ACTRIS Supports Validation of ESA–JAXA EarthCARE Cloud Radar Observations

A new preprint, “Validation of EarthCARE CPR reflectivity using the ACTRIS cloud radar network,” highlights the key role of ACTRIS in verifying measurements from the recently launched EarthCARE satellite. The study, supported by the CNES, compares reflectivity profiles from EarthCARE’s Cloud Profiling Radar (CPR) with calibrated measurements from seven ACTRIS cloud radar sites across Europe. The results show a minimal bias between space-borne and ground-based measurements, confirming the high quality of the CPR calibration and its readiness for climate and atmospheric research applications.

The ground-based cloud radars used in this analysis were calibrated by the ACTRIS Centre for Cloud Remote Sensing (CCRES), whose mission is to ensure the traceability and consistency of cloud remote sensing observations across the network. This work once again demonstrates the value of ACTRIS as a reference infrastructure that can support the validation of new satellite missions.

The preprint is available here: https://doi.org/10.5194/egusphere-2026-925