A Statistical Evaluation of the Kern River Operational Cloud Seeding Program

Authors

  • Bernard A. Silverman Consulting Meteorologist Centennial, CO, USA

DOI:

https://doi.org/10.54782/jwm.v40i1.189

Abstract

A target-control statistical evaluation of the KernRiver Basin operational cloud seeding program was conducted using ratio statistics. The cumulative effect of seeding from water year 1977 through water year 2006 was calculated in terms of confidence intervals because they provide information on the strength of the seeding effect whereas null hypothesis significance tests infer only whether there is any seeding effect at all. The effect of seeding on several targets in the Kern River Basin was evaluated using the controls that give the most precise evaluation results possible with the available data. Evidence for positive, statistically significant and cost effective seeding effects was found at all 3 target sites in the Kern River Basin that were evaluated with estimated increases instreamflow due to seeding ranging from +8.4% to +12.2%, depending on the target location. Physical studies that help explain the statistical results and that could lead to more cost-effective seeding operations are indicated.

Pooling of the estimates of the seeding effects for the Kern River, Kings River and San Joaquin River Basin operational cloud seeding programs indicated that the common effect of seeding on the three River Basins is +6.4% with 90% confidence thatthe true effect of seeding is somewhere between +3.9% and +9.0%. The probability that the seeding effect is greater than 0% and 1% (threshold of cost-effectiveness) are both 100%. Thus, there is strong statistical evidence in support of the hypothesis that cloud seeding in the watersheds of the Southern Sierra Nevada Mountains is a cost-effective technology for increasing streamflow by significant and societally important quantities.

Downloads

How to Cite

Silverman, B. A. (2008). A Statistical Evaluation of the Kern River Operational Cloud Seeding Program. The Journal of Weather Modification, 40(1), 7–16. https://doi.org/10.54782/jwm.v40i1.189

Issue

Vol. 40 No. 1 (2008)

Section

Scientific Papers

License

Authors that submit papers for publication agree to the Journal’s copyright and publication terms. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the manuscript’s authorship and initial publication in Journal of Weather Modification. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal’s published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in the Journal of Weather Modification. Authors are permitted to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process to encourage productive exchanges and greater citation of the published article.
 
Articles are published online using restricted access for the first year. After the first year, articles are made freely available online. Immediate open access for an article may be obtained by the author paying an open access fee which is in addition to the normal page changes. Authors are expected to honor a page charge in order to support publication and distribution of the journal. After the author approves the gallery formatted version for publication, the Weather Modification Association’s Secretary will invoice the corresponding author for the page charges and payment is due within 30 days.