What does the mid-volt solar term mean?

The midsummer solar term refers to the fourth Geng day from summer to the future, which is the second of the three volts, usually 10 days, and some years are 20 days.

Intermediate latency

The time of accommodation is not fixed every year, and the length of accommodation is different, so it is more troublesome to check the almanac. We can simply use the formula of "Xia San Geng" to express the lodging date, that is, from the third Geng day in Xia Hou, the initial lodging is 10 day, the intermediate lodging is 10 day or 20 days, and the final lodging is 10 day.

In ancient China, the method of "recording the date by branches" was popular, and 60 groups of different names matched with 10 heavenly stems and 12 earthly branches were used to record the date for recycling. The day with the word "Geng" is called "Geng Day". The word "Geng" in Geng Day is the seventh word in "A, B, C, D, E, Ji, G, Xin, Ren, Gui" 10 day, and it is repeated every 10 day.

When there are four Geng days between the summer solstice and the beginning of autumn, the middle part is 10 days. If the fifth Geng Day is before beginning of autumn, it will take 20 days to get to Zhongfu, commonly known as the second Zhongfu; If it is after beginning of autumn, the median value is 10 days.

For example, in 2007, the first day of the first lunar month was Gengzi Day, with the time of July 15, Zhongfu Gengshen Day, July 25th, the last Chen Geng Day, and August 14. August 23 is the tenth day of the last day, and then it will fall. With the shortening of sunshine time, the weather is getting cooler every day. 20 13 years, the first day of lodging is July 23rd, and the lunar calendar is June 16, which lasts for 20 days.

Knowledge expansion

Middling, that is, the second volt of "three volts", is the fourth Geng day from summer to the first Geng day after beginning of autumn. The number of midsummer days is long or short, which may be 10 day or 20 days, depending on the date of the third Geng day (first fall) after the summer solstice solar term every year.

The climate of "dog days" is characterized by "high temperature and high humidity", because the southeast wind blows in dog days and the air is humid. It is humid in dog days, and "high temperature and high humidity" is the climate characteristic of southern China.