What does the summer solstice mean in the twenty-four solar terms?

The arrival of summer solstice represents the approach of heat, accompanied by heavy rain, plum rain, high temperature and other climatic characteristics. Before the arrival of the summer solstice, farmers' friends should take preventive measures to prevent the summer solstice climate from damaging crops!

Then, let's see with me what the summer solstice in the 24 solar terms means!

The summer solstice solar term is the tenth solar term among the twenty-four solar terms, and the summer solstice solar term is the first solar term to be determined. In the 7th century BC, the shadow of the sun was measured by civil soil gauge, thus the summer solstice was determined. The summer solstice is June 2 1 or 22 every year.

"However, the summer solstice is not hot." "The summer solstice is already three years old." Although the summer solstice indicates that the hot summer has arrived, it is not the hottest time. After the summer solstice, the temperature will continue to rise for some time, and about twenty or thirty days is the hottest weather.

According to "Zunxian Manuscript", "The sun arrives in the north, the days are long and the shadows are short, so it is called the summer solstice. At best, it is excellent. " On the day of summer solstice, the sun directly reaches the northernmost point of the year, almost directly to the Tropic of Cancer (23 26' north latitude), and the daytime in the northern hemisphere is the longest, and the farther north it is, the longer it is. For example, the daily length of Haikou in Hainan is a little more than 13 hours, Hangzhou is 14 hours, Beijing is about 15 hours, and Mohe in Heilongjiang can reach 17 hours. From summer to the future, the position of direct sunlight on the ground gradually moves southward, and the daytime in the northern hemisphere is shortened day by day. There is a folk proverb that "eating noodles on the solstice in summer will shorten the day". At this time, the southern hemisphere is in the middle of winter.

In ancient China, the summer solstice was divided into three phases: "the first phase of antlers decomposition; Second, wait for cicadas to start singing; Third-class Pinellia ternata. " Although Mi and Lu belong to the same family, the ancients thought they belonged to Yin and Yang. The deer's horn faces forward, so it belongs to Yang. On the solstice of summer, Yin Qi was born, and Yang Qi began to decline, so the front antlers began to fall off. Because mi belongs to yin, it falls in the corner of winter; After the solstice of summer, the male cicada fluttered and sang because of Yin Qi's feeling; Pinellia ternata is a shade-loving herb, named after it was born in swamps or paddy fields in midsummer. It can be seen that in the hot summer, some yin-loving creatures began to appear, while positive creatures began to decline.

China folks divide 15 days from summer to the future into three "hours", usually the first three days, the middle five days and the last seven days. During this period, the temperature in most parts of China was high, the sunshine was sufficient, the crops grew rapidly, and the physiological and ecological water demand was high. At this time, the precipitation has a great influence on agricultural output, and there is a saying that "raindrops are worth tens of millions in summer solstice". In general, the precipitation in the middle and lower reaches of the Yangtze River and Huanghuai area can generally meet the requirements of crop growth. The Chronicle of Jingchu's Age says: "It rained on June 3rd, and the Tian family thought it was sweet, and the whole city congratulated each other." It can be seen that as early as 1000 years ago, people had a clear understanding of the characteristics of this rainfall.