What are the climatic characteristics of winter solstice? What is the impact on agriculture?

During the winter solstice, the sun shines directly near the tropic of Capricorn, and the daytime in the northern hemisphere is the shortest; After that, the position of direct sunlight moved northward and the days became longer. "After the winter, a needle came out, but it crossed the long line". At this time, the cold air in the north is powerful, which indicates that winter is coming and the coldest season is coming. The average daily temperature in the middle and lower reaches of the Yangtze River ranges from 2 degrees to 5 degrees, and the snowfall or rainfall10mm to 30mm. ..