Phenology of autumnal equinox solar terms

The phenology of the autumnal equinox solar terms is that thunder begins to hear sounds, then insects sting, and finally water dries up.

1, the first thunder stops.

As soon as the thunder stops, it means there is less thunder, because thunderstorms in summer are more frequent than in early autumn, and thunder is very frequent. In the autumn equinox, as the weather gets colder and colder, the warm and humid air is driven away by the cold air in the north. Sunny Wan Li becomes the most important weather at this time, and thunder naturally becomes scarce and there is no rain.

2. The second blank household waiting for insects

Some insects unearthed at the vernal equinox will return to the soil after the autumnal equinox to prepare for winter. In other words, due to the cold weather, dormant insects began to hide in caves and sealed the hole with fine soil to prevent the cold from invading.

3, third-class water dry.

Water vapor is not as abundant as in summer, and it will start to dry up gradually, so people will feel the air is getting drier and drier.

Meteorological changes of autumnal equinox

According to the lunar calendar, "beginning of autumn" is the beginning of autumn and ends with "the first frost". The "vernal equinox" is exactly half of the 90 days from beginning of autumn to the first frost. Since the autumnal equinox, the climate has three main characteristics: the direct sunlight continues to move from the equator to the southern hemisphere, and the phenomenon of short days and long nights in the northern hemisphere will become more and more obvious until the winter solstice reaches the longest night and the shortest day; The temperature difference between day and night gradually increases.

The situation in the southern hemisphere is just the opposite. After the autumnal equinox, the direct sunlight moves south, the days in the northern hemisphere become shorter, the nights become longer, and the temperature drops, which is of universal significance throughout the country.

At the autumnal equinox, the Yangtze River basin and its vast northern areas in China entered the autumn divided by "climatic average temperature" one after another, and the daily average temperature 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.