The "Lidong" solar term falls on November 7 or 8 every year. In ancient my country, it was customary for people to regard the beginning of winter as the beginning of winter. "Explanation" said: "Li is the beginning of construction", and also said: "Winter is the end and the collection of all things." In fact, our country has a vast territory. Except for the Qinghai-Tibet Plateau area where summer occurs, winter does not all start at the same time on Beginning of Winter
. According to the climatological standard for dividing the four seasons, if the average temperature in the second half of the year drops below 10°C, it is considered winter. Therefore, the saying "the beginning of winter is the beginning of winter" is basically consistent with the climate rules of the Huanghuai region
< p>match. In the northernmost areas of our country, Mohe and the area north of the Daxinganling Mountains, winter has already entered in early September. The capital Beijing also has a winter scene in late October, and the winter in the Yangtze River Basin is about to reach the "light snow" solar term. It really starts before and after.At the beginning of winter, the sun has reached 225° of ecliptic longitude, and the amount of solar radiation received by the northern hemisphere is getting less and less, because at this time, the amount of heat stored on the surface in the summer half of the year is still a certain amount
There is leftover, so it’s generally not too cold. When the weather is clear and windless, there is often warm and comfortable "Indian Spring" weather, which is not only very pleasant
but also very beneficial to the growth of winter crops. However, at this time, the cold air from the north also has strong power, often invading south frequently, sometimes forming strong winds, cooling and cold wave weather accompanied by rain and snow. Judging from the average conditions over many years, November is the month with the most cold waves. Severe cooling, especially abnormally warm and cold weather, has serious adverse effects on people's lives, health and agricultural production. It is very important to pay attention to weather forecasts and take timely measures to protect humans and crops from cold and freezing damage according to weather changes.
Around the beginning of winter, precipitation decreases significantly in most areas of my country. The ground in Northeast China is frozen, and agricultural and forestry crops have entered the overwintering period; the "Three Autumn Festival
" in the Jianghuai region is coming to an end; Jiangnan is busy planting late-crop winter wheat and transplanting rapeseed; while in South China, it is "beginning of winter wheat planting" "It's the right time". At this time, the quality of water conditions is closely related to the seedling growth and overwintering of crops. In North China and the Huanghuai region, when the daily average temperature
drops to about 4℃ and the field soil freezes at night and disappears during the day, they must seize the opportunity to water wheat, vegetables and orchards with winter water to replenish the soil. Insufficient water, improve the field microclimate environment, prevent "drought aids cold", and reduce and avoid the occurrence of freezing damage. In areas south of the Yangtze River and South China, opening "high yield ditches" in fields in a timely manner and clearing ditches for drainage are important measures to prevent winter waterlogging and freezing hazards. In addition, after the beginning of winter, the air generally becomes drier and the soil contains less water. Fire prevention work in forest areas should also be put on the important agenda.