From the point of view of harmony between man and nature, man can't control the weather, but he can influence it appropriately, and seek advantages and avoid disadvantages. the year of 2008

On August 8th, at the opening ceremony of Beijing Olympic Games, when gorgeous fireworks lit up the sky over Beijing, meteorologists carried out the largest weather modification operation in China, turning a rainstorm cloud belt from the southwest into invisible, which laid a solid foundation for the success of the opening ceremony.

Wang Guanghe introduced, "Aircraft artificial rain suppression is mainly aimed at relatively stable layered clouds, among which layered clouds are divided into Leng Yun and warm clouds." He said that for Leng Yun, silver iodide can be carried by aircraft and catalyzed in the cloud; If it is warm cloud, a hygroscopic warm cloud catalyst is used. For convective clouds that are prone to lightning, rockets are used to artificially eliminate rain.

Wang Guanghe said that on the afternoon of the opening ceremony, the meteorological department sent four planes to detect clouds and precipitation respectively and carry out warm cloud catalyst operations; The rocket ran from 6 pm to 1 1: 30, lasting about five and a half hours, and * * * launched 1 104 pieces.

Wang Guanghe said that the principle of artificial rain suppression is similar to that of artificial precipitation enhancement, but there are also differences. There are two ways to eliminate rain artificially. He introduced that, first, in the windward side of the target area, usually about 60- 120 km, artificial precipitation enhancement operations were implemented to end the rainfall ahead of schedule; Second, in the windward direction of the target area, usually about 30-60 kilometers, the ice cores are excessively sown in the clouds, so that the ice core content reaches 3 to 5 times of the precipitation standard. If the number of ice cores is large, each ice core absorbs less water and cannot form enough raindrops. In general, it is to let the rain "hold on".

On the general process of artificial rain suppression. Wang Guanghe said that first of all, we should carefully observe and predict the weather conditions and their changing trends to determine whether there is a possibility of rainfall. If it is found that there is a possibility of rain, it is necessary to further understand the possible influence trend of this weather system on the local area, as well as the possible time and place. After that, it is necessary to formulate an artificial rain suppression plan for the protected area. Once the operational conditions are met, the aircraft, ground rockets and anti-aircraft guns will be started immediately for combat. If it is affected by the mobile weather system, artificial precipitation enhancement should be carried out in the upstream area of the proposed protected area, so that the local rainfall that may occur in the upstream area will land ahead of time, so as to slow down or eliminate the rainfall in the proposed protected area; If the local cloud system develops to produce rainfall, it is necessary to over-broadcast the target cloud system to fully "eat" the water in the cloud, so that it is difficult for cloud droplets to grow into raindrops and land on the ground, thus reducing or eliminating rainfall.

He said that the impact of artificial rain suppression is relatively limited at present. It will achieve ideal results for small-scale and weak precipitation weather processes, but in the case of heavy precipitation weather processes, the current technical means can not achieve the effect of artificial precipitation elimination.