Why is the autumn equinox "thunder start"?丨 Folk Calendar · Twenty -four solar terms

Cover news reporter Zhou Qin

"Golden Qiqiu equinox, wind and cooling during the cold autumn." September 23 will usher in the autumn equinox solar terms. The autumn equinox is divided into autumn. From then on, the northern hemisphere is shorter and shorter during the day and nights.

There are three waiting in the autumn equinox: the first thunderstorm starts; Why do you say that the autumnal point thunder starts? Come to listen to Wang Liwei, a lecturer of the atmospheric science department of Shenyang Agricultural University, to interpret it for you.

Autumn equinox is busy with agriculture (pictured according to Xinhuanet)

Day and night

On the autumnal equinox, the sun is almost direct to the Earth equator, and the day and nights around the world are waiting. The "division" of autumn equinox means equal division. In addition to the division of day and night, it also means more than half of the autumn. After the autumnal equinox, the direct sunlight shifts south, the northern hemisphere is short and long, the temperature difference between day and night increases, and the temperature has begun to decline significantly.

In the autumnal equinox, the Yangtze River Basin and the vast areas north of my country basically have almost entered autumn, and the average daily temperature has dropped below 22 ° C. And at this time the rainy season in most parts of the north has just ended, the sky is clear, the wind and the sun are beautiful, making people feel that the autumn is high. At the beginning of the autumnal equinox, the temperature was relatively high and the physical sensation would be hotter at the beginning of the autumnal equinox. Enjoy the rare good weather in this year.

Thunder

There are three times in the autumn equinox, the thunder is accepted, and the two puppets have been picked up. Wang Li, a lecturer at the Department of Atmospheric Sciences at the Shenyang Agricultural University of Agricultural University, said that when the thunder started to make a sound, there was less thunder, because the thunderstorms in the early autumn were more frequent and the thunder was very frequent. The weather is getting cooler, and the warm and humid air is driven away by the cold air in the north. The clear sky becomes the most important weather at this time. Naturally, the thunder is gradually scarce with the rain without rain. The ancients believed that Lei made a sound because of the strong yang. Therefore, the scarcity of thunder is not only the end of the summer heat, but also the beginning of autumn cold.

Secondly, the word "blank" means thin soil, that is, because the weather becomes cold, the small worm in the house begins to start in the Tibetan hole, and seal the hole with fine soil to prevent the cold from invading the cold. The water began to rise, and the rainfall began to decrease. Due to the dry weather, the water vapor evaporated quickly, so the water in the lake and the river became less, and some swamps and pudding were dried up. In general, the meaning of these three expressions is that the autumnal equinox starts, the weather is getting colder, and the less rain.

Wang Li, a lecturer of the Department of Atmospheric Sciences of Shenyang Agricultural University of Agricultural University, conducted science science courses for elementary school students. Interviewee confidence

At the time of the autumn equinox, Mai Zheng

As soon as the autumnal equinox, the temperature dropped particularly fast, making autumn harvest, autumn farming, and autumn species look particularly busy. Among them, winter wheat has begun to sow in North China. There is a saying that Bai Lulu is early, cold dew, and autumn equinox. Wang Liwei said that the winter wheat should not be prematurely planted, because the premature planting temperature is relatively high, and the wheat has been unplugged and strong before the winter, but the long -term wheat has a weak wintering ability. It's easy to keep it. Starting from Bailu's solar terms, the temperature will be affected by the cold air in batches and start to decline, but it takes some time to change from hot to cool. Therefore, after the white dew solar terms, only the temperature falling in the morning and evening will be obvious. At noon, the temperature is still. Very high. Therefore, the winter wheat is planted in Bailu soil.

After the solar terms of cold dew, it has entered late autumn. The day is short and night, the heat gradually dissipates, the cold is gradually rising, and the temperature has dropped to a very low. Some areas in the north began to enter the winter from the cold dew. Too late, it will affect the seedling rate of winter wheat, and the anti -freezing ability of wheat seedlings is also very poor, resulting in winter wheat cannot overwinter. Therefore, the autumnal equinox is between these two solar terms. The time is just right.

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