Evaluation of Raman Lidar Profiling of Atmospheric Water Vapor: Simultaneous Measurements with Two Advanced Systems

The Raman lidar technique has proven to be a powerful method for profiling atmospheric water vapor, one of the most important variables that characterizes the atmosphere. Detailed evaluation of the performance of Raman lidar systems (or lidar systems in general) is complicated by the lack of an appropriate instrument that can provide accurate measurements for intercomparison purposes. In this paper, we describe a detailed intercomparison program performed using two advanced Raman lidar systems. The paper treats in detail only a nighttime intercomparison of water vapor profiles, but the intercomparison program itself will feature daytime and nighttime measurements of both water vapor and aerosol scattering ratios.