Accession Number : AD0777978

Title :   On the Design of Warm Fog Clearing Experiments Using Hygroscopic Treatments.

Descriptive Note : Technical paper,

Corporate Author : NAVY WEATHER RESEARCH FACILITY NORFOLK VA

Personal Author(s) : Todd,C. J.

Report Date : SEP 1969

Pagination or Media Count : 8

Abstract : Hygroscopic treatment of warm fog has the potential of producing useful clearings of a few square miles that can last for an hour or more. This will be possible, though, only if the meteorological conditions are suitable and the treatment is appropriate for the fog and the operation. Large, long-lasting clearings can be expected only in relatively unpolluted fogs that have a slow reformation rate, or when continuous dispensing of the hygroscopic material in the required quantities may be feasible -- such as by means of ground-based dispensers. Effective treatment will involve dispersing the proper size of hygroscopic particles at the right number-density throughout the volume to be cleared. The wrong size or number-density can produce (1) a decrease of visibility, (2) no significant effect, or (3) clearing at a cost of 10 to 100 times the amount of material actually required.

Descriptors :   *Fog, *Weather modification, Hygroscopicity, Particle size, Turbulent diffusion, Condensation nuclei, Nucleation, Sprays, Visibility

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE