When does the season change usually refer to?

When the seasons change, such as spring entering summer and transition from summer to autumn, the change of every two adjacent seasons is called changing seasons.

Seasonal time: spring: March, April and May; Summer: June, July and August; Autumn: September, 65438+ October, 165438+ October; Winter: 65438+February, 65438+ 10 and February.

The four seasons that alternate in a year, namely, spring, summer, autumn and winter, last for three months. All the year round is formed because the earth revolves around the sun.

Division of the four seasons:

I. Tradition4 Legislation

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. The rotation of the four seasons reflects the changing laws of phenology and climate.

Second, the classification of the West

Astronomical classification (that is, western classification) emphasizes the climatic significance of the four seasons, with the vernal equinox of the sun as the starting point of the four seasons, such as spring as the starting point and summer solstice as the end point. These four seasons are one and a half months later than the traditional four seasons in China.