Non-Global-Warming Pollution Problematic

In this era of inconvenient truths and carbon footprints, it seems almost baroque to talk about something as seemingly trivial as old-fashioned air pollution. After all, its effects are largely local, often short-term, and far more readily addressed by environmental solutions.

But as the American Lung Association’s new State of the Air report shows, just because it’s not as common a concern doesn’t mean it’s something that should be ignored; more than 40 percent of Americans currently live in areas of unhealthy ozone or particulate pollution.

The Sate of the Air report breaks pollutants into three major categories by type. The first is ozone, which forms when nitrate emissions react with air and sunlight, and can irritate asthma, lead to chest pain, and permanently impair lung function. The second two types are short-term and long-term particulate pollution, formed by extremely tiny pieces of soot, diesel exhaust, metal, road dust, or any other solid matter emitted into the air through a variety of processes.

“Particulate has been associated with more deaths than ozone. If you had to pick your poison, you'd rather have ozone than particulate matter,” says George Leikauf, a professor at the University of Pittsburgh’s School of Public Health. The Pennsylvanian city was something of a surprise as the top spot in this year’s short-term particulate matter rankings, even though, according to Leikauf, most of the city’s pollution is actually carried on the wind from power plants in Ohio.

This highlights a major difference between traditional air pollution and global warming emissions: air pollution is highly localized. Strategies like cap and trade, in which pollution levels are capped by the government, and polluters are given the ability to buy, sell, and trade pollution credits if their emissions are higher or lower than the government levels, aren’t particularly useful. Pittsburgh’s air becomes no cleaner if the Ohio plants polluting it buy permits from cleaner plants in another part of the country, even if overall amount of pollution nationwide decreases.

Still, because the effects of these more traditional forms of air pollution are immediately noticeable, they help draw public attention to the longer-term problem of global warming. Many of the same processes that create carbon emissions, such as over-reliance on automobiles or coal power plants, also lead to pollution by ozone and particulate matter. Car-heavy cities such as Houston, Dallas and Los Angeles have dominated the State of the Air listings, and this year has proven no exception.

The need to address traditional air pollutants is especially pressing in the context of climate change, because their accumulation in the atmosphere may in fact be making the effects of global warming harder to detect. The phenomenon, known as global dimming, occurs as particulate pollution reflects sunlight back into space, and temporarily reduces the obviousness of global warming.  This provides fodder for climate change deniers, and sets the world up for a sudden and pronounced change when the continued increase over global carbon levels beings to overcome the effects of global dimming.

Photo by Ben Amstutz