Coastal Marine Fog in Southern California

Publisher Website
Google Scholar
Abstract
Multi-sensor and Multi-platform Observations of coastal marine fog along the coast of Southern California have been made since 1974 as part of a Navy program on marine fog. Details of the moisture and temperature mixing process in stratus cloud or fog deck were obtained by an FM-CW radar, an acoustic echo-sounder and an acoustic wind sensor in San Diego. Details of the vertical fog structure over the coastal waters were obtained by aircraft and the horizontal extent and position of fog decks were obtained by aircraft and visual and IR data acquired by the Defense Meteorological Satellite Project. Some surface air trajectories were determined from mesoscale analysts and some spatial and temporal fog intermittencies were determined near fog episodes. Statistical and time-change analyses of coastal radiosonde data were accomplished to obtain characteristic vertical structures. Consider jointly, these data have provided new knowledge on coastal marine fog in Southern California. The data substantiate the importance of radiation cloud-top cooling during fog episodes especially during the nighttime descent of stratus clouds and strongly support recent stratus cloud models (Barker, 1977; Oliver et al., 1978). The data also support the essential features of Leipper's (1948) model of fog development during Santa Ana conditions which stresses fog formation in moist air over cool water after passing over warmer water where moisture is acquired in the warm, dry Santa Ana air. Fog-top radiation cooling appears to aid in the maintenance of these Santa Ana related fogs. The models are difficult to apply because unknown mesoscale variations in convergence appear to control the height of the stratus cloud tops when cloud-top radiation is instigating a cloud thickening process and appear to create highly variable overwater air trajectories during Santa Ana conditions.

This publication has 0 references indexed in Scilit: