Experimental Test of Fog Clearing by Ground-Based Heating -- Visibility, Temperature, and Fog Microphysics

摘要

Experimental tests of fog clearing by a ground-based heating system were carried out in nighttime advection fog occurring at Vandenberg Air Force Base, California during July and August 1972. Horizontal visibility ranged from 400 to 1000 m at one meter above the ground, 100 to 200 m between the 1 and 30 m heights and 50 to 100 m between the 30 and 60 m heights; average liquid water contents were 0.08, 0.22 and 0.38 g/cubic meter at 1, 13, and 42 m heights, respectively. Extrapolating the results of these experiments to a similar system installed at an airport, it appears that the visibility improvement achieved would always be adequate to permit landings at category 2 and category 3a runways. The clearing would usually be inadequate for approaches to category 1 runways unless the quantity of heat used was significantly increased. (Author Modified Abstract)