NPR: Could Cleaner Air Actually Intensify Global Warming? [View All]

Could Cleaner Air Actually Intensify Global Warming?

by NPR Staff

April 25, 2010

As much of the world marked Earth Day this past week, the Environmental Protection Agency reported that air pollution has declined dramatically over the last 20 years. It sounds like good news, but science writer Eli Kintisch argues that there's a surprising downside: Cleaner air might actually intensify global warming.

"If we continue to cut back on smoke pouring forth from industrial smokestacks, the increase in global warming could be profound," Kintisch writes in an opinion piece for the http://www.latimes.com/news/opinion/commentary/la-oe-kintisch18-2010apr18,0,3774828.story">Los Angeles Times.

Kintisch isn't talking about greenhouse gases like carbon dioxide; he's talking about another kind of pollutant we put in the sky -- "like aerosols from a spray can," he tells NPR's Guy Raz. "It turns out that those particles have a profound effect on maintaining the planet's temperature."

Greenhouse gases and aerosol pollutants work in opposing ways on the Earth's climate, Kintisch explains. "The greenhouse gases warm the planet when they're emitted, because they absorb heat reflected up from the ground -– the greenhouse effect. These aerosols, though, do the opposite. They block sunlight, they make clouds more reflective -- and by doing that, they actually cool the planet.

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