From a report at the link below:
The city of Harbin closed schools, canceled flights and halted buses.
Viability shrank to less than half a football field and small-particle pollution soared to a record 40 times higher than an international safety standard in one northern Chinese city as the region entered its high-smog season.
The photos are from various places in China where smog envelops large cities when the heating season begins and coal-fired furnaces are turned on in factories and homes.
Winter typically brings the worst air pollution to large China cities because of a combination of weather conditions and an increase in the burning of coal for homes and municipal heating systems, which usually starts on a specific date. For the large northern city of Harbin, the city's heating systems kicked in on Sunday.
Full report here.