Knowledge points of geography sandstorm in senior high school

Sandstorm is the general name of sandstorm and sandstorm, and it is a sign of desertification.

It refers to a disastrous weather phenomenon that strong winds roll up a lot of dust on the ground, making the horizontal visibility less than 1 km. It has the characteristics of suddenness and short duration, low probability and great harm. Among them, sandstorm refers to a sand-laden storm formed by strong wind blowing a large amount of sand near the stratum; Sandstorm is a storm formed by strong winds, which brings a lot of dust and other particles into the sky.

Causes of sandstorm formation

(1) Strong wind conditions; (2) The factors causing strong vertical instability in the lower troposphere; ③ There are abundant dust sources in the local geographical environment.

Morphological characteristics of sandstorm

① The sandstorm wall stands tall.

The sky was dark.

(3) somersault, rush.

4 brilliant.

Sandstorms are graded.

Sandstorm weather can be divided into five categories: floating dust, sand blowing, sandstorm, strong sandstorm and extra-strong sandstorm.

① Floating dust: a weather phenomenon in which dust and fine sand float evenly in the air, making the horizontal visibility less than 10 km; (2) Sand blowing: the wind blows up dust on the ground, making the air quite turbid, and the horizontal visibility is in the range of 1 km to1km; ③ Sandstorm: a weather phenomenon in which strong winds blow up a lot of dust on the ground, making the air very turbid and the horizontal visibility is less than 1 km; ④ Strong sandstorm: a weather phenomenon in which strong winds blow up dust on the ground, making the air fuzzy and turbid, and the horizontal visibility is less than 500 meters; ⑤ Super sandstorm: Strong wind blows up dust on the ground, making the air particularly turbid, and the horizontal visibility is less than 50 meters.