Articles | Volume 21, issue 6
https://doi.org/10.5194/os-21-2873-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/os-21-2873-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Nov 2025
Research article |
| 11 Nov 2025
| 11 Nov 2025
Impact of internal tides on chlorophyll a distribution and primary production off the Amazon shelf from glider measurements and satellite observations
LEGOS, Université de Toulouse, CNRS, OMP, IRD, Toulouse, France
Departamento de Oceanografia, Universidade Federal de Pernambuco (DOCEAN/UFPE), Recife, Brazil
CECI CNRS/Cerfacs/IRD, Université de Toulouse, Toulouse, France
Ariane Koch-Larrouy
LEGOS, Université de Toulouse, CNRS, OMP, IRD, Toulouse, France
CECI CNRS/Cerfacs/IRD, Université de Toulouse, Toulouse, France
Alex Costa da Silva
Departamento de Oceanografia, Universidade Federal de Pernambuco (DOCEAN/UFPE), Recife, Brazil
Isabelle Dadou
LEGOS, Université de Toulouse, CNRS, OMP, IRD, Toulouse, France
Carina Regina de Macedo
LEGOS, Université de Toulouse, CNRS, OMP, IRD, Toulouse, France
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
Earth Observation and Geoinformatics Division, National Institute for Space Research (INPE), São José dos Campos, Brazil
Anthony Bosse
Mediterranean Institute of Oceanography, OSU Institut Pytheas, Aix Marseille University, Université de Toulon, CNRS, IRD, Marseille, France
Vincent Vantrepotte
Departamento de Oceanografia, Universidade Federal de Pernambuco (DOCEAN/UFPE), Recife, Brazil
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
Habib Micaël Aguedjou
LEGOS, Université de Toulouse, CNRS, OMP, IRD, Toulouse, France
Centre National d'Etudes Spatiales, 18 av. Edouard Belin, 31400 Tououse, France
Trung-Kien Tran
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
Pierre Testor
LOCEAN-IPSL/CNRS, Université Pierre et Marie Curie, T45-55 E4 case 100, 4 place Jussieu, 75252 Paris, France
Laurent Mortier
Ecole Nationale Supérieure de Techniques Avancées, 29 rue d'Ulm, CEDEX 05, 75230 Paris, France
Arnaud Bertrand
MARBEC, Université de Montpellier, CNRS, Ifremer, IRD, Sète, France
Pedro Augusto Mendes de Castro Melo
Departamento de Oceanografia, Universidade Federal de Pernambuco (DOCEAN/UFPE), Recife, Brazil
James Lee
Departamento de Oceanografia, Universidade Federal do Pará (UFPA), Belém, Brazil
Marcelo Rollnic
Departamento de Oceanografia, Universidade Federal do Pará (UFPA), Belém, Brazil
Moacyr Araujo
Departamento de Oceanografia, Universidade Federal de Pernambuco (DOCEAN/UFPE), Recife, Brazil
Brazilian Research Network on Global Climate Change (Rede CLIMA), 12227-010, São José dos Campos-SP, Brazil
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Caroline Ulses, Claude Estournel, Patrick Marsaleix, Karline Soetaert, Marine Fourrier, Laurent Coppola, Dominique Lefèvre, Franck Touratier, Catherine Goyet, Véronique Guglielmi, Fayçal Kessouri, Pierre Testor, and Xavier Durrieu de Madron
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Edward D. Zaron, Tonia A. Capuano, and Ariane Koch-Larrouy
Ocean Sci., 19, 43–55, https://doi.org/10.5194/os-19-43-2023, https://doi.org/10.5194/os-19-43-2023, 2023
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Stéphanie Barrillon, Robin Fuchs, Anne A. Petrenko, Caroline Comby, Anthony Bosse, Christophe Yohia, Jean-Luc Fuda, Nagib Bhairy, Frédéric Cyr, Andrea M. Doglioli, Gérald Grégori, Roxane Tzortzis, Francesco d'Ovidio, and Melilotus Thyssen
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Everton Giachini Tosetto, Arnaud Bertrand, Sigrid Neumann-Leitão, Alex Costa da Silva, and Miodeli Nogueira Júnior
Ocean Sci., 18, 1763–1779, https://doi.org/10.5194/os-18-1763-2022, https://doi.org/10.5194/os-18-1763-2022, 2022
