Articles | Volume 18, issue 2
https://doi.org/10.5194/os-18-469-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-18-469-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
08 Apr 2022
Research article |
| 08 Apr 2022
| 08 Apr 2022
Simultaneous estimation of ocean mesoscale and coherent internal tide sea surface height signatures from the global altimetry record
Clément Ubelmann
CORRESPONDING AUTHOR
Ocean-Next, 90 chemin du Moulin, 38660 La Terrasse, France
Datlas, CS 40700 38058, Grenoble, CEDEX 9, France
Loren Carrere
Collecte Localisation Satellite, 11 rue Hermès, Parc Technologique du Canal 31520 Ramonville Saint-Agne, France
Chloé Durand
Collecte Localisation Satellite, 11 rue Hermès, Parc Technologique du Canal 31520 Ramonville Saint-Agne, France
Gérald Dibarboure
Centre National d'Etudes Spatiales, 18 avenue Edouard Belin, 31401 Toulouse, France
Yannice Faugère
Collecte Localisation Satellite, 11 rue Hermès, Parc Technologique du Canal 31520 Ramonville Saint-Agne, France
Maxime Ballarotta
Collecte Localisation Satellite, 11 rue Hermès, Parc Technologique du Canal 31520 Ramonville Saint-Agne, France
Frédéric Briol
Collecte Localisation Satellite, 11 rue Hermès, Parc Technologique du Canal 31520 Ramonville Saint-Agne, France
Florent Lyard
LEGOS, 14 avenue Edouard Belin, 31400 Toulouse, France
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Altimetry provides sea surface height (SSH) data along one-dimensional tracks. For many applications, the tracks are interpolated in space and time to provide gridded SSH maps. The operational SSH gridded products filter out the small-scale signals measured on the tracks. This paper evaluates the performances of a recently implemented dynamical method to retrieve the small-scale signals from real SSH data. We show a net improvement in the quality of SSH maps when compared to independent data.
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Recent advances allow us to observe the ocean from space with increasingly higher detail, challenging our knowledge of the ocean's surface height signature. We use a statistical approach to determine the spatial scale at which the sea surface height signal is no longer dominated by geostrophic turbulence but in turn becomes dominated by wave-type motions. This information helps us to better use the data provided by ocean-observing satellites and to gain knowledge on climate-driving processes.
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We present a new gridded sea surface height and current dataset produced by combining observations from nadir altimeters and drifting buoys. This product is based on a multiscale and multivariate mapping approach that offers the possibility to improve the physical content of gridded products by combining the data from various platforms and resolving a broader spectrum of ocean surface dynamic than in the current operational mapping system. A quality assessment of this new product is presented.
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Internal tides can have a signature of several centimeters at the ocean surface and need to be corrected from altimeter measurements. We present a detailed validation of several internal-tide models using existing satellite altimeter databases. The analysis focuses on the main diurnal and semidiurnal tidal constituents. Results show the interest of the methodology proposed, the quality of the internal-tide models tested and their positive contribution for estimating an accurate sea level.
Alice Laloue, Malek Ghantous, Yannice Faugère, Alice Dalphinet, and Lotfi Aouf
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Maxime Ballarotta, Clément Ubelmann, Valentin Bellemin-Laponnaz, Florian Le Guillou, Guillaume Meda, Cécile Anadon, Alice Laloue, Antoine Delepoulle, Yannice Faugère, Marie-Isabelle Pujol, Ronan Fablet, and Gérald Dibarboure
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Oscar Vergara, Rosemary Morrow, Marie-Isabelle Pujol, Gérald Dibarboure, and Clément Ubelmann
Ocean Sci., 19, 363–379, https://doi.org/10.5194/os-19-363-2023, https://doi.org/10.5194/os-19-363-2023, 2023
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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
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Manuscript not accepted for further review
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The SSH analysis and 7 d forecast error will be globally reduced by almost 50 %. Surface current forecast errors should be equivalent to today’s surface current analysis errors or alternatively will be improved (variance error reduction) by 30 % at the surface and 50 % for 300 m depth.
The resolution capabilities will be drastically improved and will be closer to 100 km wavelength as opposed to today where they are above 250 km (on average).
