Articles | Volume 22, issue 5
https://doi.org/10.5194/os-22-3121-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-22-3121-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Turbulence and mixing along a microtidal and stratified estuary-shelf transition
Débora Barros
Institute of Oceanography, Federal University of Rio Grande, Rio Grande, Brazil
Lauren Ross
Department of Civil and Environmental Engineering, University of Maine, Orono, USA
Carlos A. F. Schettini
CORRESPONDING AUTHOR
Institute of Oceanography, Federal University of Rio Grande, Rio Grande, Brazil
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Iván Pérez-Santos, Pamela Linford, Luis Rozas, Osvaldo Artal, Elías Pinilla, Lauren Ross, Patricio Díaz, Marcela Rojas, Guido Mancilla-Gutiérrez, Gabriel Soto, and Ivonne Montes
EGUsphere, https://doi.org/10.5194/egusphere-2026-2889, https://doi.org/10.5194/egusphere-2026-2889, 2026
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The ocean deoxygenation has accelerated globally, driven by warming and diminishing deep-water ventilation. The objective of this work is to quantify the contributions of turbulent and diapycnal mixing to water ventilation, as evidenced by upward oxygen transport from deep to subsurface layers in the northern Patagonian fjords. Our results highlight the importance of incorporating turbulence measurements into fjord studies to understand sensitivity to significant oxygen variability.
Cristian M. Rojas, Lauren Ross, Betty John Kaimathuruthy, Isabel Jalón-Rojas, Aldo Sottolichio, and Nicolas Huybrechts
Ocean Sci., 22, 1311–1327, https://doi.org/10.5194/os-22-1311-2026, https://doi.org/10.5194/os-22-1311-2026, 2026
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Although estuaries typically exhibit high suspended sediment concentrations (SSC), only a few studies have investigated how the impact of SSC on density can affect the exchange between rivers and coastal waters. Here, we use numerical models to quantify the impact of SSC on water exchange based on an estuary with large SSC and tidal range. We found that the non-consideration of SSC leads to large differences in the exchange of water that could lead to the over-quantification of water transport.
Elias Pinilla and Lauren Ross
EGUsphere, https://doi.org/10.5194/egusphere-2025-4893, https://doi.org/10.5194/egusphere-2025-4893, 2025
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Fjords connect land and ocean, exchanging nutrients and oxygen that sustain ecosystems. As climate shifts alter rainfall and winds, we probed what drives water renewal in Patagonian fjords. Using computer models that switched rivers, wind, and tides on and off, we measured their roles in exchange. Rivers provide about half of the circulation, while winds and tides modulate this baseline. As rainfall and winds change, these patterns help predict renewal failures and low-oxygen risk.
Dirk S. van Maren, Christian Maushake, Jan-Willem Mol, Daan van Keulen, Jens Jürges, Julia Vroom, Henk Schuttelaars, Theo Gerkema, Kirstin Schulz, Thomas H. Badewien, Michaela Gerriets, Andreas Engels, Andreas Wurpts, Dennis Oberrecht, Andrew J. Manning, Taylor Bailey, Lauren Ross, Volker Mohrholz, Dante M. L. Horemans, Marius Becker, Dirk Post, Charlotte Schmidt, and Petra J. T. Dankers
Earth Syst. Sci. Data, 15, 53–73, https://doi.org/10.5194/essd-15-53-2023, https://doi.org/10.5194/essd-15-53-2023, 2023
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This paper reports on the main findings of a large measurement campaign aiming to better understand how an exposed estuary (the Ems Estuary on the Dutch–German border) interacts with a tidal river (the lower Ems River). Eight simultaneously deployed ships measuring a tidal cycle and 10 moorings collecting data throughout a spring–neap tidal cycle have produced a dataset providing valuable insight into processes determining exchange of water and sediment between the two systems.
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Short summary
Coastal waters often show vertical stratification because lighter freshwater overlies denser seawater. Mixing requires kinetic energy, generating turbulence that is difficult to quantify. We investigate the transition from a confined channel to the adjacent coast, where outflow spreads over denser water. Measurements of velocity, salinity, and turbulence show that small geometric changes enhance mixing, especially near the mouth, reaching levels comparable to tide-dominated systems.
Coastal waters often show vertical stratification because lighter freshwater overlies denser...