The cause of smog

There are four meteorological factors that form haze weather:

First, the relative humidity is relatively high, that is, there must be quite a lot of water vapor in the air, and the water vapor content is relatively high;

Second, the atmosphere is in a static state, which is not conducive to the diffusion and dilution of suspended particles in the atmosphere and is easy to accumulate around urban areas and suburbs; Third, there is an inversion in the vertical direction, so it is difficult for suspended particles in the air to drift to high altitude and be blocked at low altitude and near the ground; Fourth, there must be cooling conditions. Meteorological factors are the external causes of smog pollution.

Haze can happen all year round.

Haze can happen all year round, not just in winter. For example, sandstorms in the north in spring, photochemical reactions in summer and straw burning in autumn will all cause smog, and smog is more likely to form in winter due to special climatic conditions.