The significance of autumnal equinox

The autumnal equinox means that autumn is over half.

The autumnal equinox is the sixteenth solar term among the twenty-four solar terms and the fourth solar term in autumn. Fight refers to unitary; The sun reaches the yellow meridian180; Celebrated on September 22-24 of the Gregorian calendar every year. On the day of the autumnal equinox, the sun shines almost directly on the equator of the earth, and the length of day and night is equal all over the world. The autumnal equinox symbolizes that autumn has passed halfway. After the autumnal equinox, the position of direct sunlight moves south, and the days in the northern hemisphere become shorter, the nights become longer, the temperature difference between day and night increases, and the temperature drops day by day.

The autumnal equinox used to be the traditional "Moon Festival", and the Mid-Autumn Festival evolved from the "Autumn Moon Festival". On June 2, 2065438, People's Republic of China (PRC) * * and the State Council issued a reply on agreeing to set up "China Farmers Harvest Festival", agreeing to set up the annual autumn equinox as "China Farmers Harvest Festival" from June 20 18.

Meteorological changes of autumnal equinox

In different seasons, China's Yangtze River basin and its vast areas to the north have successively entered the autumn divided by "climatic average temperature", and the daily average temperature has dropped below 22℃. The cold air mass in the north began to have some influence. The rainy season has just ended in most areas, with a cool breeze blowing gently. Autumn is crisp and the sky is high and the clouds are light.

After the autumnal equinox, the direct sunlight moved to the southern hemisphere, and the northern hemisphere got less and less solar radiation, but the ground lost more heat and the temperature dropped significantly. Agricultural proverbs say: "An autumn rain is a cold", "The white dew is divided into autumn nights, and one night is cold".

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