Before the 2008 Olympics, Beijing worked hard to clean up its image and its air, going so far as to temporarily shutter factories and put new restrictions on cars. By all accouts, the efforts worked, with most visitors and althletes treated to a string of blue sky days in China's notoriously smoggy capital. But now that things are back to normal, how is Beijing doing on keeping the air clean? Check out this new project of Asia Society's China Green that matches photos of the sky in Beijing and New York for a weekly head-to-head.
Photos speak loudly on this issue, but here's some science. Last month NASA released this incredible map of particulate matter concentrations in the air around the world. New York doesn't look so bad, but Beijing on the other hand...