Articles | Volume 22, issue 14
https://doi.org/10.5194/bg-22-3485-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-3485-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
18 Jul 2025
Research article | Highlight paper |
| 18 Jul 2025
| 18 Jul 2025
Marine snow morphology drives sinking and attenuation in the ocean interior
Yawouvi Dodji Soviadan
CORRESPONDING AUTHOR
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
Université de Lomé, Lomé, TOGO, France
MARBEC, IRD, IFREMER, CNRS, Université de Montpellier, 87 Avenue Jean Monnet, 34200 Sète, France
Miriam Beck
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
FRB-CESAB, Montpellier, France
Joelle Habib
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
Alberto Baudena
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
Consiglio Nazionale Delle Ricerche-Istituto di Scienze Marine (CNR-ISMAR), Lerici (SP), Italy
Laetitia Drago
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
Sorbonne Université, UMR 7159 CNRS-IRD-MNHN, LOCEAN-IPSL, Paris, France
Alexandre Accardo
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
Remi Laxenaire
Laboratoire de l'Atmosphère et des Cyclones, LACy, UMR 8105, CNRS, Université de La Réunion, Météo-France, Saint-Denis de La Réunion, France
Center for Ocean-Atmospheric Prediction Studies, Florida State University, Tallahassee, FL, USA
Sabrina Speich
Laboratoire de Météorologie Dynamique – IPSL, ENS – PSL, Paris, France
Peter Brandt
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Faculty of Mathematics and Natural Sciences, Kiel University, Kiel, Germany
Rainer Kiko
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Faculty of Mathematics and Natural Sciences, Kiel University, Kiel, Germany
Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, UMR 7093 LOV, Villefranche-sur-Mer, France
Institut Universitaire de France, Paris, France
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Yan Barabinot, Sabrina Speich, and Xavier Carton
Ocean Sci., 21, 2527–2553, https://doi.org/10.5194/os-21-2527-2025, https://doi.org/10.5194/os-21-2527-2025, 2025
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Joelle Habib, Caroline Ulses, Claude Estournel, Milad Fakhri, Patrick Marsaleix, Thierry Moutin, Dominique Lefevre, Mireille Pujo-Pay, Marine Fourrier, Laurent Coppola, Cathy Wimart-Rousseau, and Pascal Conan
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Yan Barabinot, Sabrina Speich, Xavier Carton, Pierre L'Hégaret, Corentin Subirade, Rémi Laxenaire, and Johannes Karstensen
Ocean Sci., 21, 1849–1872, https://doi.org/10.5194/os-21-1849-2025, https://doi.org/10.5194/os-21-1849-2025, 2025
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Mesoscale eddies are rotating oceanic currents key to ocean variability. Off Brazil’s northeast coast, the North Brazil Current generates on average 4.5 eddies per year, which drift towards the West Indies, transporting waters from the Southern Hemisphere. Using data collected at sea by the EUREC4A-OA cruise, this study reveals that deep eddies transport 5 times more water than surface ones, reshaping our understanding of the regional water transport.
Ariadna Celina Nocera, Lars Stemmann, Marcel Babin, Tristan Biard, Julie Coustenoble, François Carlotti, Laurent Coppola, Lucas Courchet, Laetitia Drago, Amanda Elineau, Lionel Guidi, Helena Hauss, Laëtitia Jalabert, Lee Karp-Boss, Rainer Kiko, Manon Laget, Fabien Lombard, Andrew McDonnell, Camille Merland, Solène Motreuil, Thelma Panaïotis, Marc Picheral, Andreas Rogge, Anya Waite, and Jean-Olivier Irisson
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-522, https://doi.org/10.5194/essd-2025-522, 2025
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Plankton and detritus play a key role in ocean health and climate regulation. We present a large global dataset of images and information collected from 2008 to 2018 using specialized underwater camera (UVP). This publicly available dataset will support more accurate ecological models and help train artificial intelligence tools, improving how scientists track ocean biodiversity and monitor environmental changes.
