The Millennium solar terms have produced a lot of culture and art in the development and transformation. What does a cool night mean?

Bailu is the15th festival among the 24 solar terms in China. The Bailu solar terms have produced many different cultures and arts in the continuous development trend and changes. So what does the white dew mean when it is cool all night? Is the cold dew the beginning or the end of autumn?

What does the white dew mean when it gets cold overnight? In fact, it means that the temperature difference between day and night is getting bigger and colder every day.

Entering the "White Dew", the temperature difference between day and night is very large, and you will feel a little cold at night, obviously feeling that the cool autumn has arrived. In the case of cold dew, summer monsoon is gradually replaced by winter monsoon, strong cold air turns to attack, and the air slowly retreats. Strong cold air enters the south in stages, which usually produces a certain degree of cooling. Everyone likes to use the proverb "cold dew and autumn rain night, cold all night" to describe the acceleration of average cooling rate.

The meaning of this sentence is that after the Millennium solar terms, the autumn wind blows gently and it gets colder every night. Millennium is the fifteenth solar term among the twenty-four solar terms, and autumn is the third solar term, indicating the end of the Qiu Meng season and the beginning of the Mid-Autumn Festival, which is an important festival reflecting the temperature changes in nature. The Millennium is the end of the application of the lunar calendar in the lunar calendar and the beginning of January. The time point is September 7th to 9th every year in Gregorian calendar, and the sun reaches longitude 165 degrees.

Millennium is the solar term with the largest temperature difference between day and night. Before and after the Millennium, the summer heat gradually disappeared, the yin of heaven and earth rose and spread, the weather gradually turned cold, and the dew in the morning became thicker and thicker, condensing into a layer of white water droplets on the surface of grass leaves. The ancients used four seasons with five elements. Autumn is golden yellow and golden white, so it is called "White Dew" because it is white.

According to the observation of nature, the ancients in China divided the Millennium into three stages: "When the geese come, the mysterious birds return, and the birds are ashamed." This means that in this solar term, migratory birds such as Hongyan and Swallow fly south to avoid the cold, and hundreds of birds begin to store dried fruit food for the winter. At present, farmers are also busy harvesting crops. As the saying goes, "If you grab autumn, you will lose it." During the Bailuyuan period, local folk customs mainly included offering sacrifices to Dayu, brewing grain wine and drinking Bailuyuan tea.

Is the Millennium the beginning or the end of autumn? It is neither the beginning nor the end, but the third festival in autumn.

Millennium is the third festival in autumn. The solar terms in autumn include six festivals: Cold Dew, Great Summer, Bailu, beginning of autumn, Winter Solstice and first frost. When the cold dew is cold, the finger is pointing, and the sun's yellow meridian 165 degrees is around September 7 in the solar calendar. Dew is a unique weather phenomenon after the "cold dew" festival. At night in this season, Yin Qi is getting heavier and heavier, and water vapor can be seen everywhere on the crawling weeds, so it is called Millennium. The temperature at this time, as recorded in the Book of Rites: "The cold wind comes, the dew falls, and cicadas sing."

"White Dew" has a large temperature difference between day and night all year round. Generally, the temperature difference between day and night is around 10℃. At this time, the big cyclone has just begun to change from the summer wind direction to the winter wind direction, and the strong cold air in North China has obviously just begun to invade frequently. In addition, the direct sunlight on the road moves south, so the sunshine hours on the map of the northern hemisphere are getting shorter and shorter, and the daytime time is reduced, which leads to the rapid decline of the average temperature.