1. Ancient division method: start with spring, summer as summer, autumn as autumn, and winter as winter.
2, meteorological division method: in the meteorological department, usually the solar calendar March to May for spring, June to August for summer, September to November for autumn, December to February for winter, and often 1, April, July, October as winter, spring, summer, autumn representative months.
3, astronomical division: from the perspective of astronomical phenomena, the change of the 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 transition season between winter and summer is spring and autumn.
4, the lunar calendar division method: China's folk custom to use the lunar month to divide the four seasons. Spring is from January to March, April to June, autumn from July to September, and winter from October to December. The first day of the first lunar month is the first day of the year, and it is also the first day of spring, so it is also called the Spring Festival.
Four seasons refers to the four seasons that alternate during the year, spring, summer, autumn and winter. The four-season phenomenon is an astronomical phenomenon that is not only a cyclical change in temperature, but also a cyclical change in the length of day and night and the height of the sun.
The Earth has two basic movements, one is rotation, which rotates around the earth's axis that passes through the north and south poles, the direction is from west to east, the farther away from the poles, the faster the rotation, and the middle circle at equal distance from the poles is called the equator, and the time for the Earth to rotate for one week is 24 hours.
The other is the rotation, the Earth orbits the sun at a speed of 30 kilometers per second, and it takes 365 days to orbit the sun at 5 hours 48 minutes and 46 seconds, which is astronomically called the year of return.
The Earth's orbit around the Sun is elliptical and at an angle to the plane of rotation. When the earth is in different places in the orbit of the year, the sunlight received by various places on the earth is different, and the heat received by the sun is different, so there are seasonal changes and differences in hot and cold.