The introduction of artificial substances (usually silver iodide or dry ice) into a cloud for the purpose of either modifying its development or increasing its precipitation.

process of adding chemical material to clouds in order to make it rain or otherwise control precipitation.

The addition of agents (aerosol, small ice particles) that will alter the phase and size distribution of cloud particles, with the intent of influencing precipitation. The most frequently used agents [..]

attempt to create or grow clouds by the introduction of condensation nuclei in order to cause greater precipitation.

The dispersal of crystals or particles into clouds to cause the release of precipitation (e.g. rain or snow).

An experimental process used to weaken hurricanes or make rain in dry areas.

 A form of weather modification used to change the amount of precipitation from clouds, often achieved by dispersing substances into the air.