Articles | Volume 21, issue 2
https://doi.org/10.5194/os-21-661-2025
© 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/os-21-661-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Mar 2025
Research article |
| 18 Mar 2025
| 18 Mar 2025
River discharge impacts coastal southeastern tropical Atlantic sea surface temperature and circulation: a model-based analysis
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Joke F. Lübbecke
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Peter Brandt
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Faculty of Mathematics and Natural Sciences, Kiel University, Kiel, Germany
Franziska U. Schwarzkopf
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Arne Biastoch
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Faculty of Mathematics and Natural Sciences, Kiel University, Kiel, Germany
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Yawouvi Dodji Soviadan, Miriam Beck, Joelle Habib, Alberto Baudena, Laetitia Drago, Alexandre Accardo, Remi Laxenaire, Sabrina Speich, Peter Brandt, Rainer Kiko, and Stemmann Lars
Biogeosciences, 22, 3485–3501, https://doi.org/10.5194/bg-22-3485-2025, https://doi.org/10.5194/bg-22-3485-2025, 2025
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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.
Yannick Wölker, Willi Rath, Matthias Renz, and Arne Biastoch
EGUsphere, https://doi.org/10.5194/egusphere-2025-2782, https://doi.org/10.5194/egusphere-2025-2782, 2025
This preprint is open for discussion and under review for Ocean Science (OS).
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The Atlantic Meridional Overturning Circulation (AMOC) is a large current system that helps regulate Earth's climate. Monitoring the AMOC relies on fixed instruments anchored to the seafloor. This study explores in a high-resolution model whether data from Argo floats, autonomous drifters collecting hydrographic profiles, can be used to monitor the AMOC cost-effectively with the help of Machine Learning. Results suggest that Argo floats can extend AMOC monitoring beyond current fixed arrays.
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.
Tobias Schulzki, Franziska U. Schwarzkopf, and Arne Biastoch
EGUsphere, https://doi.org/10.5194/egusphere-2025-571, https://doi.org/10.5194/egusphere-2025-571, 2025
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Exceptionally high ocean temperatures can cause long-lasting damage to marine ecosystems. Most existing knowledge about such temperature extremes is focused on near-surface waters, yet ecosystems also thrive at greater depths. In this study, we present a comprehensive analysis of temperature extremes across the entire Atlantic Ocean, from the surface to the seafloor. Our findings underscore the importance of the ocean circulation in driving extreme temperature events.
Hendrik Großelindemann, Frederic S. Castruccio, Gokhan Danabasoglu, and Arne Biastoch
Ocean Sci., 21, 93–112, https://doi.org/10.5194/os-21-93-2025, https://doi.org/10.5194/os-21-93-2025, 2025
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This study investigates the Agulhas Leakage and examines its role in the global ocean circulation. It utilises a high-resolution Earth system model and a preindustrial climate to look at the response of the Agulhas Leakage to the wind field and the Atlantic Meridional Overturning Circulation (AMOC) and its evolution under climate change. The Agulhas Leakage could influence the stability of the AMOC, whose possible collapse would impact the climate in the Northern Hemisphere.
Joelle Habib, Lars Stemmann, Alexandre Accardo, Alberto Baudena, Franz Philip Tuchen, Peter Brandt, and Rainer Kiko
EGUsphere, https://doi.org/10.5194/egusphere-2024-3365, https://doi.org/10.5194/egusphere-2024-3365, 2024
This preprint is open for discussion and under review for Biogeosciences (BG).
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This study investigates how carbon moves from the ocean surface to the depths in the equatorial Atlantic, contributing to long-term carbon storage. Using an Argo float equipped with a camera, we captured two periods with major carbon export events. By identifying particle types and their sinking behaviors, we found that smaller, compact particles are key drivers of carbon transport. Our findings underscore the value of using imaging tools on autonomous platforms in tracking carbon sequestration.
Eike E. Köhn, Richard J. Greatbatch, Peter Brandt, and Martin Claus
Ocean Sci., 20, 1281–1290, https://doi.org/10.5194/os-20-1281-2024, https://doi.org/10.5194/os-20-1281-2024, 2024
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The latitudinally alternating zonal jets are a ubiquitous feature of the ocean. We use a simple model to illustrate the potential role of these jets in the formation, maintenance, and multidecadal variability in the oxygen minimum zones, using the eastern tropical North Atlantic oxygen minimum zone as an example.
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.
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.
Jake W. Casselman, Joke F. Lübbecke, Tobias Bayr, Wenjuan Huo, Sebastian Wahl, and Daniela I. V. Domeisen
Weather Clim. Dynam., 4, 471–487, https://doi.org/10.5194/wcd-4-471-2023, https://doi.org/10.5194/wcd-4-471-2023, 2023
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El Niño–Southern Oscillation (ENSO) has remote effects on the tropical North Atlantic (TNA), but the connections' nonlinearity (strength of response to an increasing ENSO signal) is not always well represented in models. Using the Community Earth System Model version 1 – Whole Atmosphere Community Climate Mode (CESM-WACCM) and the Flexible Ocean and Climate Infrastructure version 1, we find that the TNA responds linearly to extreme El Niño but nonlinearly to extreme La Niña for CESM-WACCM.
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.
Torge Martin and Arne Biastoch
Ocean Sci., 19, 141–167, https://doi.org/10.5194/os-19-141-2023, https://doi.org/10.5194/os-19-141-2023, 2023
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How is the ocean affected by continued Greenland Ice Sheet mass loss? We show in a systematic set of model experiments that atmospheric feedback needs to be accounted for as the large-scale ocean circulation is more than twice as sensitive to the meltwater otherwise. Coastal winds, boundary currents, and ocean eddies play a key role in redistributing the meltwater. Eddy paramterization helps the coarse simulation to perform better in the Labrador Sea but not in the North Atlantic Current region.
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.
Alan D. Fox, Patricia Handmann, Christina Schmidt, Neil Fraser, Siren Rühs, Alejandra Sanchez-Franks, Torge Martin, Marilena Oltmanns, Clare Johnson, Willi Rath, N. Penny Holliday, Arne Biastoch, Stuart A. Cunningham, and Igor Yashayaev
Ocean Sci., 18, 1507–1533, https://doi.org/10.5194/os-18-1507-2022, https://doi.org/10.5194/os-18-1507-2022, 2022
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Observations of the eastern subpolar North Atlantic in the 2010s show exceptional freshening and cooling of the upper ocean, peaking in 2016 with the lowest salinities recorded for 120 years. Using results from a high-resolution ocean model, supported by observations, we propose that the leading cause is reduced surface cooling over the preceding decade in the Labrador Sea, leading to increased outflow of less dense water and so to freshening and cooling of the eastern subpolar North Atlantic.
Jörg Fröhle, Patricia V. K. Handmann, and Arne Biastoch
Ocean Sci., 18, 1431–1450, https://doi.org/10.5194/os-18-1431-2022, https://doi.org/10.5194/os-18-1431-2022, 2022
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Three deep-water masses pass the southern exit of the Labrador Sea. Usually they are defined by explicit density intervals linked to the formation region. We evaluate this relation in an ocean model by backtracking the paths the water follows for 40 years: 48 % densify without contact to the atmosphere, 24 % densify in contact with the atmosphere, and 19 % are from the Nordic Seas. All three contribute to a similar density range at 53° N with weak specific formation location characteristics.
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.
Takaya Uchida, Julien Le Sommer, Charles Stern, Ryan P. Abernathey, Chris Holdgraf, Aurélie Albert, Laurent Brodeau, Eric P. Chassignet, Xiaobiao Xu, Jonathan Gula, Guillaume Roullet, Nikolay Koldunov, Sergey Danilov, Qiang Wang, Dimitris Menemenlis, Clément Bricaud, Brian K. Arbic, Jay F. Shriver, Fangli Qiao, Bin Xiao, Arne Biastoch, René Schubert, Baylor Fox-Kemper, William K. Dewar, and Alan Wallcraft
Geosci. Model Dev., 15, 5829–5856, https://doi.org/10.5194/gmd-15-5829-2022, https://doi.org/10.5194/gmd-15-5829-2022, 2022
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Ocean and climate scientists have used numerical simulations as a tool to examine the ocean and climate system since the 1970s. Since then, owing to the continuous increase in computational power and advances in numerical methods, we have been able to simulate increasing complex phenomena. However, the fidelity of the simulations in representing the phenomena remains a core issue in the ocean science community. Here we propose a cloud-based framework to inter-compare and assess such simulations.
