Articles | Volume 22, issue 2
https://doi.org/10.5194/os-22-871-2026
© 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/os-22-871-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Mar 2026
Research article |
| 19 Mar 2026
| 19 Mar 2026
Tidal signatures on surface chlorophyll a concentration in the Brazilian Equatorial Margin
Carina Regina de Macedo
CORRESPONDING AUTHOR
Earth Observation and Geoinformatics Division, General Coordination of Earth Sciences, National Institute for Space Research (INPE), São José dos Campos, Brazil
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
LEGOS CNRS/IRD/CNES, Université de Toulouse, Toulouse, France
Ariane Koch-Larrouy
LEGOS CNRS/IRD/CNES, Université de Toulouse, Toulouse, France
CECI CNRS/Cerfacs/IRD, Université de Toulouse, Toulouse, France
José Carlos Bastos da Silva
Department of Geosciences, Environment and Spatial Planning, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal
Instituto de Ciências da Terra, Polo Porto, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal
Jorge Manuel Magalhães
Department of Geosciences, Environment and Spatial Planning, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal
CIIMAR, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal
Fernand Assene
Department of Maritime Navigation and Information Systems, National Advanced School of Maritime and Ocean Science and Technology (NASMOST), University of Ebolowa, P.O. Box: 292 Kribi, Ebolowa, Cameroon
Manh Duy Tran
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
Isabelle Dadou
LEGOS CNRS/IRD/CNES, Université de Toulouse, Toulouse, France
Amine M'Hamdi
LEGOS CNRS/IRD/CNES, Université de Toulouse, Toulouse, France
CECI CNRS/Cerfacs/IRD, Université de Toulouse, Toulouse, France
Departamento de Oceanografia da Universidade Federal de Pernambuco – DOCEAN/UFPE, Recife, Brazil
Trung Kien Tran
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
Vincent Vantrepotte
Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, UMR 8187 – LOG – Laboratoire d'Océanologie et de Géosciences, 62930 Wimereux, France
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Twin simulations, with and without tides, are used to assess the impact of internal tides (ITs) on ocean temperature off the Amazon mouth at a seasonal scale. We found that in the surface layers, ITs and barotropic tides cause a cooling effect on sea surface temperature, subsequently leading to an increase in the net heat flux between the atmosphere and ocean. Vertical mixing is identified as the primary driver, followed by vertical and horizontal advection.
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Ocean Sci., 19, 1357–1374, https://doi.org/10.5194/os-19-1357-2023, https://doi.org/10.5194/os-19-1357-2023, 2023
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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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Short summary
We investigated how ocean tides influence marine phytoplankton along the North Brazilian coast. Using satellite data from 2005 to 2021, we found that tides can either enhance or reduce phytoplankton growth on the continental shelf. Offshore, internal tides stimulate primary production along their pathways. These results improve our understanding of how tidal processes shape marine life in tropical coastal regions.
We investigated how ocean tides influence marine phytoplankton along the North Brazilian coast....
