Anomaly overview for five decades of global GEO-ring observations

Fundamental climate data records rely on consistent satellite observations, yet long-term geostationary (GEO) datasets are affected by various image anomalies. This work provides the most extensive overview to date of anomalies in the GEO-ring archive spanning five decades of data from; Meteorological Satellite (Meteosat), Himawari, Synchronous Meteorological Satellite (SMS), and Geostationary Operational Environmental Satellite (GOES) satellites. This work provides a common reference for the community working with long-term geostationary archives. In total, 18 generic anomaly types have been identified, recurring across sensors. Furthermore, 14 specific anomaly types have been identified, which are limited to individual satellites. Each anomaly is described and illustrated, including the affected channels and satellite platforms. This catalogue provides a common reference for the analysis and interpretation of long-term geostationary image archives and forms the basis for the ongoing development of the GEO-ring Image Anomaly Detection software, which will support the production of fundamental climate data records by automatically identifying and masking anomalous observations. Future work will use this framework to quantify the prevalence of the identified anomaly types across the complete GEO-ring archive.