Why is the smog so serious?

As autumn and winter enter in previous years, haze weather will always occur frequently. Recently, the intensity of cold air activity affecting Nanjing, including the middle and lower reaches of the Yangtze River, has been relatively weak, and the atmosphere has tended to be in a relatively static state. Horizontal diffusion conditions and vertical diffusion The conditions are relatively poor. Pollutants continue to accumulate in the atmosphere and are difficult to self-purify or remove in a short period of time.

The main reason is the current vehicle exhaust emissions. Industrial waste gas pollution is serious. In addition, northern regions need heating in autumn and winter. A large amount of coal burning makes the air worse. As people pay more and more attention to PM2.5 As a result, some scientific research institutes and technology companies have also begun to intervene and have linked up with the environmental protection department. There is a PM2.5 data cloud monitoring platform at Yunchuang Storage Center in the eastern suburbs of Nanjing. Which city in the country has the highest PM2.5 concentration and which city has the lowest concentration can be known here in real time.