Jens Zinke, Takaaki K. Watanabe, Siren Rühs, Miriam Pfeiffer, Stefan Grab, Dieter Garbe-Schönberg, and Arne Biastoch
Clim. Past, 18, 1453–1474, https://doi.org/10.5194/cp-18-1453-2022, https://doi.org/10.5194/cp-18-1453-2022, 2022
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Salinity is an important and integrative measure of changes to the water cycle steered by changes to the balance between rainfall and evaporation and by vertical and horizontal movements of water parcels by ocean currents. However, salinity measurements in our oceans are extremely sparse. To fill this gap, we have developed a 334-year coral record of seawater oxygen isotopes that reflects salinity changes in the globally important Agulhas Current system and reveals its main oceanic drivers.
Ioana Ivanciu, Katja Matthes, Arne Biastoch, Sebastian Wahl, and Jan Harlaß
Weather Clim. Dynam., 3, 139–171, https://doi.org/10.5194/wcd-3-139-2022, https://doi.org/10.5194/wcd-3-139-2022, 2022
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Greenhouse gas concentrations continue to increase, while the Antarctic ozone hole is expected to recover during the twenty-first century. We separate the effects of ozone recovery and of greenhouse gases on the Southern Hemisphere atmospheric and oceanic circulation, and we find that ozone recovery is generally reducing the impact of greenhouse gases, with the exception of certain regions of the stratosphere during spring, where the two effects reinforce each other.
Arne Biastoch, Franziska U. Schwarzkopf, Klaus Getzlaff, Siren Rühs, Torge Martin, Markus Scheinert, Tobias Schulzki, Patricia Handmann, Rebecca Hummels, and Claus W. Böning
Ocean Sci., 17, 1177–1211, https://doi.org/10.5194/os-17-1177-2021, https://doi.org/10.5194/os-17-1177-2021, 2021
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The Atlantic Meridional Overturning Circulation (AMOC) quantifies the impact of the ocean on climate and climate change. Here we show that a high-resolution ocean model is able to realistically simulate ocean currents. While the mean representation of the AMOC depends on choices made for the model and on the atmospheric forcing, the temporal variability is quite robust. Comparing the ocean model with ocean observations, we able to identify that the AMOC has declined over the past two decades.
Christina Schmidt, Franziska U. Schwarzkopf, Siren Rühs, and Arne Biastoch
Ocean Sci., 17, 1067–1080, https://doi.org/10.5194/os-17-1067-2021, https://doi.org/10.5194/os-17-1067-2021, 2021
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We estimate Agulhas leakage, water flowing from the Indian Ocean to the South Atlantic, in an ocean model with two different tools. The mean transport, variability and trend of Agulhas leakage is simulated comparably with both tools, emphasising the robustness of our method. If the experiments are designed differently, the mean transport of Agulhas leakage is altered, but not the trend. Agulhas leakage waters cool and become less salty south of Africa resulting in a density increase.
Ioana Ivanciu, Katja Matthes, Sebastian Wahl, Jan Harlaß, and Arne Biastoch
Atmos. Chem. Phys., 21, 5777–5806, https://doi.org/10.5194/acp-21-5777-2021, https://doi.org/10.5194/acp-21-5777-2021, 2021
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The Antarctic ozone hole has driven substantial dynamical changes in the Southern Hemisphere atmosphere over the past decades. This study separates the historical impacts of ozone depletion from those of rising levels of greenhouse gases and investigates how these impacts are captured in two types of climate models: one using interactive atmospheric chemistry and one prescribing the CMIP6 ozone field. The effects of ozone depletion are more pronounced in the model with interactive chemistry.
Josefine Maas, Susann Tegtmeier, Yue Jia, Birgit Quack, Jonathan V. Durgadoo, and Arne Biastoch
Atmos. Chem. Phys., 21, 4103–4121, https://doi.org/10.5194/acp-21-4103-2021, https://doi.org/10.5194/acp-21-4103-2021, 2021
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Cooling-water disinfection at coastal power plants is a known source of atmospheric bromoform. A large source of anthropogenic bromoform is the industrial regions in East Asia. In current bottom-up flux estimates, these anthropogenic emissions are missing, underestimating the global air–sea flux of bromoform. With transport simulations, we show that by including anthropogenic bromoform from cooling-water treatment, the bottom-up flux estimates significantly improve in East and Southeast Asia.
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.
Katja Matthes, Arne Biastoch, Sebastian Wahl, Jan Harlaß, Torge Martin, Tim Brücher, Annika Drews, Dana Ehlert, Klaus Getzlaff, Fritz Krüger, Willi Rath, Markus Scheinert, Franziska U. Schwarzkopf, Tobias Bayr, Hauke Schmidt, and Wonsun Park
Geosci. Model Dev., 13, 2533–2568, https://doi.org/10.5194/gmd-13-2533-2020, https://doi.org/10.5194/gmd-13-2533-2020, 2020
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A new Earth system model, the Flexible Ocean and Climate Infrastructure (FOCI), is introduced, consisting of a high-top atmosphere, an ocean model, sea-ice and land surface model components. A unique feature of FOCI is the ability to explicitly resolve small-scale oceanic features, for example, the Agulhas Current and the Gulf Stream. It allows to study the evolution of the climate system on regional and seasonal to (multi)decadal scales and bridges the gap to coarse-resolution climate models.
Nele Tim, Eduardo Zorita, Kay-Christian Emeis, Franziska U. Schwarzkopf, Arne Biastoch, and Birgit Hünicke
Earth Syst. Dynam., 10, 847–858, https://doi.org/10.5194/esd-10-847-2019, https://doi.org/10.5194/esd-10-847-2019, 2019
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Our study reveals that the latitudinal position and intensity of Southern Hemisphere trades and westerlies are correlated. In the last decades the westerlies have shifted poleward and intensified. Furthermore, the latitudinal shifts and intensity of the trades and westerlies impact the sea surface temperatures around southern Africa and in the South Benguela upwelling region. The future development of wind stress depends on the strength of greenhouse gas forcing.
Franziska U. Schwarzkopf, Arne Biastoch, Claus W. Böning, Jérôme Chanut, Jonathan V. Durgadoo, Klaus Getzlaff, Jan Harlaß, Jan K. Rieck, Christina Roth, Markus M. Scheinert, and René Schubert
Geosci. Model Dev., 12, 3329–3355, https://doi.org/10.5194/gmd-12-3329-2019, https://doi.org/10.5194/gmd-12-3329-2019, 2019
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A family of nested global ocean general circulation model configurations, the INALT family, has been established with resolutions of 1/10°, 1/20° and 1/60° in the South Atlantic and western Indian oceans, covering the greater Agulhas Current (AC) system. The INALT family provides a consistent set of configurations that allows to address eddy dynamics in the AC system and their impact on the large-scale ocean circulation.
Josefine Maas, Susann Tegtmeier, Birgit Quack, Arne Biastoch, Jonathan V. Durgadoo, Siren Rühs, Stephan Gollasch, and Matej David
Ocean Sci., 15, 891–904, https://doi.org/10.5194/os-15-891-2019, https://doi.org/10.5194/os-15-891-2019, 2019
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In a large-scale analysis, the spread of disinfection by-products from oxidative ballast water treatment is investigated, with a focus on Southeast Asia where major ports are located. Halogenated compounds such as bromoform (CHBr3) are produced in the ballast water and, once emitted into the environment, can participate in ozone depletion. Anthropogenic bromoform is rapidly emitted into the atmosphere and can locally double around large ports. A large-scale impact cannot be found.
Tim Fischer, Annette Kock, Damian L. Arévalo-Martínez, Marcus Dengler, Peter Brandt, and Hermann W. Bange
Biogeosciences, 16, 2307–2328, https://doi.org/10.5194/bg-16-2307-2019, https://doi.org/10.5194/bg-16-2307-2019, 2019
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We investigated air–sea gas exchange in oceanic upwelling regions for the case of nitrous oxide off Peru. In this region, routine concentration measurements from ships at 5 m or 10 m depth prove to overestimate surface (bulk) concentration. Thus, standard estimates of gas exchange will show systematic error. This is due to very shallow stratified layers that inhibit exchange between surface water and waters below and can exist for several days. Maximum bias occurs in moderate wind conditions.
Siren Rühs, Franziska U. Schwarzkopf, Sabrina Speich, and Arne Biastoch
Ocean Sci., 15, 489–512, https://doi.org/10.5194/os-15-489-2019, https://doi.org/10.5194/os-15-489-2019, 2019
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We revisit the sources for the upper limb of the overturning circulation in the South Atlantic by tracking fluid particles in a high-resolution ocean model. Our results suggest that the upper limb’s transport is dominantly supplied by waters with Indian Ocean origin, but the contribution of waters with Pacific origin is substantially larger than previously estimated with coarse-resolution models. Yet, a large part of upper limb waters obtains thermohaline properties within the South Atlantic.
