Environmental Impacts of Precipitation Management: Results and Inferences from Project Skywater.

Recent completion of several research projects into weather modification impacts on the environment provides an opportunity for placing this subject in a new perspective. Studies of physical and biological processes relating precipitation and ecosystem changes show relatively few discernible effects, all of them minor in nature and magnitude. Direct effects of nucleating agents no longer appear consequential Since no acute problems have surfaced, the focus is likely to shift to possible long-term effects on ecosystems as a whole, where changes associated with natural precipitation gradients and climatic fluctuations provide a model for those to be expected from precipitation management. The weakness of environmental impacts of weather modification compared to the consequences of other human actions renders it unlikely that these impacts will be decisive within a behavioral framework.