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EGUsphere, https://doi.org/10.5194/egusphere-2025-3746, https://doi.org/10.5194/egusphere-2025-3746, 2025
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Florian Schütte, Johannes Hahn, Ivy Frenger, Arne Bendinger, Fehmi Dilmahamod, Marco Schulz, and Peter Brandt
EGUsphere, https://doi.org/10.5194/egusphere-2025-2175, https://doi.org/10.5194/egusphere-2025-2175, 2025
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We found extreme drops in oxygen levels in the tropical Atlantic linked to surprisingly long-lived, small subsurface eddies. These eddies are hidden beneath the surface (undetectable by satellites) and are unusually stable, even in the highly dynamic ocean near the equator. Using long-term measurements and computer models, we show that these features can strongly influence oxygen supply and potentially impact marine ecosystems.
Léo C. Aroucha, Joke F. Lübbecke, Peter Brandt, Franziska U. Schwarzkopf, and Arne Biastoch
Ocean Sci., 21, 661–678, https://doi.org/10.5194/os-21-661-2025, https://doi.org/10.5194/os-21-661-2025, 2025
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The west African coastal region sustains highly productive fisheries and marine ecosystems influenced by sea surface temperature. We use oceanic models to show that the freshwater input from land to ocean strengthens a surface northward (southward) coastal current north (south) of the Congo River mouth, promoting a transfer of cooler (warmer) waters to north (south) of the Congo discharge location. We highlight the significant impact of river discharge on ocean temperatures and circulation.
Alexandre Accardo, Rémi Laxenaire, Alberto Baudena, Sabrina Speich, Rainer Kiko, and Lars Stemmann
Biogeosciences, 22, 1183–1201, https://doi.org/10.5194/bg-22-1183-2025, https://doi.org/10.5194/bg-22-1183-2025, 2025
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Nasrollah Moradi, Lili Hufnagel, Simon Ramondenc, Clara Flintrop, Rainer Kiko, Tim Fischer, Helena Hauss, Arne Körtzinger, Gerhard Fischer, and Morten Iversen
EGUsphere, https://doi.org/10.5194/egusphere-2025-347, https://doi.org/10.5194/egusphere-2025-347, 2025
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Yan Barabinot, Sabrina Speich, and Xavier Carton
Ocean Sci., 21, 151–179, https://doi.org/10.5194/os-21-151-2025, https://doi.org/10.5194/os-21-151-2025, 2025
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Joelle Habib, Lars Stemmann, Alexandre Accardo, Alberto Baudena, Franz Philip Tuchen, Peter Brandt, and Rainer Kiko
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Kristin Burmeister, Franziska U. Schwarzkopf, Willi Rath, Arne Biastoch, Peter Brandt, Joke F. Lübbecke, and Mark Inall
Ocean Sci., 20, 307–339, https://doi.org/10.5194/os-20-307-2024, https://doi.org/10.5194/os-20-307-2024, 2024
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We apply two different forcing products to a high-resolution ocean model to investigate their impact on the simulated upper-current field in the tropical Atlantic. Where possible, we compare the simulated results to long-term observations. We find large discrepancies between the two simulations regarding the wind and current fields. We propose that long-term observations, once they have reached a critical length, need to be used to test the quality of wind-driven simulations.
Jonathan Andrew Baker, Richard Renshaw, Laura Claire Jackson, Clotilde Dubois, Doroteaciro Iovino, Hao Zuo, Renellys C. Perez, Shenfu Dong, Marion Kersalé, Michael Mayer, Johannes Mayer, Sabrina Speich, and Tarron Lamont
State Planet, 1-osr7, 4, https://doi.org/10.5194/sp-1-osr7-4-2023, https://doi.org/10.5194/sp-1-osr7-4-2023, 2023
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We use ocean reanalyses, in which ocean models are combined with observations, to infer past changes in ocean circulation and heat transport in the South Atlantic. Comparing these estimates with other observation-based estimates, we find differences in their trends, variability, and mean heat transport but closer agreement in their mean overturning strength. Ocean reanalyses can help us understand the cause of these differences, which could improve estimates of ocean transports in this region.
Joelle Habib, Caroline Ulses, Claude Estournel, Milad Fakhri, Patrick Marsaleix, Mireille Pujo-Pay, Marine Fourrier, Laurent Coppola, Alexandre Mignot, Laurent Mortier, and Pascal Conan
Biogeosciences, 20, 3203–3228, https://doi.org/10.5194/bg-20-3203-2023, https://doi.org/10.5194/bg-20-3203-2023, 2023
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The Rhodes Gyre, eastern Mediterranean Sea, is the main Levantine Intermediate Water formation site. In this study, we use a 3D physical–biogeochemical model to investigate the seasonal and interannual variability of organic carbon dynamics in the gyre. Our results show its autotrophic nature and its high interannual variability, with enhanced primary production, downward exports, and onward exports to the surrounding regions during years marked by intense heat losses and deep mixed layers.
