Slight cold is the 23rd solar term among the 24 solar terms, the 5th solar term in winter, the end of the second month of the dry branch calendar and the beginning of the ugly month. Fighting fingers; The solar meridian is 285; On January 5-7 of the Gregorian calendar every year. Cold air is cold for a long time, and slight cold means that the weather is cold but not yet extreme. Like severe cold, slight summer heat, great summer heat and summer heat, it is a solar term indicating the change of temperature. The slight cold solar term is characterized by cold, but it is not extremely cold.
During the slight cold season, the direct point of the sun is still in the southern hemisphere, and the heat in the northern hemisphere is still in a state of loss. The heat absorbed during the day is still less than the heat released at night, so the temperature in the northern hemisphere continues to decrease. After the winter solstice, cold air frequently goes south, and the temperature continues to drop, and the temperature drops to the lowest during the slight cold and severe cold of the year. As the folk saying goes, "It's February 239 when it's a slight cold, and it's freezing cold and shivering", which shows the degree of coldness of the solar terms.
According to the long-term meteorological records in China, the slight cold solar terms are colder than the severe cold solar terms in the north, and there is a saying that "slight cold is better than severe cold" in the north; However, for some areas in the south, the lowest temperature in the whole year will still appear in the great cold solar terms. The slight cold in northern China is colder than the severe cold, because there is relatively little "residual heat" on the surface, which has been completely released by the slight cold to minimize the temperature. However, the surface of the southern region is relatively hot, and its "residual heat" has not been released until the slight cold. When it comes to the severe cold, the surface "residual heat" is exhausted and the temperature is minimized.
