Prospects for Advancing Global Aerosol and Cloud Measurements with CALIPSO

Until recently, optical remote sensing from space has relied on passive techniques but satellite lidars are now beginning to add new atmospheric sensing capabilities. Following the Lidar In-space Technology Experiment (LITE) on the Space Shuttle in 1994, and the Geoscience Laser Altimeter System (GLAS) on the ICESat satellite in 2003, the CALIPSO satellite will carry the first polarization lidar in orbit. In addition to the lidar, CALIPSO carries infrared and visible passive imagers.

CALIPSO, under development for the last several years as a collaboration between NASA and CNES, is scheduled to launch this spring together with the CloudSat satellite, which carries a 95 GHz cloud profiling radar. CALIPSO and CloudSat will fly together in formation as part of the A-train, which currently includes the Aqua, Aura, and PARASOL satellites. CALIPSO contributes profiles of aerosols and thin clouds to complement passive measurements from MODIS, OMI, and other instruments in the A-train. CALIPSO's polarization-sensitive lidar can unambiguously identify the ice-water phase of clouds and also discriminate hydrated and dry aerosols. Coincident observations with CloudSat will provide for the first time a capability to profile all clouds, from thin cirus to deep convection, on a global scale. This talk will discuss capabilities of CALIPSO for observing clouds and aerosols, based on early assessments of on-orbit performance.