Accession Number : AD0767934

Title :   Oceanic Fog, a Numerical Study.

Descriptive Note : Final rept.,

Corporate Author : ENVIRONMENTAL PREDICTION RESEARCH FACILITY (NAVY) MONTEREY CALIF

Personal Author(s) : Barker,Edward H.

Report Date : SEP 1973

Pagination or Media Count : 73

Abstract : A numerical model was developed for the simulation of fog and stratus in the marine planetary boundary layer. Physical processes described by the model are eddy diffusion, horizontal advection, fog droplet settling, infrared radiation and change of thermodynamic state of moist air. Results of the computations show the relative importance of the processes considered in the development of stratiform clouds in the planetary boundary layer. Among the most important factors governing the extent of fog are the magnitudes of horizontal advection of heat and infrared radiation by cloud and water vapor. Comparisons of the computational results with existing observations show that the formation process has been adequately described. Additionally, it was shown that occurrence of fog over the ocean could result in air temperature colder than that of the sea surface, caused by radiation heat loss from the cloud top. Results indicate that a practical fog forecast model is feasible with certain refinements, such as inclusion of the effects of haze on the infrared radiation balance, inversion strength on the growth of the mixing layer depth, and insolation. (Author)

Descriptors :   (*FOG, MARINE METEOROLOGY), WEATHER FORECASTING, MATHEMATICAL MODELS, WIND, WATER VAPOR, INFRARED RADIATION, ATMOSPHERIC TEMPERATURE, COMPUTER PROGRAMS

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE