Winter mornings in Ulaanbaatar have a misty hue. Smog obscures visibility and chokes streets with pollutants, including ground-level ozone, particle pollution, carbon monoxide and sulfur dioxide.

Winter mornings in Ulaanbaatar have a misty hue. Smog obscures visibility and chokes streets with pollutants, including ground-level ozone, particle pollution, carbon monoxide and sulfur dioxide.