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Saúl Edgardo Martínez Castellón, José Henrique Cattanio, José Francisco Berrêdo, Marcelo Rollnic, Maria de Lourdes Ruivo, and Carlos Noriega
Biogeosciences, 19, 5483–5497, https://doi.org/10.5194/bg-19-5483-2022, https://doi.org/10.5194/bg-19-5483-2022, 2022
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We seek to understand the influence of climatic seasonality and microtopography on CO2 and CH4 fluxes in an Amazonian mangrove. Topography and seasonality had a contrasting influence when comparing the two gas fluxes: CO2 fluxes were greater in high topography in the dry period, and CH4 fluxes were greater in the rainy season in low topography. Only CO2 fluxes were correlated with soil organic matter, the proportion of carbon and nitrogen, and redox potential.
Michel Tchilibou, Ariane Koch-Larrouy, Simon Barbot, Florent Lyard, Yves Morel, Julien Jouanno, and Rosemary Morrow
Ocean Sci., 18, 1591–1618, https://doi.org/10.5194/os-18-1591-2022, https://doi.org/10.5194/os-18-1591-2022, 2022
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This high-resolution model-based study investigates the variability in the generation, propagation, and sea height signature (SSH) of the internal tide off the Amazon shelf during two contrasted seasons. ITs propagate further north during the season characterized by weak currents and mesoscale eddies and a shallow and strong pycnocline. IT imprints on SSH dominate those of the geostrophic motion for horizontal scales below 200 km; moreover, the SSH is mainly incoherent below 70 km.
Katia Mallil, Pierre Testor, Anthony Bosse, Félix Margirier, Loic Houpert, Hervé Le Goff, Laurent Mortier, and Ferial Louanchi
Ocean Sci., 18, 937–952, https://doi.org/10.5194/os-18-937-2022, https://doi.org/10.5194/os-18-937-2022, 2022
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Our study documents the circulation in the Algerian Basin of the western Mediterranean Sea using in situ data. It shows that the Algerian Gyres have an impact on the distribution at intermediate depth of Levantine Intermediate Water. They allow a westward transport from the south of Sardinia toward the interior of the Algerian Basin. Temperature and salinity trends of this water mass are also investigated, confirming a recent acceleration of the warming and salinification during the last decade.
Ramilla Vieira Assunção, Anne Lebourges-Dhaussy, Alex Costa da Silva, Bernard Bourlès, Gary Vargas, Gildas Roudaut, and Arnaud Bertrand
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-101, https://doi.org/10.5194/os-2021-101, 2021
Publication in OS not foreseen
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Active acoustics has been used to characterize physical structures and processes in the ocean, typically attributed to biological dispersion or turbulent structures. We take advantage of acoustic data from the Southwest Atlantic to test the feasibility of this approach in an oligotrophic region. The results show that the thermohaline structure impacts the vertical distribution of acoustic scatterers, however the methods tested did not allow a robust estimate of the thermohaline limits.
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Short summary
In the ocean off the Amazon shelf, internal waves caused by tides move water layers up and down and mix them. Using an underwater glider and satellites, we found internal tides redistribute chlorophyll from the deep chlorophyll maximum upward to the surface and downward to depth. Turbulent chlorophyll fluxes supply about 38 % of surface chlorophyll, and total chlorophyll increases by 14–29 % during strong tides, potentially affecting the marine food web.
In the ocean off the Amazon shelf, internal waves caused by tides move water layers up and down...
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