The king discovered that many counties and remote areas had faced the problem of drought. Over 82 percent of Thai agricultural land relied on rainfall. Thai farmers were not able to grow crops for lack of water. The royal rainmaking project debuted on 20 July 1969 at his behest, when the first rainmaking attempt was made at Khao Yai National Park. Dry ice flakes were scattered over clouds. Reportedly, some rainfall resulted. In 1971, the government established the Artificial Rainmaking Research and Development Project within the Thai Ministry of Agriculture and Cooperatives.
Seeding hygroscopic chemicals stimulates a mass of air to rise higher to create humidity. This helps nature to form rain clouds, and it increases the potential amount of rainfall.
Fattening of the rain clouds is done by scattering exothermic-hygroscopic chemicals to make droplets of water condense.
Flying a plane through the heavy clouds accelerates the process of raindrop formation.