This paper assesses the radiometric performance of the Arctic Weather Satellite (AWS) with respect to the ECMWF data assimilation system and heritage sensors. The AWS is the first mission of the European Space Agency designed according to “NewSpace” principles. Its objective is to improve weather forecasting through a rapidly developed, low-cost mission. AWS also serves as a pathfinder for the recently approved Polar System (EPS) Sterna constellation, representing a paradigm shift in operational satellite meteorology. Despite its compact size, AWS has proven to be a high-performing radiometer, delivering data quality suitable for operational assimilation in numerical weather prediction, where it has been used operationally for nearly one year.

This work describes a technique for the real-time determination of aerosol sources using high temporal resolution measurements to determine rapid changes in particle size distribution in accumulation and coarse modes, along with measurements of spectrally resolved light absorption measurements in the near-UV to near-IR range. The paper presents relevant real-time applications, including emergency surveillance during accidental events and the rapid identification of long-range transport of secondary particles, desert dust, and smoke. The documented approach is transferable to air quality networks involved in aerosol mass source apportionment as it relies on optical instruments commonly employed by regulatory government agencies.