How to solve sandstorm weather in Beijing and other places with dialectics of nature?

Beijing is one of the high incidence areas of sandstorm activities and sandstorms. The so-called sandstorm activity is a series of physical phenomena caused by strong winds acting on the dry surface. Usually, fine dust flies into the atmosphere and is in a suspended state, which is affected by the spatial movement of the atmosphere. Dust moves to tens of kilometers, hundreds of kilometers, thousands of kilometers and tens of thousands of kilometers by means of high-altitude airflow. According to the results of satellite remote sensing monitoring, dust from the Asian continent can cross the Pacific Ocean and reach the central part of the United States. Slightly larger sand grains jump on the ground, while coarse sand grains can't jump and can only roll on the ground. The movement of dust is simultaneous, which often gives people a dark feeling.

The reason of sandstorm weather in Beijing: Beijing belongs to the piedmont alluvial fan. In the Quaternary geological period, the mountainous areas around Beijing were once covered with ice shells. Later, due to the warming of the atmosphere, the ice shell melted and cracked, and huge ice cubes slipped down the slope under the action of running water. This is how the Quaternary glacial scratches in Mosikou, Shijingshan District and the glacier boulders in badachu park were produced. Glacier floods on the mountain push a lot of sediment and gravel down the mountain, forming an alluvial fan, which is located in the urban and suburban areas of Beijing. According to the principle of sedimentology, relatively large individual gravels are deposited first, and then coarse sand, medium sand, fine sand, silt and soil are deposited. Because of this, sand and gravel can often be seen at 8- 10 meters underground in Beijing. In places close to the mountains, such as Shijingshan District, you can see the gravel by peeling off the thin topsoil. Because the underground sand in the urban area is deeply buried, it can only be seen when the infrastructure is dug. Sand will be exposed to the ground in major constructions such as repairing subways and building tall buildings. The sand on the construction site will fly and spread under the action of strong wind. In recent years, Beijing has engaged in infrastructure construction with more than 1,000 construction sites, which is also one of the important reasons for the frequent sandstorms in Beijing in recent years. The windy or windy weather, drought and lack of rain and high temperature in northern China every spring are one of the necessary conditions for sandstorms. In a sense, sandstorms in Beijing seem irresistible. In addition, cultivated land and garbage dumps in the suburbs of Beijing will also raise dust when the wind is strong in spring, which will become an important source of dust in Beijing. The number of cars in Beijing is increasing year by year. Automobile exhaust contains carbon particles that can't be completely burned, and it also increases inhalable particles in the air. Industrial boilers and domestic coal burning will also produce coal ash, which will become a source of dust.

Sunspot theory:

Professor Chen Guangting thinks that there may be accidental factors such as the coming of sunspot activity cycle and abnormal airflow, and there are still many puzzles in the research field at present. Undeniably, in the early 1990s, the phenomenon of land desertification in northern China was very prominent. Grassland degradation and desertification in Inner Mongolia and land degradation in the farming-pastoral ecotone in Hebei are extremely serious. Coupled with 1999 drought in northern China, the surface soil was dry and loose, and the internal injuries with low coverage rate were delayed until the spring of 2000. The dusty weather in Beijing is also related to the geographical and geomorphological features. Professor Zhao Tingning said: Beijing Plain is only about 50 meters above sea level, Badaling area is about 800 meters above sea level, while Bashang area in Zhangjiakou, Hebei Province is over 1000 meters. This "downhill" terrain, coupled with the "narrow tube effect" in the valley area, is easy to make the northwest cold air mass wrapped in dust slow down and stagnate after it comes to Beijing along the tuyere.

Since 2000, the study of sandstorm has also become a focus of academic attention. One of the most controversial issues is where the source of sandstorms in Beijing is. According to Professor Zhao, there is a view that "sand should be raised on the spot", and the "three rivers and two beaches" represented by Yongding River, Chaobai River, Dasha River Basin and Nankou area are the main sandstorm hazard areas in Beijing. Another view is that the sandstorm that has become a big climate still comes from the deserts of Mongolia and other countries abroad, the deserts and sandy land in northwest China, and the aeolian desertification of degraded and desertified land in the farming-pastoral ecotone in this area.

There are three main sand sources affecting Beijing: Mu Us and Kubuqi Desert, Wulanbuhe Sandy Land and Hunshandake Sandy Land.

The first path is Shandake Sandy Land in Inner Mongolia-Heihe River Basin in Hebei-Beijing area;

The second path is Zhu Rihe in Inner Mongolia-Yanghe River Basin in Hebei-Yongding River Basin in Beijing;

The third path is the Sanggan River Basin in Hebei Province-Yongding River Basin in Beijing.

Beijing is located in the northeast of North China, at the southern foot of Yanshan Mountain and east of Taihang Mountain. Mainly composed of loess and sandy land, there is no large area of desert. The desert in northwest China is dominated by sand, which is not the source of dust. Moreover, there is a "Yanshan Taihang" mountain range as a barrier in North China, and the desert is not a concern. What's more, the dust structure in Beijing is very different from the sandy structure in the northwest desert. So the first route seems to have little effect on this.