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Earth Syst. Sci. Data, 14, 1087–1107, https://doi.org/10.5194/essd-14-1087-2022, https://doi.org/10.5194/essd-14-1087-2022, 2022
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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.
Simon Barbot, Florent Lyard, Michel Tchilibou, and Loren Carrere
Ocean Sci., 17, 1563–1583, https://doi.org/10.5194/os-17-1563-2021, https://doi.org/10.5194/os-17-1563-2021, 2021
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Internal tides are responsible for surface deformations of the ocean that could affect the measurements of the forthcoming SWOT altimetric mission and need to be corrected. This study highlights the variability of the properties of internal tides based on the stratification variability only. A single methodology is successfully applied in two areas driven by different oceanic processes: the western equatorial Atlantic and the Bay of Biscay.
Jean-Michel Zigna, Reda Semlal, Flavien Gouillon, Ethan Davis, Elisabeth Lambert, Frédéric Briol, Romain Prod-Homme, Sean Arms, and Lionel Zawadzki
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-138, https://doi.org/10.5194/gmd-2021-138, 2021
Preprint withdrawn
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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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Florent H. Lyard, Damien J. Allain, Mathilde Cancet, Loren Carrère, and Nicolas Picot
Ocean Sci., 17, 615–649, https://doi.org/10.5194/os-17-615-2021, https://doi.org/10.5194/os-17-615-2021, 2021
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Since the mid-1990s, a series of FES (finite element solution) global ocean tidal atlases has been produced with the primary objective to provide altimetry missions with a tidal de-aliasing correction. We describe the underlying hydrodynamic/data assimilation design and accuracy assessments for the FES2014 release. The FES2014 atlas shows overall improved performance and has consequently been integrated in satellite altimetry and gravimetric data processing and adopted in ITRF standards.
Loren Carrere, Brian K. Arbic, Brian Dushaw, Gary Egbert, Svetlana Erofeeva, Florent Lyard, Richard D. Ray, Clément Ubelmann, Edward Zaron, Zhongxiang Zhao, Jay F. Shriver, Maarten Cornelis Buijsman, and Nicolas Picot
Ocean Sci., 17, 147–180, https://doi.org/10.5194/os-17-147-2021, https://doi.org/10.5194/os-17-147-2021, 2021
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Internal tides can have a signature of several centimeters at the ocean surface and need to be corrected from altimeter measurements. We present a detailed validation of several internal-tide models using existing satellite altimeter databases. The analysis focuses on the main diurnal and semidiurnal tidal constituents. Results show the interest of the methodology proposed, the quality of the internal-tide models tested and their positive contribution for estimating an accurate sea level.
Michel Tchilibou, Lionel Gourdeau, Florent Lyard, Rosemary Morrow, Ariane Koch Larrouy, Damien Allain, and Bughsin Djath
Ocean Sci., 16, 615–635, https://doi.org/10.5194/os-16-615-2020, https://doi.org/10.5194/os-16-615-2020, 2020
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This paper focuses on internal tides in the marginal Solomon Sea where LLWBCs transit. The objective is to characterize such internal tides and to give some insights into their impacts on water mass transformation in this area of interest for the global circulation. Results are discussed for two contrasted ENSO conditions with different mesoscale activity and stratification. Such study is motivated by the next altimetric SWOT mission that will be able to observe such phenomena.
Violaine Piton, Marine Herrmann, Florent Lyard, Patrick Marsaleix, Thomas Duhaut, Damien Allain, and Sylvain Ouillon
Geosci. Model Dev., 13, 1583–1607, https://doi.org/10.5194/gmd-13-1583-2020, https://doi.org/10.5194/gmd-13-1583-2020, 2020
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Consequences of tidal dynamics on hydro-sedimentary processes are a recurrent issue in estuarine and coastal processes studies, and accurate tidal solutions are a prerequisite for modeling sediment transport. This study presents the implementation and optimization of a model configuration in terms of bathymetry and bottom friction and assess the influence of these parameters on tidal solutions, in a macro-tidal environment: the Gulf of Tonkin (Vietnam).
