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Two Cheers for the Clean Air Act

Friday, September 17, 2010

This week marked the 40th anniversary of its passage with scarcely any observance of the magnitude of progress under the legislation.

This week, America’s chattering class is celebrating the largest single public policy success story of the last half century—or would be, if anyone knew about it.

The drop in the crime rate? Nope; although impressive, that trend is only about 20 years old. The drop in welfare dependency? Nope: again, only about 15 years old. The trend I’m referring to is over 40 years long: cleaner air.

Seymour Garte, professor of environmental and occupational health at the University of Pittsburgh and author of the fine 2007 book, Where We Stand: A Surprising Look at the Real State of Our Planet, relates the story of attending a professional conference in Europe and being struck by a speaker’s data showing steadily declining air pollution trends. He was surprised by the data, and even more surprised to hear the speaker say, “Everyone knows that air pollution levels are constantly decreasing everywhere.” Garte looked around the room. He writes:

I was not the only nonexpert there. Most of my other colleagues were also not atmospheric or air pollution specialists. Later I asked one of them, a close friend, if he had known that air pollution levels were constantly decreasing throughout Europe and the United States on a yearly basis. “I had no idea,” he said. It certainly was news to me. Even though I was a professor of environmental health and had been actively involved in many aspects of air pollution research for many years, that simple fact had somehow escaped me . . . I had certainly never seen it published in the media.

If an environmental specialist is ignorant of the trends, imagine a hapless reporter or politician. Yet the 40th anniversary of Clean Air Act’s passage came this week with scarcely any observance of the magnitude of progress under the legislation. As Figure 1 shows, the magnitude of the reduction in air pollution is larger than reductions in the crime rate or in welfare rolls—both rightly and loudly celebrated as major social policy successes.

Hayward 9.17.10 Fig.1

One reason the steady improvement in air quality has been unappreciated is that it has come in small, steady increments—on the order of 1 to 3 percent per year—rather than through any large breakthroughs. With a few notable exceptions, media coverage of air pollution is generally abysmal. Advocacy groups (“crisis entrepreneurs” might be a more accurate nomenclature) with an interest in public misperception distort air quality data to reinforce public anxiety. Although the Environmental Protection Agency (EPA) publishes a succinct and accessible annual report about air quality trends that touts the nation’s progress (see the most recent report), it never receives much media coverage.

A review of the data reveals four main findings about air pollution trends:

The magnitude of the reduction in air pollution is larger than the reductions in the crime rate or in welfare rolls.

Virtually the entire nation has achieved clean air standards for four of the six main pollutants regulated under the Clean Air Act (carbon monoxide, sulfur dioxide, nitrogen oxides, and lead). The only pollutants where clean air standards are still widely exceeded are ozone and particulates.

• In the case of ozone and particulates, the areas of the nation with the highest pollution levels have shown the greatest magnitude of improvement. The average ambient declines in pollution on the national scale understate the magnitude of improvement in the worst areas. Los Angeles, for example, used to exceed the 1-hour ozone standard about 175 days a year in the 1970s; today, L.A. exceeds the 1-hour standard fewer than 20 days a year, and peak ozone concentrations on the worse days are two-thirds below their peak levels in the 1970s.

• The chief factor in air pollution reduction has been technological improvement, mostly in “process efficiency” such as more complete fuel combustion, but also in control technologies that capture emissions, such as power plant “scrubbers” and catalytic converters on automobiles. Regulatory mandates played a prominent role in prompting some of these technological changes, but many were the result of market forces and economic growth, as can be seen by the fact that air pollution began dropping in the United States in the mid-1960s—before the first Clean Air Act passed.

One reason why the steady improvement in air quality has been unappreciated is that it has come in small, steady increments.

The long-term trend of improving air quality is certain to continue. Government air quality models project significant decreases in emissions over the next 20 years as technology improvement and equipment turnover continue.

Table 1 displays the EPA’s calculation of the improvement in average ambient air quality and emissions for the nation as a whole from 1980 through 2008 for the six main air pollutants targeted under the Clean Air Act. These reductions are all the more impressive when viewed in comparison with the increase in economic output, population, energy use, and driving since 1990, displayed using EPA numbers in Figure 2.

Hayward 9.17.10 Table

Hayward 9.17.10 Fig.2

Why only two cheers? The EPA’s lumbering bureaucracy will prevent a third cheer as many regulations were unnecessarily costly or based on dubious scientific assessment. Like the proverbial French generals fighting the last war and erecting wasteful Maginot lines, the EPA is bent on contracting air pollution standards tighter and tighter, and beyond the point where the benefits exceed the costs. (The nominal cost of air quality improvements is well above $1 trillion since 1970.)

But even with these important caveats about bureaucratic inertia, we should all celebrate our ability to take a deep breath of clean air.

This article is adapted from the forthcoming "Almanac of Environmental Trends," to be published in November.

Steven F. Hayward is the F.K. Weyerhaeuser Fellow at the American Enterprise Institute.

FURTHER READING: Hayward recently explored “The Irrelevance of Modern Political Science,” depicted “Environmentalists as Battered Spouses,” discussed “Trying to Capture that Old Earth Day Magic,” and detailed temperature problems with climate change in “Unsettling the Settled Science.” He offers “A Cool Look at the Cold War,” explains “How to Think about Oil Spills,” and outlines “The Churchill Test.”

Image by Rob Green/Bergman Group.

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