Weather background of air pollution diffusion

The spread of air pollution is related to a wide range of weather background. When an area is controlled by a low-pressure center, the air moves upward and there are many cloudy days. Usually, the atmosphere is neutral or unstable, which is conducive to the diffusion and dilution of pollutants. When an area is controlled by a high-pressure center, the air sinks, often forming a subsidence inversion, which is not conducive to the upward diffusion of pollutants. If the high pressure moves slowly and stays in a certain area for a long time, the pollutants will not spread for a long time. Especially when the weather is clear, it is easy to form radiation inversion at night, which is not conducive to the diffusion of pollutants, and pollution hazards are easy to occur at this time. If unfavorable terrain conditions are added, serious pollution incidents will often occur.