Initial assessment of space‐based lidar CALIOP aerosol and cloud layer structures through inter‐comparison with a ground‐based back‐scattering lidar and CloudSat

Abstract

This study presents results of the intercomparison of aerosol/cloud top and bottom heights obtained from a space‐borne active sensor Cloud‐Aerosol Lidar with Orthogonal Polarization (CALIOP) onboard CALIPSO, and the Cloud Profiling Radar (CPR) onboard CloudSat, and the space‐borne passive sensor Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Aqua, and ground‐based 2‐wavelenght polarization lidar system (532 and 1064 nm) at Seoul National University (SNU), Seoul, South Korea. This result confirms that the CALIPSO science team algorithms for the discrimination of cloud and aerosol as well as for the detection of layer top and base altitude provide reliable information both under cloud‐free conditions and in cases of multiple aerosol layers underlying semi‐transparent cirrus clouds. Simultaneous space‐borne CALIOP, CPR and ground‐based SNU lidar (SNU‐L) measurements complement each other and can be combined to provide full information on the vertical distribution of aerosols and clouds, especially for thick opaque clouds. The aerosol extinction profiles from both lidars show good agreement for aerosols within the planetary boundary layer under cloud‐free conditions and for the night‐time CALIOP flight.