Articles | Volume 20, issue 1
https://doi.org/10.5194/tc-20-737-2026
© 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/tc-20-737-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Ensemble-based snow depth data assimilation for a multi-layer snow scheme over the European Arctic
Development Centre for Weather Forecasting, Norwegian Meteorological Institute, Oslo, Norway
Department of Geosciences, University of Oslo, Oslo, Norway
Jostein Blyverket
Development Centre for Weather Forecasting, Norwegian Meteorological Institute, Oslo, Norway
Malte Müller
Development Centre for Weather Forecasting, Norwegian Meteorological Institute, Oslo, Norway
Department of Geosciences, University of Oslo, Oslo, Norway
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Jean Rabault, Joey Voermans, Takehiko Nose, Graig Sutherland, Alexander Babanin, Takuji Waseda, Tsubasa Kodaira, Atle Jensen, Lars Willas Dreyer, Øyvind Breivik, Gaute Hope, Malte Müller, Zhaohui Cheng, Lichuan Wu, Aleksey Marchenko, Brian Ward, Kai H. Christensen, Petra Heil, and Karsten Trulsen
EGUsphere, https://doi.org/10.48550/arXiv.2507.19034, https://doi.org/10.48550/arXiv.2507.19034, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
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We observe harmonics of the main incoming wave peak in sea ice motion data. These harmonics match non-linear 3-wave interactions predicted from the dispersion relation. This may indicate that wave in ice triads are empirically observed, which suggests that non-linear energy transfers play a role in wave in ice propagation.
Cyril Palerme, Johannes Röhrs, Thomas Lavergne, Jozef Rusin, Are Frode Kvanum, Atle Macdonald Sørensen, Arne Melsom, Julien Brajard, Martina Idžanović, Marina Durán Moro, and Malte Müller
Geosci. Model Dev., 18, 9751–9766, https://doi.org/10.5194/gmd-18-9751-2025, https://doi.org/10.5194/gmd-18-9751-2025, 2025
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We present MET-AICE, a sea ice prediction system based on artificial intelligence techniques that has been running operationally since March 2024. The forecasts are produced daily and provide sea ice concentration predictions for the next 10 days. We evaluate the MET-AICE forecasts from the first year of operation, and we compare them to forecasts produced by three physically-based models. We show that MET-AICE is skillful and provides more accurate forecasts than the physically-based models.
Jean Rabault, Trygve Halsne, Ana Carrasco, Anton Korosov, Joey Voermans, Patrik Bohlinger, Jens Boldingh Debernard, Malte Müller, Øyvind Breivik, Takehiko Nose, Gaute Hope, Fabrice Collard, Sylvain Herlédan, Tsubasa Kodaira, Nick Hughes, Qin Zhang, Kai Håkon Christensen, Alexander Babanin, Lars Willas Dreyer, Cyril Palerme, Lotfi Aouf, Konstantinos Christakos, Atle Jensen, Johannes Röhrs, Aleksey Marchenko, Graig Sutherland, Trygve Kvåle Løken, and Takuji Waseda
The Cryosphere, 19, 6229–6260, https://doi.org/10.5194/tc-19-6229-2025, https://doi.org/10.5194/tc-19-6229-2025, 2025
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We observe strongly modulated waves-in-ice significant wave height using buoys deployed East of Svalbard. We show that these observations likely cannot be explained by wave-current interaction or tide-induced modulation alone. We also demonstrate a strong correlation between the waves height modulation, and the rate of sea ice convergence. Therefore, our data suggest that the rate of sea ice convergence and divergence may modulate wave in ice energy dissipation.
Are Frode Kvanum, Cyril Palerme, Malte Müller, Jean Rabault, and Nick Hughes
The Cryosphere, 19, 4149–4166, https://doi.org/10.5194/tc-19-4149-2025, https://doi.org/10.5194/tc-19-4149-2025, 2025
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Recent studies have shown that machine learning models are effective at predicting sea ice concentration, yet few have explored the development of such models in an operational context. In this study, we present the development of a machine learning forecasting system which can predict sea ice concentration at 1 km resolution up to 3 d ahead using real-time operational data. The developed forecasts predict the sea ice edge position with better accuracy than physical and baseline forecasts.
Cyril Palerme, Thomas Lavergne, Jozef Rusin, Arne Melsom, Julien Brajard, Are Frode Kvanum, Atle Macdonald Sørensen, Laurent Bertino, and Malte Müller
The Cryosphere, 18, 2161–2176, https://doi.org/10.5194/tc-18-2161-2024, https://doi.org/10.5194/tc-18-2161-2024, 2024
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Sea ice forecasts are operationally produced using physically based models, but these forecasts are often not accurate enough for maritime operations. In this study, we developed a statistical correction technique using machine learning in order to improve the skill of short-term (up to 10 d) sea ice concentration forecasts produced by the TOPAZ4 model. This technique allows for the reduction of errors from the TOPAZ4 sea ice concentration forecasts by 41 % on average.
Cyril Palerme and Malte Müller
The Cryosphere, 15, 3989–4004, https://doi.org/10.5194/tc-15-3989-2021, https://doi.org/10.5194/tc-15-3989-2021, 2021
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Methods have been developed for calibrating sea ice drift forecasts from an operational prediction system using machine learning algorithms. These algorithms use predictors from sea ice concentration observations during the initialization of the forecasts, sea ice and wind forecasts, and some geographical information. Depending on the calibration method, the mean absolute error is reduced between 3.3 % and 8.0 % for the direction and between 2.5 % and 7.1 % for the speed of sea ice drift.
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Short summary
Obtaining accurate estimates of seasonal snow conditions requires a combination of observations and numerical models. We use a model accounting for the vertical structure of the snow, and a data assimilation method representing varying uncertainty of the model in time and space. Compared to existing products, neglecting these considerations, our system produced improved estimates of seasonal snow conditions. Snow mass estimates suggest a potential impact on derived hydrological applications.
Obtaining accurate estimates of seasonal snow conditions requires a combination of observations...