Causes of smog formation in Beijing

There are many reasons for smog in Beijing, such as automobile exhaust, industrial production and building dust. The main reason is that due to the large amount of pollutants, the air is rich in a large number of particulate matter, which condenses with fog water to form a wide range of smog. 1, Meteorological reasons Large-scale haze weather mainly appears in a large-scale atmospheric circulation situation with weak cold air and good water vapor conditions, and the low altitude near the ground is still wind and breeze. Controlled by the quiet weather near the ground, regardless of the size of the city, the pollutant emissions of local energy consumption for transportation, life and production are constantly accumulating at low altitude. At the same time, due to the high humidity and high water vapor content in the haze weather, the droplets provide adsorption and reaction sites, which accelerates the transformation of reactive gaseous pollutants into liquid particulate components, and particulate matter also easily acts as condensation nuclei to accelerate the formation of haze, and the interaction between them quickly forms pollution. 2. There is inversion in the vertical direction of the atmosphere. The inversion layer is like a pot cover over a city. This inversion phenomenon that the upper air temperature is higher than the lower air temperature limits the vertical movement of the lower air, making it difficult for pollutants to drift to the upper air and be blocked at the lower air and near the ground. Harmful substances emitted from industrial production, motor vehicle exhaust, building construction, heating in winter, coal burning, etc. are difficult to spread, which leads to a significant decline in air quality and pollution to the atmosphere, thus leading to haze weather.