Will the twenty-four solar terms change in the future with climate change?

In fact, strictly speaking, the twenty-four solar terms correspond to the Gregorian calendar, not the lunar calendar. As we all know, "June 21st in the first half of the year and August 23rd in the second half of the year" actually means that the twenty-four solar terms fall on the 6th and 21st of the Gregorian calendar respectively in the first half of the year, and on the 8th and 23rd of the Gregorian calendar in the second half of the year. The difference is one to two days at most. There is no corresponding fixed time between the lunar calendar and the twenty-four solar terms, but there is also a rule: each solar term falls in a fixed lunar month: rain in the first month, vernal equinox in February, grain rain in March, full moon in April, summer solstice in May, and June. Summer heat in July, autumnal equinox in August, early frost in September, light snow in October, winter solstice in November, and severe cold in the twelfth lunar month (in 2033, the autumnal equinox is in September, light snow is in November, and rain is in the twelfth lunar month in 2034). If there is no neutral equinox this month, set a leap month (for example, there will be no neutral autumnal equinox in August of the lunar calendar in 2033).

The twenty-four solar terms of the lunar calendar originated from the Yellow River Basin, which means that the twenty-four solar terms are applicable to the Yellow River Basin. For example, during the light snow solar term, the Yellow River Basin basically has the first snow during the light snow solar term, while the Northeast region with higher latitudes usually has the first snow in mid-to-late October, while the first snow in the Yangtze River Basin generally has to wait until December. There will be no snow in Guangdong, Guangxi, Hainan, and southern Yunnan in the middle and late periods, or even for several years. Even today in the Yellow River Basin where the twenty-four solar terms originated, the twenty-four solar terms are still applicable. They can not only tell people how the weather changes, but also effectively guide farming and tell people when to sow and harvest. According to the twenty-four solar terms Farming is almost no problem.

The other 24 solar terms are also derived from astronomical observations. The ancients used the sun's standard to measure the length of shadows. The day with the longest shadow is designated as the winter solstice, the day with the shortest shadow is designated as the summer solstice, and the day with medium shadow length is designated as the vernal or autumnal equinox. And they know that the winter solstice has the longest night and the shortest day, the summer solstice has the longest day and the shortest night, and the spring and autumn equinoxes equally divide day and night. Finally, the twenty-four solar terms also represent a culture. Even if their true value is really lost, we can still remember them through cultural inheritance. For example, when you mention the Qingming Festival, you will think of the poem "There is a lot of rain on the Qingming Festival, and pedestrians on the road want to die." When you mention the Winter Solstice, you will think of eating dumplings.

In general, the twenty-four solar terms are most suitable for the Yellow River Basin. In the Yellow River Basin, the twenty-four solar terms not only reflect the local weather trends throughout the year, but also guide local agricultural production and represent a type of Chinese culture. It’s just that as the climate warms, there may be a danger of failure. Attachment: Each of the 24 solar terms currently queried on the Internet is actually just a moment. It is the specific moment when the sun reaches a certain point in the ecliptic longitude and shines directly on a certain latitude. The real twenty-four solar terms are not only the day when the solar term enters, but also the half month after this day. Each solar term is divided into three periods, and there are 24 solar terms and 72 periods in a year. Therefore, the twenty-four solar terms are composed of astronomical observations plus observations of weather changes and object image changes.