Yao Fu, Johannes Karstensen, and Peter Brandt
Ocean Sci., 14, 589–616, https://doi.org/10.5194/os-14-589-2018, https://doi.org/10.5194/os-14-589-2018, 2018
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Hydrographic analysis in the Atlantic along 14.5° N and 24.5° N shows that between the periods of 1989/92 and 2013/15, the Antarctic Intermediate Water became warmer and saltier at 14.5° N, and that the Antarctic Bottom Water became lighter at both latitudes. By applying a box inverse model, the Atlantic Meridional Overturning Circulation (AMOC) was determined. Comparison among the inverse solution, GECCO2, RAPID, and MOVE shows that the AMOC has not significantly changed in the past 20 years.
Fabrice Ardhuin, Yevgueny Aksenov, Alvise Benetazzo, Laurent Bertino, Peter Brandt, Eric Caubet, Bertrand Chapron, Fabrice Collard, Sophie Cravatte, Jean-Marc Delouis, Frederic Dias, Gérald Dibarboure, Lucile Gaultier, Johnny Johannessen, Anton Korosov, Georgy Manucharyan, Dimitris Menemenlis, Melisa Menendez, Goulven Monnier, Alexis Mouche, Frédéric Nouguier, George Nurser, Pierre Rampal, Ad Reniers, Ernesto Rodriguez, Justin Stopa, Céline Tison, Clément Ubelmann, Erik van Sebille, and Jiping Xie
Ocean Sci., 14, 337–354, https://doi.org/10.5194/os-14-337-2018, https://doi.org/10.5194/os-14-337-2018, 2018
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The Sea surface KInematics Multiscale (SKIM) monitoring mission is a proposal for a future satellite that is designed to measure ocean currents and waves. Using a Doppler radar, the accurate measurement of currents requires the removal of the mean velocity due to ocean wave motions. This paper describes the main processing steps needed to produce currents and wave data from the radar measurements. With this technique, SKIM can provide unprecedented coverage and resolution, over the global ocean.
Yao Fu, Johannes Karstensen, and Peter Brandt
Ocean Sci., 13, 531–549, https://doi.org/10.5194/os-13-531-2017, https://doi.org/10.5194/os-13-531-2017, 2017
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Meridional Ekman transport in the tropical Atlantic was estimated directly by using observed ageostrophic velocity, and indirectly by using wind stress data. The direct and indirect methods agree well with each other. The top of the pycnocline represents the Ekman depth better than the mixed layer depth and a constant depth. The Ekman heat and salt fluxes calculated from sea surface temperature and salinity or from high-resolution temperature and salinity profile data differ only marginally.
Johannes Hahn, Peter Brandt, Sunke Schmidtko, and Gerd Krahmann
Ocean Sci., 13, 551–576, https://doi.org/10.5194/os-13-551-2017, https://doi.org/10.5194/os-13-551-2017, 2017
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Recent studies have shown that the eastern tropical North Atlantic is subject to a strong decrease of the oceanic oxygen concentration in the upper 1000 m from the 1960s to today. By analyzing a broad observational data set, this study found an even stronger oxygen decrease in the upper 400 m throughout the past decade, whereas oxygen increase was found below (400–1000 m). Changes in the strength of the zonal currents are the most likely reason for the observed decadal oxygen changes.
Florian Schütte, Johannes Karstensen, Gerd Krahmann, Helena Hauss, Björn Fiedler, Peter Brandt, Martin Visbeck, and Arne Körtzinger
Biogeosciences, 13, 5865–5881, https://doi.org/10.5194/bg-13-5865-2016, https://doi.org/10.5194/bg-13-5865-2016, 2016
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Mesoscale eddies with very low–oxygen concentrations at shallow depth have been recently discovered in the eastern tropical North Atlantic. Our analysis shows that low oxygen eddies occur more frequent than expected and are found even close to the equator (8° N). From budget calculations we show that an oxygen reduction of 7 µmol/kg in the depth range of 50–150 m in the eastern tropical North Atlantic (peak reduction is 16 µmol/kg at 100 m depth) can be associated with the dispersion of these eddies.
Florian Schütte, Peter Brandt, and Johannes Karstensen
Ocean Sci., 12, 663–685, https://doi.org/10.5194/os-12-663-2016, https://doi.org/10.5194/os-12-663-2016, 2016
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We want to examine the characteristics of mesoscale eddies in the tropical northeastern Atlantic. They serve as transport agents, exporting water from the coast into the open ocean. Traditionally eddies are categorized with respect to their rotation: cyclonic and anticyclonic. But we could identify, with a combination of different satellite products, a third type called "anticyclonic mode-water eddy" transporting much larger anomalies. We propose a distinction into three classes for further studies.
L. Stramma, R. Czeschel, T. Tanhua, P. Brandt, M. Visbeck, and B. S. Giese
Ocean Sci., 12, 153–167, https://doi.org/10.5194/os-12-153-2016, https://doi.org/10.5194/os-12-153-2016, 2016
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The subsurface circulation in the eastern tropical North Atlantic OMZ is derived from velocity, float and tracer data and data assimilation results, and shows a cyclonic flow around the Guinea Dome reaching into the oxygen minimum zone. The stronger cyclonic flow around the Guinea Dome in 2009 seem to be connected to a strong Atlantic Meridional Mode (AMM) event.
A continuous deoxygenation trend of the low oxygen layer was confirmed.
Eddy influence is weak south of the Cape Verde Islands.
J. Karstensen, B. Fiedler, F. Schütte, P. Brandt, A. Körtzinger, G. Fischer, R. Zantopp, J. Hahn, M. Visbeck, and D. Wallace
Biogeosciences, 12, 2597–2605, https://doi.org/10.5194/bg-12-2597-2015, https://doi.org/10.5194/bg-12-2597-2015, 2015
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This study is the first report of the formation of dead zones in the open ocean. A combination of multiple ocean observing system elements (mooring, floats, satellites, ships) allowed us to reconstruct the generation of the dead zones and to connect the formation to enhanced respiration within mesoscale ocean eddies. The dead zones present specific threats to the ecosystem, such as the interruption of the diurnal migration of zooplankters.
P. Brandt, H. W. Bange, D. Banyte, M. Dengler, S.-H. Didwischus, T. Fischer, R. J. Greatbatch, J. Hahn, T. Kanzow, J. Karstensen, A. Körtzinger, G. Krahmann, S. Schmidtko, L. Stramma, T. Tanhua, and M. Visbeck
Biogeosciences, 12, 489–512, https://doi.org/10.5194/bg-12-489-2015, https://doi.org/10.5194/bg-12-489-2015, 2015
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Our observational study looks at the structure of the eastern tropical North Atlantic (ETNA) oxygen minimum zone (OMZ) in comparison with the less-ventilated, eastern tropical South Pacific OMZ. We quantify the OMZ’s oxygen budget composed of consumption, advection, lateral and vertical mixing. Substantial oxygen variability is observed on interannual to multidecadal timescales. The deoxygenation of the ETNA OMZ during the last decades represents a substantial imbalance of the oxygen budget.
D. Le Bars, J. V. Durgadoo, H. A. Dijkstra, A. Biastoch, and W. P. M. De Ruijter
Ocean Sci., 10, 601–609, https://doi.org/10.5194/os-10-601-2014, https://doi.org/10.5194/os-10-601-2014, 2014
T. Fischer, D. Banyte, P. Brandt, M. Dengler, G. Krahmann, T. Tanhua, and M. Visbeck
Biogeosciences, 10, 5079–5093, https://doi.org/10.5194/bg-10-5079-2013, https://doi.org/10.5194/bg-10-5079-2013, 2013
Related subject area
Approach: Numerical Models | Properties and processes: Coastal and near-shore processes
Extreme sensitivity of the northeastern Gulf of Lion (western Mediterranean) to subsurface heatwaves: physical processes and insights into effects on gorgonian populations in the summer of 2022
Coupling of numerical groundwater–ocean models to improve understanding of the coastal zone
Monsoonal influence on floating marine litter pathways in the Bay of Bengal
Coupling ocean currents and waves for seamless cross-scale modeling during Medicane Ianos
Flow patterns, hotspots, and connectivity of land-derived substances at the sea surface of Curaçao in the southern Caribbean
Wave-resolving Voronoi model of the Rouse number for sediment entrainment
The influence of a submarine canyon on the wind-driven downwelling circulation over the continental shelf
Alongshore sediment transport analysis for a semi-enclosed basin: a case study of the Gulf of Riga, the Baltic Sea
Anthropogenic pressures driving the salinity intrusion in the Guadalquivir estuary: insights from 1D numerical simulations
Application of wave–current coupled sediment transport models with variable grain properties for coastal morphodynamics: a case study of the Changhua River, Hainan
Dynamics of salt intrusion in complex estuarine networks: an idealised model applied to the Rhine–Meuse Delta
Ocean circulation, sea ice, and productivity simulated in Jones Sound, Canadian Arctic Archipelago, between 2003–2016
Influence of river runoff and precipitation on the seasonal and interannual variability of sea surface salinity in the eastern North Tropical Atlantic
A three-quantile bias correction with spatial transfer for the correction of simulated European river runoff to force ocean models
High-resolution numerical modelling of seasonal volume, freshwater, and heat transport along the Indian coast
Mechanisms and intraseasonal variability in the South Vietnam Upwelling, South China Sea: the role of circulation, tides, and rivers
Exploring water accumulation dynamics in the Pearl River estuary from a Lagrangian perspective
Exploring the tidal response to bathymetry evolution and present-day sea level rise in a channel–shoal environment
The anti-cyclonic gyre around the Qingdao cold water mass in the China marginal sea
Influence of stratification and wind forcing on the dynamics of Lagrangian residual velocity in a periodically stratified estuary
Fjord circulation permits a persistent subsurface water mass in a long, deep mid-latitude inlet
Salt intrusion dynamics in a well-mixed sub-estuary connected to a partially to well-mixed main estuary
Transport dynamics in a complex coastal archipelago
Modeling the interannual variability in Maipo and Rapel river plumes off central Chile
Short-term prediction of the significant wave height and average wave period based on the variational mode decomposition–temporal convolutional network–long short-term memory (VMD–TCN–LSTM) algorithm
Claude Estournel, Tristan Estaque, Caroline Ulses, Quentin-Boris Barral, and Patrick Marsaleix
Ocean Sci., 21, 1487–1503, https://doi.org/10.5194/os-21-1487-2025, https://doi.org/10.5194/os-21-1487-2025, 2025
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During the summer of 2022 in the eastern Gulf of Lion (NW Mediterranean), exceptionally warm temperatures were observed down to depths of 30 m, along with massive mortality of benthic species. It has been shown that these deep marine heatwaves are linked to southeasterly wind episodes, which induce deep plunges of surface water overheated by the atmospheric heatwave. These events are rare in summer, but their impact on ecosystems is dramatic and will only increase with climate change.
