NASA - National Aeronautics and Space Administration

A-Train platforms offer the possibility of measuring the same physical parameters using active and passive instruments, to improve our understanding of geophysical processes in the Earth system. In this letter, a new calibration approach is developed using active [Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar and CloudSat radar] and passive [Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E)] instruments. The parameters of an existing oceanic surface model are first adjusted to give consistent sea surface scattering properties for CALIPSO and CloudSat observations. Revisiting the lidar/radar data analysis procedure using this model, as well as sea surface wind speed, the temperature and water vapor products of the microwave radiometer (AMSR-E) allowed one to refine the calibration factors for both lidar and radar observations in a coherent approach. This study also improves other applications such as the retrieval of atmospheric attenuation from aerosols at optical wavelengths.