Clearing the Air

An Earth Day Celebration


When I talk about environmental trends at colleges, I often start with a question: "Has air pollution in the United States gotten worse or better over the past three decades?"

The majority—often a vast majority—of my audience will raise their hands in favor of the proposition that air quality has gotten worse. Polls consistently show that most Americans would join them in agreeing with that—completely false—notion.

A forthcoming study from air quality analyst Joel Schwartz does a great job spelling out the good news about air pollution, and explaining why the good news will get better. No Way Back: Why Air Pollution Will Continue to Decline will be released by the American Enterprise Institute (AEI) later this year. Schwartz debuted his analysis in a timely presentation at AEI the day before Earth Day. Such good news about environmental trends is, alas, strangely rare during the annual celebration of environmental awareness—and environmental fearmongering.

Using uncontroversial data from agencies like the U.S. Environmental Protection Agency (EPA) and the California Air Resources Board, Schwartz shows that air pollution news has been good across the board for decades now. Since the mid-1960s the best available measurements show that sulfur dioxide levels have fallen by more than 80 percent, carbon monoxide levels are down more than 75 percent, nitrogen dioxide levels dropped over 40 percent, ozone levels decreased nearly 50 percent, and the level of total particulates (smoke, soot, dust) is down by more than 60 percent.

In the 1980s, the EPA also started measuring smaller particles in the air, which are believed to have graver health consequences than some of those older pollution markers. Levels of those tiny terrors have declined nearly 30 percent. By almost any standard, air quality greatly improved between 1970 and 2000, even as U.S. population grew by 39 percent, energy use increased by 42 percent, total vehicle miles driven jumped by 143 percent, and gross domestic product soared by 149 percent.

There is no connection any longer between increased population, industrial production, energy consumption, or car use and increased air pollution. The already low air pollution levels in the United States will inevitably drop much further over the next two decades. As Schwartz explains, "most future pollution reductions will come from things we have already done." New technologies and regulations already put in place will continue to clear our air.

New cars already pollute far less than older cars, so as older cars are replaced by cleaner new cars, the air will continue to clear. "Almost all pollution from gasoline powered vehicles will disappear over the next 20 years," Schwartz declares. Simply by implementing the standards now on the books and through the normal process of automobile fleet turnover, total average emissions from all autos will decline by at least another 85 percent over the next two decades. While most of the improvements in air quality are the result of regulations, Schwartz notes that even when enforced air quality standards did not change between 1982 and 1992, the amount of pollutants emitted by automobiles continued to decline each year, probably as a result of improved air and fuel mixing technologies in newer cars.

Some environmentalists fear that the effects of "suburban sprawl" and increasing numbers of gas-guzzling SUVs will halt the progress in reducing air pollution. But Schwartz notes that as the percentage of SUVs grew from 31 percent to 38 percent and gasoline use increased by 12 percent in California between 1994 and 2001, total emissions still continued their steep drops. Hydrocarbons were down by more than 60 percent, nitrogen oxides by over 40 percent, and carbon monoxide by 55 percent.

Of course past performance is no guarantee of future results, as we've all learned from the stock market. So to account for the increasing popularity of SUVs and more miles traveled, Schwartz's analysis assumed that gasoline consumption would rise over the next 20 years at 2 percent per year. In recent years gas consumption has only increased by around 1.7 percent annually. Based on that assumption, what would have been a 90 percent decline in the emissions rate becomes an 85 percent reduction—not a new air pollution crisis by any means.

"The vast majority of health benefits from reduced air pollution have already been achieved in most of the U.S.," Schwartz says. But if we want even cleaner air faster, there are a couple of relatively cheap things we can do now. First, get the most polluting cars off the road. Between 45 and 60 percent of smog precursors are emitted by just 5 percent of the cars on the road. These hyperpolluters could be detected using remote sensing technologies and their owners offered money to scrap them. Second, policy makers should eschew any policy that makes new cars more expensive.

For example, a proposal to raise the prices of conventional cars and use the extra money to lower the prices of electric cars—which are estimated to cost $17,000 more than conventional cars—would be counterproductive. Since new conventional cars will be virtually pollution-free soon, raising their prices will have the perverse effect of encouraging drivers to hold on to their older, more polluting, jalopies longer, thus increasing overall emissions.

In the face of the overwhelming evidence to the contrary, why do the majority of Americans still believe that air pollution is getting worse? When crime rates fall, mayors, police chiefs, and district attorneys are eager to spread the news and take the credit. But when pollution levels fall, environmentalists and environmental bureaucrats show a peculiar reluctance to cheer. Schwartz suggests that the difference is that the environmental movement uses scare stories to raise money for their campaigns: no crisis, no money, no movement. In other words, Americans believe that air pollution is getting worse because some people make a living peddling that misinformation.

The bottom line, says Schwartz: "Not only will air pollution not increase, there's virtually no way to stop large decreases in air pollution in the future." That's Earth Day news worth celebrating.