Lidar and radiosonde measurements of coastal atmospheric refraction

During the period June-October 1993, a series of measurements were carried out during Project VOCAR to investigate the properties of the coastal atmosphere over the southern California coastal zone, including the offshore Sea Test Range operated by the Naval Air Warfare Center Weapons Division (NAWCWPNS), Point Mugu, California. During summer, this region is frequented by persistent and strong radio/radar ducting conditions, in a refractive environment similar to those which impact Fleet operations in certain weather regimes worldwide. Characterization of the variability of refractive conditions in the lower atmosphere is a key element of the VOCAR study. Measurements at Point Mugu (about 60 miles northwest of Los Angeles) were made with a number of remote and direct sensing techniques, providing an opportunity to examine their respective capabilities to determine atmospheric refraction and related properties for radar/radio performance assessment applications. Some early results are presented from comparisons of refractive profiles from radiosonde data and an atmospheric lidar, developed and operated by Pennsylvania State University Applied Research Laboratory personnel.