Ice Crystal Habit Discrimination with the Optical Backscatter Depolarization Technique

Abstract

Ice crystal habit identification is shown to be accomplished through an analysis of the backscattered signals from single ice crystals (sampled in a small cloud volume) which relates the relative signal strengths of specular reflections and the scattering interactions which yield depolarized energy. Additionally, evidence is presented which indicates that the monitoring of the strength and frequency of specular reflections can be used to obtain estimates of the size distribution and concentration of populations of relatively minute ice crystals. These results in combination with previously reported depolarization measurements of larger and more complex hydrometeors suggest that the optical backscatter depolarization technique displays a significant potential for in situ cloud physics research.