How are sandstorms formed? What's the harm?

The hazards of sandstorms are firstly strong winds and secondly sandstorms. Its impact is mainly reflected in the following aspects: 1. Wind erodes soil, destroys vegetation, and buries farmland. 2. Pollution Air The monitoring network of the State Environmental Protection Administration showed that on the day of the severe sandstorm on March 20, the amount of dust per square meter in Beijing reached 20 grams, and the total suspended particulate matter reached 11,000 micrograms per cubic meter, exceeding the national standard by more than ten times. More than 100 times the normal value. 3. Impact on traffic The main impact of sandstorms on traffic is as follows: First, reduced visibility affects driving and aircraft takeoffs and landings. For example, seven airports in South Korea were forced to close on March 22, and about 70 flights were canceled on March 21. Second, sand and dust bury the roadbed and hinder traffic. According to the Chinese Business Daily, the train from Urumqi to Xi'an was blocked midway due to a sandstorm that buried part of the railway. 4． Affects the use and production of precision instruments. 5． Hazards to human health: The health damage caused by sandstorms is multifaceted. The skin, eyes, nose and lungs are the first parts to be exposed to sand and dust, and suffer the most serious damage. Damage to skin, eyes, nose, throat and other direct contact parts is mainly irritation symptoms and allergic reactions, while pulmonary manifestations are more serious and extensive. Seven years ago, American health scientists first suggested a link between fine pollution particles and deaths from lung disease and heart disease. Australia's "The Age" said that sandstorms caused by wind erosion of the soil are the main culprit causing asthma in 2 million people in the country. 6. Causing weather and climate changes, the impact of this sandstorm not only involves 13 provinces in my country, but also affects South Korea and Japan; a sandstorm originated in Kazakhstan in September 1998, passed through a vast area in northern my country, and passed a large amount of sand and dust It was transported to North America at high altitude; in April 2001, a strong dust storm originating in Mongolia swept across the Pacific Ocean and the continental United States, and finally dissipated over the Atlantic Ocean. Such large-scale dust forms suspended particles at high altitudes, which is enough to affect the weather and climate. Because suspended particles can reflect solar radiation and lower atmospheric temperatures. As suspended particles significantly weaken solar radiation (about 10%), the speed of the earth's water cycle may slow down and the amount of precipitation decreases; suspended particles can also inhibit the formation of clouds, reduce the precipitation rate of clouds, and reduce the earth's water resources. It can be seen that dust may aggravate drought. Take a look at the following statistics to make us realize the urgency of preventing and controlling sandstorms. Across the country, 1,500 kilometers of railways, 30,000 kilometers of roads, and 50,000 kilometers of irrigation canals have been damaged to varying degrees due to wind and sand hazards. In recent years, the annual direct economic losses caused by sandstorms in my country have reached 54 billion yuan, which is equivalent to three times the fiscal revenue of the five northwest provinces and regions in 1996. Scientists have calculated that it would take more than 2,000 years to scrape away 18 centimeters of topsoil on a piece of grass; for example, it would take 49 years to scrape away the same amount of topsoil on corn farming land; and on bare land, it would only take 18 years. April and May are the periods of high incidence of sandstorms in northern my country. Please pay close attention to the weather forecast and be prepared to prevent sandstorms in advance. Sandstorm is a disastrous weather phenomenon in which wind and sand interact. Its formation is inseparably related to the global greenhouse effect, El Ni?o phenomenon, forest decline, vegetation destruction, species extinction, climate abnormalities and other factors. Among them, over-exploitation of natural resources, excessive deforestation, and over-cultivation of land caused by population expansion are the main reasons for frequent sand and dust storms. As a high-intensity sandstorm disaster, sandstorms do not occur in all windy places. Sandstorms are only likely to occur in areas with arid climate and sparse vegetation. In the northwest region of my country, the forest coverage rate is not high, and the poor northwest people still want to make a fortune by digging licorice, nostrils, and mining. These predatory and destructive behaviors have aggravated the sandstorm disaster in this region. Bare land can easily be blown up by strong winds to form sandstorms or even strong sandstorms. There are many harms caused by sandstorms: 1. Death of humans and animals, collapse of buildings, and reduction of agricultural production. Sandstorms are no less harmful to people, animals and buildings than typhoons and tornadoes. In the past five years, my country's northwest region has been hit by sandstorms more than 20 times, causing economic losses of more than 1.2 billion yuan and more than 200 people dead and missing. 2. Air pollution and topsoil loss. There are at least 38 chemical elements in sandstorm dust. Its occurrence greatly increases the concentration of atmospheric solid pollutants, causing long-term and potential harm to the atmospheric environment, soil, and agricultural production in the origin, surrounding areas, and downwind areas. Especially after the meager topsoil on which crops depend is scraped away, the barren land will seriously affect crop yields.

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