How to classify solar terms, except astronomical angle, climatic conditions and phenology.

Reflect the season

Equinox (vernal equinox, autumnal equinox), Erzhi (summer solstice, winter solstice), Li Si (beginning of spring, Changchun, beginning of autumn, beginning of winter).

The vernal equinox and solstice are the turning points of solar height change and seasonal change. The four stands represent the beginning of the four seasons.

Reflect climate characteristics

Hot and cold: The five solar terms of Little Summer, Big Summer, Midsummer, Slight Cold and Great Cold reflect the arrival of the hottest and coldest periods and the changes of cold and heat.

Precipitation: The four solar terms of rain, Grain Rain, light snow and heavy snow indicate the time and intensity of precipitation and snowfall.

In addition, the three solar terms, white dew, cold dew and first frost, indicate the condensation and condensation of water vapor in the lower atmosphere, and also reflect the gradual decline of temperature and the cooling degree of each solar term. After that, the temperature dropped even more, not only exposed to the sun, but also cooled down, but it was not frozen; Finally, when the temperature drops below zero, the water vapor condenses into frost. From the perspective of agricultural production, these three solar terms are concrete and vivid, with their heat meaning greater than their water meaning.

Reflect phenological phenomena

Xiaoman and Miscanthus reflect the maturity and harvest of related crops.

Scaring and Qingming reflect natural phenological phenomena, especially stinging. It uses the first thunder in the sky and the resurrection of underground stingers to tell the news that everything in the world is back to the earth in spring.