Document Type


Publication Date

January 1975


In the past, considerable effort has been spent on the development of techniques for increasing precipitation from a given cloud formation. However, little attention has been given to identifying and evaluating the impacts of cloud seeing activities on the aquatic ecosystems within the affected areas. The objective of this study was to apply the simulation technique to predict the impacts of cloud seeing on the aquatic ecosystem within the area subject to weather modification. A small mountain watershed near Logan, Utah, was selected for the study. Measurements were made of the significant parameter levels under current conditions. A hydrologic and water temperature model was calibrated to the watershed to predict the change in water temperature and stream velocities from arbitrary increases in the snowpack. The predicted water velocities and temperatures were used to link the hydrologic system to the aquatic ecosystem which consisted of primary production, invertebrate, and fish communities. The study was conducted over a very short time base, and thus cannot be regarded as being absolutely conclusive, but the results do indicate trends which might be expected if various decreases of water temperature and increases in stream velocity were to occur.