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15. Physical processes in the upwelling regions of the tropical Atlantic

Author

Brandt, Peter, primary, Alory, Gaël, additional, Awo, Founi Mesmin, additional, Dengler, Marcus, additional, Djakouré, Sandrine, additional, Imbol Koungue, Rodrigue Anicet, additional, Jouanno, Julien, additional, Körner, Mareike, additional, Roch, Marisa, additional, and Rouault, Mathieu, additional

Published
2022
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21. Physical processes and biological productivity in the upwelling regions of the tropical Atlantic.

Author

Brandt, Peter, Alory, Gaël, Awo, Founi Mesmin, Dengler, Marcus, Djakouré, Sandrine, Imbol Koungue, Rodrigue Anicet, Jouanno, Julien, Körner, Mareike, Roch, Marisa, and Rouault, Mathieu

Subjects
BIOLOGICAL productivity, UPWELLING (Oceanography), TURBULENT mixing, WIND pressure, COASTS, HEAT flux
Abstract

In this paper, we review observational and modelling results on the upwelling in the tropical Atlantic between 10 ∘ N and 20 ∘ S. We focus on the physical processes that drive the seasonal variability of surface cooling and the upward nutrient flux required to explain the seasonality of biological productivity. We separately consider the equatorial upwelling system, the coastal upwelling system of the Gulf of Guinea and the tropical Angolan upwelling system. All three tropical Atlantic upwelling systems have in common a strong seasonal cycle, with peak biological productivity during boreal summer. However, the physical processes driving the upwelling vary between the three systems. For the equatorial regime, we discuss the wind forcing of upwelling velocity and turbulent mixing, as well as the underlying dynamics responsible for thermocline movements and current structure. The coastal upwelling system in the Gulf of Guinea is located along its northern boundary and is driven by both local and remote forcing. Particular emphasis is placed on the Guinea Current, its separation from the coast and the shape of the coastline. For the tropical Angolan upwelling, we show that this system is not driven by local winds but instead results from the combined effect of coastally trapped waves, surface heat and freshwater fluxes, and turbulent mixing. Finally, we review recent changes in the upwelling systems associated with climate variability and global warming and address possible responses of upwelling systems in future scenarios. [ABSTRACT FROM AUTHOR]

Published
2023
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22. Toward a probabilistic assessment of the global ocean response to fully-varying river runoffs

Author

Penduff, Thierry, Leroux, Stephanie, Llovel, William, Molines, Jean-Marc, Vialard, Jerome, Lengaigne, Matthieu, Tajouri, Soumaia, Sevellec, Florian, Jouanno, Julien, Papa, Fabrice, and De Boyer Montegut, Clement

Abstract

The main goal of the IMHOTEP OST-ST project is to investigate the response of the global ocean to fully-varying freshwater discharges from rivers and from the Greenland ice sheet between 1980 and 2018. This response concerns sea surface salinity (SSS), regional sea surface height (SSH) and its manometric/steric components, heat and freshwater contents, water mass properties, regional to basin-scale circulation, etc. We are currently analyzing satellite/in-situ observations and the outputs from a recent series of NEMO-based global ocean/sea-ice/iceberg 1/4° simulations where runoffs are individually set to climatological and fully-variable in various source regions. The JRA55 fully-variable atmospheric forcing is applied in all simulations without any SSS relaxation, which is replaced by a precipitation correction term that lets salinity free to evolve. Daily river discharge forcing data were derived from the ISBA-CTRIP hydrological reanalysis, and monthly (solid and liquid) freshwater discharges from Greenland are derived from satellite altimetry data (SAR mode) combined with regional climate simulations (Mouginot et al., 2019). Special attention was dedicated to the bathymetry and the partitionning between solid and liquid discharges all around Greenland, in order to realistically feed icebergs and freshwater plumes. This presentation is focused on the interannual variability and 40-year trends of SSS in response to fluctuating runoffs at global scale, based on 5 simulations and a comparison to an ESA L4 product merging SMOS, Aquarius and SMAP SSS data (Boutin et al., 2021). Results show that the simulated SSS interannual variability compares well with observations. River runoffs directly force interannual SSS variability which can reach 0.5 to 0.75 g/kg in specific regions (Amazon plume, Siberian coast, Maritime Continent, China river mouths, etc) and about 0.2 g/kg along many coasts, with substantial penetration into the open ocean in several regions. Substantial (positive or negative) 40-year trends in the runoffs of key rivers also have a direct impact on regional SSS trends, which exhibit substantial freshening trends off Siberian coasts and throughout the Maritime Continent, and salinization off the equatorial African west coast in particular. These first results also suggest that SSS interannual variability is primarily driven by atmospheric and runoff fluctuations; this is quite different for the interannual variability of SSH and of many other oceanic climate indices, which are strongly impacted by chaotic intrinsic variability (CIV) in addition to the former two external drivers. Assessing the interannual response of these latter oceanic fields to fluctuating runoffs thus require an attenuation of this low-frequency CIV, which in turn requires ensemble ocean simulations with slightly different initial states (as done during the OCCIPUT project, https://meom-group.github.io/projects/occiput/). The IMHOTEP project team will perform in 2022 two 10-member ensembles of global ocean/sea-ice 1/4° simulations driven by the same JRA55 forcing, one ensemble with climatological and one without interannually-varying runoffs: comparing the fluctuations of ensemble means of key variables will allow a more complete analysis of the multivariate and multi-scale response of the ocean to fluctuating runoffs, regardless of CIV. These analyses will provide direct insight for the interpretation of signals observed by satellite and in situ platforms, and their attribution to distinct drivers.