Saeed Hariri, Sabrina Speich, Bruno Blanke, and Marina Lévy
Ocean Sci., 19, 1183–1201, https://doi.org/10.5194/os-19-1183-2023, https://doi.org/10.5194/os-19-1183-2023, 2023
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This work presents a series of studies conducted by the authors on the application of the Lagrangian approach for the connectivity analysis between different ocean locations in an idealized open-ocean model. We assess how the connectivity properties of typical oceanic flows are affected by the fine-scale circulation and discuss the challenges facing ocean connectivity estimates related to the spatial resolution. Our results are important to improve the understanding of marine ecosystems.
Swantje Bastin, Martin Claus, Richard J. Greatbatch, and Peter Brandt
Ocean Sci., 19, 923–939, https://doi.org/10.5194/os-19-923-2023, https://doi.org/10.5194/os-19-923-2023, 2023
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Equatorial deep jets are ocean currents that flow along the Equator in the deep oceans. They are relevant for oxygen transport and tropical surface climate, but their dynamics are not yet entirely understood. We investigate different factors leading to the jets being broader than theory predicts. Mainly using an ocean model, but corroborating the results with shipboard observations, we show that loss of momentum is the main factor for the broadening but that meandering also contributes.
Peter Brandt, Gaël Alory, Founi Mesmin Awo, Marcus Dengler, Sandrine Djakouré, Rodrigue Anicet Imbol Koungue, Julien Jouanno, Mareike Körner, Marisa Roch, and Mathieu Rouault
Ocean Sci., 19, 581–601, https://doi.org/10.5194/os-19-581-2023, https://doi.org/10.5194/os-19-581-2023, 2023
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Tropical upwelling systems are among the most productive ecosystems globally. The tropical Atlantic upwelling undergoes a strong seasonal cycle that is forced by the wind. Local wind-driven upwelling and remote effects, particularly via the propagation of equatorial and coastal trapped waves, lead to an upward and downward movement of the nitracline. Turbulent mixing results in upward supply of nutrients. Here, we review the different physical processes responsible for biological productivity.
Pierre L'Hégaret, Florian Schütte, Sabrina Speich, Gilles Reverdin, Dariusz B. Baranowski, Rena Czeschel, Tim Fischer, Gregory R. Foltz, Karen J. Heywood, Gerd Krahmann, Rémi Laxenaire, Caroline Le Bihan, Philippe Le Bot, Stéphane Leizour, Callum Rollo, Michael Schlundt, Elizabeth Siddle, Corentin Subirade, Dongxiao Zhang, and Johannes Karstensen
Earth Syst. Sci. Data, 15, 1801–1830, https://doi.org/10.5194/essd-15-1801-2023, https://doi.org/10.5194/essd-15-1801-2023, 2023
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In early 2020, the EUREC4A-OA/ATOMIC experiment took place in the northwestern Tropical Atlantic Ocean, a dynamical region where different water masses interact. Four oceanographic vessels and a fleet of autonomous devices were deployed to study the processes at play and sample the upper ocean, each with its own observing capability. The article first describes the data calibration and validation and second their cross-validation, using a hierarchy of instruments and estimating the uncertainty.
Patricia Ayón Dejo, Elda Luz Pinedo Arteaga, Anna Schukat, Jan Taucher, Rainer Kiko, Helena Hauss, Sabrina Dorschner, Wilhelm Hagen, Mariona Segura-Noguera, and Silke Lischka
Biogeosciences, 20, 945–969, https://doi.org/10.5194/bg-20-945-2023, https://doi.org/10.5194/bg-20-945-2023, 2023
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Ocean upwelling regions are highly productive. With ocean warming, severe changes in upwelling frequency and/or intensity and expansion of accompanying oxygen minimum zones are projected. In a field experiment off Peru, we investigated how different upwelling intensities affect the pelagic food web and found failed reproduction of dominant zooplankton. The changes projected could severely impact the reproductive success of zooplankton communities and the pelagic food web in upwelling regions.
