Monitoring and Calibration Activities in Support to the EarthCARE Mission
Niro, Fabrizio1; Fehr, Thorsten2; Caspar, Christophe2

The EarthCARE mission has been specifically designed with the objective to improve our understanding of the impact of clouds and aerosol in the Earth's radiation budget. In order to achieve its scientific objectives, the EarthCARE mission will make a synergistic use of the information on clouds aerosol and radiation provided by four different instruments: a Backscatter High Spectral Resolution Lidar (ATLID), a Doppler W-band Radar (CPR) provided by JAXA, a Multi-Spectral Imager (MSI) with 150km swath and 7 channels (4 solar and 3 thermal), and a Broadband Radiometer (BBR) with one short and one total wavelength channel.
The basic requirement for EarthCARE measurement is to allow the retrieval of Top-of-Atmosphere (TOA) combined short and long-wave flux with an accuracy of 10 Wm-2 for an instantaneous view with a footprint of 10 km x 10km. This accuracy value poses severe requirements on the instrument characterization and calibration activities both during the on-ground testing and during the in-flight operations. In addition, the instrument and processing performances should be carefully monitored along the mission, so that to maintain the accuracy requirement and to implement corrective actions in case of transient anomalies or long-term ageing effects. The in-flight calibration and the mission performances monitoring are the subject of this paper.
The aim of this paper is to illustrate the current approach for implementing the EarthCARE in-flight Calibration Plan and Monitoring Baseline within the Payload Data Ground Segment (PDGS). This approach is based on the development of a software facility (Monitoring and Calibration Facility) that will interface to the operational processor for receiving input data and distributing the associated output: auxiliary files and monitoring reports. This facility will support the mission ground and flight segment by generating, validating and disseminating relevant calibration parameters. In addition, this facility will provide support to science users and Cal/Val teams by providing short and long term performances reports about products quality.