Preliminary Assessment of the Potential of Artificial Stimulation

A study of rainfall stimulation was made with the aim of assessing its economic potential for the Natal cane belt. High variability of precipitation in both space and time makes the determination of requirements and effects of large scale seeding programmes very difficult. Evaluation of field and laboratory tests have, however, identified two conditions under which seeding could increase precipitation efficiency and these have been used in this study. The theory was used in two numerical models, designed to simulate cloud growth and development, in order to estimate the number of days when hygroscopic seeding or ice-phase seeding would have been successful. The analysis of Natal's climatic conditions indicates that a more detailed cloud census and a better measurement of their environmental conditions is essential for a realistic appraisal.