The cause of smog formation

First, the physical basic source of particulate matter.

China has the largest loess plateau in the world, and its soil texture is the easiest to produce granular dust particles.

Second, poor exercise leads to dust.

For example, the mud in the garden in the middle of the road and the soil on the roadside stones will flow to the road after raining or splashing water, which will produce a lot of dust after one hour of drying. Even if these particles fall back to the ground, they will be thrown over the city again because of the continuous passing of cars.

Thirdly, the basic source of dust and the process of movement difference gather in a certain spatial range, and particles finally gather with water molecules to form haze.

In more than 350 cities on the Loess Plateau in China, the three elements of smog structure are quite rich.

Turbid component

Haze is mainly composed of sulfur dioxide, nitrogen oxides and inhalable particles. The first two are gaseous pollutants, and the last particulate matter is the main reason for aggravating smog weather pollution. Together with the fog, they make the sky gloomy in an instant.

The abbreviation of particulate matter is PM, and Beijing monitors fine particulate matter (PM2.5), that is, pollutant particles with aerodynamic equivalent diameter less than or equal to 2.5 microns. This particle itself is not only a pollutant, but also a carrier of toxic substances such as heavy metals and polycyclic aromatic hydrocarbons.