What is the cause of sandstorm?

Sandstorm is mainly composed of three factors: first, the conditions that produce strong winds; Second, the factors causing strong vertical instability in the lower troposphere; Third, there are abundant dust sources in the local geographical environment. There are two major sandstorm-prone areas in China: the first is in the northwest, mainly concentrated in three areas, namely, the surrounding area of Tarim Basin, Turpan-Hami Basin passing through Hexi Corridor, Ningxia Plain to northern Shaanxi, Alashan Plateau in Inner Mongolia, Hetao Plain and Ordos Plateau; The second frequent area is in North China, which directly affects the security of the capital Beijing. The sandstorm in China is getting more and more serious, which is mainly caused by unreasonable land development and unreasonable farming. With the increase of population and inadequate management, a large amount of land in northwest and north China has been reclaimed, grasslands have been overgrazed, and natural vegetation has been destroyed artificially, resulting in a large number of bare and loose land, which provides a large number of dust sources for the occurrence of sandstorms. Once a strong wind occurs, it will affect society and endanger people's health.