What does floating dust mean?

Floating dust: the phenomenon that dust and fine sand float evenly in the air, making the horizontal visibility less than 10000 meters.

It belongs to a dusty weather, which mostly occurs in spring and is divided into three grades: floating dust, sand blowing and sandstorm. Floating dust is the weakest category in dusty weather. Floating dust weather, that is, the lowest intensity sandstorm, is a weather phenomenon formed by the generation and transmission of long-distance sandstorms or local sand blowing weather. The strength is weakened, and after the coarse particles in the dust settle by gravity, the fine particles are continuously transported and float in the air. When the wind speed continues to decrease, the suspended dust particles will settle to the ground, so it is commonly known as "falling yellow sand". In dusty weather, distant objects are khaki, the sun is pale or yellowish, and there is no wind or the wind force is ≤3. Dust floats in the air to make the air turbid, and the horizontal visibility is less than 10km. It usually appears before and after the cold air passes through the border. Floating dust and falling dust worsen the surrounding environment and have an important impact on human health, especially the respiratory system.

. Hazard: A large amount of fine sand floats in the air in dusty weather, causing serious air pollution. When the wind speed decreases, floating dust will fall to the ground, forming accumulated dust. If it rains at the same time, it will form "mud rain" It affects flowers and plants and worsens the surrounding environment. In dusty weather, people's eyes, nose, throat, skin and other direct contact parts will be damaged to a certain extent, mainly manifested as runny nose, tears, cough, expectoration and other irritating symptoms and allergic reactions, which can seriously lead to skin inflammation and conjunctivitis.

Go out as little as possible in dusty weather, and close the doors and windows at home in time, especially for patients with chronic bronchitis and families of the elderly and children with relatively weak resistance. On the one hand, floating dust weather is caused by dust accumulation in arid areas, on the other hand, strong winds and thermal instability are prone to occur in winter and spring there. Therefore, the prevention and control of floating dust weather should first strengthen afforestation in arid areas, improve vegetation and strive for soil and water conservation. The second is to strengthen windbreak measures, such as the construction and maintenance of windbreaks.

In addition, it is necessary to strengthen the forecast of strong winds, sandstorms and floating dust, and help the areas and people who may be affected to prepare for it.