The RASCALS SYSTEM: a tool for ERS-1 data product quality analysis and sensor performance assessment

RASCALS (Radar Altimeter and SCAtterometer Long-term Surveillance) is a software system dedicated to the monitoring and analysis of sensor performance and data product quality for the ERS-1 wind scatterometer and radar altimeter. It is operated by the ERS-1 Product Control Service at ESRIN/Earthnet. The system can access raw data and fast delivery products as well as instrument housekeeping data generated by the AMI wind mode, the AMI wave mode, and the radar altimeter. The functionality covered by the RASCALS system ranges from the graphical visualisation of all parameters provided in the data products up to specialized analysis functions supporting the geophysical validation of measurements. RASCALS provides two modes of operation: In the analysis mode, the operator can interactively display, investigate and process the relevant data. In the routine mode, the system periodically samples the data products available from radar altimeter and wind scatterometer and extracts from the engineering and geophysical data a set of statistical parameters, thus building up a database characterizing the long-term performance. This paper describes the functionality and applications of RASCALS