The daytime from winter solstice is half that of winter, with the shortest sunshine time, and the heat absorbed by the ground is less than the heat lost. After the winter solstice, it begins to count nine, and nine days is a "nine". Before and after March 9th, the heat accumulated on the ground was the least, and the weather was the coldest, so it was said that it was cold on March 9th, and it was already January and February in the summer calendar, and most parts of our country had entered spring, so it was sunny on September 9th.

Generally speaking, the beginning of the winter solstice means that winter is over half, and many places are about to enter the coldest time, but there are not many days left. After half a period of time, the temperature will slowly rise and the weather will slowly warm up.

Extended data:

Winter solstice diet

1, longan boiled eggs; The winter solstice is a big festival in ancient times, and Jiaxing emphasizes the winter solstice. As the saying goes, "the solstice in winter is as big as a year", and the ancient style is preserved. According to the Records of Jiaxing Prefecture (Volume 34: Customs), "The winter solstice is celebrated first, and it is like a New Year's Day ceremony". Folk advocates winter solstice tonic, including red bean glutinous rice and ginseng soup; Tremella, stewed walnuts, longan boiled eggs, etc.

2. Pumpkin pie; After the winter solstice, people in Hefei will eat pumpkin pie on the winter solstice, and the streets and alleys are filled with the fragrance of pumpkin pie. There is also a proverb called "Eating noodles on the winter solstice will make the day longer", which means that after the winter solstice, the night will be shorter and the day will be longer.