Articles | Volume 19, issue 2
https://doi.org/10.5194/os-19-251-2023
© 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-19-251-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Revisiting the tropical Atlantic western boundary circulation from a 25-year time series of satellite altimetry data
Djoirka Minto Dimoune
CORRESPONDING AUTHOR
Departamento de Oceanografia da Universidade Federal de Pernambuco (UFPE), Laboratorio de Oceanografia Física Estuarina e Costeira (LOFEC), Cidade Universitária, Avenida Arquitetura s/n, 50740-550 Recife, PE,
Brazil
Nansen Tutu Center for Marine Environmental Research, Department of Oceanography, University of Cape Town, Rondebosch, Cape Town, 7700, South Africa
Florence Birol
LEGOS, Université de Toulouse, CNES, CNRS, IRD, 14 avenue Edouard
Belin, 31400 Toulouse, France
Fabrice Hernandez
Departamento de Oceanografia da Universidade Federal de Pernambuco (UFPE), Laboratorio de Oceanografia Física Estuarina e Costeira (LOFEC), Cidade Universitária, Avenida Arquitetura s/n, 50740-550 Recife, PE,
Brazil
LEGOS, Université de Toulouse, CNES, CNRS, IRD, 14 avenue Edouard
Belin, 31400 Toulouse, France
Fabien Léger
LEGOS, Université de Toulouse, CNES, CNRS, IRD, 14 avenue Edouard
Belin, 31400 Toulouse, France
Moacyr Araujo
Departamento de Oceanografia da Universidade Federal de Pernambuco (UFPE), Laboratorio de Oceanografia Física Estuarina e Costeira (LOFEC), Cidade Universitária, Avenida Arquitetura s/n, 50740-550 Recife, PE,
Brazil
Brazilian Research Network on Global Climate Change (Rede CLIMA), Av.
dos Astronautas, 1758, 01227-010 São José dos Campos, SP, Brazil
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Fabrice Hernandez, Marcos Garcia Sotillo, and Angelique Melet
State Planet Discuss., https://doi.org/10.5194/sp-2024-39, https://doi.org/10.5194/sp-2024-39, 2024
Preprint under review for SP
Short summary
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An historical review over the last three decades on intercomparison projects of ocean numerical reanalysis or forecast is first proposed. From this, main issues and lessons learned are discussed in order to propose an overview of best practices and key considerations to facilitate intercomparison activities in operational oceanography.
Marcos G. Sotillo, Marie Drevillon, and Fabrice Hernandez
State Planet Discuss., https://doi.org/10.5194/sp-2024-33, https://doi.org/10.5194/sp-2024-33, 2024
Preprint under review for SP
Short summary
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Operational forecasting systems requires best practices for assessing the quality of ocean products. The Authors discusses on the role of observing network for performing validation of ocean models, identifying current gaps, but also emphasizing the need of new metrics. An analysis on the level of maturity of validation processes from global to regional systems is provided. A rich variety of approaches exists. Example of Copernicus Marine product quality organization is provided.
Fabius Kouogang, Ariane Koch-Larrouy, Jorge Magalhaes, Alex Costa da Silva, Daphne Kerhervé, Arnaud Bertrand, Evan Cervelli, Jean-François Ternon, Pierre Rousselot, James Lee, Marcelo Rollnic, and Moacyr Araujo
EGUsphere, https://doi.org/10.5194/egusphere-2024-2548, https://doi.org/10.5194/egusphere-2024-2548, 2024
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The first time direct measurements of turbulent dissipation from AMAZOMIX revealed high energy dissipations within [10-6,10-4] W.kg-1 caused at 65 % apart from internal tides in their generation zone, and [10-8,10-7] W.kg-1 caused at 50.4 % by mean circulation of surrounding water masses far fields. Finally, estimates of nutrient fluxes showed a very high flux of nitrate ([10-2, 10-0] mmol N m-2.s-1) and phosphate ([10-3, 10-1] mmol P m-2.s-1), due to both processes in Amazon region.
Stefania A. Ciliberti, Enrique Alvarez Fanjul, Jay Pearlman, Kirsten Wilmer-Becker, Pierre Bahurel, Fabrice Ardhuin, Alain Arnaud, Mike Bell, Segolene Berthou, Laurent Bertino, Arthur Capet, Eric Chassignet, Stefano Ciavatta, Mauro Cirano, Emanuela Clementi, Gianpiero Cossarini, Gianpaolo Coro, Stuart Corney, Fraser Davidson, Marie Drevillon, Yann Drillet, Renaud Dussurget, Ghada El Serafy, Katja Fennel, Marcos Garcia Sotillo, Patrick Heimbach, Fabrice Hernandez, Patrick Hogan, Ibrahim Hoteit, Sudheer Joseph, Simon Josey, Pierre-Yves Le Traon, Simone Libralato, Marco Mancini, Pascal Matte, Angelique Melet, Yasumasa Miyazawa, Andrew M. Moore, Antonio Novellino, Andrew Porter, Heather Regan, Laia Romero, Andreas Schiller, John Siddorn, Joanna Staneva, Cecile Thomas-Courcoux, Marina Tonani, Jose Maria Garcia-Valdecasas, Jennifer Veitch, Karina von Schuckmann, Liying Wan, John Wilkin, and Romane Zufic
State Planet, 1-osr7, 2, https://doi.org/10.5194/sp-1-osr7-2-2023, https://doi.org/10.5194/sp-1-osr7-2-2023, 2023
Alice Carret, Florence Birol, Claude Estournel, and Bruno Zakardjian
Ocean Sci., 19, 903–921, https://doi.org/10.5194/os-19-903-2023, https://doi.org/10.5194/os-19-903-2023, 2023
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This study presents a methodology to investigate the ability of satellite altimetry to observe a coastal current, the Northern Current, in the NW Mediterannean Sea. We use a high-resolution regional model, validated with HF radars and in situ data. The model is used as a reference and compared to three different missions (Jason 2, SARAL and Sentinel-3), studying both the surface velocity and the sea surface height signature of the current. The performance of the three missions was also compared.
