The meaning of the twenty-four solar terms and the first frost explains what the first frost solar terms mean.

What does the first frost solar term mean? What are the meanings of the twenty-four solar terms and the first frost? The first frost said that the weather was colder and the dew condensed into frost. Because "frost" is a manifestation of cold weather and large temperature difference between day and night, it is named "first frost" to indicate that "the temperature drops suddenly and the temperature difference between day and night is large". The "first frost" solar term reflects that the temperature difference between day and night changes greatly and the weather is getting colder and colder, but it does not mean that it will be "frost" when entering this solar term. In fact, "frost" didn't fall from the sky. The "frost" is the condensation of water vapor on the ground when it meets cold air due to the change of temperature difference. Because first frost is a manifestation of cold weather and large temperature difference between day and night, it is named "first frost", which means that the temperature drops suddenly and the temperature difference between day and night is large. The first frost festival is the transition from yang to Tibet. As the saying goes, "the first frost kills a hundred herbs." After the first frost, the plants gradually lost their vitality and the land was desolate. The ancient book "Twenty-four solar terms" says: "When the frost comes, the yin begins to coagulate." It can be seen that the "first frost" means that the weather gets cold and Yin Qi begins to condense. After the first frost solar terms, cold air often invades, resulting in a sudden drop in temperature, a great change in temperature difference between day and night, and obvious cold in the morning and evening. "The most obvious solar term of the first frost is that the temperature difference between day and night changes greatly. In autumn, the main climate is dry, and the temperature gradually turns cold. The first frost is a solar term reflecting the temperature change. Cold weather begins with the first frost, which is the last solar term in autumn. It is the transition from autumn to winter, which means that winter is coming. After the first frost, the temperature difference between day and night is large, the weather is cold in the morning and evening, hot at noon, and the autumn dryness is obvious. After the first frost, the plants gradually lost their vitality and the land was desolate. From a scientific point of view, the saying that "dew becomes frost" is not accurate. The frozen dew formed by dew freezing is hard small ice beads. Frost refers to the white ice crystals that condense on the ground or objects when the radiation cooling of the ground cools the air close to the ground below the frost point. Frost refers to the phenomenon of crop freezing injury caused by sudden drop of temperature, so frost does not necessarily occur when frost occurs, and frost does not necessarily occur when frost occurs; However, due to the low temperature during frost, if the temperature continues to drop, it will easily lead to frost. The first frost solar term is generally around the Gregorian calendar1October 23rd 10 every year. At this time, the cold air goes south, the weather is getting colder and colder, and it is colder in the south of China in the morning and evening; However, some parts of the north have already entered winter, and the temperature in some areas has dropped below 0 degrees Celsius. For example, the average temperature in the northeast, eastern Inner Mongolia and most parts of the northwest has been below 0 degrees Celsius. Solar term Song, first frost: frost began to fall around the first frost, and some places were busy planting wheat. Sow wheat early and check quickly to ensure that the seedlings are all together and strong. In this festival, people will harvest glutinous rice, and sweet potatoes will be cut, dried and stored fresh. Pick the cotton carefully and the trees. After harvesting in late autumn, it should be done everywhere, and firewood should be returned to the warehouse. Take good care of the melons and vegetables in the greenhouse, water them with topdressing and prevent insects. Green onions and radishes were harvested one after another, and Chinese cabbage also came to help. Hurry up and repair the leaking ring in the open shed so that the livestock will not catch cold. Tie up the livestock and raise the pigs well, and the wheat seedlings will be gnawed away. Catch adult fish and sell them in the market, but lotus root, reed and cattail are busy harvesting. Killing rats together in urban and rural areas not only prevents diseases but also ensures food.