Articles | Volume 26, issue 2
https://doi.org/10.5194/nhess-26-943-2026
© 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/nhess-26-943-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Feb 2026
Research article |
| 27 Feb 2026
| 27 Feb 2026
First mapping of a tsunami wavefield by SWOT satellite: observation data and preliminary numerical simulation of the 19 May 2023 tsunami near the Loyalty Islands
Earth Sciences New Zealand, Earth Structure and Processes, Lower Hutt 5011, Aotearoa New Zealand
Yannice Faugère
Centre National d'Etudes Spatiale (CNES), Toulouse 31400, France
Hélène Hébert
CEA, DAM, DIF, Arpajon 91297, France
Antoine Delepoulle
Collecte Localisation Satellites (CLS), Ramonville-Saint-Agne 31520, France
Gérald Dibarboure
Centre National d'Etudes Spatiale (CNES), Toulouse 31400, France
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Antonio Sánchez-Román, M. Isabelle Pujol, Yannice Faugère, and Ananda Pascual
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Oscar Vergara, Rosemary Morrow, Marie-Isabelle Pujol, Gérald Dibarboure, and Clément Ubelmann
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Jean Roger, Bernard Pelletier, Aditya Gusman, William Power, Xiaoming Wang, David Burbidge, and Maxime Duphil
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Maxime Ballarotta, Clément Ubelmann, Pierre Veillard, Pierre Prandi, Hélène Etienne, Sandrine Mulet, Yannice Faugère, Gérald Dibarboure, Rosemary Morrow, and Nicolas Picot
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Marie-Isabelle Pujol, Stéphanie Dupuy, Oscar Vergara, Antonio Sánchez-Román, Yannice Faugère, Pierre Prandi, Mei-Ling Dabat, Quentin Dagneaux, Marine Lievin, Emeline Cadier, Gérald Dibarboure, and Nicolas Picot
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-292, https://doi.org/10.5194/essd-2022-292, 2022
Manuscript not accepted for further review
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An altimeter sea level along-track level-3 product with a 5 Hz (~1.2 km) sampling is proposed. It takes advantage of recent advances in radar altimeter processing, and improvements made to different stages of the processing chain. Compared to the conventional 1 Hz (~7 km) product, it significantly improves the observability of the short wavelength signal in open ocean and near coast areas (> 5 km). It also contributes to improving high resolution numerical model outputs via data assimilation.
Mounir Benkiran, Pierre-Yves Le Traon, and Gérald Dibarboure
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Clément Ubelmann, Loren Carrere, Chloé Durand, Gérald Dibarboure, Yannice Faugère, Maxime Ballarotta, Frédéric Briol, and Florent Lyard
Ocean Sci., 18, 469–481, https://doi.org/10.5194/os-18-469-2022, https://doi.org/10.5194/os-18-469-2022, 2022
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Cori Pegliasco, Antoine Delepoulle, Evan Mason, Rosemary Morrow, Yannice Faugère, and Gérald Dibarboure
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Pierre Prandi, Jean-Christophe Poisson, Yannice Faugère, Amandine Guillot, and Gérald Dibarboure
Earth Syst. Sci. Data, 13, 5469–5482, https://doi.org/10.5194/essd-13-5469-2021, https://doi.org/10.5194/essd-13-5469-2021, 2021
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We investigate how mapping sea level in the Arctic Ocean can benefit from combining data from three satellite radar altimeters: CryoSat-2, Sentinel-3A and SARAL/AltiKa. A dedicated processing for SARAL/AltiKa provides a baseline for the cross-referencing of CryoSat-2 and Sentinel-3A before mapping. We show that by combining measurements coming from three missions, we are able to increase the resolution of gridded sea level fields in the ice-covered Arctic Ocean.
Jean Roger, Bernard Pelletier, Maxime Duphil, Jérôme Lefèvre, Jérôme Aucan, Pierre Lebellegard, Bruce Thomas, Céline Bachelier, and David Varillon
Nat. Hazards Earth Syst. Sci., 21, 3489–3508, https://doi.org/10.5194/nhess-21-3489-2021, https://doi.org/10.5194/nhess-21-3489-2021, 2021
Short summary
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This study deals with the 5 December 2018 tsunami in New Caledonia and Vanuatu (southwestern Pacific) triggered by a Mw 7.5 earthquake that occurred southeast of Maré, Loyalty Islands, and was widely felt in the region. Numerical modeling results of the tsunami using a non-uniform and a uniform slip model compared to real tide gauge records and observations are globally well correlated for the uniform slip model, especially in far-field locations.
Sandrine Mulet, Marie-Hélène Rio, Hélène Etienne, Camilia Artana, Mathilde Cancet, Gérald Dibarboure, Hui Feng, Romain Husson, Nicolas Picot, Christine Provost, and P. Ted Strub
Ocean Sci., 17, 789–808, https://doi.org/10.5194/os-17-789-2021, https://doi.org/10.5194/os-17-789-2021, 2021
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Satellite altimetry has revolutionized ocean observation by allowing the sea level to be monitored with very good spatiotemporal coverage. However, only the sea level anomalies are retrieved; to monitor the whole oceanic signal a temporal mean (called mean dynamic topography, MDT) must be added to these anomalies. In this study we present the newly updated CNES-CLS18 MDT. An evaluation of this new solution shows significant improvements in both strong currents and coastal areas.
Cited articles
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Ballarotta, M., Ubelmann, C., Pujol, M.-I., Taburet, G., Fournier, F., Legeais, J.-F., Faugère, Y., Delepoulle, A., Chelton, D., Dibarboure, G., and Picot, N.: On the resolutions of ocean altimetry maps, Ocean Sci., 15, 1091–1109, https://doi.org/10.5194/os-15-1091-2019, 2019.
Ballarotta, M., Ubelmann, C., Veillard, P., Prandi, P., Etienne, H., Mulet, S., Faugère, Y., Dibarboure, G., Morrow, R., and Picot, N.: Improved global sea surface height and current maps from remote sensing and in situ observations, Earth Syst. Sci. Data, 15, 295–315, https://doi.org/10.5194/essd-15-295-2023, 2023.
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Chen, C.: Features of KaRIn Data that Users Should be Aware of, 2023 SWOT Science Team meeting, Toulouse, https://swotst.aviso.altimetry.fr/fileadmin/user_upload/SWOTST2023/20230919_3_Karin_overview2/14h10-KaRInFeatures.pdf (last access: 12 March 2024), 2023.
Delepoulle, A., Roger, J., Hébert, H., and Fuentes, M.: Tsunami records with the NASA/CNES SWOT space altimeter, EaSy Data [data set], https://doi.org/10.57932/8b9996d3-c100-4a0a-ac67-05dd2e81155a, 2026.
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Short summary
Deployed in 2022, the SWOT (Surface Water Ocean Topography) satellite was flying over the Southwest Pacific on 19 May 2023 when it recorded the tsunami triggered by a magnitude 7.7 earthquake south of the Vanuatu arc. For the very first time, it provided a 2D image of a tsunami wavefield along a straight path. Comparison with numerical tsunami simulations reveals good phase agreement between the modeled wavefield and the SWOT record, but the simulated amplitudes are lower than the measurements.
Deployed in 2022, the SWOT (Surface Water Ocean Topography) satellite was flying over the...
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