Twenty-four solar terms are based on the climate in which part of China?

Twenty-four solar terms are formulated according to the climate of the middle and lower reaches of the Yellow River in China.

According to the position of the sun on the ecliptic, the 24 solar terms are divided into 24 seasons and the climate that reflects the natural phenomenon and seasonal characteristics of farming in a certain area of China (represented by the middle and lower reaches of the Yellow River).

Since 2000, the main political activity centers in China have been concentrated in the middle and lower reaches of the Yellow River, and the 24 solar terms have been established on the basis of climate and phenology in this area. Due to the vast territory and changeable terrain of China, the 24 solar terms are only a reference for many regions.