How are the four seasons divided?

Spring, summer, autumn and winter last for three months, and all the year round is formed because the earth revolves around the sun. The traditional method of dividing the four seasons in China is based on the change of astronomical phenomena, with the "four stands" in the 24 solar terms as the starting point of the four seasons.

At present, the four seasons are usually divided according to the temperature change, which is based on the "average climate temperature" of modern scholar Zhang Baokun. According to this standard, the mid-latitude seasons are basically consistent with the "climate average temperature", and the temperature changes in low latitude areas and near the polar regions are not obvious.

In the southern hemisphere, the time of each season is just the opposite of that in the northern hemisphere. It is summer in the southern hemisphere and winter in the northern hemisphere; It is winter in the southern hemisphere and summer in the northern hemisphere.

Extended data:

Seasonal change covers many characteristics such as climate change and phenological change, such as spring germination, summer prosperity, autumn harvest and winter storage, which indicates the development process of things.

The division of the four seasons is based on the apparent position of the sun on the ecliptic, with the bisector, the second solstice or the fourth day as the boundary; However, the dividing points used by eastern and western countries to divide the four seasons are not exactly the same.

The traditional method of dividing the four seasons in China takes the "four stands" in the 24 solar terms as the starting point of the four seasons, and the dichotomy and the two-to-one method as the midpoint. For example, in spring, the starting point is beginning of spring, the solar line is 3 15, the spring is divided into the midpoint, the long summer is the end point, the solar line becomes 45, and the sun runs 90 on the ecliptic.