Guillaume Taburet, Antonio Sanchez-Roman, Maxime Ballarotta, Marie-Isabelle Pujol, Jean-François Legeais, Florent Fournier, Yannice Faugere, and Gerald Dibarboure
Ocean Sci., 15, 1207–1224, https://doi.org/10.5194/os-15-1207-2019, https://doi.org/10.5194/os-15-1207-2019, 2019
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This paper deals with sea level altimetery products. These geophysical data are distributed as along-track and gridded data through Copernicus programs CMEMS and C3S. We present in detail a new reprocessing of the data (DT2018) from 1993 to 2017. The main changes and their impacts since the last version (DT2014) are carefully discussed. This comparison is made using an independent dataset. DT2018 sea level products are improved at the global and regional scale, especially in coastal areas.
Maxime Ballarotta, Clément Ubelmann, Marie-Isabelle Pujol, Guillaume Taburet, Florent Fournier, Jean-François Legeais, Yannice Faugère, Antoine Delepoulle, Dudley Chelton, Gérald Dibarboure, and Nicolas Picot
Ocean Sci., 15, 1091–1109, https://doi.org/10.5194/os-15-1091-2019, https://doi.org/10.5194/os-15-1091-2019, 2019
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This study investigates the resolving capabilities of the DUACS gridded products delivered through the CMEMS catalogue. Our method is based on the noise-to-signal ratio approach. While altimeter along-track data resolve scales on the order of a few tens of kilometers, we found that the merging of these along-track data into continuous maps in time and space leads to effective resolution ranging from ~ 800 km wavelength at the Equator to 100 km wavelength at high latitude.
Michel Tchilibou, Lionel Gourdeau, Rosemary Morrow, Guillaume Serazin, Bughsin Djath, and Florent Lyard
Ocean Sci., 14, 1283–1301, https://doi.org/10.5194/os-14-1283-2018, https://doi.org/10.5194/os-14-1283-2018, 2018
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This paper is motivated by the next SWOT altimetric mission dedicated to the observation of mesoscale and submesoscale oceanic features. It focuses on tropical areas with a strong discrepancy in the spectral signature between altimetry and models. The paper reviews the spectral signature of tropical turbulence which presents a rich variety of phenomena depending on the latitudinal dependence of the Coriolis force. Internal tides observed by altimetry explain the discrepancy with the model.
Fabrice Ardhuin, Yevgueny Aksenov, Alvise Benetazzo, Laurent Bertino, Peter Brandt, Eric Caubet, Bertrand Chapron, Fabrice Collard, Sophie Cravatte, Jean-Marc Delouis, Frederic Dias, Gérald Dibarboure, Lucile Gaultier, Johnny Johannessen, Anton Korosov, Georgy Manucharyan, Dimitris Menemenlis, Melisa Menendez, Goulven Monnier, Alexis Mouche, Frédéric Nouguier, George Nurser, Pierre Rampal, Ad Reniers, Ernesto Rodriguez, Justin Stopa, Céline Tison, Clément Ubelmann, Erik van Sebille, and Jiping Xie
Ocean Sci., 14, 337–354, https://doi.org/10.5194/os-14-337-2018, https://doi.org/10.5194/os-14-337-2018, 2018
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The Sea surface KInematics Multiscale (SKIM) monitoring mission is a proposal for a future satellite that is designed to measure ocean currents and waves. Using a Doppler radar, the accurate measurement of currents requires the removal of the mean velocity due to ocean wave motions. This paper describes the main processing steps needed to produce currents and wave data from the radar measurements. With this technique, SKIM can provide unprecedented coverage and resolution, over the global ocean.
Graham D. Quartly, Jean-François Legeais, Michaël Ablain, Lionel Zawadzki, M. Joana Fernandes, Sergei Rudenko, Loren Carrère, Pablo Nilo García, Paolo Cipollini, Ole B. Andersen, Jean-Christophe Poisson, Sabrina Mbajon Njiche, Anny Cazenave, and Jérôme Benveniste
Earth Syst. Sci. Data, 9, 557–572, https://doi.org/10.5194/essd-9-557-2017, https://doi.org/10.5194/essd-9-557-2017, 2017
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We have produced an improved monthly record of mean sea level for 1993–2015. It is developed by careful processing of the records from nine satellite altimeter missions, making use of the best available orbits, instrumental corrections and geophysical corrections. This paper details the selection process and the processing method. The data are suitable for investigation of sea level changes at scales from seasonal to long-term sea level rise, including interannual variations due to El Niño.
