Four seasons in one mountain, ten miles in different days. Can you explain it?

1. "There are four seasons in one mountain, but different days in ten miles" is a true portrayal of Hengduan Mountains, and the reason for this phenomenon is atmospheric circulation.

2. Atmospheric circulation generally refers to the large-scale atmospheric operation phenomenon with world scale, including both average state and instantaneous phenomenon. Its horizontal scale is more than several thousand kilometers, its vertical scale is more than 10km, and its time scale is more than several days. The state of large-scale movement of the atmosphere. In a large area (such as Europe, Asia, hemisphere and the whole world), the average state of atmospheric movement in a long period (such as month, season, year and year) or the changing process of atmospheric movement in a certain period (such as one week and meiyu period) can be called atmospheric circulation.

Thirdly, the atmospheric circulation is mainly manifested in the east-west wind belt, three-circle circulation (Hadley circulation, Ferrer circulation and polar circulation), the stable distribution of the average ridge, the high-altitude jet and the great disturbance of the westerly wind belt. Atmospheric circulation is not only an important mechanism for the exchange of physical quantities such as heat, water vapor and angular momentum, but also an important result of the transportation, balance and transformation of these physical quantities. The uneven distribution of solar radiation on the earth's surface is the driving force of atmospheric circulation.

4. Atmospheric circulation constitutes the basic situation of global atmospheric movement, is the leading factor of global climate characteristics and large-scale weather situation, and is also the background of various scale weather system activities.