Jiangyue Jin, Manuel Espino, Daniel Fernàndez-Garcia, and Albert Folch
Ocean Sci., 21, 1407–1424, https://doi.org/10.5194/os-21-1407-2025, https://doi.org/10.5194/os-21-1407-2025, 2025
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Coastal zones are crucial ecological areas, yet our understanding of groundwater–ocean interactions remains limited. Ocean and groundwater models typically operate independently, with ocean models ignoring submarine groundwater discharge and groundwater models viewing the ocean as a static boundary. This separation impedes accurate simulations. By integrating these models, we can capture real-time water flow and salt movement while considering factors such as tides.
Lianne C. Harrison, Jennifer A. Graham, Piyali Chowdhury, Tiago A. M. Silva, Danja P. Hoehn, Alakes Samanta, Kunal Chakraborty, Sudheer Joseph, T. M. Balakrishnan Nair, and T. Srinivasa Kumar
Ocean Sci., 21, 1369–1393, https://doi.org/10.5194/os-21-1369-2025, https://doi.org/10.5194/os-21-1369-2025, 2025
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Particle tracking models allow us to explore pathways of floating marine litter, source to sink, between countries. This study shows the influence of seasonality for dispersal in the Bay of Bengal and how ocean current forcing impacts model performance. Most litter beached on the country of origin, but there was a greater spread shown between countries during the post-monsoon period (Oct–Jan). Results will inform future model developments as well as management of marine litter in the region.
Salvatore Causio, Seimur Shirinov, Ivan Federico, Giovanni De Cillis, Emanuela Clementi, Lorenzo Mentaschi, and Giovanni Coppini
Ocean Sci., 21, 1105–1123, https://doi.org/10.5194/os-21-1105-2025, https://doi.org/10.5194/os-21-1105-2025, 2025
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This study examines how waves and ocean currents interact during severe weather, focusing on Medicane Ianos, one of the strongest storms in the Mediterranean. Using advanced modeling, we created a unique system to simulate these interactions, capturing effects like wave-induced water levels and wave-induced effects on the vertical structure of the ocean. We validated our approach with ideal tests and real data from the storm.
Vesna Bertoncelj, Furu Mienis, Paolo Stocchi, and Erik van Sebille
Ocean Sci., 21, 945–964, https://doi.org/10.5194/os-21-945-2025, https://doi.org/10.5194/os-21-945-2025, 2025
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This study explores ocean currents around Curaçao and how land-derived substances like pollutants and nutrients travel in the water. Most substances move northwest, following the main current, but at times, ocean eddies spread them in other directions. This movement may link polluted areas to pristine coral reefs, impacting marine ecosystems. Understanding these patterns helps inform conservation and pollution management around Curaçao.
Johannes Lawen
Ocean Sci., 21, 877–896, https://doi.org/10.5194/os-21-877-2025, https://doi.org/10.5194/os-21-877-2025, 2025
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A new Voronoi-mesh-based coastal ocean model has been developed as an alternative to triangle-mesh-based models. The finite volume model has been generalized to run simulations on any mesh type, including triangle, Voronoi, Octree, structured, and mixed meshes. Wave-resolving simulations were conducted for coastal developments to resolve small scales in distributions of the Rouse number. The model has been validated using five tidal time series.
Pedro A. Figueroa, Gonzalo S. Saldías, and Susan E. Allen
Ocean Sci., 21, 643–659, https://doi.org/10.5194/os-21-643-2025, https://doi.org/10.5194/os-21-643-2025, 2025
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Submarine canyons are topographic features found along the continental slope worldwide. Here we use numerical simulations to study how a submarine canyon influences the circulation near the coast when winds moving poleward influence the region. Our results show that submarine canyons modify the circulation near the coast, causing strong velocities perpendicular to the coast. These changes can trap particles inside the canyon, an important mechanism to explain its role as a biological hotspot.
Tarmo Soomere, Mikołaj Zbigniew Jankowski, Maris Eelsalu, Kevin Ellis Parnell, and Maija Viška
Ocean Sci., 21, 619–641, https://doi.org/10.5194/os-21-619-2025, https://doi.org/10.5194/os-21-619-2025, 2025
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Seemingly interconnected beaches are often separated by human-made obstacles and natural divergence areas of sediment flux. We decompose the sedimentary shores of the Gulf of Riga into five naturally almost isolated compartments based on the analysis of wave-driven sediment flux. The western, southern, and eastern shores have quite different and fragmented sediment transport regimes. The transport rates along different shore segments show extensive interannual variations but no explicit trends.
Sara Sirviente, Juan J. Gomiz-Pascual, Marina Bolado-Penagos, Sabine Sauvage, José M. Sánchez-Pérez, and Miguel Bruno
Ocean Sci., 21, 515–535, https://doi.org/10.5194/os-21-515-2025, https://doi.org/10.5194/os-21-515-2025, 2025
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The present study utilizes a 1D hydrodynamic model to examine the impact of anthropogenic pressures on saline intrusion in the Guadalquivir estuary. Water extraction by human activities has led to elevated salinity levels throughout the estuary, thereby disrupting its natural state. A more profound understanding of these effects is essential for the protection of the estuarine ecosystems.
Yuxi Wu, Enjin Zhao, Xiwen Li, and Shiyou Zhang
Ocean Sci., 21, 473–495, https://doi.org/10.5194/os-21-473-2025, https://doi.org/10.5194/os-21-473-2025, 2025
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A comprehensive sand transfer model is proposed to study sediment dynamics in the lower reaches of the Changhua River on the island of Hainan. It captures the complex relationship between wave action, ocean currents, and sediment transport. Validated on the basis of on-site measurements, the model reveals significant sediment deposits which are significantly affected by coastal ocean currents and geological structures.
Bouke Biemond, Wouter M. Kranenburg, Ymkje Huismans, Huib E. de Swart, and Henk A. Dijkstra
Ocean Sci., 21, 261–281, https://doi.org/10.5194/os-21-261-2025, https://doi.org/10.5194/os-21-261-2025, 2025
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We study salinity in estuaries consisting of a network of channels. To this end, we develop a model that computes the flow and salinity in such systems. We use the model to quantify the mechanisms by which salt is transported into estuarine networks, the response to changes in river discharge, and the impact of depth changes. Results show that when changing the depth of channels, the effects on salt intrusion into other channels in the network can be larger than the effect on the channel itself.
Tyler Pelle, Paul G. Myers, Andrew Hamilton, Matthew Mazloff, Krista Soderlund, Lucas Beem, Donald D. Blankenship, Cyril Grima, Feras Habbal, Mark Skidmore, and Jamin S. Greenbaum
EGUsphere, https://doi.org/10.5194/egusphere-2024-3751, https://doi.org/10.5194/egusphere-2024-3751, 2024
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Here, we develop and run a high resolution ocean model of Jones Sound from 2003–2016 and characterize circulation into, out of, and within the sound as well as associated sea ice and productivity cycles. Atmospheric and ocean warming drive sea ice decline, which enhance biological productivity due to the increased light availability. These results highlight the utility of high resolution models in simulating complex waterways and the need for sustained oceanographic measurements in the sound.
