WMOD00391 - Laserfiche WebLink

Home Browse Search

Evi dence about the potenti al for wi ntertime orographi c snowpack augmentation in the high mountains of the Colorado River Basin is based 1 argely on stati sti cal data from past projects such as the Cl imax (Mielke et al., 1981) and Wolf Creek Pass (Grant and Elliott, 1974) experiments conducted by Colorado State University and the Bureau of Reclamation'~Colorado River Basin Pilot Project (Elliott et al.~ 1978). These results. were consistent with the physical hypothesis that seeding under favorable conditions increases the precipitation efficiency of the cloud systems. In 1975 the comprehensive Westwide Study Report on Critical Water Problems Facing the Eleven Western States (USDOI, 1975) was released by the Secretary of the Interi or. The overall inadequacy of the natural water supply was acknowledged and the various augmentation options were examined. The report concluded: "Taking into consideration availability, quantity; quality, and cost of augmentation alternatives, weather modification appears to be the most promising source of new water supply in the Western United States." The validity of cloud seeding as a means of increasing precipitation was a major conclusion of the U. S. Secretary of Commerce's Weather Modification Advisory Board. The Board in its 1978 report, the Management of Weather Resources, stated: II In terms of sci entifi c and technol ogi cal underpi nni ng, and in consideration of probable high economic value, it is the judgment of thi s (Weather Modifi cati on Advi sory) Board that seedi ng wi nter orographi c storms to increase the amount of snow in the hi gh mountai nous watersheds of the West is the most advanced -- and closest to significant, broad-scale operational use -- of all cloud seeding possibilities. A suc- cessful confirmatory experiment -- including, of course, pro- vision for assessing the seeding results -- must be completed before large-scale seeding of winter orographic storms is con- sidered to be an acceptable tool, available to water resource decisionmakers.1I Recent advances in the technology of winter orographic cloud seeding resulting from programs such as the Bureau's Sierra Cooperative Pilot ~roject and the Colorado River Augmentation Demonstration Program have provided knowledge on which clouds should and could not be seeded. They have also developed new instrumentation and techniques for recognizing opportunities in real-time and reacting to them in a timely manner with more effective seeding delivery systems. Environmental effects Envi ronmental studi es such as the San Juan Ecology Project (Steinhoff and Ives, 1976) and' the Ui nta Ecology Project (Harper, 1981) I ........ "