The steps of a sandstorm and how it is formed

SandstormsIt is a weather phenomenon in which strong winds blow up a large amount of dust and sand on the ground, making the air very turbid and the horizontal visibility is less than 1 km; Strong sandstormsIt is a weather phenomenon in which high winds blow dust and sand on the ground, making the air blurry and turbid, and the horizontal visibility is less than 500 meters.

Sandstorm weather process: In the same weather process, sandstorm weather occurred at the same observation time at 3 or more national basic (quasi) stations in China's weather forecast area;

Severe sandstorm weather process: In the same weather process, three or more national basic (quasi) stations in China's weather forecast area have severe sandstorm weather at the same observation time.

Precipitation is generally low in dry areas in winter and spring. And the surface is unusually dry and loose, and the resistance to wind erosion is also very weak. Therefore, when a strong wind blows, a large amount of sand and dust will be swept into the air, forming a sandstorm weather.

The formation of a dust storm requires three necessary conditions: dust matter, high winds, and unstable air conditions.

Sandstorm is a general term for sandstorms and dust storms, which are a sign of desertification. It refers to a disastrous weather phenomenon in which strong winds roll up a large amount of sand and dust from the ground, making the horizontal visibility less than 1 km, and having the characteristics of suddenness and short duration. Among them, sandstorm refers to the sandstorm formed by strong winds blowing a large amount of sand into the near formation; A dust storm is a storm formed by high winds that sweep large amounts of dust and other fine particles into the air.

Sandstorms are divided into 5 levels from light to heavy intensity:

Floating dust: a weather phenomenon in which dust and fine sand float evenly in the air, making the horizontal visibility less than 10 kilometers;

Blowing sand: a weather phenomenon in which the wind blows dust and sand on the ground, making the air quite turbid, and the horizontal visibility is within 1 km to 10 km;

Sandstorm: A weather phenomenon in which strong winds blow a large amount of dust and sand on the ground, making the air very turbid and the horizontal visibility is less than 1 km;

Severe sandstorm: a weather phenomenon in which strong winds blow dust and sand on the ground, blurring and turbidity in the air, and the horizontal visibility is less than 500 meters;

Extremely strong sandstorm: A weather phenomenon in which strong winds blow dust and sand on the ground, making the air particularly turbid and the horizontal visibility is less than 50 meters.

Sandstorm weather is a strong disastrous weather in northwest China and northern China, which can cause house collapse, traffic and power supply obstruction or interruption, fire, human and animal power, etc., pollute the natural environment, destroy crop growth, and cause serious losses and great harm to national economic construction and people's lives and property safety.

Strong wind, strong thermal instability, and sand source are the three important conditions for the formation of sandstorms, respectively.

Favorable weather conditions for the generation of high winds or strong winds, favorable distribution of sand and dust sources and favorable air instability conditions are the main reasons for the formation of sand and dust storms or strong sand and dust storms. Strong wind is the driving force of sandstorms, sand and dust sources are the material basis of sandstorms, and unstable thermal conditions are conducive to the increase of wind and the development of strong convection, so as to entrain more sand and dust, and carry the source to tease and roll the crack base higher.

In addition, the drought and lack of rain in the early stage, the warming weather and the rising temperature are the special weather background formed by sandstorms. The development of convective cells in front of the surface cold front into clouds or squall lines is a small and medium-scale system that is conducive to the development and strengthening of sand and dust storms. The topographic conditions that are conducive to the increase of wind speed, i.e., the narrow pipe action, are one of the favorable conditions for the formation of sandstorms.

1. Sandstorms are formed by the wind blowing up a large amount of sand and dust on the ground and rolling them into the air.

2. First, the sand and dust substances on the ground. It is the material basis for the formation of sandstorms.

3. The second is a strong wind. This is the power basis for the formation of sandstorms, and it is also the power guarantee that sandstorms can be transported over long distances.

4. The third is the unstable air state. This is an important local thermal condition. The frequent occurrence of sandstorms in the late afternoon and evening illustrates the importance of local thermal conditions.

5. Fourth, the arid climate and environment. Dust storms tend to occur in the spring in the north, and the fact that they do not occur for a period of time after the rainfall is good evidence of this.

The specific measures are as follows:

1.We should strengthen the protection of the environment and raise the protection of the environment to the level of the legal system.

2.Afforestation and strengthening of biological protection systems against wind-blown sandstorms. It is necessary to protect and restore forest and grass vegetation in accordance with the law, prevent the further expansion of land desertification, and reduce the source of sand and dust as much as possible.

3.Formulate plans for disaster prevention, disaster resistance, and disaster relief in accordance with local conditions in different regions, actively promote various disaster reduction technologies, and build a number of demonstration projects to gradually promote them from point to point, so as to further improve the regional comprehensive defense system.

4.Control population growth, reduce the pressure of human factors on the land, and protect the environment.