Space-borne active sensor cloud retrievals and evaluation by ground-based MFMSPL measurements

Abstract:

A physical model was developed to estimate the time delay of multiply scattered depolarized lidar returns from different vertical grids for space-borne lidars, and had been validated against direct Monte Carlo simulations. The method had been used to analyze CALIPSO data for improved estimates of low level cloud base, vertically resolved particle size and mass concentration of clouds, drizzle and light precipitation with the aid of CloudSat radar (Sato et al., 2015). On the other hand, a ground-based lidar system “Multiple-Field of view-Multiple-Scattering-Polarization Lidar (MFMSPL)” had been developed and operated with collocated cloud radar measurements to mimic satellite active sensor observations from ground (Okamoto et al., 2015). The MFMSPL has a similar conceptual design with the way the physical model had been constructed and observes the angular-resolved depolarized lidar returns within the FOV comparable to satellite footprints (e.g. CALIPSO). This makes it possible to observe optically thicker water clouds than conventional lidars, and suitable as a testbed for the satellite retrieval algorithms.