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available to them and began preliminary studies of possible cloud seeding techniques. " In 1969, the Permanent Secretary of Agriculture requested Dr. Devakul to form a task force to undertake field studies of seeding of" clouds. These preliminary studies were conducted over a mountain barrier (1300 m) during the period JUly 18-21, 1969, at the Kao Yai National Park, Nakhon Ratchasima Province of Thailand. The operation used a Cessna 180 and seeded with dry ice. After two afternoon cloud-top seeding flights, the clouds were reported to have turned grey and moved downwind, but no one was able to see if it rained from the seeded clouds. During 5-31 August 1969, the studies were moved to Prachuap Khiri Kahn, Hua Hin District, and two aircraft were used to seed at cloud tops and bases with dry ice, water spray, salt in solution, and mixtures of the three. Seeding was performed in the lee of mountains. There were 10 days of seeding with observers reporting that on 2 days there was rain in the target areas, on 4 days there was rain near the target areas, on 2 days there was rain far away from the target areas, and on 2 days there was no rain at all. The two targets were a rice area of about 1000 rai in the Thai-Israel project and the Kao Tao village reservoir (1 km from the east coast). Two additional test days were completed on 14-15 January 1970, in the Hua Hin District over two targets with the same seeding agents. Observations indicated that heavy rain occurred over both targets on the second day. Following these preliminary tests, a report and proposal were submitted in February 1970 to the Prime Minister requesting temporary funding for a "Rai nmaki ng Project. II The Prime Mi ni ster formed an i ntergovernmenta 1 com- mittee to develop and recommend policy. In March 1971, the intergovernmen- tal comnittee agreed with the proposal that the "rainmaking efforts" should be viewed as research and be conducted in the catchment areas of the Bhumipol and Ubol Ratana Reservoirs. These recommendations resulted in the establishment of the "Artificial Rainmaking Research and Development Project" within the Ministry of Agriculture and Cooperatives with a separate budget. However, in July 1971, the rice farmers in the Phichit Province submitted a request to the King for 'Irainmaking" in their central plains areas. The King agreed and during August and part of September, clouds were seeded in a number of provinces in the central plains. Farmers even flew in the seeding aircraft helping with targeting. During September and October, the rainmaking team conducted a number of flights in the south region, and from late October to early November, the team conducted seeding in the Nakhon Sawan Province back in the central region. These activities provided the basis for launching a continuing seeding program after 1971. In September 1975, the Prime Minister signed a Royal Decree reorganizing the Office of the Under-Secretary (later called the Permanent Secretary) of the Ministry of Agriculture and Cooperatives. As part of this reorganiza- tion the Royal Rainmaking Research and Development Institute was created. Section III E summarizes the RRRDI's activities in weather modification after 1975. ^. . ~ ;? ~ 12