The meaning and symbol of slight cold solar terms

The meaning and symbol of the slight cold solar term: starting to enter the coldest day of the year.

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 calendar and the beginning of the ugly month. The meridian of the sun is 285; Every year on the 5th to 7th day of the Gregorian calendar (65438+1October), cold air accumulates for a long time, and slight cold means that the weather is cold but not extreme. Like severe cold, mild summer heat, severe summer heat and intense summer heat, they are all solar terms indicating temperature changes. Slight cold solar terms are characterized by cold, but not extreme.

In 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 dissipation. 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, the 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 in a year. There is a folk saying that "it's 239 when it's a slight cold, and it's almost freezing with cold", which shows that it's a slight cold.

Meteorological change

The weather characteristics of slight cold are: the weather is getting cold, but it is not very cold. In 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. According to China's long-term meteorological records, the solar terms of slight cold are colder than the severe cold in the northern region. But for most parts of the south, the big cold solar terms are colder than the small ones.

Among the slight cold solar terms, the East Asian trough is the strongest and most stable, the Mongolian cold high and Aleutian low are also the strongest and most stable, and the ridge scale of the westerly trough is the largest. The intensity of the west wind is the strongest, and the cooling process of cold air in the slight cold season is frequent, but not many of them reach the cold wave standard.