China do experience desertification and severe erosion problem that lead to blowing dust—that same EC article discusses some of them—the pollutants this latest study focuses on come from manufacturing processes. The US, of course, is a huge consumer of the items produced there.
Dust, ozone, and carbon—particularly so-called “black carbon,” which is not easily removed from the atmosphere by rainfall and which is implicated in a number of diseases, from asthma to cancer to heart disease—are the main pollutants of concern. And while the effects in the US are measurable—Los Angeles, for example, averages at least an extra day of smog exceeding federal ozone limits—they’re much worse at the source. The study’s authors estimate that manufacturing goods for export just to the US accounts for more than 7% of the sulfer dioxide, nearly 6% of nitrogen oxides, 4.6% of carbon monoxide, and 3.6% of black carbon emissions in China.
Ironically, outsourcing much of our manufacturing to China has actually improved air quality for much of the US—the more densely populated eastern parts, according to the study.