Autumn and Autumnal Equinox are two different festivals.

1, the time is different

The time of the beginning of autumn is: the sun reaches 135 degrees of yellow longitude on August 6~9 every year.

Autumn, is the lunar calendar twenty-four seasons in the thirteenth season, but also the first season of autumn, marking the official start of the Mengqiu season: "Autumn" means that the summer is cool. At the beginning of autumn, the sycamore tree starts to lose its leaves, hence the idiom of "Fallen Leaves Know Autumn". From a literal point of view, the character "秋" (autumn) is composed of the characters 禾 (grass) and 火 (fire), meaning the ripening of grain. Autumn is the transitional season when the weather changes from hot to cool and then from cool to cold.

The Autumn Equinox occurs when the sun reaches 180 degrees of the yellow meridian on September 22-24 every year.

Autumn equinox, the 16th of the 24 solar terms in the lunar calendar, is generally September 22~24 every year. The climate in the south only begins to fall from this festival. First, the sun reaches 180 degrees of yellow longitude on this day, shooting directly at the Earth's equator, so the vast majority of the Earth's 24-hour day and night in this day, each 12 hours.

2, different characteristics of the festival

Autumn festival climate characteristics

"Autumn" to, but not the fall climate has arrived. Dividing the climate season is based on the "average temperature", i.e., the average temperature of the local area for five consecutive days is below 22 ℃, and only then is it considered to be the real autumn season. China's vast territory, although the climate varies from place to place, but at this time most of the region has not yet entered the fall climate, and every year, the end of the three hot days of ambush is still in the third day of autumn.

Particularly in southern China, this season is still the summer heat, but also due to the typhoon and rainy season gradually gone, the temperature is hotter, so Chinese medicine from the beginning of autumn to the autumn equinox of this period of time is called "long summer". The earliest autumn in Heilongjiang and northern Xinjiang will be in mid-August, and in a typical year, the capital, Beijing, starts to enjoy the autumn breeze in early September, and the Qinhuai area starts to enjoy the autumn from mid-September.

Autumn equinox climate characteristics

Autumn equinox after the sun's direct position moved to the southern hemisphere, the northern hemisphere is getting less and less solar radiation, while the ground to lose more heat, the rate of temperature reduction is significantly accelerated. The "autumnal equinox" is exactly halfway through the 90-day period from the beginning of autumn to the end of frost.

From the day of the autumnal equinox, the climate mainly presents three major features: the location of direct sunlight continues to move from the equator to the southern hemisphere, the northern hemisphere will become more and more pronounced phenomenon of shorter days and longer nights, the day gradually becomes shorter, the darkness becomes longer (until the winter solstice day to reach the darkness of the longest night, the day is the shortest); the day and night temperature difference gradually increase, the amplitude will be higher than 10 ℃ or more; the temperature is declining day by day, day by day, the day is colder than the day, and gradually stepped into the late fall season. The situation in the southern hemisphere is just the opposite.

Expanded information:

China's ancient times will be divided into three waiting for the beginning of the fall: "one waiting for the arrival of cool winds; the second waiting for the birth of the white dew; the third waiting for the chilling cicadas. " Cool wind to: windy people will feel cool, this time the wind has been different from the hot wind in the summer days. White Dew Drops: There will be fog on the ground in the morning. Cicadas chirping: the cold cicadas that chirp in the fall when they feel the shade also begin to chirp.

According to the standard of the average temperature of the climate to divide the season, it must be the average temperature of five consecutive days below 22 ℃ to be regarded as autumn, according to such a standard, the Jianghuai area is generally in the middle and late September before entering the fall. After the fall, although it is difficult to eliminate the heat, although there is a "fall tiger" aftermath, but the general trend is that the weather is gradually cooler. The temperature of the day difference is gradually obvious, often very hot during the day, while the night is relatively cool. In addition, the meaning of autumn is that the crops are ripening.

In fact, according to the climatology of the seasonal standard, the second half of the average daily temperature steadily dropped to 22 ℃ below the beginning of autumn, in addition to the long winter and spring and autumn connected to the summer area, China rarely in the "autumn" on the fall of the region.

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