Clovis Thouvenin-Masson, Jacqueline Boutin, Vincent Échevin, Alban Lazar, and Jean-Luc Vergely
Ocean Sci., 20, 1547–1566, https://doi.org/10.5194/os-20-1547-2024, https://doi.org/10.5194/os-20-1547-2024, 2024
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We focus on understanding the impact of river runoff and precipitation on sea surface salinity (SSS) in the eastern North Tropical Atlantic (e-NTA) region off northwestern Africa. By analyzing regional simulations and observational data, we find that river flows significantly influence SSS variability, particularly after the rainy season. Our findings underscore that a main source of uncertainty representing SSS variability in this region is from river runoff estimates.
Stefan Hagemann, Thao Thi Nguyen, and Ha Thi Minh Ho-Hagemann
Ocean Sci., 20, 1457–1478, https://doi.org/10.5194/os-20-1457-2024, https://doi.org/10.5194/os-20-1457-2024, 2024
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We have developed a methodology for the bias correction of simulated river runoff to force ocean models in which low, medium, and high discharges are corrected once separated at the coast. We show that the bias correction generally leads to an improved representation of river runoff in Europe. The methodology is suitable for model regions with a sufficiently high coverage of discharge observations, and it can be applied to river runoff based on climate hindcasts or climate change simulations.
Kunal Madkaiker, Ambarukhana D. Rao, and Sudheer Joseph
Ocean Sci., 20, 1167–1185, https://doi.org/10.5194/os-20-1167-2024, https://doi.org/10.5194/os-20-1167-2024, 2024
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Using a high-resolution model, we estimated the volume, freshwater, and heat transports along Indian coasts. Affected by coastal currents, transport along the eastern coast is highly seasonal, and the western coast is impacted by intraseasonal oscillations. Coastal currents and equatorial forcing determine the relation between NHT and net heat flux in dissipating heat in coastal waters. The north Indian Ocean functions as a heat source or sink based on seasonal flow of meridional heat transport.
Marine Herrmann, Thai To Duy, and Patrick Marsaleix
Ocean Sci., 20, 1013–1033, https://doi.org/10.5194/os-20-1013-2024, https://doi.org/10.5194/os-20-1013-2024, 2024
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In summer, deep, cold waters rise to the surface along and off the Vietnamese coast. This upwelling of water lifts nutrients, inducing biological activity that is important for fishery resources. Strong tides occur on the shelf off the Mekong Delta. By increasing the mixing of ocean waters and modifying currents, they are a major factor in the development of upwelling on the shelf, accounting for ~75 % of its average summer intensity.
Mingyu Li, Alessandro Stocchino, Zhongya Cai, and Tingting Zu
Ocean Sci., 20, 931–944, https://doi.org/10.5194/os-20-931-2024, https://doi.org/10.5194/os-20-931-2024, 2024
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In this study, we explored how water accumulates in a coastal estuary, a key factor affecting the estuary's environmental health and ecosystem. We revealed significant bottom accumulations influenced by plume fronts and velocity convergence, with notable seasonal variability. By analyzing trajectories, we identified subregions with distinct accumulation patterns and examined their interconnections, highlighting the substantial impact of tides and river discharge on these dynamics.
Robert Lepper, Leon Jänicke, Ingo Hache, Christian Jordan, and Frank Kösters
Ocean Sci., 20, 711–723, https://doi.org/10.5194/os-20-711-2024, https://doi.org/10.5194/os-20-711-2024, 2024
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Most coastal environments are sheltered by tidal flats and salt marshes. These habitats are threatened from drowning under sea level rise. Contrary to expectation, recent analyses in the Wadden Sea showed that tidal flats can accrete faster than sea level rise. We found that this phenomenon was facilitated by the nonlinear link between tidal characteristics and coastal bathymetry evolution. This link caused local and regional tidal adaptation with sharp increase–decrease edges at the coast.
Lin Lin, Hans von Storch, and Yang Ding
EGUsphere, https://doi.org/10.5194/egusphere-2024-1332, https://doi.org/10.5194/egusphere-2024-1332, 2024
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The Qingdao cold water mass significantly influences aquaculture in China since it is situated near the Chinese coastline. Based on 3-dimensional numerical simulation results, we find a clockwise current structure that exists around the Qingdao cold water mass; furthermore, we analyze the relationship between the clockwise current with the Qingdao cold water temperature and salinity.
Fangjing Deng, Feiyu Jia, Rui Shi, Shuwen Zhang, Qiang Lian, Xiaolong Zong, and Zhaoyun Chen
Ocean Sci., 20, 499–519, https://doi.org/10.5194/os-20-499-2024, https://doi.org/10.5194/os-20-499-2024, 2024
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Southwesterly winds impact cross-estuary flows by amplifying the eddy viscosity component during smaller tides. Moreover, they modify along-estuary gravitational circulation by diminishing both the barotropic and baroclinic components. Stratification results in contrasting sheared flows, distinguished by different dominant components compared to destratified conditions. Additionally, the eddy viscosity component is governed by various subcomponents in diverse stratified waters.
Laura Bianucci, Jennifer M. Jackson, Susan E. Allen, Maxim V. Krassovski, Ian J. W. Giesbrecht, and Wendy C. Callendar
Ocean Sci., 20, 293–306, https://doi.org/10.5194/os-20-293-2024, https://doi.org/10.5194/os-20-293-2024, 2024
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While the deeper waters in the coastal ocean show signs of climate-change-induced warming and deoxygenation, some fjords can keep cool and oxygenated waters in the subsurface. We use a model to investigate how these subsurface waters created during winter can linger all summer in Bute Inlet, Canada. We found two main mechanisms that make this fjord retentive: the typical slow subsurface circulation in such a deep, long fjord and the further speed reduction when the cold waters are present.
Zhongyuan Lin, Guang Zhang, Huazhi Zou, and Wenping Gong
Ocean Sci., 20, 181–199, https://doi.org/10.5194/os-20-181-2024, https://doi.org/10.5194/os-20-181-2024, 2024
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From 2021 to 2022, a particular sub-estuary (East River estuary) suffered greatly from an enhanced salt intrusion. We conducted observation analysis, numerical simulations, and analytical solution to unravel the underlying mechanisms. This study is of help in the investigation of salt dynamics in sub-estuaries connected to main estuaries and of implications for mitigating salt intrusion problems in the regions.
Elina Miettunen, Laura Tuomi, Antti Westerlund, Hedi Kanarik, and Kai Myrberg
Ocean Sci., 20, 69–83, https://doi.org/10.5194/os-20-69-2024, https://doi.org/10.5194/os-20-69-2024, 2024
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We studied circulation and transports in the Archipelago Sea (in the Baltic Sea) with a high-resolution hydrodynamic model. Transport dynamics show different variabilities in the north and south, so no single transect can represent transport through the whole area in all cases. The net transport in the surface layer is southward and follows the alignment of the deeper channels. In the lower layer, the net transport is southward in the northern part of the area and northward in the southern part.
Julio Salcedo-Castro, Antonio Olita, Freddy Saavedra, Gonzalo S. Saldías, Raúl C. Cruz-Gómez, and Cristian D. De la Torre Martínez
Ocean Sci., 19, 1687–1703, https://doi.org/10.5194/os-19-1687-2023, https://doi.org/10.5194/os-19-1687-2023, 2023
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Considering the relevance and impact of river discharges on the coastal environment, it is necessary to understand the processes associated with river plume dynamics in different regions and at different scales. Modeling studies focused on the eastern Pacific coast under the influence of the Humboldt Current are scarce. Here, we conduct for the first time an interannual modeling study of two river plumes off central Chile and discuss their characteristics.
Qiyan Ji, Lei Han, Lifang Jiang, Yuting Zhang, Minghong Xie, and Yu Liu
Ocean Sci., 19, 1561–1578, https://doi.org/10.5194/os-19-1561-2023, https://doi.org/10.5194/os-19-1561-2023, 2023
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Accurate wave forecasts are essential to marine engineering safety. The research designs a model with combined signal decomposition and multiple neural network algorithms to predict wave parameters. The hybrid wave prediction model has good robustness and generalization ability. The contribution of the various algorithms to the model prediction skill was analyzed by the ablation experiments. This work provides a neoteric view of marine element forecasting based on artificial intelligence.
Cited articles
Alory, G., Da-Allada, C. Y., Djakouré, S., Dadou, I., Jouanno, J., and Loemba, D. P.: Coastal Upwelling Limitation by Onshore Geostrophic Flow in the Gulf of Guinea Around the Niger River Plume, Front. Mar. Sci., 7, 607216, https://doi.org/10.3389/fmars.2020.607216, 2021.