Josefine Herrford, Peter Brandt, Torsten Kanzow, Rebecca Hummels, Moacyr Araujo, and Jonathan V. Durgadoo
Ocean Sci., 17, 265–284, https://doi.org/10.5194/os-17-265-2021, https://doi.org/10.5194/os-17-265-2021, 2021
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The Atlantic Meridional Overturning Circulation (AMOC) is an important component of the climate system. Understanding its structure and variability is a key priority for many scientists. Here, we present the first estimate of AMOC variations for the tropical South Atlantic from the TRACOS array at 11° S. Over the observed period, the AMOC was dominated by seasonal variability. We investigate the respective mechanisms with an ocean model and find that different wind-forced waves play a big role.
Yvan Gouzenes, Fabien Léger, Anny Cazenave, Florence Birol, Pascal Bonnefond, Marcello Passaro, Fernando Nino, Rafael Almar, Olivier Laurain, Christian Schwatke, Jean-François Legeais, and Jérôme Benveniste
Ocean Sci., 16, 1165–1182, https://doi.org/10.5194/os-16-1165-2020, https://doi.org/10.5194/os-16-1165-2020, 2020
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This study provides for the first time estimates of sea level anomalies very close to the coastline based on high-resolution retracked altimetry data, as well as corresponding sea level trends, over a 14-year time span. This new information has so far not been provided by standard altimetry data.
Alice Carret, Florence Birol, Claude Estournel, Bruno Zakardjian, and Pierre Testor
Ocean Sci., 15, 269–290, https://doi.org/10.5194/os-15-269-2019, https://doi.org/10.5194/os-15-269-2019, 2019
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This study uses different in situ and satellite measurements to investigate ocean circulation in the NW Mediterranean Sea. We analyze how the different instruments (satellite altimetry, HF radars, gliders, ADCPs) capture current variability and how they complement each other. We demonstrate the ability of satellite altimetry to capture the fluctuations of the narrow coastal Northern Current at different timescales. This study provides an integrated approach to a coastal dynamics study.
Ivan Manso-Narvarte, Ainhoa Caballero, Anna Rubio, Claire Dufau, and Florence Birol
Ocean Sci., 14, 1265–1281, https://doi.org/10.5194/os-14-1265-2018, https://doi.org/10.5194/os-14-1265-2018, 2018
Short summary
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Our main aim is to compare two different measuring systems of the surface ocean currents: land-based, high-frequency radar and satellite altimetry. Results show that the surface currents detected by both systems agree up to a 70 %, mostly in areas of persistent currents. This work is a first step in the combination of both technologies for an improved monitoring of the coastal surface ocean dynamics.
Sandrine Djakouré, Moacyr Araujo, Aubains Hounsou-Gbo, Carlos Noriega, and Bernard Bourlès
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-346, https://doi.org/10.5194/bg-2017-346, 2017
Revised manuscript has not been submitted
Eghbert Elvan Ampou, Ofri Johan, Christophe E. Menkes, Fernando Niño, Florence Birol, Sylvain Ouillon, and Serge Andréfouët
Biogeosciences, 14, 817–826, https://doi.org/10.5194/bg-14-817-2017, https://doi.org/10.5194/bg-14-817-2017, 2017
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The 2015–2016 El Niño was the strongest on record and has generated significant coral bleaching and mortality worldwide. In Indonesia, first signs of bleaching were reported in April 2016. However, we show that this El Niño has impacted Indonesian reefs since 2015 through a different process than temperature-induced bleaching. Another El Niño-induced process, sea level fall, is responsible for significant coral mortality on North Sulawesi shallow reefs, and probably throughout Indonesia.
Rosemary Morrow, Alice Carret, Florence Birol, Fernando Nino, Guillaume Valladeau, Francois Boy, Celine Bachelier, and Bruno Zakardjian
Ocean Sci., 13, 13–29, https://doi.org/10.5194/os-13-13-2017, https://doi.org/10.5194/os-13-13-2017, 2017
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Spectral analyses of along-track altimetric data are used to estimate noise levels and observable ocean scales in the NW Mediterranean Sea. In winter, all altimetric missions can observe wavelengths down to 40–50 km (individual feature diameters of 20–25 km). In summer, SARAL can detect scales down to 35 km, whereas Jason-2 and CryoSat-2 with higher noise can only observe scales less than 50–55 km. Along-track altimeter data are also compared with collocated glider and coastal HF radar data.
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Short summary
Altimeter-derived currents are used here to revisit the seasonal and interannual variability of all surface currents involved in the western tropical Atlantic circulation. A new approach based on the calculation of the current strengths and core positions is used to investigate the relationship between the currents, the remote wind variability, and the tropical Atlantic modes. The results show relationships at the seasonal and interannual timescale depending on the location of the currents.
Altimeter-derived currents are used here to revisit the seasonal and interannual variability of...