It has snowed in many places recently, and it is said that the air pollution is slightly worse at th

After a sleet, the air in many northern cities seems to be less dirty. So, what happens to the air quality when the temperature plummets? Does snow make air quality better? And how can people take precautions?

In most cases, the air temperature at low altitude decreases with the increase of altitude, which promotes the formation of vertical convection in the atmosphere at high and low altitudes, which can accelerate the dispersion of pollutants. Sometimes, however, the temperature rises with altitude at some levels, when the atmosphere is "top-heavy" and stable, and combined with the influence of still winds, the air has neither horizontal nor vertical movement. The inversion layer acts like a cauldron lid that covers the low altitude near the ground, making it difficult for pollutants and water vapour to diffuse. This phenomenon mostly occurs in late autumn, when there are no strong winds and no heavy rainfall.

At this time, the sudden cold air not only brings a lot of particulate matter, but also increases the stability of the atmosphere, resulting in more serious pollution.

However, the howling cold winds and snowfall have attached particles to the air and landed on them, reducing the concentration of pollutants in the air.

Generally speaking, when it rains and snows or there is light rain or snow, the air quality cannot be improved immediately, so try not to open the windows at this time, otherwise the falling rain and snow will bring some pollutants into the room; If light rain or snow lasts for a short time, it is not effective in improving air quality; Prolonged rainfall or heavy rainfall is the only way to effectively improve air quality. After rain and snow, the air is fresh, pollutants are reduced, and ventilation can be carried out for a longer time. In the cooling weather without wind, rain and snow, and the smog in the air is heavier, outdoor exercise and activities should be minimized, especially for patients with respiratory diseases, the elderly or children, try to wear a thick mask when going out.

After the snowfall, the cold air is not strong, the wind is small, the snow melts quickly, the water vapor in the air increases, the humidity is very high, and the condensation forms a fog. Heavy fog sometimes has inverted weather, which is not conducive to the diffusion and dilution of pollutants, so air pollution will be serious.

When the snow is slow, the speed of the car is slow, and when the engine is running at low speed, the gasoline is prone to incomplete combustion, and the emission naturally increases more than usual. And the snow falls to the ground and accumulates and melts into muddy water, and the wheels will also bring up the pollutants, if the weather conditions after the snow day do not improve, the wind speed is small, resulting in poor horizontal diffusion conditions, so it is easy to have aggravated pollution**.

The relative humidity in the air is high during snowfall, and the pollutants in the air provide a large number of condensation nuclei for water vapor condensation, which also makes the pollutants unable to be effectively diluted and removed.

Air pollution can be severe, mainly during snowfall, and the flow of air is weak both horizontally and vertically.

Snowy days are heavily polluted because the water vapor in the air increases after snowfall, the humidity is very high, and it will condense to form fog, and the fog sometimes has inverted weather, which is not conducive to the diffusion and dilution of pollutants, so air pollution will be serious. After the snow, the cold air is not strong and the wind speed is small, resulting in poor horizontal diffusion conditions, so it is easy to have increased pollution**.

The relative humidity in the air is larger than that in snowfall, and the pollutants in the air provide a large number of condensation nuclei for water vapor condensation, which also makes the pollutants unable to be effectively diluted and removed.

In winter, the emission concentration of air pollutants is high and the intensity is high, especially in the northern region, the temperature is low, coal is mostly used for heating, the amount of coal burned is significantly increased, and the emission of soot and dust is accumulated in the inversion layer weather.

After the snow, the speed of the car is slower, and when the engine is running at low speed, the gasoline is prone to incomplete combustion, and the emission will increase more than usual, and the pollutants in the atmosphere will increase, and the pollution will be aggravated.

Due to the increase of water vapor in the air after snowfall, the humidity is very large, which will condense to form a fog that rolls and grinds away, and the fog sometimes has inverse weather, which is not auspicious and conducive to the diffusion and dilution of pollutants, so air pollution will be serious. In addition, because the nature of snow only has a clear effect on large particles, not only will it not be washed off after snowfall, but it will also absorb moisture and increase the concentration. <

Due to the increase of water vapor and high humidity in the air after snowfall, it will condense to form fog, and the fog will have inverse weather from time to time, which is not conducive to the diffusion and dilution of pollutants, so air pollution will be serious. In addition, since the nature of snow only has a cleaning effect on large particles, not only will it not be washed off after snowfall, but it will also absorb moisture and increase its concentration.

Hello, it is a pleasure to serve you and give you the following answers: A: 1

Causes: Air pollutants in polluted weather, such as sulphur dioxide and nitrogen oxides, combine with the water droplets in the snowflakes to form dissolved pollutants, reducing the solubility of the snowflakes and causing the snow to melt. 2.

Solution: (1) Reduce the emission of pollutants: ** The emission management of air pollutants should be strengthened and the emission of pollutants should be reduced to reduce the content of pollutants in snowflakes, so as to improve the solubility of snowflakes and make snow melt.

2) Improve air quality: Effective measures should be taken to improve air quality and reduce the content of air pollutants, so as to increase the solubility of snowflakes and make snow shiver only able to melt. 3.

Personal Tips: (1) We should strengthen our awareness of environmental protection and reduce the emission of pollutants to protect the environment, improve the quality of air caverns, and make snow melt. (2) We should participate in more environmental protection activities, improve environmental awareness, achieve green travel, and reduce pollutant emissions to protect the environment, improve air quality, and make snow melt.