Articles | Volume 19, issue 3
https://doi.org/10.5194/os-19-535-2023
© Author(s) 2023. 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-19-535-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 May 2023
Research article |
| 05 May 2023
| 05 May 2023
Joint observation–model mixed-layer heat and salt budgets in the eastern tropical Atlantic
Roy Dorgeless Ngakala
CORRESPONDING AUTHOR
Department of Oceanography and Applications, International Chair in
Mathematical Physics and Applications, University of Abomey-Calavi, Cotonou,
Benin
Department of Oceanography and Environment, Institut National de
Recherche en Sciences Exactes et Naturelles, Pointe-Noire, Congo
Gaël Alory
Laboratoire d'Etudes en Géophysique et Océanographie
Spatiales, University of Toulouse, Toulouse, France
Casimir Yélognissè Da-Allada
Department of Oceanography and Applications, International Chair in
Mathematical Physics and Applications, University of Abomey-Calavi, Cotonou,
Benin
Laboratoire de Géosciences, de l'Environnement et Applications,
Université Nationale des Sciences Technologies, Ingénierie et
Mathématiques, Abomey, Benin
Laboratoire d'Hydrologie Marine et Côtière, Institut de
Recherches Halieutiques et Océanologiques du Bénin, Cotonou, Benin
Olivia Estelle Kom
Department of Oceanography and Applications, International Chair in
Mathematical Physics and Applications, University of Abomey-Calavi, Cotonou,
Benin
Julien Jouanno
Laboratoire d'Etudes en Géophysique et Océanographie
Spatiales, University of Toulouse, Toulouse, France
Willi Rath
GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, Kiel, Germany
Ezinvi Baloïtcha
Department of Oceanography and Applications, International Chair in
Mathematical Physics and Applications, University of Abomey-Calavi, Cotonou,
Benin
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Peter Brandt, Gaël Alory, Founi Mesmin Awo, Marcus Dengler, Sandrine Djakouré, Rodrigue Anicet Imbol Koungue, Julien Jouanno, Mareike Körner, Marisa Roch, and Mathieu Rouault
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Sarah Berthet, Julien Jouanno, Roland Séférian, Marion Gehlen, and William Llovel
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Alan D. Fox, Patricia Handmann, Christina Schmidt, Neil Fraser, Siren Rühs, Alejandra Sanchez-Franks, Torge Martin, Marilena Oltmanns, Clare Johnson, Willi Rath, N. Penny Holliday, Arne Biastoch, Stuart A. Cunningham, and Igor Yashayaev
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Pierre Damien, Julio Sheinbaum, Orens Pasqueron de Fommervault, Julien Jouanno, Lorena Linacre, and Olaf Duteil
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Julien Jouanno, Rachid Benshila, Léo Berline, Antonin Soulié, Marie-Hélène Radenac, Guillaume Morvan, Frédéric Diaz, Julio Sheinbaum, Cristele Chevalier, Thierry Thibaut, Thomas Changeux, Frédéric Menard, Sarah Berthet, Olivier Aumont, Christian Ethé, Pierre Nabat, and Marc Mallet
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Julien Jouanno and Xavier Capet
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The dynamical balance of the Antarctic Circumpolar Current and its implications on the functioning of the world ocean are not fully understood and poorly represented in global circulation models. In this study, the sensitivities of an idealized Southern Ocean (SO) storm track are explored with a set of eddy-rich numerical simulations. We show that the classical partition between barotropic and baroclinic modes is sensitive to current–topography interactions in the mesoscale range of 10–100 km.
Katja Matthes, Arne Biastoch, Sebastian Wahl, Jan Harlaß, Torge Martin, Tim Brücher, Annika Drews, Dana Ehlert, Klaus Getzlaff, Fritz Krüger, Willi Rath, Markus Scheinert, Franziska U. Schwarzkopf, Tobias Bayr, Hauke Schmidt, and Wonsun Park
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A new Earth system model, the Flexible Ocean and Climate Infrastructure (FOCI), is introduced, consisting of a high-top atmosphere, an ocean model, sea-ice and land surface model components. A unique feature of FOCI is the ability to explicitly resolve small-scale oceanic features, for example, the Agulhas Current and the Gulf Stream. It allows to study the evolution of the climate system on regional and seasonal to (multi)decadal scales and bridges the gap to coarse-resolution climate models.
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The currents along the West African seaboard are poorly known. Based on a carefully evaluated numerical simulation the present study describes these currents in the sector 8–20°N and the physical processes that drive them. Prevailing northward flow with two intensification periods per year is identified. Both local and distant coastal winds (blowing as far as thousands of kilometers away in the Gulf of Guinea) contribute to the circulation in this sector.
Gilles Reverdin, Hedinn Valdimarsson, Gael Alory, Denis Diverres, Francis Bringas, Gustavo Goni, Lars Heilmann, Leon Chafik, Tanguy Szekely, and Andrew R. Friedman
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We report monthly time series of surface temperature, salinity, and density in the North Atlantic subpolar gyre in 1993–2017 from hydrographical data collected in particular from thermosalinographs onboard selected ships of opportunity. Most of the time, this data set reproduces well the large-scale variability, except for a few seasons with limited sampling, in particular in winter along western Greenland or northeast of Newfoundland in the presence of sea ice.
Julien Jouanno, Olga Hernandez, and Emilia Sanchez-Gomez
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Julien Jouanno, Xavier Capet, Gurvan Madec, Guillaume Roullet, and Patrice Klein
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The aim of this study is to clarify the role of the Southern Ocean storms on interior mixing and meridional overturning circulation. A periodic and idealized configuration of the NEMO model has been designed to represent the key physical processes of a zonal portion of the Southern Ocean. Challenging issues concerning how numerical models are able to represent interior mixing forced by high-frequency winds are exposed and discussed, particularly in the context of the overturning circulation.
S. C. Kenfack, K. F. Mkankam, G. Alory, Y. du Penhoat, N. M. Hounkonnou, D. A. Vondou, and G. N. Bawe
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Revised manuscript not accepted
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Short summary
Surface heat flux is the main driver of the heat budget in the Senegal, Angola, and Benguela regions but not in the equatorial region. In the Senegal and Benguela regions, freshwater flux governs the salt budget, while in equatorial and Angola regions, oceanic processes are the main drivers. Results from numerical simulation show the important role of mesoscale advection for temperature and salinity variations in the mixed layer. Nonlinear processes unresolved by observations play a key role.
Surface heat flux is the main driver of the heat budget in the Senegal, Angola, and Benguela...
