The origin and customs of China s 24 solar terms

The origin of the 24 solar terms: In ancient China, the sundial was measured by Tugui, and the longest annual shadow was set as the "winter solstice", and the shortest shadow was the "summer solstice". In spring and autumn, when the length of day and night is equal, it is designated as the "spring equinox" and "autumn equinox".

By the Qin and Han dynasties, the 24 solar terms had been fully established. In 104 B.C., the "Taichu Calendar" formulated by Deng Ping officially set the 24 solar terms in the calendar, clarifying the astronomical position of the 24 solar terms. The custom of the 24 solar terms:

It reflects three types of changes: seasonal changes, temperature changes, and climate changes. It is a supplementary calendar established in ancient China to guide agricultural affairs, and it is the crystallization of the long-term experience and wisdom of the working people of the Han nationality.

The 24 solar terms are: the beginning of spring, rain, stunning, equinox, Qingming, Guyu, Lixia, Xiaoman, mangzhong, summer solstice, small heat, great heat, beginning of autumn, summer heat, white dew, autumn equinox, cold dew, frost, beginning of winter, light snow, heavy snow, winter solstice, small cold, big cold.

The 24 solar terms refer to the 24 seasons and climate, and are a supplementary calendar established in ancient China to guide agricultural affairs.

The traditional East Asian summer calendar (lunar calendar) is a "lunisolar calendar" based on the movement of the day and the month: the part of the month is determined based on the synodic month, and the year is determined based on the return year (solar year). The solar calendar returns to the year about one day, and the twenty-four solar terms are divided accordingly.

Since the main political, economic, cultural and agricultural centers in China were mostly concentrated in the Central Plains of the Yellow River Basin, the 24 solar terms were established based on the climate and phenology of this area.

As early as the Spring and Autumn Period of the Eastern Zhou Dynasty and the Warring States Period, there was a concept of the southern solstice and the northern solstice of the day among the working people of the Han nationality. Subsequently, according to the position of the sun and moon at the beginning of the month and the middle of the month, and natural phenomena such as weather and the growth of animals and plants, people used the relationship between them to divide the year into 24 equal parts. And give each equal part a proper name, which is the twenty-four solar terms.

In the "December Chronicle" of the "Spring and Autumn Period of the Lu Family", which was written in the late Warring States period, there are eight solar terms names, such as the beginning of spring, the spring equinox, the beginning of summer, the summer solstice, the beginning of autumn, the autumn equinox, the beginning of winter, and the winter solstice. These eight solar terms are the most important of the 24 solar terms. The transition of the seasons is marked, and the four seasons of the year are clearly demarcated.

By the Qin and Han dynasties, the 24 solar terms had been fully established.

The origin of the 24 solar terms: The 24 solar terms are formulated by people in ancient times according to the changes in the position of the earth on the ecliptic (that is, the orbit of the earth around the sun), and each solar term corresponds to a certain position reached by the sun every 15 degrees on the ecliptic.

The 24 solar terms take a cycle of the earth's revolution around the sun as a cycle, which basically summarizes the different positions of the sun on the ecliptic at different times of the year, the exact time of cold and summer, the occurrence of natural phenomena such as rain and snowfall, and the time when some phenological phenomena in nature are recorded.

Type of climate

The 24 solar terms are the product of agricultural civilization, which is a knowledge system formed by the ancient ancestors by observing the movement of celestial bodies combined with the laws of geography, climate and phenological changes. Agricultural production is closely related to geographical and climatic resources, and superior geographical and climatic resources are important conditions for the birth of agricultural civilization. China is located in the eastern part of the Eurasian continent and the west coast of the Pacific Ocean, with huge differences in the thermal properties of land and sea, thus forming the most typical monsoon climate in the world.

The monsoon climate is a mixture of continental and oceanic climates. In winter, the weather is cold, dry and rainless, under the influence of dry and cold airflows from the inland; In summer, it is affected by the warm and humid air flow from the ocean, and it is hot, humid and rainy. Abundant sunshine, abundant precipitation, high temperature and humidity rain and heat are very superior climatic resources in China during the same period.

The high temperature period is consistent with the rainy period, and the water and heat are well matched, which is very beneficial to the growth of crops. Climate factors include light, temperature and precipitation, among which precipitation is an important factor in climate. The twenty-four solar terms accurately reflect the law of natural rhythm changes and play an extremely important role in ancient agricultural production.

The origin and meaning of the solar term are as follows:

The 24 solar terms originated in ancient China, and began to be implemented in the Spring and Autumn Period, the 24 solar terms were originally used to guide agricultural production, and linked weather changes and climate change with crop growth, providing a scientific timetable for agricultural production.

There is such a description in Huainanzi: "The Yellow Emperor began to take the first month as the yuan and the standing stone as the standard." The so-called "stand" means to stand up, erect, the first month refers to the first full moon night of the lunar year, that is, the first month, the month that the Chinese attach the most importance to, the so-called beginning of the year.

The "24 solar terms" can reflect the changing laws of natural phenomena and guide people's agricultural production and life.