Published
2022
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26. Physical processes in the upwelling regions of the tropical Atlantic.

Author

Brandt, Peter, Alory, Gaël, Awo, Founi Mesmin, Dengler, Marcus, Djakouré, Sandrine, Koungue, Rodrigue Anicet Imbol, Jouanno, Julien, Körner, Mareike, Roch, Marisa, and Rouault, Mathieu

Subjects
UPWELLING (Oceanography), SURFACE cooling, TURBULENT mixing, PRIMARY commodities
Abstract

In this paper, we review observational and modelling results on the upwelling in the inner tropical Atlantic. We focus on the physical processes that drive the seasonal variability of surface cooling and upward nutrient flux required to explain the seasonality of primary productivity. We separately consider the equatorial upwelling system, the northern coastal upwelling system of the Gulf of Guinea and the tropical Angolan upwelling system. For the equatorial regime, we discuss the forcing of upwelling velocity and turbulent mixing as well as the underlying dynamics responsible for thermocline movements and current structure. The coastal upwelling system in the Gulf of Guinea is concentrated along northern boundary and is driven by both, local and remote forcing. The particular role of the Guinea Current, nonlinearity and the shape of the coastline are emphasized. For the tropical Angolan upwelling, we show that this system is not wind-driven, but instead results from the combined effect of coastally trapped waves, surface heat and freshwater fluxes, and turbulent mixing. Finally, we review recent changes in the upwelling systems associated with climate variability and global warming and address possible responses of upwelling systems in future scenarios. [ABSTRACT FROM AUTHOR]

Published
2022
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27. Joint observation-model mixed-layer heat and salt budgets in the eastern tropical Atlantic.

Author

Ngakala, Roy Dorgeless, Alory, Gael, Da-Allada, Casimir Yélognissè, Kom, Olivia Estelle, Jouanno, Julien, Rath, Willi, and Baloïtcha, Ezinvi

Subjects
ADVECTION, HEAT flux, ATMOSPHERIC temperature, SALINITY
Abstract

In this study, we use a joint observation-model approach to investigate the mixed-layer heat and salt annual mean and seasonal budgets in the eastern tropical Atlantic. The regional PREFCLIM observational climatology provides the budget terms with a relatively low spatial and temporal resolution compared to the online NEMO model, and this later is then re-sampled as in PREFCLIM climatology. In addition, advection terms are recomputed offline from the model as PREFCLIM gridded advection computation. In Senegal, Angola and Benguela regions, the seasonal cycle of mixed-layer temperature is mainly governed by surface heat fluxes; however, it is essentially driven by vertical heat diffusion in Equatorial region. The seasonal cycle of mixed-layer salinity is largely controlled by freshwater flux in Senegal and Benguela regions; however, it follows the variability of zonal and meridional salt advection in Equatorial and Angola regions respectively. Our results show that the time-averaged spatial distribution of NEMO offline heat/salt advection terms compares much better to PREFCLIM horizontal advection terms than the online heat/salt advection terms. However, the seasonal cycle of horizontal advection in selected regions shows that NEMO offline terms do not always compare well with PREFCLIM, sometimes less than online terms. Despite this difference, these results suggest the important role of small scale variability in mixed-layer heat and salt budgets. [ABSTRACT FROM AUTHOR]