Adriana Bailey, Franziska Aemisegger, Leonie Villiger, Sebastian A. Los, Gilles Reverdin, Estefanía Quiñones Meléndez, Claudia Acquistapace, Dariusz B. Baranowski, Tobias Böck, Sandrine Bony, Tobias Bordsdorff, Derek Coffman, Simon P. de Szoeke, Christopher J. Diekmann, Marina Dütsch, Benjamin Ertl, Joseph Galewsky, Dean Henze, Przemyslaw Makuch, David Noone, Patricia K. Quinn, Michael Rösch, Andreas Schneider, Matthias Schneider, Sabrina Speich, Bjorn Stevens, and Elizabeth J. Thompson
Earth Syst. Sci. Data, 15, 465–495, https://doi.org/10.5194/essd-15-465-2023, https://doi.org/10.5194/essd-15-465-2023, 2023
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One of the novel ways EUREC4A set out to investigate trade wind clouds and their coupling to the large-scale circulation was through an extensive network of isotopic measurements in water vapor, precipitation, and seawater. Samples were taken from the island of Barbados, from aboard two aircraft, and from aboard four ships. This paper describes the full collection of EUREC4A isotopic in situ data and guides readers to complementary remotely sensed water vapor isotope ratios.
Mareike Körner, Peter Brandt, and Marcus Dengler
Ocean Sci., 19, 121–139, https://doi.org/10.5194/os-19-121-2023, https://doi.org/10.5194/os-19-121-2023, 2023
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The coastal waters off Angola host a productive ecosystem. Surface waters at the coast are colder than further offshore. We find that surface heat fluxes warm the coastal region more strongly than the offshore region and cannot explain the differences. The influence of horizontal heat advection is minor on the surface temperature change. In contrast, ocean turbulence data suggest that cooling associated with vertical mixing is an important mechanism to explain the near-coastal cooling.
Rainer Kiko, Marc Picheral, David Antoine, Marcel Babin, Léo Berline, Tristan Biard, Emmanuel Boss, Peter Brandt, Francois Carlotti, Svenja Christiansen, Laurent Coppola, Leandro de la Cruz, Emilie Diamond-Riquier, Xavier Durrieu de Madron, Amanda Elineau, Gabriel Gorsky, Lionel Guidi, Helena Hauss, Jean-Olivier Irisson, Lee Karp-Boss, Johannes Karstensen, Dong-gyun Kim, Rachel M. Lekanoff, Fabien Lombard, Rubens M. Lopes, Claudie Marec, Andrew M. P. McDonnell, Daniela Niemeyer, Margaux Noyon, Stephanie H. O'Daly, Mark D. Ohman, Jessica L. Pretty, Andreas Rogge, Sarah Searson, Masashi Shibata, Yuji Tanaka, Toste Tanhua, Jan Taucher, Emilia Trudnowska, Jessica S. Turner, Anya Waite, and Lars Stemmann
Earth Syst. Sci. Data, 14, 4315–4337, https://doi.org/10.5194/essd-14-4315-2022, https://doi.org/10.5194/essd-14-4315-2022, 2022
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The term
marine particlescomprises detrital aggregates; fecal pellets; bacterioplankton, phytoplankton and zooplankton; and even fish. Here, we present a global dataset that contains 8805 vertical particle size distribution profiles obtained with Underwater Vision Profiler 5 (UVP5) camera systems. These data are valuable to the scientific community, as they can be used to constrain important biogeochemical processes in the ocean, such as the flux of carbon to the deep sea.
Léa Olivier, Jacqueline Boutin, Gilles Reverdin, Nathalie Lefèvre, Peter Landschützer, Sabrina Speich, Johannes Karstensen, Matthieu Labaste, Christophe Noisel, Markus Ritschel, Tobias Steinhoff, and Rik Wanninkhof
Biogeosciences, 19, 2969–2988, https://doi.org/10.5194/bg-19-2969-2022, https://doi.org/10.5194/bg-19-2969-2022, 2022
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We investigate the impact of the interactions between eddies and the Amazon River plume on the CO2 air–sea fluxes to better characterize the ocean carbon sink in winter 2020. The region is a strong CO2 sink, previously underestimated by a factor of 10 due to a lack of data and understanding of the processes responsible for the variability in ocean carbon parameters. The CO2 absorption is mainly driven by freshwater from the Amazon entrained by eddies and by the winter seasonal cooling.
