How is smog formed? How is smog formed?

Haze is caused by the excessive content of particulate matter (particulate matter) in the air, and most of the residues emitted through combustion in the process of daily power generation, industrial production, automobile exhaust emissions, etc., mostly contain fine particulate matter, which is a general term for solid particles or droplets with a diameter of less than or equal to microns in the air, which can enter the lungs with breathing, so it is also called particulate matter that can enter the lungs.

Poor or poor air flow is the main factor in the formation of haze.

The air doesn't move, so tiny particles collect in the air, which is why the smog dissipates as soon as the air gets cold.

Car exhaust emissions: There are more and more cars in the city, and it can be seen from the number of parking spaces that the more cars there are, the more exhaust emissions there are, and naturally the air quality will get worse and worse, resulting in haze weather.

The humidity in the air is too low, and people will carry dust on the ground when they move.

There are four meteorological factors that contribute to the formation of haze weather:

First, the relative humidity is relatively large, that is, there must be considerable water vapor in the air, and the water vapor content is relatively high.

Second, the atmosphere is in a static and stable state, which is not conducive to the diffusion and dilution of suspended particulate matter in the atmosphere, and is easy to accumulate in urban areas and suburbs.

Third, there is a temperature inversion in the vertical direction, and the suspended particulate matter in the air is difficult to drift to the high altitude and is blocked at low altitude and near the ground.

Fourth, there should be cooling conditions, etc., and meteorological factors are the external factors that form haze pollution.

Haze grading:

1. Slight haze: the relative humidity of the air is less than or equal to 80, and the visibility is greater than or equal to 5 km and less than 10 km.

2. Mild haze: the relative humidity of the air is less than or equal to 80, and the visibility is greater than or equal to 3 km and less than 5 km.

3. Moderate haze: the relative humidity of the air is less than or equal to 80, and the visibility is greater than or equal to 2 km and less than 3 km.

4. Severe haze: the relative humidity of the air is less than or equal to 80, and the visibility is less than 2 kilometers.

1. Exhaust emissions are the most important and direct factors leading to the occurrence of haze weather. Exhaust emissions include exhaust emissions from various automobiles, muck operation vehicles, private cars, etc., as well as industrial exhaust emissions such as thermal power generation, exhaust emissions from residents' use of coal and natural gas, and exhaust emissions from farmers' burning of straw, straw and other crop residues.

2 We all know that surface plants have an important role in conserving water sources and preventing soil erosion, affected by climate and human factors, the trend of desertification in China is obvious, and the desertification of the surface leads to dust, which is also an important factor leading to haze.

3 The main component in haze is aerosols, and the suspension of aerosols in the air is affected by meteorological conditions. For example, in places with a lot of rainfall in the south, there has been less and less precipitation in recent years, and the air dust has become more and more serious, thus aggravating the haze. In North China, the winter wind has been weak in recent years, and the haze "can't be blown away", so last year the Beijing-Tianjin-Tangzhou region became the hardest hit area of China's haze.

4 In order to revitalize the declining economy, infrastructure construction is being carried out all over the country, especially the renovation of subways, railways and highways. Coupled with the real estate bubble, urban expansion, and construction dust have also become an important factor in the severity of smog.

1.It's car exhaust. Large vehicles that use diesel fuel are "repeat offenders" of PM10 emissions, including large buses, shuttle buses of various units, and large transport trucks.

Although gasoline-powered small cars emit gaseous pollutants, such as nitrogen oxides, they can easily be converted into secondary particulate pollutants in foggy weather, aggravating smog. The exhaust of motor vehicles is the most important component of haze particles, and the latest data show that motor vehicle exhaust, coal, dust, and industry account for the smog particles in Beijing. However, with the advancement of automobile technology and the rise of oil quality, environmental managers have found that motor vehicle exhaust does not play a decisive role in the formation of haze weather, but as some cities with large car ownership, managers still need to control motor vehicle emission standards to avoid the formation of haze weather.

2.In the north, the exhaust gases produced by burning coal for heating in winter.

3.Exhaust gases emitted from industrial processes. For example, metallurgy, kilns and boilers, mechanical and electrical manufacturing, as well as a large number of exhaust gases emitted from the combustion of kilns for automobile repair and painting and building materials production.

There are several reasons for the formation of haze weather.

1.The main factor is when the atmospheric air pressure is low and the air is not flowing. Due to the non-flow of air, tiny particles in the air accumulate and float in the air.

2.The ground is dusty, the air humidity is low, and the people and traffic on the ground stir up the dust.

3.Automobile exhaust is the main pollutant emission, and in recent years, there are more and more cars in the city, and the emission of automobile exhaust is a factor of smog.

4.Secondary pollution produced by the factory.

5.Pollutants such as CO2 emitted from heating in winter.