Published
2022
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30. A NEMO-based model of <i>Sargassum</i> distribution in the tropical Atlantic: description of the model and sensitivity analysis (NEMO-Sarg1.0)

Author

Jouanno, Julien, primary, Benshila, Rachid, additional, Berline, Léo, additional, Soulié, Antonin, additional, Radenac, Marie-Hélène, additional, Morvan, Guillaume, additional, Diaz, Frédéric, additional, Sheinbaum, Julio, additional, Chevalier, Cristele, additional, Thibaut, Thierry, additional, Changeux, Thomas, additional, Menard, Frédéric, additional, Berthet, Sarah, additional, Aumont, Olivier, additional, Ethé, Christian, additional, Nabat, Pierre, additional, and Mallet, Marc, additional

Published
2021
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33. How does the phytoplankton-light feedback affect marine N2O inventory?

Author

Berthet, Sarah, Jouanno, Julien, Séférian, Roland, Gehlen, Marion, and Llovel, William

Subjects
*NITROUS oxide, *SEAWATER, *SEA ice, *CONCENTRATION functions, *ATMOSPHERIC models, *OCEAN waves, *BIOGEOCHEMISTRY
Abstract

The phytoplankton-light feedback (PLF) depicts how phytoplankton biomass interacts with the downwelling shortwave radiation entering the ocean. Considering the PLF allows differential heating across the ocean water column as a function of the phytoplankton concentration. Only one third of the CMIP6 Earth system models include a complete representation of the PLF. In other models, the PLF is mimicked either thanks to a prescribed climatology of chlorophyll or not represented at all. Consequences of an incomplete representation of the PLF on the marine biogeochemical content haven't been assessed yet and remain a source of multi-model uncertainty in future projection. Here, we scrutinize with a single modelling set-up how various representation of the PLF can impact ocean physics and ultimately marine production of a major greenhouse gas, the nitrous oxide (N2O). Global sensitivity experiments considering the ocean, sea ice and marine biogeochemistry have been performed at 1-degree of horizontal resolution over the last two decades (1999-2018). We show that the representation of the PLF has significant consequences on the ocean heat uptake and temperature of the first 300 meters of the tropical ocean. Temperature anomalies due to an incomplete PLF representation drive perturbations of the ocean stratification, dynamics and oxygen concentration. Different projection pathways for N2O production result from the choice of the PLF representation. Considering an incomplete representation of the PLF overestimates the oxygen concentration the North-Pacific oxygen minimum zone and underestimates the local N2O production. This leads to important regional differences of sea-to-air N2O fluxes: fluxes are enhanced by up to 24% in the south Pacific and south Atlantic subtropical gyres, but reduced by up to 12% in oxygen minimum zones of the northern hemisphere. Our results based on a global ocean biogeochemical model at CMIP6 state-of-the-art thus shine a light on a current uncertainty of the modelled marine nitrous oxide budget in that climate models. [ABSTRACT FROM AUTHOR]

Published
2022
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35. Connecting flow–topography interactions, vorticity balance, baroclinic instability and transport in the Southern Ocean: the case of an idealized storm track

Author

Jouanno, Julien, Capet, X., Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Processus et interactions de fine échelle océanique (PROTEO), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU), ANR-11-JS56-0009,SMOC,Modélisation de la sousmésoechelle océanique pour une meilleure compréhension du climat(2011), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
lcsh:GE1-350, lcsh:G, 13. Climate action, lcsh:Geography. Anthropology. Recreation, 14. Life underwater, lcsh:Environmental sciences, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography
Abstract

