No time to breathe easy on air quality

Traffic is pictured on Highway 99 near Fresno, which has some of the nation’s worst air quality.
Traffic is pictured on Highway 99 near Fresno, which has some of the nation’s worst air quality. The Fresno Bee

California is the nation’s air pollution paradox.

We have the country’s dirtiest air, especially in the Central Valley and the Los Angeles basin. But we are also a national leader in efforts to improve air quality. And we’ve made more progress on that front than most other parts of the country.

All of this is evident in the latest “State of the Air” report from the American Lung Association, which issues the annual report card as part of its effort to lobby for tougher air quality standards and enforcement.

Unfortunately, California cities topped the list for the nation’s worst air quality by every standard measure. L.A. has the worst ozone pollution in the United States. And Fresno has the worst particle pollution, measured both on an annual basis and by the number of “bad air days” exceeding federal standards.

The bad air in L.A. is largely the result of its box-like topography and the region’s car culture, plus what remains of its heavy industry, including the ports of Los Angeles and Long Beach. But L.A. also has reduced its number of unhealthy air days by a third in the past 15 years, and even its high ozone levels are falling.

Fresno and the rest of the Central Valley also suffer from accidents of geography. Much of the tiny particle pollution produced on the coast is carried inland by prevailing winds. But the Valley’s agriculture industry generates its share of pollutants from heavy machinery, as does the truck traffic rumbling up and down the Valley.

Pollution from those diesel particles has improved in Fresno, the study showed, but things got worse in Bakersfield and Merced, among other places. So more work remains to be done.

But continued progress will be difficult, because so much has already been done and new technologies will be needed to reduce harmful emissions.

The state Air Resources Board is already talking about transitioning California’s freight transportation system to zero or near-zero emissions over the next two decades. The movement of goods now accounts for about half of the diesel particulate pollution and nearly half of the nitrogen oxide that forms ozone pollution, so the ARB’s goal is admirable. But achieving it will be expensive for public and private players alike.

Gov. Jerry Brown’s announcement Wednesday that he plans to propose more ambitious goals for the state’s reduction of greenhouse gases also will help, since most efforts to reduce the carbon emissions that cause climate change also will reduce the kind of emissions that pollute the air we breathe every day.

So the bad news is that California’s air is still unhealthy by national standards, and compared to everywhere else in the country. The good news is that it is much cleaner than it used to be, thanks to regulation of polluters.

And the sobering news is that, if we want air that doesn’t endanger children, older adults and people with chronic diseases, we are all going to have to help pay.