You were in Beijing right? It depends on how coal is burned and who burns it. Hebei province which encircles Beijing is one of the poorest places in China as well as the most densely populated. Natural gas is unaffordable to the rural people there so they burn a hell lot of coalhttps://twitter.com/Molson_Hart/status/1195880423974416384 …
This happened to me three times: once in tianjin, once in Shanghai, and once in Liaoning. It’s not just a Hebei issue. It’s not like dongbeiren are somehow more educated or sensible about their energy usage than he Hebeiren. I’ve been to rural liaoning and tier 3-4 city hebei.