International audience; The dynamical balance of the Antarctic Circum-polar 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. The classical partition between barotropic and baroclinic modes is sensitive to current-topography interactions in the mesoscale range 10-100 km, as comparisons between simulations with rough or smooth bathymetry reveal. Configurations with a rough bottom have weak barotropic motions, ubiquitous bottom form stress/pressure torque, no wind-driven gyre in the lee of topographic ridges, less efficient baroclinic turbulence and, thus, larger circumpolar transport rates. The difference in circumpolar transport produced by topographic roughness depends on the strength with which (external) thermohaline forcings by the rest of the world ocean constrain the strat-ification at the northern edge of the SO. The study highlights the need for a more comprehensive treatment of the Antarctic Circumpolar Current (ACC) interactions with the ocean floor, including realistic fields of bottom form stress and pressure torque. It also sheds some light on the behavior of idealized storm tracks recently modeled: (i) the saturation mechanism, whereby the circumpolar transport does not depend on wind intensity, is a robust and generic attribute of ACC-like circumpolar flows; (ii) the adjustment toward saturation can take place over widely different timescales (from months to years) depending on the possibility (or not) for barotropic Rossby waves to propagate signals of wind change and accelerate/decelerate SO wind-driven gyres. The real SO having both gyres and ACC saturation timescales typical of our "no gyre" simulations may be in an intermediate regime in which mesoscale topography away from major ridges provides partial and localized support for bottom form stress/pressure torque.

Published
2020

37. Use of 223Ra and 224Ra as chronometers to estimate the residence time of Amazon waters on the Brazilian continental shelf.

Author

Léon, Morgane, van Beek, Pieter, Scholten, Jan, Moore, Willard S., Souhaut, Marc, De Oliveira, Joselene, Jeandel, Catherine, Seyler, Patrick, and Jouanno, Julien

Subjects
CONTINENTAL shelf, RADIUM isotopes, REGIONS of freshwater influence, CHRONOMETERS, OCEAN dynamics
Abstract

When rivers mix into the ocean, radium isotopes are released into the dissolved phase allowing us to apply these isotopes as powerful tracers of river plumes spreading into the ocean. We report 223Ra and 224Ra radium activities that were determined in the Amazon River mouth and along the Amazon plume that extends off the coasts of Brazil and French Guyana into the Atlantic Ocean. We summarize 223Ra and 224Ra data from AmasSeds (1991), AMANDES (GEOTRACES process study GApr01; 2007–2008) and M147 (2018) projects, which were conducted in different seasons corresponding to different Amazon discharge rates. We determined the 224Raex/223Ra activity ratios (AR) along the Amazon plume to derive apparent ages and to estimate the residence time of the Amazon waters on the Brazilian continental shelf. Our data suggest that it takes 9–14 d for the Amazon waters to reach the northern continental shelf off French Guyana and 12–21 d to reach the eastern part of the Brazilian continental shelf. These time scales are in good agreement with those derived from a high‐resolution numerical simulation of the regional ocean dynamics. We do not find any relationship between the discharge rate of the Amazon River and the residence time of the waters on the Brazilian continental shelf, suggesting that the residence time of the Amazon waters is primarily driven by the ambient northwestward current. Using the apparent ages along the plume, we estimate an average velocity of 26 cm s−1 for the northward transport of the Amazon waters on the continental shelf. [ABSTRACT FROM AUTHOR]

Published
2022
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41. From Mixing to the Large Scale Circulation: How the Inverse Cascade Is Involved in the Formation of the Subsurface Currents in the Gulf of Guinea.

Author

Assene, Fernand, primary, Morel, Yves, additional, Delpech, Audrey, additional, Aguedjou, Micael, additional, Jouanno, Julien, additional, Cravatte, Sophie, additional, Marin, Frédéric, additional, Ménesguen, Claire, additional, Chaigneau, Alexis, additional, Dadou, Isabelle, additional, Alory, Gael, additional, Holmes, Ryan, additional, Bourlès, Bernard, additional, and Koch-Larrouy, Ariane, additional

Published
2021
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42. A NEMO-based model of Sargassum distribution in the Tropical Atlantic 

Author

Benshila, Rachid, primary, Jouanno, Julien, additional, Berline, Léo, additional, Soulié, Antonin, additional, Marie-Hélène, Marie-Hélène, additional, Morvan, Guillaume, additional, Diaz, Frédéric, additional, Sheinbaum, Julio, additional, Chevalier, Cristele, additional, Thibaut, Thierry, additional, Changeux, Thomas, additional, Menard, Frédéric, additional, Berthet, Sarah, additional, Aumont, Olivier, additional, Ethé, Christian, additional, Nabat, Pierre, additional, and Mallet, Marc, additional

Published
2021
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43. Evolution of the riverine nutrient export to the Tropical Atlantic over the last 15 years: is there a link with Sargassum proliferation?