Aloysius, N. and Saiers, J.: Simulated hydrologic response to projected changes in precipitation and temperature in the Congo River basin, Hydrol. Earth Syst. Sci., 21, 4115–4130, https://doi.org/10.5194/hess-21-4115-2017, 2017.
Alsdorf, D., Beighley, E., Laraque, A., Lee, H., Tshimanga, R., O'Loughlin, F., Mahé, G., Dinga, B., Moukandi, G., and Spencer, R. G. M.: Opportunities for hydrologic research in the Congo Basin, Rev. Geophys., 54, 378–409, https://doi.org/10.1002/2016RG000517, 2016.
Aroucha, L. C. and Schwarzkopf, F. U.: Supplementary Data to: River discharge impacts coastal Southeastern Tropical Atlantic sea surface temperature and circulation: a model-based analysis, GEOMAR Helmholtz Centre for Ocean Research Kiel [data set], https://hdl.handle.net/20.500.12085/2b927bcd-afab-4bc6-ba97-634d09435daa (last access: 10 January 2025), 2024.
Aroucha, L. C., Lübbecke, J. F., Körner, M., Imbol Koungue, R. A., and Awo, F. M.: The Influence of Freshwater Input on the Evolution of the 1995 Benguela Niño, J. Geophys. Res.-Oceans, 129, e2023JC020241, https://doi.org/10.1029/2023JC020241, 2024.
Awo, F. M., Rouault, M., Ostrowski, M., Tomety, F. S., Da-Allada, C. Y., and Jouanno, J.: Seasonal Cycle of Sea Surface Salinity in the Angola Upwelling System, J. Geophys. Res.-Oceans, 127, e2022JC018518, https://doi.org/10.1029/2022JC018518, 2022.
Ayissi, F. F. B. K., Da-Allada, C. Y., Baloïtcha, E., Worou, L. O., and Tilmes, S.: Changes in coastal upwelling in the northern Gulf of Guinea under Stratospheric Aerosol Injection, Reg. Stud. Mar. Sci., 76, 103607, https://doi.org/10.1016/j.rsma.2024.103607, 2024.
Biastoch, A., Schwarzkopf, F. U., Getzlaff, K., Rühs, S., Martin, T., Scheinert, M., Schulzki, T., Handmann, P., Hummels, R., and Böning, C. W.: Regional imprints of changes in the Atlantic Meridional Overturning Circulation in the eddy-rich ocean model VIKING20X, Ocean Sci., 17, 1177–1211, https://doi.org/10.5194/os-17-1177-2021, 2021.
Bonino, G., Masina, S., Iovino, D., Storto, A., and Tsujino, H.: Eastern Boundary Upwelling Systems response to different atmospheric forcing in a global eddy-permitting ocean model, J. Marine Syst., 197, 103178, https://doi.org/10.1016/j.jmarsys.2019.05.004, 2019.
Bordbar, M. H., Mohrholz, V., and Schmidt, M.: The relation of wind-driven coastal and offshore upwelling in the Benguela Upwelling System, J. Phys. Oceanogr., 51, 3117–3133, https://doi.org/10.1175/JPO-D-20-0297.1, 2021.
Boutin, J., Reul, N., Koehler, J., Martin, A., Catany, R., Guimbard, S., Rouffi, F., Vergely, J. L., Arias, M., Chakroun, M., Corato, G., Estella-Perez, V., Hasson, A., Josey, S., Khvorostyanov, D., Kolodziejczyk, N., Mignot, J., Olivier, L., Reverdin, G., Stammer, D., Supply, A., Thouvenin-Masson, C., Turiel, A., Vialard, J., Cipollini, P., Donlon, C., Sabia, R., and Mecklenburg, S.: Satellite-Based Sea Surface Salinity Designed for Ocean and Climate Studies, J. Geophys. Res.-Oceans, 126, e2021JC017676, https://doi.org/10.1029/2021JC017676, 2021.
Brandt, P., Bordbar, M. H., Coelho, P., Koungue, R. A. I., Körner, M., Lamont, T., Lübbecke, J. F., Mohrholz, V., Prigent, A., Roch, M., Schmidt, M., Van Der Plas, A. K., and Veitch, J.: Physical Drivers of Southwest African Coastal Upwelling and Its Response to Climate Variability and Change, in: Sustainability of Southern African Ecosystems under Global Change, vol. 248, edited by: Von Maltitz, G. P., Midgley, G. F., Veitch, J., Brümmer, C., Rötter, R. P., Viehberg, F. A., and Veste, M., Springer International Publishing, Cham, 221–257, https://doi.org/10.1007/978-3-031-10948-5_9, 2024.
Brandt, P. and Krahmann, G.: Physical oceanography (ADCP) from mooring KPO_1107, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.909911, 2019.
Brandt, P., Imbol Koungue, R. A., Krahmann, G., and Dengler, M.: Physical oceanography from mooring KPO_1235, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.962193, 2023.
Campbell, D.: The Congo River basin, in: The World's Largest Wetlands: Ecology and Conservation, edited by: Fraser, L. H. and Keddy, P. A., Cambridge University Press, Cambridge, 149–165, https://doi.org/10.1017/CBO9780511542091.006, 2005.
Chandanpurkar, H. A., Lee, T., Wang, X., Zhang, H., Fournier, S., Fenty, I., Fukumori, I., Menemenlis, D., Piecuch, C. G., Reager, J. T., Wang, O., and Worden, J.: Influence of Nonseasonal River Discharge on Sea Surface Salinity and Height, J. Adv. Model. Earth Sy., 14, e2021MS002715, https://doi.org/10.1029/2021MS002715, 2022.
Chao, Y., Farrara, J. D., Schumann, G., Andreadis, K. M., and Moller, D.: Sea surface salinity variability in response to the Congo river discharge, Cont. Shelf Res., 99, 35–45, https://doi.org/10.1016/j.csr.2015.03.005, 2015.
Chelton, D. B., deSzoeke, R. A., Schlax, M. G., El Naggar, K., and Siwertz, N.: Geographical Variability of the First Baroclinic Rossby Radius of Deformation, J. Phys. Oceanogr., 28, 433–460, https://doi.org/10.1175/1520-0485(1998)028<0433:GVOTFB>2.0.CO;2, 1998.
Dai, A. and Trenberth, K. E.: Estimates of Freshwater Discharge from Continents: Latitudinal and Seasonal Variations, J. Hydrometeorol., 3, 660–687, https://doi.org/10.1175/1525-7541(2002)003<0660:EOFDFC>2.0.CO;2, 2002.
De La Vara, A., Cabos, W., Sein, D. V., Sidorenko, D., Koldunov, N. V., Koseki, S., Soares, P. M. M., and Danilov, S.: On the impact of atmospheric vs oceanic resolutions on the representation of the sea surface temperature in the South Eastern Tropical Atlantic, Clim. Dynam., 54, 4733–4757, https://doi.org/10.1007/s00382-020-05256-9, 2020.
Denamiel, C., Budgell, W. P., and Toumi, R.: The Congo River plume: Impact of the forcing on the far-field and near-field dynamics, J. Geophys. Res.-Oceans, 118, 964–989, https://doi.org/10.1002/jgrc.20062, 2013.
Dengler, M. and Krahmann, G.: Physical oceanography (ADCP) from mooring KPO_1153, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.909913, 2019.
FAO: Fishery and Aquaculture Country Profiles, Angola, 2020, Country Profile Fact Sheets, Fisheries and Aquaculture Division, Rome, https://www.fao.org/fishery/en/facp/ago?lang= en (last access: 22 July 2024), updated 7 February 2022.
Farneti, R., Stiz, A., and Ssebandeke, J. B.: Improvements and persistent biases in the southeast tropical Atlantic in CMIP models, npj Clim. Atmos. Sci., 5, 42, https://doi.org/10.1038/s41612-022-00264-4, 2022.
Fennel, W.: Theory of the Benguela Upwelling System, J. Phys. Oceanogr., 29, 177–190, https://doi.org/10.1175/1520-0485(1999)029<0177:TOTBUS>2.0.CO;2, 1999.
Florenchie, P., Reason, C. J. C., Lutjeharms, J. R. E., Rouault, M., Roy, C., and Masson, S.: Evolution of Interannual Warm and Cold Events in the Southeast Atlantic Ocean, J. Climate, 17, 2318–2334, https://doi.org/10.1175/1520-0442(2004)017<2318:EOIWAC>2.0.CO;2, 2004.
Fong, D. A. and Geyer, W. R.: The Alongshore Transport of Freshwater in a Surface-Trapped River Plume, J. Phys. Oceanogr., 32, 957–972, https://doi.org/10.1175/1520-0485(2002)032<0957:TATOFI>2.0.CO;2, 2002.
Gammelsrød, T., Bartholomae, C. H., Boyer, D. C., Filipe, V. L. L., and O'Toole, M. J.: Intrusion of warm surface water along the Angolan-Namibian coast in February–March 1995: the 1995 Benguela Nino, S. Afr. J. Marine Sci., 19, 41–56, https://doi.org/10.2989/025776198784126719, 1998.
