How are the four seasons divided?

The four seasons in a year can be divided as follows:

1, astronomical division

From the astronomical phenomenon, the change of four seasons is the seasonal change of the length of day and night and the height of the sun. In a year, the season with the longest day and the highest sun height is summer, the season with the shortest day and the lowest sun height is winter, and the transitional season between winter and summer is spring and autumn. Therefore, the astronomical division of the four seasons is based on the vernal equinox (March 2 1), summer solstice (June 2 1), autumn equinox (September 2 1) and winter solstice (February 2 1).

2. Meteorological zoning method

In meteorological departments, March-May is usually spring, June-August is summer, September-1 65438+1October is autumn, 65438+2- February is winter, and1,4, 7,1the following year.

3. Ancient division

Take beginning of spring (February 4th or 5th) as beginning of spring, Changxia (May 5th or 6th) as long summer, beginning of autumn (August 7th or 8th) as beginning of autumn and beginning of winter (165438+1October 8th or 9th) as beginning of winter.

4, the lunar calendar division method

In our country, it is customary to divide the four seasons by lunar month. Lunar calendar1~ March is spring, April-June is summer, July-September is autumn, and 10 ~ 12 is winter. The first day of the first month is the first day of the year and the first day of spring, so it is also called the Spring Festival.

Extended data

Refers to the four alternate seasons in a year, namely, spring, summer, autumn and winter. Astronomically speaking, the division of the four seasons is determined by the orbital position of the earth around the sun.

When the earth is in different positions in the orbit of revolution at different times of the year, different places on the earth receive different sunlight and different heat from the sun, which leads to seasonal changes and differences between cold and hot.

The four seasons on the earth are not only periodic changes in temperature, but also periodic changes in the length of day and night and the height of the sun. It affects or determines the movement rhythm of many things in the earth's environment, especially the adaptation of creatures.

reference data

Baidu encyclopedia-four seasons