Author

Jouanno, Julien, primary, Moquet, Jean-Sébastien, additional, Berline, Léo, additional, Radenac, Marie-Hélène, additional, Santini, William, additional, Changeux, Thomas, additional, Thibaut, Thierry, additional, Podlejski, Witold, additional, Ménard, Frédéric, additional, Martinez, Jean-Michel, additional, Aumont, Olivier, additional, Sheinbaum, Julio, additional, Filizola, Naziano, additional, and Moukandi N’Kaya, Guy Dieudonne, additional

Published
2021
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46. Erosion of the subsurface salinity maximum of the loop current eddies from glider observations and a numerical model

Author

Sosa-Gutierrez, R., Pallas-Sanz, E., Jouanno, Julien, Chaigneau, Alexis, Candela, J., and Tenreiro, M.

Subjects
Loop Current Eddies, Northern winds, Caribbean Subtropical UnderWater, salt budget, vertical salinity diffusion, negative net heat fluxes
Abstract

The erosion of the subsurface salinity maximum, signature of the Caribbean Subtropical UnderWater (SUW), within the Loop Current Eddy (LCE) Poseidon (August 2016 to July 2017) in the Gulf of Mexico (GoM) and the formation of the Gulf Common Water (GCW) during its journey westward, was observed using glider data. Most of the dilution of the SUW high-salinity core within Poseidon occurs during late autumn and winter associated withNorthernwinds and mixed-layer deepening. The physical processes that contribute to salt dilution of the SUW inside the LCEs' core are investigated using a numerical regional model. The analysis of the salt budget in a long-lasting numerical LCE and a composite analysis of sixteen LCEs reveal that the salinity trend is mostly explained by the vertical salinity diffusion. Cold and dryNorthernwinds during the first winter drive strong negative net heat fluxes that trigger turbulent flux of salt into the LCEs' thermostad and dilution of the SUW high-salinity core below. The vertical salinity diffusion continues homogenizing the salinity in the upper ocean until the vertical gradient of salinity is negligible. As a result, SUW is transformed to precursor of GCW that is ultimately diffused to surrounding waters in the western GoM. Although the contribution of advection to the salinity trend above the isopycnal of 1,026 kg m(-3)is of second order, below is the most important process driving loss of salinity, presumably due to, eddy-eddy interactions during LCEs' westward propagation and eddy pumping (upwelling) during the LCEs' decaying phase along the western slope.

Published
2020

47. A NEMO-based model of <i>Sargassum</i> distribution in the Tropical Atlantic: description of the model and sensitivity analysis (NEMO-Sarg1.0)

Author

Jouanno, Julien, primary, Benshila, Rachid, additional, Berline, Léo, additional, Soulié, Antonin, additional, Radenac, Marie-Hélène, additional, Morvan, Guillaume, additional, Diaz, Frédéric, additional, Sheinbaum, Julio, additional, Chevalier, Cristele, additional, Thibaut, Thierry, additional, Changeux, Thomas, additional, Menard, Frédéric, additional, Berthet, Sarah, additional, Aumont, Olivier, additional, Ethé, Christian, additional, Nabat, Pierre, additional, and Mallet, Marc, additional

Published
2020
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48. From Mixing to the Large Scale Circulation: How the Inverse Cascade Is Involved in the Formation of the Subsurface Currents in the Gulf of Guinea

Author

Assene, Fernand, primary, Morel, Yves, additional, Delpech, Audrey, additional, Aguedjou, Micael, additional, Jouanno, Julien, additional, Cravatte, Sophie, additional, Marin, Frédéric, additional, Ménesguen, Claire, additional, Chaigneau, Alexis, additional, Dadou, Isabelle, additional, Alory, Gael, additional, Holmes, Ryan, additional, Bourlès, Bernard, additional, and Koch-Larrouy, Ariane, additional

Published
2020
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