Marie-Isabelle Pujol, Yannice Faugère, Guillaume Taburet, Stéphanie Dupuy, Camille Pelloquin, Michael Ablain, and Nicolas Picot
Ocean Sci., 12, 1067–1090, https://doi.org/10.5194/os-12-1067-2016, https://doi.org/10.5194/os-12-1067-2016, 2016
Loren Carrere, Yannice Faugère, and Michaël Ablain
Ocean Sci., 12, 825–842, https://doi.org/10.5194/os-12-825-2016, https://doi.org/10.5194/os-12-825-2016, 2016
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New dynamic atmospheric (DAC_ERA) and dry tropospheric (DT_ERA) correction have been computed for the altimeter period using the ERA-Interim meteorological reanalysis. The corrections improve sea level estimations in Southern Ocean and in shallow waters; the impact is the most important for the first decade of altimetry, when operational meteorological models had a weaker quality. DT_ERA remains better in the recent period. New corrections significantly impact long-term regional trends.
Lionel Zawadzki, Michaël Ablain, Loren Carrere, Richard D. Ray, Nikita P. Zelensky, Florent Lyard, Amandine Guillot, and Nicolas Picot
Ocean Sci. Discuss., https://doi.org/10.5194/os-2016-19, https://doi.org/10.5194/os-2016-19, 2016
Preprint withdrawn
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Mean sea level (MSL) is a prominent indicator of climatic change, and is therefore of great scientific and societal interest. Since the beginning of the altimeter mission TOPEX/Poseidon and its successors Jason-1 and Jason-2, MSL products became essential for climate applications. Since 1995, a suspicious signal is apparent in the corresponding MSL record. Since 2010, scientific teams have been working on reducing this error. This paper assesses, characterizes and quantifies this reduction.
M. Ballarotta, F. Roquet, S. Falahat, Q. Zhang, and G. Madec
Clim. Past Discuss., https://doi.org/10.5194/cpd-11-3597-2015, https://doi.org/10.5194/cpd-11-3597-2015, 2015
Revised manuscript not accepted
Short summary
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We investigate the impact of the ocean geothermal heating (OGH) on a glacial ocean state using numerical simulations. We found that the OGH is a significant forcing of the abyssal ocean and thermohaline circulation. Applying the OGH warms the Antarctic Bottom Water by ~0.4°C and strengthens the deep circulation by 15% to 30%. The geothermally heated waters are advected from the Indo-Pacific to the North Atlantic basin, indirectly favouring the deep convection in the North Atlantic.
M. Ballarotta, S. Falahat, L. Brodeau, and K. Döös
Ocean Sci., 10, 907–921, https://doi.org/10.5194/os-10-907-2014, https://doi.org/10.5194/os-10-907-2014, 2014
M. Ballarotta, L. Brodeau, J. Brandefelt, P. Lundberg, and K. Döös
Clim. Past, 9, 2669–2686, https://doi.org/10.5194/cp-9-2669-2013, https://doi.org/10.5194/cp-9-2669-2013, 2013
C. Maraldi, J. Chanut, B. Levier, N. Ayoub, P. De Mey, G. Reffray, F. Lyard, S. Cailleau, M. Drévillon, E. A. Fanjul, M. G. Sotillo, P. Marsaleix, and the Mercator Research and Development Team
Ocean Sci., 9, 745–771, https://doi.org/10.5194/os-9-745-2013, https://doi.org/10.5194/os-9-745-2013, 2013
M. Ballarotta, L. Brodeau, J. Brandefelt, P. Lundberg, and K. Döös
Clim. Past Discuss., https://doi.org/10.5194/cpd-9-297-2013, https://doi.org/10.5194/cpd-9-297-2013, 2013
Revised manuscript has not been submitted
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Short summary
The signature of internal tides has become an important component for high-resolution altimetry over oceans. Several studies have proposed some solutions to resolve part of these internal tides based on the altimetry record. Following these studies, we propose here a new inversion approach aimed to mitigate aliasing with other dynamics. After a description of the methodology, the solution for the main tidal components has been successfully validated against independent observations.
The signature of internal tides has become an important component for high-resolution altimetry...
