What are the solar terms in autumn?

The main feature of summer into autumn is the drop in temperature.

The gradual decrease of temperature is one of the main climatic characteristics in autumn in China. China has a vast territory, and the time of autumn varies from place to place, so does the length of autumn. Taking the autumn time in eastern China as an example, combined with the relevant solar terms, the basic situation of autumn cooling is briefly described.

1, beginning of autumn (7, 8 or 9 August Gregorian calendar)

It is the first solar term in autumn, which means that summer has passed and coolness has come. In ancient China, it was usually used as the beginning of autumn. However, before and after the beginning of autumn solar terms, only the north-northeast area in the east of China really entered autumn, and the middle and lower reaches of the Yellow River were only slightly autumn. However, under the control of the subtropical high, the "dog days" in the middle and lower reaches of the Yangtze River and South China have not yet ended, and the "autumn tiger" will continue to wreak havoc for some time, and the weather is still hot.

However, although these places have not yet entered autumn, the maximum temperature during the day may still exceed 35℃, but the temperature difference between day and night has begun to increase, and it is slightly cool in the morning and evening, which is naturally different from the extreme heat in summer (Yang Wanli's "Chasing Cool at Summer Night").

2. beginning of autumn is followed by intense heat (August 23rd or 24th in Gregorian calendar).

"Chu" means termination, which means that the heat is about to pass and the heat will end on this day. Before and after the summer solar term, "leaves fall in Kanto" (In the City by Zhou Heqiu), and the whole northeast enters autumn.

3. Millennium (7 or 8 September in Gregorian calendar)

This is a festival that reflects the change of temperature. When he knew that the dew would be frost tonight (Du Fu's Moonlit Night Remembering Brothers), the weather turned cold and dew began to appear. Before and after the Millennium solar terms, the golden wind sent cool air to the North China Plain.

4. Autumn Equinox (September 7th or 8th in Gregorian calendar)

It means that autumn is equally divided, and day and night are equally long. "There is a harp playing at midnight, and the west wind blows the green vine" (Xu Hun's "Three Songs in Early Autumn (Part I)"), the northern part of the middle and lower reaches of the Yangtze River enters autumn around the autumnal equinox.

5, cold dew (Gregorian calendar 65438+1October 8 or 9)

But the temperature is lower than the Millennium solar terms, and the dew is about to condense into frost. "The dew is cold in Jiujiang at night, and the north wind gives birth to tiny waves" (Li Qunyu's "Falling into a boat"). Before and after the cold dew solar terms, we arrived in Changsha, Nanchang and Hangzhou, which are cool in autumn.

6. The first frost (Gregorian calendar 65438+1October 23rd or 24th).

It means that the weather is getting colder and colder and the first frost appears. This is the last solar term in autumn, which also means that winter is about to begin. "Autumn chrysanthemums welcome frost, while spring vines hinder sunshine" (Song's First Entering Qingyuan Gorge), the autumn wind only blows to Lingnan and Guangdong around the first frost solar terms, but it is quite different from autumn scenery in the north.