Natalia Belkin, Tamar Guy-Haim, Maxim Rubin-Blum, Ayah Lazar, Guy Sisma-Ventura, Rainer Kiko, Arseniy R. Morov, Tal Ozer, Isaac Gertman, Barak Herut, and Eyal Rahav
Ocean Sci., 18, 693–715, https://doi.org/10.5194/os-18-693-2022, https://doi.org/10.5194/os-18-693-2022, 2022
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We studied how distinct water circulations that elevate (cyclone) or descend (anticyclone) water from the upper ocean affect the biomass, activity and diversity of planktonic microorganisms in the impoverished eastern Mediterranean. We show that cyclonic and anticyclonic eddies differ in their community composition and production. Moreover, the anticyclone may be a potential bio-invasion and dispersal vector, while the cyclone may serve as a thermal refugee for native species.
Bjorn Stevens, Sandrine Bony, David Farrell, Felix Ament, Alan Blyth, Christopher Fairall, Johannes Karstensen, Patricia K. Quinn, Sabrina Speich, Claudia Acquistapace, Franziska Aemisegger, Anna Lea Albright, Hugo Bellenger, Eberhard Bodenschatz, Kathy-Ann Caesar, Rebecca Chewitt-Lucas, Gijs de Boer, Julien Delanoë, Leif Denby, Florian Ewald, Benjamin Fildier, Marvin Forde, Geet George, Silke Gross, Martin Hagen, Andrea Hausold, Karen J. Heywood, Lutz Hirsch, Marek Jacob, Friedhelm Jansen, Stefan Kinne, Daniel Klocke, Tobias Kölling, Heike Konow, Marie Lothon, Wiebke Mohr, Ann Kristin Naumann, Louise Nuijens, Léa Olivier, Robert Pincus, Mira Pöhlker, Gilles Reverdin, Gregory Roberts, Sabrina Schnitt, Hauke Schulz, A. Pier Siebesma, Claudia Christine Stephan, Peter Sullivan, Ludovic Touzé-Peiffer, Jessica Vial, Raphaela Vogel, Paquita Zuidema, Nicola Alexander, Lyndon Alves, Sophian Arixi, Hamish Asmath, Gholamhossein Bagheri, Katharina Baier, Adriana Bailey, Dariusz Baranowski, Alexandre Baron, Sébastien Barrau, Paul A. Barrett, Frédéric Batier, Andreas Behrendt, Arne Bendinger, Florent Beucher, Sebastien Bigorre, Edmund Blades, Peter Blossey, Olivier Bock, Steven Böing, Pierre Bosser, Denis Bourras, Pascale Bouruet-Aubertot, Keith Bower, Pierre Branellec, Hubert Branger, Michal Brennek, Alan Brewer, Pierre-Etienne Brilouet, Björn Brügmann, Stefan A. Buehler, Elmo Burke, Ralph Burton, Radiance Calmer, Jean-Christophe Canonici, Xavier Carton, Gregory Cato Jr., Jude Andre Charles, Patrick Chazette, Yanxu Chen, Michal T. Chilinski, Thomas Choularton, Patrick Chuang, Shamal Clarke, Hugh Coe, Céline Cornet, Pierre Coutris, Fleur Couvreux, Susanne Crewell, Timothy Cronin, Zhiqiang Cui, Yannis Cuypers, Alton Daley, Gillian M. Damerell, Thibaut Dauhut, Hartwig Deneke, Jean-Philippe Desbios, Steffen Dörner, Sebastian Donner, Vincent Douet, Kyla Drushka, Marina Dütsch, André Ehrlich, Kerry Emanuel, Alexandros Emmanouilidis, Jean-Claude Etienne, Sheryl Etienne-Leblanc, Ghislain Faure, Graham Feingold, Luca Ferrero, Andreas Fix, Cyrille Flamant, Piotr Jacek Flatau, Gregory R. Foltz, Linda Forster, Iulian Furtuna, Alan Gadian, Joseph Galewsky, Martin Gallagher, Peter Gallimore, Cassandra Gaston, Chelle Gentemann, Nicolas Geyskens, Andreas Giez, John Gollop, Isabelle Gouirand, Christophe Gourbeyre, Dörte de Graaf, Geiske E. de Groot, Robert Grosz, Johannes Güttler, Manuel Gutleben, Kashawn Hall, George Harris, Kevin C. Helfer, Dean Henze, Calvert Herbert, Bruna Holanda, Antonio Ibanez-Landeta, Janet Intrieri, Suneil Iyer, Fabrice Julien, Heike Kalesse, Jan Kazil, Alexander Kellman, Abiel T. Kidane, Ulrike Kirchner, Marcus Klingebiel, Mareike