What are the causes of sandstorms and what are the hazards of sandstorms?

The period between spring and winter is the peak period for sandstorms. During this period, the climate in the north is dry, and with strong winds, sandstorms can be seen everywhere. Sandstorms cause great trouble to our travel. So, how are sandstorms formed? Let's learn about the relevant knowledge with Encyclopedia Knowledge Network!

Contents of this article

1. What causes sandstorms?

2. What are the hazards of sandstorms?

3. What should you do when encountering a sandstorm?

What causes sandstorms?

1. Natural conditions

Due to the weather conditions of strong or heavy winds, favorable distribution of sand and dust sources and favorable unstable air conditions are the main reasons for the formation of sandstorms or severe sandstorms. Strong winds are 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 force and the development of strong convection, thereby entraining more sand and dust and lifting them higher.

2. Physical factors

Under the extremely favorable large-scale environment, high-altitude dry cold jets, strong vertical wind speed, wind direction shear and thermally unstable stratification conditions, small and medium-scale systems are generated and developed near the frontal area, which intensifies the pressure and temperature gradients before and after the frontal area, forming a huge pressure and temperature gradient before and after the frontal area. Under the combined effect of momentum transfer and gradient deviation wind, the wind speed near the ground layer rises sharply, stirring up surface dust and forming sandstorms or severe sandstorm weather.

3. Environmental factors

Thanks to the efforts of experts from the Cold and Arid Regions Environmental and Engineering Research Institute of the Chinese Academy of Sciences, a sandstorm wind tunnel simulation experiment specially set up to explore the initiation and transmission mechanism of sand and dust materials was successfully completed. Through the experiment, experts found that soil wind erosion is the primary link in the occurrence and development of sandstorms. Wind is the most direct driving force for soil, among which the nature of airflow, wind speed, and related conditions of wind force in the process of soil wind erosion are the most important factors. In addition, soil moisture content is also one of the important reasons affecting soil wind erosion.

4. Human factors

The occurrence of sandstorms is not only the product of specific natural environmental conditions, but also has a corresponding relationship with human activities. Overgrazing, deforestation, industrial and mining construction, and especially excessive land reclamation have destroyed ground vegetation, disturbed the ground structure, and formed large areas of desertified land, which directly accelerated the formation and development of sandstorms.

What are the hazards of sandstorms?

1. Environmental pollution

When a sandstorm occurs, the sand and dust carried by the strong wind spread everywhere, and the air in the area passed by became turbid, choking the nose and eyes, and the number of people suffering from respiratory diseases increased. For example, on May 5, 1993, a strong sandstorm occurred in Jinchang City. The dust content in the outdoor air monitored was 1016 mm/cubic centimeter, and the indoor air was 80 mm/cubic centimeter, which was 40 times higher than the national standard for dust content in living areas.

2. Production and life are affected

The large amount of sand and dust carried by sandstorms blocks the sun, making the weather gloomy, resulting in reduced solar radiation and poor visibility for several to more than ten hours, which can easily make people depressed and reduce work and study efficiency. In mild cases, a large number of livestock can suffer from respiratory and gastrointestinal diseases. In severe cases, a large number of "spring fatigue" livestock will die, and fertile soil, seeds and seedlings in farmland will be blown away.

Dust storms can also cause wind erosion of the surface soil, exacerbate desertification, and cover plant leaves with thick dust, affecting normal photosynthesis and causing crop yields to drop. Dust storms can also cause temperatures to drop sharply, with the sky acting as a parasol and the ground in the shadow becoming dark and cold.

3. Loss of life and property

On May 5, 1993, a strong sandstorm occurred in Jinchang City, Wuwei City, Minqin County of Wuwei City, Baiyin City and other cities in Gansu Province, affecting 2.5355 million mu of farmland, destroying 42,800 trees, causing direct economic losses of 236 million yuan, killing 85 people and seriously injuring 153 people.

On April 12, 2000, strong sandstorms hit Yongchang, Jinchang, Wuwei, Minqin and other cities. According to incomplete statistics, the direct economic losses in Jinchang and Wuwei alone reached 15.34 million yuan.

What to do when encountering a sandstorm?

1. Reduce going out and keep indoor humidity

Dust storms usually bring sandstorm weather, so you should try to avoid going out and keep the indoor air moist.

According to experiments, the human body feels most comfortable and is not prone to disease when the air humidity is usually 50%-60%. If the humidity in the house is too low, then measures should be taken to increase the moisture content in the air.

The weather during sandstorms is dry, so families with babies should pay attention to maintaining the humidity in the room. They can use a humidifier or sprinkle water, mop the floor with a wet rag, etc., which can effectively increase the humidity in the room.

At the same time, doors and windows should be closed to prevent dust or particles carrying germs from entering the room. Usually, you can also use sterilizing air fresheners at home, and you can also take isatis root and other products to prevent virus invasion.

2. Wear all your clothes when going out to protect your body from bacteria

When going out, be fully armed, wear a mask, bring windproof glasses, a hat, a scarf, etc.

Choose a dust-proof and dust-filtering mask to reduce the amount of dust and particles inhaled by the human body, wear windproof glasses to reduce the chance of sand and dust entering the eyes. At the same time, ensure that the optical performance of the glasses is good.

If dust accidentally gets into your eyes, avoid rubbing them with your hands to avoid bacterial or viral eye diseases. The correct way is to rinse with clean water and wipe with a wet towel.

In addition, you should wrap your head with a scarf to protect your ears and avoid exposing any body parts directly to the air.

3. Pay attention to traffic safety when driving

In areas affected by sandstorms, horizontal and vertical visibility is only a few hundred meters or tens of meters, so pedestrians and vehicles should pay attention to traffic safety, and pedestrians should try to walk along the sidewalk.

When driving, you should control your speed, turn on your width lights, fog lights, tail lights, and speed, and honk your horn frequently to warn vehicles in front, behind, and on the left and right. Small cars should try to avoid merging lanes to prevent being blown off the road by strong winds. At the same time, you should also pay attention to avoiding large trucks, and stay away from balconies and billboards.