What are the characteristics of the autumnal equinox season?

The characteristics of the autumnal equinox season are as follows:

1. Equinox day and night: During the autumnal equinox, the sun shines directly on the equator, so day and night are equinoxed, with 12 hours each. Day and night are of equal length, giving a sense of balance.

2. Moderate temperature: During the autumnal equinox, the temperature gradually drops, but it is not as cold as cold dew and frost. The climate at this time is mild and pleasant, neither cold nor hot, and people feel very comfortable. This is also the season for outdoor activities and travel.

3. Obvious autumn dryness: Due to the climate characteristics of autumn, the human body is prone to dry mouth, dry skin, dry stool, etc. At this time, you should pay attention to drinking more water, eating more fruits and vegetables, and maintaining indoor humidity to reduce the impact of autumn dryness on the human body.

4. Harvest season: The autumnal equinox is the season for harvesting crops. The fruits of farmers' hard work begin to appear at this time. Grains, fruits, vegetables and other crops are ripe in large quantities, and people are busy picking, storing and selling them.

5. Migratory birds flying south: Autumn is also the season for migratory birds flying south. Many birds fly from the north to the south in search of warmer habitats. This is also a very important part of the ecosystem.

Seasonal changes during the autumnal equinox:

1. Temperature drop: During the autumnal equinox, the temperature gradually decreases. This is due to the gradual southward shift of the direct sun's point, causing the northern hemisphere to receive less solar radiation. At the same time, the shortening of daytime hours and lengthening of nighttime hours also exacerbated the drop in temperature.

2. The temperature difference between day and night increases: During the autumnal equinox, the temperature difference between day and night gradually increases. This is because after the ground absorbs solar radiation during the day, it loses heat more slowly than at night, causing the temperature at night to be lower than during the day. This change in temperature difference can easily lead to meteorological disasters such as frost and low-temperature freezing.

3. Precipitation decreases: During the autumnal equinox, precipitation gradually decreases. This is because the summer monsoon gradually weakens and the winter monsoon gradually strengthens, making it difficult for water vapor to stay in the northern hemisphere for a long time. Therefore, the autumnal equinox is usually a drier season with less rain.

4. Plants change color: During the autumnal equinox, many plants begin to change color. This is because the temperature drops and the sunshine time shortens, causing the chlorophyll in the plants to gradually decrease, while the yellow and red pigments gradually increase. This discoloration is called foliage and adds beautiful color to fall.