Causes of the four major quasi-stationary fronts in my country

Causes of the four major quasi-stationary fronts in my country:

Quasi-stationary front refers to the phenomenon that the front maintains a relatively fixed position for a long time and has a small range of movement. These four quasi-stationary fronts are mainly distributed in the middle and lower reaches of the Yangtze River, and the reasons for their formation are as follows:

Jianghuai quasi-stationary front: mainly occur in the middle and lower reaches of the Yangtze River, including the Jianghuai and Huanghuai regions. It is mainly formed because the warm and humid air from the south often extends northward to the Yangtze River Basin and the areas north of the Yangtze River in summer, while the cold air from the north is still quite strong. Therefore, the two types of cold and warm air converge in the Yangtze-Huaihe River Basin to form a front.

Because cold air is heavier than warm air, the front tilts southward, and under certain conditions, it may stay in this area to swing.

Kunming quasi-stationary front: also known as Yunnan-Guizhou quasi-stationary front. Located on the Yunnan-Guizhou Plateau, it is mainly formed by the encounter between the degenerated polar continental air mass and the southwest monsoon. The Kunming Stationary Front, also known as the "Yunming Stationary Front", appears over the Yunnan-Guizhou Plateau from July to August. It is a low-air cold high-pressure, and the ground is a low-pressure center.

This front causes the cold and warm air masses from the north and south to stagnate on the Yunnan-Guizhou Plateau. The south and northwest of the front are controlled by warm air masses, and the north and northeast of the front are controlled by cold air masses. However, the temperature difference between the two sides of the front located on the Yunnan-Guizhou Plateau is not large.

Tianshan quasi-stationary front: also known as the Ural Mountains quasi-stationary front. This front is mainly located in Russia, where cold air from Siberia meets warm and moist air from the North Pacific. Because cold air is heavier than warm air, the cold air reaches the Tianshan region not far away when it moves southward, so this front often swings near the Ural Mountains.

Beiping quasi-stationary front: also known as North China quasi-stationary front. This front is mainly distributed in the North China region, including Beijing, Tianjin, Hebei and Shandong. It is formed mainly when cold air from Siberia meets warm and moist air from the Pacific Ocean. Because the cold air moves southward and tends to stagnate near the Taihang Mountains and Yanshan Mountains, this front often swings near the Taihang Mountains and Yanshan Mountains.

The formation and activity of these quasi-stationary fronts are closely related to weather systems, topography and seasonal changes. During their activity, they often bring weather phenomena such as long-term widespread precipitation, continuous rain or snow. Therefore, these quasi-stationary fronts have an important impact on my country's weather and climate.