Why is the winter solstice so cold?

In winter, the days and nights are long and the days are short.

In winter solstice, although the sun is low and the days are short, the temperature in winter solstice is not the lowest in meteorology. In fact, because there is still "accumulated heat" on the surface, it is usually not very cold before the winter solstice, and the real cold is after the winter solstice.

Because of the huge climate difference in China, this climatic winter is obviously late for most parts of China. The winter solstice marks the beginning of the cold season, and people begin to count nine to calculate the cold days.

Extended data:

From winter to the future, although the solar altitude angle gradually increases, it is a slow recovery process, and the heat lost every day is still greater than the heat received, showing a situation of "making ends meet". On the day of "March 9 and April 9", the accumulated heat is the least, the temperature is the lowest, and the weather is getting colder and colder. If there is the influence of cold air at this time, the weather will be even colder. After this "cold front", the weather will gradually get warmer.

In the course of historical development, people all over the country have also compiled various proverbs, ballads and jingles according to different climatic conditions, landscape characteristics, agricultural phenology and customs. There are several nine songs all over the country, but the lyrics are slightly different.