Coastal marine fog in southern California.

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. The methods are described, and analysis of the 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. - from Author