The dust in the Martian atmosphere is comparable to that of a moderately smoggy day in Los Angeles.

CNN: Mars' geology 'more like Earth than the moon'

Coastal residents of the western United States should hunker down for a smoggy summer and fall, NASA scientists say.

CNN: Western U.S. to get smoggy summer, fall

Despite a smoggy start to the day, visibility at the Bird's Nest improved in the hours before the event began.

BBC: Games begin with spectacular show

Breathing particulate-laden (aka smoggy) air may be hardening your arteries faster than normal, according to research published today in PLOS Medicine.

FORBES: Is Breathing Smoggy Air Hardening Your Arteries?

The notoriously smoggy skies of Los Angeles are a little bit cleaner than you might expect, at least in one respect.

FORBES: Los Angeles Pollution From Car Exhaust Is Down 98%

Does Los Angeles seem less smoggy these days?

ENGADGET: Inhabitat's Week in Green: a locomotive that runs on hydrogen, honey detective and a 30 mph-capable hover bike

When computer models gave him the power to spin up winds on planets of the mind, his first big topic was a study of the net effects of smoggy pollutants in the atmosphere, which cool the planet down, and the carbon dioxide which warms it up.

ECONOMIST: Steve Schneider