Smoggy Climbing: Haze Darkens View of Seoul

Climbers scale a rock face as a thick layer of pollution hangs over the Seoul skyline on Sunday. A Seoul-commissioned study in late 2011 said the wind from South Korea's northwest is responsible for nearly half of the microscopic particular matters in Seoul's air, blown in from heavily-industrialized northeastern China and fast desertifying Mongolia. The study said the other half originated locally or from neighboring municipalities.

— AFP - Getty Images