What is the origin and custom of "light snow" in the twelve solar terms in China?

From light snow solar terms to light snow, the 24 solar terms indicates the beginning time and degree of snowfall. Entering the light snow solar term means that the temperature continues to fall, the weather is cold, and the precipitation state changes from rain to snow. Light snow, like solar terms such as rain and Grain Rain, is a solar term reflecting precipitation, which is different from what we call light snow with less snowfall every day. If the white dew, cold dew and first frost in the previous solar terms were condensed into water droplets and developed into frost due to the drop in temperature, then the light snow was condensed into snow when the cold dropped below zero. From the change of the names of solar terms, we can see the law of ancient people's activities-observing destiny and arranging life and farming with the change of solar terms. The meaning of light snow solar term "light snow" is a festival that reflects weather phenomena. There is little snow, and there is no snow on the ground. This is the original meaning of the solar term "light snow". The ancient book "Qunfangpu" says: "Light snow will snow when it is cold, and it will not even snow on the ground, and the snow is not big." In other words, due to the cold weather, the form of precipitation changed from rain to snow in the "light snow" festival, but at this time, because the ground is not very cold, the number of snows is small and the amount of snow is not large, so it is called light snow. So light snow indicates the beginning time and degree of snowfall. Light snow, like rain and Grain Rain, is a solar term that directly reflects precipitation. After the light snow festival in the northern region, fruit farmers began to prune the fruit trees and wrap the stems with straw foil to prevent them from freezing. In winter, vegetables are mostly stored in soil, either in the cellar or buried in the soil, which is convenient for eating. As the saying goes, "snow shovel cabbage, snow shovel spinach." When storing Chinese cabbage in deep ditch soil, stop watering about ten days before harvest, do a good job of antifreeze to facilitate storage, and try to harvest it in sunny days. After harvesting Chinese cabbage, the roots of Chinese cabbage are dried in the sun for 3-4 days, and then stored after the outer leaves of Chinese cabbage become soft. The depth of this ditch depends on the height of cabbage. When stored, the roots of cabbage are all downward, and they are discharged side by side in the ditch. When it is cold, cabbage leaves and corn stalks are covered to prevent freezing. However, when storing semi-ripe cabbage, put some water in the ditch and put soil at the same time. The depth of soil and water should be buried in the roots, and it will grow and mature after eating. Light snow solar terms, the northern part of the southern region began to enter winter. "There is no rain in the lotus, but there are frost branches in the chrysanthemum", which has already shown the scene of early winter. Due to the barrier of Qinling Mountain and Daba Mountain in the north, the invasion of cold air is blocked and the severity of cold wave is reduced. The "warm winter" in South China is remarkable. The number of snowfall days in the whole year is mostly less than 5 days, which is much less than that in the middle and lower reaches of the Yangtze River at the same latitude. There is little chance of snowfall before the heavy snow. Even in the middle of winter, you can rarely see the charming scenery of "blowing open the petals of ten thousand pear trees". Because the surface temperature in South China is often above 0℃ in winter, it is more difficult to snow than to snow. Occasionally, although the sky is buzzing, there is no "broken jade" on the ground. In the cold northwest plateau, it usually begins to snow all the year round 10. The number of snowfall days in the northwest of the plateau can reach more than 60 days a year, and snowfall is possible in some alpine regions all year round. After the light snow festival, the temperature plummeted and the weather became dry, which is a good time to process bacon. After the light snow festival, some farmers began to make sausages and bacon and enjoy food during the Spring Festival. Some places in the south also have the custom of eating Ciba in October of the lunar calendar. In ancient times, Ciba was a traditional festival sacrifice in the south of China, which was originally used by farmers to worship the cow god. There is a saying that "in October, Ciba Shao" refers to sacrificial events.