Basic principle of artificial rainfall

The basic principle of artificial rainfall is to choose suitable time according to the physical characteristics of different clouds and sow catalysts (such as dry ice, silver iodide, salt powder, etc.). ) carried into the cloud by planes and rockets to promote rainfall or increase precipitation.

Specifically, artificial rainfall can be divided into warm cloud rainfall and Leng Yun rainfall. For warm cloud rainfall, hygroscopic particles such as salt powder and urea should be sown in the cloud, so that some large water droplets can be obtained in the warm cloud as the starter of gravity collision, thus destroying the original stability of the warm cloud, realizing the existence of large and small water droplets and forming precipitation.

For the rainfall in Leng Yun, dry ice, silver iodide and other catalysts should be sown by plane, so that a large number of ice crystals can be produced in natural clouds, the density of ice crystals in the upper part of Leng Yun can be increased, and precipitation can be promoted or increased. The main methods of artificial rainfall are seeding catalyst and artificial precipitation enhancement. The methods of seeding catalyst include aircraft seeding and ground-lit smoke guns.

There are catalytic and non-catalytic methods for artificial precipitation enhancement, such as Leng Yun catalysis and warm cloud catalysis. In a word, artificial rainfall is a scientific method to intervene the weather process, which can help alleviate drought, increase irrigation water, provide clean water and increase power generation water.

Under certain conditions, the microphysical process of artificially influencing clouds can stimulate clouds that can't naturally precipitation, and can also make those clouds that have more water supply and can often naturally precipitation, improve precipitation efficiency and increase precipitation. However, cloud energy that can't naturally precipitation can supply less water, so the economic value of artificial catalysis is limited.

Matters needing attention in artificial rainfall:

1. Artificial rainfall operation can only obtain the result of increasing water quantity under certain natural cloud conditions, and the technical conditions are not yet suitable for artificial rainfall.

2. For clouds with different conditions, the same catalysis may lead to different positive and negative results. Therefore, in order to obtain the effect of artificial precipitation enhancement, it is necessary to conduct more in-depth detection and research on natural cloud conditions and precipitation processes.

3. The variability of natural precipitation is great, while artificial precipitation is often relatively small, so it is difficult to distinguish artificial precipitation from natural precipitation in a precipitation process. Therefore, it is still the main goal of weather modification science to evaluate the effect of artificial rainfall and its inspection method.

4. Artificial precipitation enhancement has gradually changed from the initial experimental research to the experimental application technology with rigorous design, diverse detection methods, modern operation technology and communication, and has become one of the measures to combat drought and reduce disasters in China and many countries.