Articles | Volume 19, issue 10
https://doi.org/10.5194/amt-19-3539-2026
© 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-19-3539-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
29 May 2026
Research article |
| 29 May 2026
| 29 May 2026
Extraction of spatially confined small-scale waves from high-resolution all-sky airglow images based on machine learning
Erdbeobachtungszentrum, Deutsches Zentrum für Luft- und Raumfahrt Oberpfaffenhofen, 82234 Wessling, Germany
Jakob Strutz
formerly at: Erdbeobachtungszentrum, Deutsches Zentrum für Luft- und Raumfahrt Oberpfaffenhofen, 82234 Wessling, Germany
now at: Infineon Technologies AG, Germany
Patrick Hannawald
Erdbeobachtungszentrum, Deutsches Zentrum für Luft- und Raumfahrt Oberpfaffenhofen, 82234 Wessling, Germany
Jonas Steffen
formerly at: Institut für Physik, Universität Augsburg, 86159 Augsburg, Germany
Rainer Lienhart
Institut für Informatik, Universität Augsburg, 86159 Augsburg, Germany
Michael Bittner
Erdbeobachtungszentrum, Deutsches Zentrum für Luft- und Raumfahrt Oberpfaffenhofen, 82234 Wessling, Germany
Institut für Physik, Universität Augsburg, 86159 Augsburg, Germany
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dynamicepisodes of strong movement in the OH* airglow caused predominantly by waves can be extracted automatically from large data sets. Within these dynamic episodes, turbulent wave breaking can also be found. We use these observations of turbulence to derive the energy released by waves.
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Ground-based OH* airglow measurements have been carried out for almost 100 years. Advanced detector technology has greatly simplified the automatic operation of OH* airglow observing instruments and significantly improved the temporal and/or spatial resolution. Studies based on long-term measurements or including a network of instruments are reviewed, especially in the context of deriving gravity wave properties. Scientific and technical challenges for the next few years are described.
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High-resolution images of the OH* airglow layer (ca. 87 km height) acquired at Otlica Observatory, Slovenia, have been analysed. A statistical analysis of small-scale wave structures with horizontal wavelengths up to 4.5 km suggests strong presence of instability features in the upper mesosphere or lower thermosphere. The dissipated energy of breaking gravity waves is derived from observations of turbulent vortices. It is concluded that dynamical heating plays a vital role in the atmosphere.
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Short summary
Since June 2019, an infrared camera has been scanning the nearly entire sky (diameter: 500 km) above DLR Oberpfaffenhofen (48.09° N, 11.28° E), Germany, every night providing images of the OH* airglow layer (height: 85–87 km), with a high spatial and temporal resolution (150 m, 2 min). We analysed three years of data for spatially confined small-scale wave structures with a machine learning approach. We derived seasonal variations and deduced that wave breaking is mostly observed in summer.
Since June 2019, an infrared camera has been scanning the nearly entire sky (diameter: 500 km)...
