Articles | Volume 19, issue 11
https://doi.org/10.5194/amt-19-3581-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-19-3581-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
02 Jun 2026
Research article | Highlight paper |
| 02 Jun 2026
| 02 Jun 2026
Arctic Weather Satellite assessment and assimilation at ECMWF
ECMWF, Reading, UK
Niels Bormann
ECMWF, Reading, UK
Marijana Crepulja
ECMWF, Reading, UK
Mohamed Dahoui
ECMWF, Reading, UK
Alan J. Geer
ECMWF, Reading, UK
Christophe Accadia
EUMETSAT, Darmstadt, Germany
Sabatino Di Michele
EUMETSAT, Darmstadt, Germany
Tim J. Hewison
EUMETSAT, Darmstadt, Germany
Ville Kangas
ESA, Noordwijk, the Netherlands
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We studied how common unwanted man-made radio frequency interferes affect Earth observation satellites used for weather and climate studies. We scanned frequencies from 6 to 200 GHz in 2022. We found strong interference at lower ranges, including first signs at 23.8 and 36.5 gigahertz, while higher ranges were mostly clean. These results highlight the need for real-time monitoring, stronger protection from authorities, and on-board and on-ground mitigation systems in EO missions.
Simon Pfreundschuh, Stuart Fox, Patrick Eriksson, David Duncan, Stefan A. Buehler, Manfred Brath, Richard Cotton, and Florian Ewald
Atmos. Meas. Tech., 15, 677–699, https://doi.org/10.5194/amt-15-677-2022, https://doi.org/10.5194/amt-15-677-2022, 2022
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We test a novel method to remotely measure ice particles in clouds. This is important because such measurements are required to improve climate and weather models. The method combines a radar with newly developed sensors measuring microwave radiation at very short wavelengths. We use observations made from aircraft flying above the cloud and compare them to real measurements from inside the cloud. This works well given that one can model the ice particles in the cloud sufficiently well.
Raul Onrubia, Roger Oliva, David Duncan, Niels Bormann, Jose Barbosa, Ioannis Nestoras, Adriano Jordão, Flavio Jorge, Juliette Challot, and Yan Soldo
EGUsphere, https://doi.org/10.5194/egusphere-2025-4838, https://doi.org/10.5194/egusphere-2025-4838, 2025
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We studied how common unwanted man-made radio frequency interferes affect Earth observation satellites used for weather and climate studies. We scanned frequencies from 6 to 200 GHz in 2022. We found strong interference at lower ranges, including first signs at 23.8 and 36.5 gigahertz, while higher ranges were mostly clean. These results highlight the need for real-time monitoring, stronger protection from authorities, and on-board and on-ground mitigation systems in EO missions.
Patrick Eriksson, Anders Emrich, Kalle Kempe, Johan Riesbeck, Alhassan Aljarosha, Olivier Auriacombe, Joakim Kugelberg, Enne Hekma, Roland Albers, Axel Murk, Søren Møller Pedersen, Laurenz John, Jan Stake, Peter McEvoy, Bengt Rydberg, Adam Dybbroe, Anke Thoss, Alessio Canestri, Christophe Accadia, Paolo Colucci, Daniele Gherardi, and Ville Kangas
Atmos. Meas. Tech., 18, 4709–4729, https://doi.org/10.5194/amt-18-4709-2025, https://doi.org/10.5194/amt-18-4709-2025, 2025
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The Arctic Weather Satellite (AWS), developed by the European Space Agency, highlights a new approach in satellite design, aiming to expand the network of operational microwave sensors cost-effectively. Launched in August 2024, AWS features a 19-channel microwave cross-track radiometer. Notably, it introduces groundbreaking channels at 325.15 GHz. In addition, AWS acts as the stepping stone to a suggested constellation of satellites, denoted as EUMETSAT Polar System Sterna.
Rohit Mangla, Mary Borderies, Philippe Chambon, Alan Geer, and James Hocking
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This study provides a detailed description of the radar simulator available within version 13 of the RTTOV (Radiative Transfer for the TIROS Operational Vertical Sounder) software. It is applied to the Météo-France global numerical weather prediction model, with the objective of simulating Dual-frequency Precipitation Radar reflectivity observations. Additionally, the simulation of the bright band is addressed and then successfully applied to model forecasts for the purpose of classifying NWP (numerical weather prediction) model columns between stratiform and convective categories.
Simon Pfreundschuh, Stuart Fox, Patrick Eriksson, David Duncan, Stefan A. Buehler, Manfred Brath, Richard Cotton, and Florian Ewald
Atmos. Meas. Tech., 15, 677–699, https://doi.org/10.5194/amt-15-677-2022, https://doi.org/10.5194/amt-15-677-2022, 2022
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We test a novel method to remotely measure ice particles in clouds. This is important because such measurements are required to improve climate and weather models. The method combines a radar with newly developed sensors measuring microwave radiation at very short wavelengths. We use observations made from aircraft flying above the cloud and compare them to real measurements from inside the cloud. This works well given that one can model the ice particles in the cloud sufficiently well.
Alan J. Geer, Peter Bauer, Katrin Lonitz, Vasileios Barlakas, Patrick Eriksson, Jana Mendrok, Amy Doherty, James Hocking, and Philippe Chambon
Geosci. Model Dev., 14, 7497–7526, https://doi.org/10.5194/gmd-14-7497-2021, https://doi.org/10.5194/gmd-14-7497-2021, 2021
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Satellite observations of radiation from the earth can have strong sensitivity to cloud and precipitation in the atmosphere, with applications in weather forecasting and the development of models. Computing the radiation received at the satellite sensor using radiative transfer theory requires a simulation of the optical properties of a volume containing a large number of cloud and precipitation particles. This article describes the physics used to generate these
bulkoptical properties.
Sebastien Massart, Niels Bormann, Massimo Bonavita, and Cristina Lupu
Geosci. Model Dev., 14, 5467–5485, https://doi.org/10.5194/gmd-14-5467-2021, https://doi.org/10.5194/gmd-14-5467-2021, 2021
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Numerical weather predictions combine data from satellites with atmospheric forecasts. Some satellites measure the radiance emitted by the Earth's surface. To use this data, one must have knowledge of the surface properties, like the temperature of the thin layer above the surface. Error in this temperature leads to a misuse of the satellite data and affects the quality of the weather forecast. We updated our approach to better estimate this temperature, which should help improve the forecast.
Alan J. Geer
Atmos. Meas. Tech., 14, 5369–5395, https://doi.org/10.5194/amt-14-5369-2021, https://doi.org/10.5194/amt-14-5369-2021, 2021
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Satellite observations sensitive to cloud and precipitation help improve the quality of weather forecasts. However, they are sensitive to things that models do not forecast, such as the shapes and sizes of snow and ice particles. These details can be estimated from the observations themselves and then incorporated in the satellite simulators used in weather forecasting. This approach, known as parameter estimation, will be increasingly useful to build models of poorly known physical processes.
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Editorial statement
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 paper assesses the radiometric performance of the Arctic Weather Satellite (AWS) with...
Short summary
Satellite data used in weather forecast models needs to be of a very high quality. Previously, this has been delivered by bus-sized satellites. The new Arctic Weather Satellite shifts this paradigm, delivering high quality observations from a small satellite. Here we analyse the performance and test its impact with a state-of-the-art weather forecast model. It compares well to heritage instruments and has a positive impact on forecast skill.
Satellite data used in weather forecast models needs to be of a very high quality. Previously,...