Gévaudan, M., Jouanno, J., Durand, F., Morvan, G., Renault, L., and Samson, G.: Influence of ocean salinity stratification on the tropical Atlantic Ocean surface, Clim. Dynam., 57, 321–340, https://doi.org/10.1007/s00382-021-05713-z, 2021.
Hopkins, J., Lucas, M., Dufau, C., Sutton, M., Stum, J., Lauret, O., and Channelliere, C.: Detection and variability of the Congo River plume from satellite derived sea surface temperature, salinity, ocean colour and sea level, Remote Sens. Environ., 139, 365–385, https://doi.org/10.1016/j.rse.2013.08.015, 2013.
Houndegnonto, O. J., Kolodziejczyk, N., Maes, C., Bourlès, B., Da-Allada, C. Y., and Reul, N.: Seasonal Variability of Freshwater Plumes in the Eastern Gulf of Guinea as Inferred From Satellite Measurements, J. Geophys. Res.-Oceans, 126, e2020JC017041, https://doi.org/10.1029/2020JC017041, 2021.
Hua, W., Zhou, L., Nicholson, S. E., Chen, H., and Qin, M.: Assessing reanalysis data for understanding rainfall climatology and variability over Central Equatorial Africa, Clim. Dynam., 53, 651–669, https://doi.org/10.1007/s00382-018-04604-0, 2019.
Huang, B., Liu, C., Banzon, V., Freeman, E., Graham, G., Hankins, B., Smith, T., and Zhang, H.-M.: Improvements of the Daily Optimum Interpolation Sea Surface Temperature (DOISST) Version 2.1, J. Climate, 34, 2923–2939, https://doi.org/10.1175/JCLI-D-20-0166.1, 2021.
Hummels, R., Imbol Koungue, R. A., Brandt, P., and Krahmann, G.: Physical oceanography from mooring KPO_1215, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.939249, 2021.
Jarre, A., Hutchings, L., Kirkman, S. P., Kreiner, A., Tchipalanga, P. C. M., Kainge, P., Uanivi, U., Van Der Plas, A. K., Blamey, L. K., Coetzee, J. C., Lamont, T., Samaai, T., Verheye, H. M., Yemane, D. G., Axelsen, B. E., Ostrowski, M., Stenevik, E. K., and Loeng, H.: Synthesis: climate effects on biodiversity, abundance and distribution of marine organisms in the Benguela, Fisheries Ocean., 24, 122–149, https://doi.org/10.1111/fog.12086, 2015.
Jarugula, S. and McPhaden, M. J.: Indian Ocean Dipole affects eastern tropical Atlantic salinity through Congo River Basin hydrology, Commun. Earth Environ., 4, 366, https://doi.org/10.1038/s43247-023-01027-6, 2023.
Jing, Z., Wang, S., Wu, L., Wang, H., Zhou, S., Sun, B., Chen, Z., Ma, X., Gan, B., and Yang, H.: Geostrophic flows control future changes of oceanic eastern boundary upwelling, Nat. Clim. Change, 13, 148–154, https://doi.org/10.1038/s41558-022-01588-y, 2023.
Kirkman, S., Blamey, L., Lamont, T., Field, J., Bianchi, G., Huggett, J., Hutchings, L., Jackson-Veitch, J., Jarre, A., Lett, C., Lipiński, M., Mafwila, S., Pfaff, M., Samaai, T., Shannon, L., Shin, Y.-J., Van Der Lingen, C., and Yemane, D.: Spatial characterisation of the Benguela ecosystem for ecosystem-based management, Afr. J. Mar. Sci., 38, 7–22, https://doi.org/10.2989/1814232X.2015.1125390, 2016.
Kopte, R., Brandt, P., Dengler, M., Tchipalanga, P. C. M., Macuéria, M., and Ostrowski, M.: The Angola Current: Flow and hydrographic characteristics as observed at 11° S: THE ANGOLA CURRENT AS OBSERVED AT 11° S, J. Geophys. Res.-Oceans, 122, 1177–1189, https://doi.org/10.1002/2016JC012374, 2017.
Körner, M., Brandt, P., and Dengler, M.: Seasonal cycle of sea surface temperature in the tropical Angolan Upwelling System, Ocean Sci., 19, 121–139, https://doi.org/10.5194/os-19-121-2023, 2023.
Körner, M., Brandt, P., Illig, S., Dengler, M., Subramaniam, A., Bachèlery, M.-L., and Krahmann, G.: Coastal trapped waves and tidal mixing control primary production in the tropical Angolan upwelling system, Sci. Adv., 10, eadj6686, https://doi.org/10.1126/sciadv.adj6686, 2024.
Koseki, S., Keenlyside, N., Demissie, T., Toniazzo, T., Counillon, F., Bethke, I., Ilicak, M., and Shen, M.-L.: Causes of the large warm bias in the Angola–Benguela Frontal Zone in the Norwegian Earth System Model, Clim. Dynam., 50, 4651–4670, https://doi.org/10.1007/s00382-017-3896-2, 2018.
Koseki, S., Giordani, H., and Goubanova, K.: Frontogenesis of the Angola–Benguela Frontal Zone, Ocean Sci., 15, 83–96, https://doi.org/10.5194/os-15-83-2019, 2019.
Krahmann, G.: Physical oceanography from mooring KPO_1106 and KPO_1107, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.870917, 2017.
Kurian, J., Li, P., Chang, P., Patricola, C. M., and Small, J.: Impact of the Benguela coastal low-level jet on the southeast tropical Atlantic SST bias in a regional ocean model, Clim. Dynam., 56, 2773–2800, https://doi.org/10.1007/s00382-020-05616-5, 2021.
Lellouche, J.-M., Greiner, E., Bourdallé Badie, R., Garric, G., Melet, A., Drévillon, M., Bricaud, C., Hamon, M., Le Galloudec, O., Regnier, C., Candela, T., Testut, C-E., Gasparin, F., Ruggiero, G., Benkiran, M., Drillet, Y. and Le Traon, P-Y.: The copernicus global 1/12 oceanic and sea ice GLORYS12 reanalysis, Front. Earth Sci., 9, 1–27, https://doi.org/10.3389/feart.2021.698876, 2021.
Levitus, S., Boyer, T. P., Conkright, M. E., Brien, T. O., Antonov, J., Stephens, C., Stathoplos, L., Johnson, D., and Gelfeld, R.: NOAA Atlas NESDIS 18, World Ocean Database 1998: Volume 1: Introduction, U.S. Gov. Printing Office, Wash., D.C., gov.noaa.nodc:0095184, 0095184 1998.
Lübbecke, J. F., Böning, C. W., Keenlyside, N. S., and Xie, S.: On the connection between Benguela and equatorial Atlantic Niños and the role of the South Atlantic Anticyclone, J. Geophys. Res., 115, 2009JC005964, https://doi.org/10.1029/2009JC005964, 2010.
Lübbecke, J. F., Brandt, P., Dengler, M., Kopte, R., Lüdke, J., Richter, I., Sena Martins, M., and Tchipalanga, P. C. M.: Causes and evolution of the southeastern tropical Atlantic warm event in early 2016, Clim, Dynam., 53, 261–274, https://doi.org/10.1007/s00382-018-4582-8, 2019.
Madec, G. and the NEMO team: NEMO ocean engine – version 3.6, Note du Pôle de modélisation, Institut Pierre-Simon Laplace (IPSL), France, 406 pp., ISSN 1288-1619, 2016.
Marchesiello, P. and Estrade, P.: Upwelling limitation by onshore geostrophic flow, J. Mar. Res., 68, 37–62, https://doi.org/10.1357/002224010793079004, 2010.
Martins, M. S. and Stammer, D.: Interannual Variability of the Congo River Plume-Induced Sea Surface Salinity, Remote Sens., 14, 1013, https://doi.org/10.3390/rs14041013, 2022.
Materia, S., Gualdi, S., Navarra, A., and Terray, L.: The effect of Congo River freshwater discharge on Eastern Equatorial Atlantic climate variability, Clim. Dynam., 39, 2109–2125, https://doi.org/10.1007/s00382-012-1514-x, 2012.
McPhaden, M. J., Jarugula, S., Aroucha, L. C., and Lübbecke, J.: Indian Ocean Dipole intensifies Benguela Niño through Congo River discharge. Commun Earth Environ 5, 779, https://doi.org/10.1038/s43247-024-01955-x, 2024.
Meade, R. H. and Emery, K. O.: Sea Level as Affected by River Runoff, Eastern United States, Science, 173, 425–428, https://doi.org/10.1126/science.173.3995.425, 1971.
