Operational assimilation of space-borne radar and lidar cloud profile observations for numerical weather prediction. EarthCARE data handling and testing

This report details the specific modifications to the assimilation system at European Centre for Medium Range Weather Forecasts (ECMWF) that will be required for the inclusion of Earth, Clouds, Aerosols and Radiation Explorer (EarthCARE) cloud radar and lidar data directly into the Four-Dimensional Variational (4D-Var) system. The work is divided into three sections. Firstly, the differences between EarthCARE observations compared to CloudSat (NASA's cloud radar mission) and CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) data are considered and updates to the forward models are made. Secondly, the off-line observation handling of raw EarthCARE L1b data into Binary Universal Format (BUFR) is outlined. In particular, the capability of EarthCARE's High Spectral Resolution Lidar (HSRL) to separate Mie and Rayleigh signals is accounted for.  Finally, the system is tested using simulated EarthCARE nominal data of radar reflectivity and attenuated backscatter, where data flow through the assimilation system is tested.