Analysis of Cloud Seeding Potential in the Lemhi River Basin of Idaho

Wintertime precipitation is vital to the water resources and hydro-electric power in mountainous river basins in the west. In order to maintain and perhaps enhance wintertime precipitation, silver-iodide cloud seeding may be a solution. In this study, the Lemhi River Basin in Idaho was the focus of a climatology analysis to determine the feasibility for wintertime precipitation in the current and a future climate scenario. Two model simulations, the 4-km, 40-year Weather Research and Forecasting (WRF) simulation (CONUS404) and the 4-km, 13-year (CONUS-I) simulations for both current climate and a future climate scenario were used to evaluate atmospheric characteristics such as wind direction, liquid water content, temperature, precipitation and atmospheric stability.

Both airborne and ground level conditions were analyzed to determine when and how frequently airborne and ground based-dispersal of silver-iodide seeding would be effective given the atmospheric conditions at the two levels. The seeding conditions were determined by the presence of liquid water content at temperatures between -18 and -6°C. Ground based analysis also included wind and atmospheric stability to assess the likelihood that seeding material would effectively be dispersed over the targeted mountain barrier.

This presentation will share the results of the current and future climate analysis which quantifies that there is potential for cloud seeding in the Lemhi River Basin.