EUMETSAT PERFORMANCE ANALYSIS OF AWS TO PREPARE FOR EPS-STERNA

T. Hewison1, C. Accadia¹, J. Ackermann¹, V. Mattioli¹, S. Di Michele¹, I. Krizek¹, F. Bosco¹, P. Colucci¹, A. Canestri¹, G. Karsli Demirbas¹

¹EUMETSAT

The European Space Agency, ESA’s Arctic Weather Satellite (AWS) was launched on 16 August 2024. It is a small satellite carrying a cross-track scanning microwave radiometer with 19 channels from 50-325 GHz and is a prototype for a potential constellation of satellites, called EPS-Sterna.

A team from EUMETSAT have been evaluating the performance of AWS to assess the suitability of EPS-Sterna to provide information on atmospheric temperature, humidity and cloud profiles for Numerical Weather Prediction and nowcasting applications in line with the expected observation performance. The following aspects will be presented: thermal and radiometric calibration stability, noise, as well as geolocation and antenna performance. The calibration accuracy is also evaluated by calculating the relative bias with respect to other in-orbit microwave radiometers using methods such as Simultaneous Nadir Overpass (SNO) comparisons and Observation-minus-Background double-differences using NWP data. Additionally, lunar intrusions in the space views will be analysed to validate the predicted antenna beamwidths, and spacecraft manoeuvre data will be used to characterize scan-angle variations due to mirror reflectivity and antenna pattern corrections.