Looking north to the ger district. Gers are felt huts. Mongolians just in from the countryside usually bring their ger into town and set up in the ger district to the north, where they burn dirty coal during the cold months to stay warm. That coal, in a hundred thousand + gers, plus the car exhaust from over a hundred thousand cars idling in traffic jams, creates a toxic smog that has been estimated to shorten lives by 5 or more years. Needless to say, we wear masks!
In the north of Ulaanbaatar is the ger district, where Mongolian nomads just moved to town live. There they burn dirty coal to stay warm in the cold winter, creating a smog that lingers over the city.