The autumnal equinox solar terms are characterized by an increase in rainfall.

The phenomenon that the characteristics of solar terms in autumn equinox lead to the increase of rainfall is mainly determined by the climatic characteristics of autumn equinox.

The autumnal equinox is one of the 24 solar terms and the middle node of autumn. At this time, the sun shines directly on the equator, the time between day and night is equal, and the temperature difference between day and night is large. This unique climatic condition has influenced the change of weather, and then a unique phenomenon of precipitation enhancement has appeared.

At the autumnal equinox, due to the increase of temperature difference between day and night, better atmospheric condensation conditions are formed. At the same time, as the surface temperature drops, the moisture in the atmosphere will also condense into clouds and fog, leading to an increase in precipitation. Therefore, continuous rainy weather or rainstorm weather often occurs in the autumn equinox season, which has a certain impact on people's lives and agricultural production.

In addition, the precipitation in the autumn equinox season is also affected by many factors such as geographical location and climate change. The precipitation in different areas will be different, and some areas may be dry or lack of rain. At the same time, global climate change will also have an impact on the autumn equinox precipitation. For example, climate warming will lead to the increase of water vapor content in the atmosphere, thus increasing the probability of precipitation in autumn equinox.

Benefits of rainy autumn equinox:

1, drought resistance: the rainfall before the autumnal equinox helps to alleviate the previous drought, provide sufficient water for crops, and is beneficial to the growth and development of crops.

2. Increase soil moisture: Rainwater can increase soil moisture, make crop roots better absorb water and nutrients, and promote crop growth.

3. Improve soil quality: Rainwater helps to dissolve fertilizers in the soil, provide nutrients for crops and improve soil quality.

4. Promote biodiversity: More rain will increase the vitality and reproductive capacity of vegetation and help maintain ecological balance and biodiversity.

5. Alleviate the problem of urban waterlogging: Rainwater can alleviate the problem of urban waterlogging and reduce the pressure on urban drainage system.

6. Promote the development of tourism: The autumnal equinox is a good season for tourism, and more rain will increase the beauty of the natural landscape and attract tourists to watch it.