Körner, Leslie Ann Kremper, Jan Kretzschmar, Ovid Krüger, Wojciech Kumala, Armin Kurz, Pierre L'Hégaret, Matthieu Labaste, Tom Lachlan-Cope, Arlene Laing, Peter Landschützer, Theresa Lang, Diego Lange, Ingo Lange, Clément Laplace, Gauke Lavik, Rémi Laxenaire, Caroline Le Bihan, Mason Leandro, Nathalie Lefevre, Marius Lena, Donald Lenschow, Qiang Li, Gary Lloyd, Sebastian Los, Niccolò Losi, Oscar Lovell, Christopher Luneau, Przemyslaw Makuch, Szymon Malinowski, Gaston Manta, Eleni Marinou, Nicholas Marsden, Sebastien Masson, Nicolas Maury, Bernhard Mayer, Margarette Mayers-Als, Christophe Mazel, Wayne McGeary, James C. McWilliams, Mario Mech, Melina Mehlmann, Agostino Niyonkuru Meroni, Theresa Mieslinger, Andreas Minikin, Peter Minnett, Gregor Möller, Yanmichel Morfa Avalos, Caroline Muller, Ionela Musat, Anna Napoli, Almuth Neuberger, Christophe Noisel, David Noone, Freja Nordsiek, Jakub L. Nowak, Lothar Oswald, Douglas J. Parker, Carolyn Peck, Renaud Person, Miriam Philippi, Albert Plueddemann, Christopher Pöhlker, Veronika Pörtge, Ulrich Pöschl, Lawrence Pologne, Michał Posyniak, Marc Prange, Estefanía Quiñones Meléndez, Jule Radtke, Karim Ramage, Jens Reimann, Lionel Renault, Klaus Reus, Ashford Reyes, Joachim Ribbe, Maximilian Ringel, Markus Ritschel, Cesar B. Rocha, Nicolas Rochetin, Johannes Röttenbacher, Callum Rollo, Haley Royer, Pauline Sadoulet, Leo Saffin, Sanola Sandiford, Irina Sandu, Michael Schäfer, Vera Schemann, Imke Schirmacher, Oliver Schlenczek, Jerome Schmidt, Marcel Schröder, Alfons Schwarzenboeck, Andrea Sealy, Christoph J. Senff, Ilya Serikov, Samkeyat Shohan, Elizabeth Siddle, Alexander Smirnov, Florian Späth, Branden Spooner, M. Katharina Stolla, Wojciech Szkółka, Simon P. de Szoeke, Stéphane Tarot, Eleni Tetoni, Elizabeth Thompson, Jim Thomson, Lorenzo Tomassini, Julien Totems, Alma Anna Ubele, Leonie Villiger, Jan von Arx, Thomas Wagner, Andi Walther, Ben Webber, Manfred Wendisch, Shanice Whitehall, Anton Wiltshire, Allison A. Wing, Martin Wirth, Jonathan Wiskandt, Kevin Wolf, Ludwig Worbes, Ethan Wright, Volker Wulfmeyer, Shanea Young, Chidong Zhang, Dongxiao Zhang, Florian Ziemen, Tobias Zinner, and Martin Zöger
Earth Syst. Sci. Data, 13, 4067–4119, https://doi.org/10.5194/essd-13-4067-2021, https://doi.org/10.5194/essd-13-4067-2021, 2021
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The EUREC4A field campaign, designed to test hypothesized mechanisms by which clouds respond to warming and benchmark next-generation Earth-system models, is presented. EUREC4A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. It was the first campaign that attempted to characterize the full range of processes and scales influencing trade wind clouds.
Mariana Hill Cruz, Iris Kriest, Yonss Saranga José, Rainer Kiko, Helena Hauss, and Andreas Oschlies
Biogeosciences, 18, 2891–2916, https://doi.org/10.5194/bg-18-2891-2021, https://doi.org/10.5194/bg-18-2891-2021, 2021
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In this study we use a regional biogeochemical model of the eastern tropical South Pacific Ocean to implicitly simulate the effect that fluctuations in populations of small pelagic fish, such as anchovy and sardine, may have on the biogeochemistry of the northern Humboldt Current System. To do so, we vary the zooplankton mortality in the model, under the assumption that these fishes eat zooplankton. We also evaluate the model for the first time against mesozooplankton observations.
