Clean air makes for more global warming?

NPR:

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 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.

"The problem is that we're cutting the cooling pollution as we make our air cleaner," he says.

Some scientists, he says, are confident that this is connected to global warming, but they don't know how large the effect is. "That's the frightening thing, because if it's a big cooling effect, it means that we've been actually warming the planet more than we know," Kintisch says. "As we take away that unexpectedly helpful cooling mask, we're going to be facing more global warming than we expected.

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That is it. We are doomed by cleaning the air. Global warming may not be running out of sharks to jump but it appears to be caused by almost anything and at the same time be the cause of everything that goes wrong.