ECMWF Research Activities for the Monitoring and Assimilation of Spaceborne Lidar and Radar Observations in Clouds
DiMichele, Sabatino; Janiskova, Marta; Martins, Edouard

Space-borne active instruments, providing a three-dimensional characterization of clouds, promise a new dimension of information to be used in numerical weather prediction (NWP) systems. Observations from CloudSat and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) have given unique insights in cloud processes. Research activities are ongoing at the European Centre for Medium-Range Weather Forecasts (ECMWF) to exploit these data for monitoring and assimilation. This work paves the way to the use of similar observations from the planned EarthCARE (Earth Clouds, Aerosols and Radiation Explorer) mission in the ECMWF monitoring and assimilation system. The presentation will summarise the developments done to perform the monitoring and assimilation of cloud radar and lidar observations in the context of our NWP system. First, the forward operators that transform model output into the equivalent radar and lidar cloud observations will be described. Then, the main components needed for a proper handling of these observations in the monitoring and assimilation system will be discussed. In particular, the definition of observation errors, the quality control strategy and the bias correction scheme, will be presented. Finally, the results of some CloudSat and CALIPSO monitoring and assimilation experiments will be shown.