Clearing the Air on Climate and Smog

By Lisa Aliferis

Why climate change and public health policy make good chemistry

A major study released today in Fresno details the direct link between higher levels of air pollution and asthma-related ER and hospital admissions. So, what’s that got to do with climate change? Plenty.

Sandy Huffaker / Getty Images

Tourists snap photos of a murky sunset in San Diego

“There’s a division in the public’s mind between global warming and health effects of pollution,” says Dimitri Stanich of the California Air Resources Board.

In reality, there’s significant overlap. Some components of air pollution shown to have harmful warming effects on the planet are also harming people, especially children, right now.

Let’s start with ground-level ozone. Ground-level ozone is different from the ozone layer, which lies about 15 miles above the earth (not exactly ground level). The ozone layer shields us from most of the sun’s harmful rays. Ozone is good in the atmosphere but bad, in many ways, at or near ground level.

Ground-level ozone is not part of air pollution itself. Instead, it is formed by a complex chemical reaction starting with the nitrogen dioxide (NO2) component of air pollution. That chemical reaction is especially strong when the air is calm and the sun is shining (California’s Central Valley in the summer, anyone?). This stuff is terrible for your lungs.

“Ozone has the same corrosive aspects of bleach,” explains Bonnie Holmes-Gen, senior policy director for the American Lung Association in California. “When people breathe it in, it damages the lining of the lungs. It’s like getting a sunburn on the lungs. It triggers coughing, wheezing and asthma attacks,”

Ground-level ozone is also a greenhouse gas. So, while it’s harming people today, it’s simultaneously helping to warm the planet. If that’s not enough, ground-level ozone’s corrosive properties harm crops, too. The Central Valley may be the nation’s salad bowl, but it’s ground zero for ground-level ozone.

Then there’s “black carbon.” If you think that sounds ominous, you’re right.Tiny particles of black carbon can lodge deep in a person’s lungs (bad) or circulate in the air and contribute to global warming (also bad). And, in a triple whammy, if black carbon particles land on arctic snow, they can accelerate the ice melt. Scientists say black carbon is a major contributor to climate change, perhaps second only to CO2. Black carbon comes from, among other things, the burning of fossil fuels, the stuff that comes from tail pipes and smokestacks.

Sunday’s New York Times featured a depressingly detailed account of Americans’ waning interest in global warming. Climate skepticism is on the rise, at least in political circles. While skepticism about the health effects of air pollution isn’t polled as much, it seems reasonable to think there’s little argument there.

This is where we get to what policymakers call “co-benefits.” Ms. Holmes-Gen points out that ground level ozone and black carbon are both fairly short-lived in the environment. “It’s a huge bang for the buck. If we reduce air pollution, we’ll see an immediate health benefit and we get warming pollutants out of the air, too.”

Lisa Aliferis is a health news editor at KQED. The complete smog & health study referred to at the top of this post is available as a PDF download from Fresno State University.

  • http://www.killian.com/earl/editorials.html Earl Killian

    Black carbon is one reason we should change our vocabulary. Instead of talking about “greenhouse gases” we should talk about “greenhouse pollution”, since black carbon is not a gas.

    To my mind, “pollution” is also a stronger word than “gas” and so helps frame things appropriately.

  • S.W. Ela

    Please provide readers to the correct link to the Fresno study.

    • ScientificFacts

      And Mundane, you know this because you’ve spent decades compiling data of air contaminant levels and the temperature at thousands of locations around the globe, and have collaborated with hundreds of other neutral scientists to conclude it’s all a lie, right?

  • mundane

    This “study” has no genuine scientific basis. For starters, there is absolutely ZERO observable phoenomenon, just another set of assumptions fed into a computer. Just like all of climate change pseudo-science. Propaganda, not science.

  • Craig Miller

    @SW: This link has been corrected and should work for you now, thanks.

  • S.W. Ela

    @Craig: Thank you!

  • http://www.buchete.ro Florarie

    I didn’t heard about black carbon by now. I thought that the main reason of global warming was CO2 that came out from many types of fuels. But it seems that the main cause of global warming and all the climate changes is black carbon.

    • Lisa Aliferis

      @Florarie: Actually, CO2 is still the #1 contributor to global warming. I didn’t include it in this post, because its public health effects are still limited. (Health effects may well occur down the road if the planet continues warming).

  • http://alisoviejosmogcheck.com aliso

    Wow that’s a brown sunset for sure.