Weather Modification Program for South Dakota

Physical and economic factors make it feasible for South Dakota to embark upon a state weather modification program to increase rain, reduce hail, and enhance knowledge concerning weather modification. Scientists have found that silver iodide seeding from aircraft in the Northern Plains can lead to more rain in the form of local showers, less hail from intense storms. They have also found that the introduction of hygroscopic materials into cumulus clouds can increase rainfall by increasing the efficiency of the precipitation process. Consequently, an amendment to South Dakota law was passed in 1971 to provide for a state program of weather modification, which sets the stage for the first program of this kind in the United States. The program should be organized to include local inputs on a decision-making level and a compromise between the short-term and long-term objectives of obtaining additional benefits and obtaining additional knowledge. Benefit-cost ratios are expected to be greater than 10:1.