Wait online. Bad weather in the desert.

Sandstorm: it is a general term for sandstorm and sandstorm. It refers to a severe sandstorm weather phenomenon in which strong winds blow up a large amount of sand and dust substances on the ground and throw them into the air, making the air particularly turbid and the horizontal visibility less than1000 m.

Danger:

⑴ Strong wind: Strong wind accompanied by dust damages buildings and public facilities, causing human and animal casualties. ⑵ Sand burial: Farmland, channels, cottages, railways, grasslands, etc. are buried by a large number of quicksand in the form of quicksand, especially posing a serious threat to transportation.

⑶ Soil wind erosion: The dust source and affected area of each sandstorm will be harmed by wind erosion in different degrees, and the depth of wind erosion can reach 1 ~ 10 cm. It is estimated that the annual loss of soil fine matter caused by sandstorms in China is as high as 106 ~ 107 tons, most of which are below 10 micron, which seriously damages the land productivity of farmland and grassland in the source area.

⑷ Air pollution: In the source area and influence area of sandstorm, the inhalable particulate matter (TSP) in the atmosphere increases, and air pollution intensifies. Taking 1993 "5.5" sandstorm as an example, the outdoor air TSP concentration in Jinchang, Gansu Province reached 10 16 mg/m3, and the indoor air TSP concentration was 80 mg/m3, exceeding the standard by 40 times. From March to April, 2000, Beijing was affected by sandstorms, and the number of days when the air pollution index reached Grade 4 or above was 10, which also affected many cities in eastern China. From March 24th to 30th, the daily pollution index of Nanjing, Hangzhou and other cities 18 exceeded Grade IV.

The conditions for sandstorms are: first, strong and lasting winds, and second, a lot of loose and dry dust on the surface.

In terms of time, the frequency of sandstorms in spring accounts for nearly half of the whole year, especially in April.

This ppt can refer to:

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In ancient times, the name of sandstorm was "rain soil", which meant that loess was falling in the sky. Tornadoes don't know.

Encounter a sandstorm: get down and climb to a place where you can avoid it.