Cultural Connotation of Cold Dew

The cultural connotation of cold dew is as follows:

It is the seventeenth of the twenty-four solar terms, and the fifth solar term in autumn is a festival in late autumn. The beginning of the full moon in lunar calendar is a solar term, which reflects the characteristics of climate change and represents the transition from cool to cold.

Historical origin

Cold dew is the end of the full moon in the dry calendar and the beginning of the full moon. At night, looking up at the starry sky, you will find that the "Big Mars" (Antares) representing midsummer has sunk into the west. After the cold dew, the height of the sun continued to decrease and the temperature gradually decreased. Cold dew is called "cold dew" because the temperature is much lower than that of Bailu solar terms, and cold produces dew condensation.

"Twenty-four solar terms" said: "In September, the dew is cold and will condense." At this time, the temperature is lower than when it is "white dew", with more dew and chill day and night.

Meteorological change

Cold dew is a solar term reflecting the characteristics of climate change. After the cold dew solar terms, the days become shorter, the nights become longer, the sunshine decreases, the hot air slowly recedes, the cold gradually increases, the temperature difference between day and night is larger, and it feels a little chilly in the morning and evening.

After the cold dew, the cold air in the north has a certain influence, and most parts of China are controlled by cold high pressure, and the rainy season is over. Wan Li is clear, warm during the day and cool at night. Thunderstorms have disappeared in most parts of Chinese mainland.

Phenological phenomenon

Wu Cheng, a scholar in Yuan Dynasty, compiled Twenty-four Solar Terms, which divided the cold dew into three stages: first, waiting for Hongyan visitors; Second, the sparrow enters the water and becomes a clam; Three chrysanthemums have yellow flowers. It means that in this solar term, geese move south in a line or herringbone queue; It's very cold in late autumn, and all the birds are gone.

The ancients saw a lot of clams suddenly appearing on the seashore. The stripes and colors of shells were very similar to those of birds, and they thought they were birds. "Chrysanthemum has yellow flowers" means that the chrysanthemum is already in full bloom at this time.

rural activity

After the cold dew, if there is strong cold air going south, the cold dew wind weather with low temperature and strong wind is easy to appear in the south. Cold dew wind is a chilling injury caused by the invasion of cold air in autumn, which reduces rice production.

It is one of the main meteorological disasters in the growth period of late rice in southern China, which mostly occurs around the cold dew festival in the southern lunar calendar. Therefore, Guangdong, Guangxi and Fujian are called cold dew wind, and the Yangtze River basin is called autumn low temperature.