Lidar Evaluation of Fog Dissipation Techniques

During July 1972, laser radar (lidar) observations were made by Stanford Research Institute in support of a thermal fog dissipation program conducted by the Air Force at Vandenberg AFB. The program was designed to test the merging heat plume concept as a practical and efficient method of warm-fog dispersal. The ground-based heating system consisted of 213 liquid propane burners arranged in four lines perpendicular to the prevailing wind direction. The heat tests (conducted whenever fog reduced the horizontal visibility to less than 1/2 mile (800 m)) consisted to lighting various rows of burners at various burner intensities and spacings under various meteorological conditions (primarily wind speed variations). Profiles of atmospheric backscatter vs. range were observed with a ruby lidar at a point downwind from the ground-based heating system by firing every three seconds while scanning in a vertical plane normal to the wind. The observations are described and discussed in terms of their significance to demonstrating the operational feasibility of using lidar to document fog modification. (Author Modified Abstract)