Müller, O. V., McGuire, P. C., Vidale, P. L., and Hawkins, E.: River flow in the near future: a global perspective in the context of a high-emission climate change scenario, Hydrol. Earth Syst. Sci., 28, 2179–2201, https://doi.org/10.5194/hess-28-2179-2024, 2024.
Munzimi, Y. A., Hansen, M. C., and Asante, K. O.: Estimating daily streamflow in the Congo Basin using satellite-derived data and a semi-distributed hydrological model, Hydrolog. Sci. J., 64, 1472–1487, https://doi.org/10.1080/02626667.2019.1647342, 2019.
Ngakala, R. D., Alory, G., Da-Allada, C. Y., Kom, O. E., Jouanno, J., Rath, W., and Baloïtcha, E.: Joint observation–model mixed-layer heat and salt budgets in the eastern tropical Atlantic, Ocean Sci., 19, 535–558, https://doi.org/10.5194/os-19-535-2023, 2023.
Nyadjro, E. S., Foli, B. A. K., Agyekum, K. A., Wiafe, G., and Tsei, S.: Seasonal Variability of Sea Surface Salinity in the NW Gulf of Guinea from SMAP Satellite, Remote Sens. Earth Syst. Sci., 5, 83–94, https://doi.org/10.1007/s41976-021-00061-2, 2022.
Piecuch, C. G., Bittermann, K., Kemp, A. C., Ponte, R. M., Little, C. M., Engelhart, S. E., and Lentz, S. J.: River-discharge effects on United States Atlantic and Gulf coast sea-level changes, P. Natl. Acad. Sci. USA, 115, 7729–7734, https://doi.org/10.1073/pnas.1805428115, 2018.
Prigent, A. and Farneti, R.: An assessment of equatorial Atlantic interannual variability in Ocean Model Intercomparison Project (OMIP) simulations, Ocean Sci., 20, 1067–1086, https://doi.org/10.5194/os-20-1067-2024, 2024.
Reynolds, R. W., Smith, T. M., Liu, C., Chelton, D. B., Casey, K. S., and Schlax, M. G.: Daily High-Resolution-Blended Analyses for Sea Surface Temperature, J. Climate, 20, 5473–5496, https://doi.org/10.1175/2007JCLI1824.1, 2007.
Richter, I.: Climate model biases in the eastern tropical oceans: causes, impacts and ways forward, WIREs Clim. Change, 6, 345–358, https://doi.org/10.1002/wcc.338, 2015.
Rio, M.-H., Mulet, S., and Picot, N.: Beyond GOCE for the ocean circulation estimate: Synergetic use of altimetry, gravimetry, and in situ data provides new insight into geostrophic and Ekman currents, Geophys. Res. Lett., 41, 8918–8925, https://doi.org/10.1002/2014GL061773, 2014.
Roch, M., Brandt, P., Schmidtko, S., Vaz Velho, F., and Ostrowski, M.: Southeastern Tropical Atlantic Changing From Subtropical to Tropical Conditions, Front. Mar. Sci., 8, 748383, https://doi.org/10.3389/fmars.2021.748383, 2021.
Rouault, M., Illig, S., Bartholomae, C., Reason, C. J. C., and Bentamy, A.: Propagation and origin of warm anomalies in the Angola Benguela upwelling system in 2001, J. Marine Syst., 68, 473–488, https://doi.org/10.1016/j.jmarsys.2006.11.010, 2007.
Rouault, M., Illig, S., Lübbecke, J., and Koungue, R. A. I.: Origin, development and demise of the 2010–2011 Benguela Niño, J. Marine Syst., 188, 39–48, https://doi.org/10.1016/j.jmarsys.2017.07.007, 2018.
Rühs, S., Schmidt, C., Schubert, R., Schulzki, T., Schwarzkop, F., U., Le Bars, D., and Biastoch, A.: Robust estimates for the decadal evolution of Agulhas leakage from the 1960s to the 2010s, Commun. Earth Environ., 3, 318, https://doi.org/10.1038/s43247-022-00643-y, 2022.
Saha, A., Serra, N., and Stammer, D.: Growth and Decay of Northwestern Tropical Atlantic Barrier Layers, J. Geophys. Res.-Oceans, 126, e2020JC016956, https://doi.org/10.1029/2020JC016956, 2021.
Schmidt, C., Schwarzkopf, F. U., Rühs, S., and Biastoch, A.: Characteristics and robustness of Agulhas leakage estimates: an inter-comparison study of Lagrangian methods, Ocean Sci., 17, 1067–1080, https://doi.org/10.5194/os-17-1067-2021, 2021.
Schwarzkopf, F. U., Biastoch, A., Böning, C. W., Chanut, J., Durgadoo, J. V., Getzlaff, K., Harlaß, J., Rieck, J. K., Roth, C., Scheinert, M. M., and Schubert, R.: The INALT family – a set of high-resolution nests for the Agulhas Current system within global NEMO ocean/sea-ice configurations, Geosci. Model Dev., 12, 3329–3355, https://doi.org/10.5194/gmd-12-3329-2019, 2019.
Shannon, L. V., Boyd, A. J., Brundrit, G. B., and Taunton-Clark, J.: On the existence of an El Niño-type phenomenon in the Benguela System, J. Mar. Res., 44, 495–520, https://doi.org/10.1357/002224086788403105, 1986.
Small, R. J., Kurian, J., Chang, P., Xu, G., Tsujino, H., Yeager, S., Danabasoglu, G., Kim, W. M., Altuntas, A., and Castruccio, F.: Eastern Boundary Upwelling Systems in Ocean–Sea Ice Simulations Forced by CORE and JRA55-do: Mean State and Variability at the Surface, J. Climate, 37, 2821–2848, https://doi.org/10.1175/JCLI-D-23-0511.1, 2024.
SO-HYBAM: Amazon Basin water resources observation service, https://hybam.obs-mip.fr/, last access: 25 June 2024.
Sorí, R., Nieto, R., Vicente-Serrano, S. M., Drumond, A., and Gimeno, L.: A Lagrangian perspective of the hydrological cycle in the Congo River basin, Earth Syst. Dynam., 8, 653–675, https://doi.org/10.5194/esd-8-653-2017, 2017.
Sowman, M. and Cardoso, P.: Small-scale fisheries and food security strategies in countries in the Benguela Current Large Marine Ecosystem (BCLME) region: Angola, Namibia and South Africa, Mar. Policy, 34, 1163–1170, https://doi.org/10.1016/j.marpol.2010.03.016, 2010.
Tchipalanga, P., Dengler, M., Brandt, P., Kopte, R., Macuéria, M., Coelho, P., Ostrowski, M., Keenlyside, N. S. Eastern boundary circulation and hydrography off Angola: Building Angolan oceanographic capacities, B. Am. Meteorol. Soc., 99, 1589–1605, https://doi.org/10.1175/BAMS-D-17-0197.1, 2018.
Tomety, F. S., Illig, S., Ostrowski, M., Awo, F. M., Bachèlery, M.-L., Keenlyside, N., and Rouault, M.: Long-term climatological trends driving the recent warming along the Angolan and Namibian coasts, Clim. Dynam., 62, 7763–7782, https://doi.org/10.1007/s00382-024-07305-z, 2024.
Topé, G. D. A., Alory, G., Djakouré, S., Da-Allada, C. Y., Jouanno, J., and Morvan, G.: How does the Niger river warm coastal waters in the northern Gulf of Guinea?, Front. Mar. Sci., 10, 1187202, https://doi.org/10.3389/fmars.2023.1187202, 2023.
Tsujino, H., Urakawa, S., Nakano, H., Small, R. J., Kim, W. M., Yeager, S. G., Danabasoglu, G., Suzuki, T., Bamber, J. L., Bentsen, M., Böning, C. W., Bozec, A., Chassignet, E. P., Curchitser, E., Boeira Dias, F., Durack, P. J., Griffies, S. M., Harada, Y., Ilicak, M., Josey, S. A., Kobayashi, C., Kobayashi, S., Komuro, Y., Large, W. G., Le Sommer, J., Marsland, S. J., Masina, S., Scheinert, M., Tomita, H., Valdivieso, M., and Yamazaki, D.: JRA-55 based surface dataset for driving ocean–sea-ice models (JRA55-do), Ocean Modell., 130, 79–139, https://doi.org/10.1016/j.ocemod.2018.07.002, 2018.
White, R. H. and Toumi, R.: River flow and ocean temperatures: The Congo River, J. Geophys. Res.-Oceans, 119, 2501–2517, https://doi.org/10.1002/2014JC009836, 2014.
Zhang, R.-H. and Busalacchi, A. J.: Freshwater Flux (FWF)-Induced Oceanic Feedback in a Hybrid Coupled Model of the Tropical Pacific, J. Climate, 22, 853–879, https://doi.org/10.1175/2008JCLI2543.1, 2009.
Short summary
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.
The west African coastal region sustains highly productive fisheries and marine ecosystems...
