Is the cold dew late autumn or late autumn?

Cold dew is the late autumn season in the dry calendar and the beginning of the full moon. There is a proverb in China called "Dew first turns white and then cold", which means that after the dew festival, the dew turns from a little coolness in early autumn to a little coolness in late autumn.

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. This means that in this solar term, geese move southward in a word or herringbone queue; In the cold late autumn, all the birds disappeared. The ancients saw a large number 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 blooms in yellow, indicating that chrysanthemum is already in full bloom at this time.

Climatic characteristics of cold dew

1, the temperature drops gradually.

After entering the cold dew solar term, the temperature gradually cooled down. Especially in the morning and evening, the temperature is more obvious. This has a lot to do with the angle and height at which the sun forms. With the decrease of solar angle, the ground gets less and less solar radiation, and the temperature will naturally drop gradually.

2. The air pressure is high.

In the cold dew solar term, due to the vertical development of cold air and the influence of dry cold air going south, the air pressure is generally high. At the same time, because of this air pressure, the temperature difference between day and night has also increased.

3. The air humidity is rising gradually.

Before the cold dew solar term, the local humidity was relatively low. When the solar term was transferred, with the gradual decline of the temperature, the water vapor in the air gradually increased and the air became relatively humid.

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