Accession Number : AD0844971

Title :   Provision of Aircraft, Personnel and Services for the Field Application of Various NWC Pyrotechnic Nuclei Generators and Measurements of Related Meteorological Parameters.

Descriptive Note : Final rept.,

Corporate Author : NAVAL WEAPONS CENTER CHINA LAKE CA

Personal Author(s) : Henderson, Thomas J.

Report Date : OCT 1968

Pagination or Media Count : 33

Abstract : Field tests were made with NWC 2AL2 pyrotechnic units by Atmospherics Incorporated personnel in various areas. In the Yellowstone Park experiments, application of 2AL2 material in an environment of supercooled droplets near the ground (-5 degrees C to -20 degrees C) produced ice crystals of 1-100 microns diameter in concentrations of at least 1,000 per liter within 10 minutes. Substantial agglomeration with crystal orientation point to point or side to side was observed. In the Southern Sierra Range, visual effects associated with the application of pyrotechnic generated silver iodide nuclei to cumulus turrets were documented. It is obvious that pyrotechnic seeding initiated precipitation from clouds that would not have otherwise produced rainfall. In the Kericho tea growing area of Kenya, Africa, the units were used in the continuing hail suppression program. An examination of damage to tea following the passage of seeded hail producing cumulus revealed 50% less damage than that of unseeded storms. (Author)

Descriptors :   (*ARTIFICIAL PRECIPITATION, PYROTECHNICS), CUMULUS CLOUDS, CONDENSATION, FREEZING, SILVER COMPOUNDS, IODIDES, KENYA, CALIFORNIA, WYOMING, HAIL.

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE