Toward a quantitative characterization of heterogeneous ice formation with lidar/radar: Comparison of CALIPSO/CloudSat with ground-based observations

We analyze and compare the different sensitivities of aerosol/cloud lidar and 35-GHz cloud radar to detect ice formation in midlevel clouds in order to harmonize mixed phase cloud observations performed with lidar and radar. We found good agreement between spaceborne Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO)/CloudSat and ground-based lidar/radar observations at Leipzig, Germany. However, large differences were found to a previous study with an 11-year cloud statistics solely based on lidar observations which is caused by significantly higher sensitivity of the cloud radar to detect ice crystals. By introducing a lidar detection threshold for the ice water content of 10–6 kg m–3 , we find that lidar and radar cloud statistics become increasingly similar.