Cloud seeding is a type of weather modification that aims to change the amount or type of precipitation, mitigate hail or disperse fog. The usual objective is to increase rain or snow, either for its own sake or to prevent precipitation from occurring in days afterward.
This image explaining cloud seeding shows a substance – either silver iodide or dry ice – being dumped onto the cloud, which then becomes a rain shower. The process shown in the upper-right is what is happening in the cloud and the process of condensation upon the introduced material.
Ground Based Silver Iodide Generator – Colorado, US
Beech 18 used dry ice for cloud seeding in the early postwar era US
Lockheed 18 cloud seeding from Wagga Airport in 1958 Australia
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may compose the droplets and crystals. On Earth, clouds are formed as a result of saturation of the air when it is cooled to its dew point, or when it gains sufficient moisture from an adjacent source to raise the dew point to the ambient temperature.
Cloudscape over Borneo, taken by the International Space Station
Windy evening twilight enhanced by the Sun's angle, can visually mimic a tornado resulting from orographic lift
Cirrus fibratus clouds in March
High cirrus upper-left merging into cirrostratus right and some cirrocumulus far right