科学美国人60秒:Future Smog Looks More Persistent

Polluted air causes more than 2.6 million people to die prematurely each year. And when the smog builds up in Los Angeles or Beijing it sits there until a cleansing rain or a clearing wind freshens the air.
 
So what does the future hold for the number of days in which the air is not fair? According to some new computer model simulations, nothing good. The atmosphere is going to get more stagnant thanks to increasing levels of greenhouse gases and the heat they trap, leading to as many as 40 more bad air days annually around much of the globe.

That's according to a study in the journal Nature Climate Change. [Daniel E. Horton et al, Occurrence and persistence of future atmospheric stagnation events]

India will be worst hit by such atmospheric stagnation, according to the computers. But nobody escapes, including the U.S.
 
Of course, there’s a way to ward off this predicted outcome. It already made sense to try to stop pollutants like soot and ozone from entering the air in the first place and to cut back on the emissions of greenhouse gases like carbon dioxide and methane. Now it seems we’d get the additional benefit of preventing the increase in the number of bad air days. Just trying to clear the air here.
 
—David Biello
 

 
[Scientific American is part of Nature Publishing Group.]