Gerd Krahmann, Damian L. Arévalo-Martínez, Andrew W. Dale, Marcus Dengler, Anja Engel, Nicolaas Glock, Patricia Grasse, Johannes Hahn, Helena Hauss, Mark Hopwood, Rainer Kiko, Alexandra Loginova, Carolin R. Löscher, Marie Maßmig, Alexandra-Sophie Roy, Renato Salvatteci, Stefan Sommer, Toste Tanhua, and Hela Mehrtens
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2020-308, https://doi.org/10.5194/essd-2020-308, 2021
Preprint withdrawn
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The project "Climate-Biogeochemistry Interactions in the Tropical Ocean" (SFB 754) was a multidisciplinary research project active from 2008 to 2019 aimed at a better understanding of the coupling between the tropical climate and ocean circulation and the ocean's oxygen and nutrient balance. On 34 research cruises, mainly in the Southeast Tropical Pacific and the Northeast Tropical Atlantic, 1071 physical, chemical and biological data sets were collected.
Pierre Bosser, Olivier Bock, Cyrille Flamant, Sandrine Bony, and Sabrina Speich
Earth Syst. Sci. Data, 13, 1499–1517, https://doi.org/10.5194/essd-13-1499-2021, https://doi.org/10.5194/essd-13-1499-2021, 2021
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In the framework of the EUREC4A campaign, water vapour measurements were retrieved over the tropical west Atlantic Ocean from GNSS data acquired from three research vessels (R/Vs Atalante, Maria S. Merian and Meteor). The retrievals from R/Vs Atalante and Meteor are shown to be of high quality unlike the results for the R/V Maria S. Merian. These ship-borne retrievals are intended to be used for the description and understanding of meteorological phenomena that occurred during the campaign.
Claudia Christine Stephan, Sabrina Schnitt, Hauke Schulz, Hugo Bellenger, Simon P. de Szoeke, Claudia Acquistapace, Katharina Baier, Thibaut Dauhut, Rémi Laxenaire, Yanmichel Morfa-Avalos, Renaud Person, Estefanía Quiñones Meléndez, Gholamhossein Bagheri, Tobias Böck, Alton Daley, Johannes Güttler, Kevin C. Helfer, Sebastian A. Los, Almuth Neuberger, Johannes Röttenbacher, Andreas Raeke, Maximilian Ringel, Markus Ritschel, Pauline Sadoulet, Imke Schirmacher, M. Katharina Stolla, Ethan Wright, Benjamin Charpentier, Alexis Doerenbecher, Richard Wilson, Friedhelm Jansen, Stefan Kinne, Gilles Reverdin, Sabrina Speich, Sandrine Bony, and Bjorn Stevens
Earth Syst. Sci. Data, 13, 491–514, https://doi.org/10.5194/essd-13-491-2021, https://doi.org/10.5194/essd-13-491-2021, 2021
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The EUREC4A field campaign took place in the western tropical Atlantic during January and February 2020. A total of 811 radiosondes, launched regularly (usually 4-hourly) from Barbados, and 4 ships measured wind, temperature, and relative humidity. They sampled atmospheric variability associated with different ocean surface conditions, synoptic variability, and mesoscale convective organization. The methods of data collection and post-processing for the radiosonde data are described here.
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.
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Co-editor-in-chief
This study is the first to measure marine snow morphologies, sinking speeds, and midwater attenuation in export plumes using a BGC-Argo float equipped with optical and imaging sensors, offering new insights into the effects of morphology on particle sinking. The findings emphasize the need to move beyond size-based models by incorporating morphological properties to improve understanding of particle sinking and enhance flux estimates, with potential applications for monitoring natural and human-induced export events at high spatio-temporal resolution.
This study is the first to measure marine snow morphologies, sinking speeds, and midwater...
Short summary
Key parameters representing the gravity flux in global models are sinking speed and vertical attenuation of exported material. We calculate, for the first time, these parameters in situ in the ocean for six intermittent blooms followed by export events using high-resolution (3 d) time series of 0–1000 m depth profiles from imaging sensors mounted on an Argo float. We show that sinking speed depends not only on size but also on the morphology of the particles, with density being an important property.
Key parameters representing the gravity flux in global models are sinking speed and vertical...
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