Haze is composed of particles such as dust, sulfuric acid, nitric acid, and organic hydrocarbons in the air. It can also make the atmosphere cloudy, blurred vision and lead to deterioration of visibility, if the horizontal visibility is less than 10,000 meters, the visual range barrier caused by this non-aqueous aerosol system is called haze (Haze) or dust-haze, and the Hong Kong Observatory is called Haze.
Sulfur dioxide, nitrogen oxides and respirable particulate matter are the main components of smog, the first two are gaseous pollutants, and the last particulate matter is the culprit that aggravates the pollution of smog weather. They combine with the fog, making the sky instantly gray. Particulate matter is abbreviated as PM, and Beijing monitors PM2.5, which is a pollutant particle with an aerodynamic equivalent diameter of less than or equal to 2.5 microns.
Smog is mainly composed of sulfur dioxide, nitrogen oxides and respirable particulate matter, which combine with the fog to make the sky instantly gloomy and gray. Particulate matter is abbreviated as PM, and Beijing monitors fine particulate matter (PM2.5), which is aerodynamic equivalent diameter of 2.5 microns or less of pollutant particles. This particle itself is both a pollutant and a carrier of toxic substances such as heavy metals and polycyclic aromatic hydrocarbons.
The distribution of haze particles is relatively uniform, and the scale of haze particles is relatively small, from 0.001 microns to 10 microns, the average diameter is about 1 to 2 microns, and the naked eye cannot see the particles floating in the air. Due to the haze composed of dust, sulfuric acid, nitric acid and other particles, it scatters more light with a longer wavelength, so the haze looks yellow or orange-gray.
What are the main smog pollutants
Smog pollutants are mainly: sulfur dioxide, nitrogen oxides, inhalable particulate matter. The first two are gaseous pollutants, and the last particulate matter is the culprit that aggravates the pollution of smog weather.
The main sources of pollutants are: automobile exhaust, coal combustion, industrial emissions and building dust.
What are the causes of regional smog pollution
There are three reasons for this:
First, the total amount of pollutants emitted from pollution sources such as coal burning, motor vehicles, industry, and dust in the central and eastern parts of the mainland is large, which is the internal cause of serious regional heavy pollution. In particular, since December 2012, the entire North China region has been in extremely low temperature weather, and the emissions of coal-fired heating have increased accordingly due to low temperatures.
Second, extremely unfavorable pollution diffusion conditions are the direct cause of the haze pollution process. Due to the weak cold air activity, the wind in the North China Plain, the middle and lower reaches of the Yangtze River Plain and other areas is small, the atmospheric temperature is stable with the distribution of height (atmospheric junction), and some areas are affected by precipitation and evaporation of water vapor on the ground, making the relative humidity of the air near the ground larger and larger. In these areas, the night sky is clear and cloudless, and the radiation cooling amplitude is more obvious, which is conducive to saturation and condensation of humid air and the formation of fog. Under such stable meteorological conditions, pollutants in the air are not easy to spread outward in both horizontal and vertical directions, so that pollutants accumulate in the shallow layers of the atmosphere, resulting in more and more serious pollution conditions.
Third, the superposition of regional pollution and local pollution contributions, PM2.5 pollution regional and related regional pollution transmission, is also an important factor in the formation of smog pollution.
What are the pollutants in smog weather
1. Automobile exhaust is the main pollutant emission, in recent years, there are more and more cars in the city, and the emission of automobile exhaust is a factor of smog.
2. Secondary pollution produced by the factory.
3. CO2, SO2 and other pollutants emitted by winter heating.
In life, you should drive less, it is best not to drive, ride more bicycles, electric vehicles, take buses, reduce the use of coal, increase investment in factory purification systems and other measures to control the formation of smog.