Articles | Volume 21, issue 3
https://doi.org/10.5194/os-21-989-2025
© 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-21-989-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
13 Jun 2025
Research article |
| 13 Jun 2025
| 13 Jun 2025
Turbulent erosion of a subducting intrusion in the Western Mediterranean Sea
Giovanni Testa
CORRESPONDING AUTHOR
Institute of Marine Sciences, Italian National Research Council (CNR-ISMAR), Venice, Italy
Mathieu Dever
Woods Hole Oceanographic Institution, Woods Hole, 02543 MA, USA
RBR, Ottawa, Canada
Mara Freilich
Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, USA
Amala Mahadevan
Woods Hole Oceanographic Institution, Woods Hole, 02543 MA, USA
T. M. Shaun Johnston
Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
Lorenzo Pasculli
Institute of Marine Sciences, Italian National Research Council (CNR-ISMAR), Venice, Italy
Department of Environmental Sciences, Informatics and Statistics, Ca' Foscari University of Venice, Via Torino 155, 30172 Mestre, Italy
Francesco M. Falcieri
Institute of Marine Sciences, Italian National Research Council (CNR-ISMAR), Venice, Italy
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M. M. Omand and A. Mahadevan
Biogeosciences, 12, 3273–3287, https://doi.org/10.5194/bg-12-3273-2015, https://doi.org/10.5194/bg-12-3273-2015, 2015
Related subject area
Approach: In situ Observations | Properties and processes: Internal waves, turbulence and mixing
Overlapping turbulent boundary layers in an energetic coastal sea
Dissipation ratio and eddy diffusivity of turbulent and salt finger mixing derived from microstructure measurements
Internal-wave-induced dissipation rates in the Weddell Sea Bottom Water gravity current
Technical note: Spectral slopes in a deep, weakly stratified ocean and coupling between sub-mesoscale motion and small-scale mechanisms
Enhanced bed shear stress and mixing in the tidal wake of an offshore wind turbine monopile
A global summary of seafloor topography influenced by internal-wave induced turbulent water mixing
Parameter Sensitivity Study of Energy Transfer Between Mesoscale Eddies and Wind-Induced Near-Inertial Oscillations
Turbulent dissipation from AMAZOMIX off the Amazon shelf along internal tides paths
Internal-tide vertical structure and steric sea surface height signature south of New Caledonia revealed by glider observations
Observations of strong turbulence and mixing impacting water exchange between two basins in the Baltic Sea
Arnaud F. Valcarcel, Craig L. Stevens, Joanne M. O'Callaghan, and Sutara H. Suanda
Ocean Sci., 21, 965–987, https://doi.org/10.5194/os-21-965-2025, https://doi.org/10.5194/os-21-965-2025, 2025
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This paper describes underwater robotic measurements in an energetic strait. The data show how energy is transferred from winds and tides to turbulent processes. Boundary layers of strong turbulence affected the water from surface to seafloor across an unusually deep extent, except when fresher or warmer waters moved into the region. Numerical models revealed that turbulent energy transport allowed boundary layers to interact. This phenomenon may impact the biological structure of coastal seas.
Jianing Li, Qingxuan Yang, and Hui Sun
Ocean Sci., 21, 829–849, https://doi.org/10.5194/os-21-829-2025, https://doi.org/10.5194/os-21-829-2025, 2025
Short summary
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The Osborn relation is widely used to estimate the diapycnal mixing rate, but its accuracy is questioned due to the assumed constant dissipation ratio (Γ) without identifying mixing types. We identify a salt finger and turbulence in the western Pacific and midlatitude Atlantic, finding that Γ is highly variable and related to turbulence parameters, through which we improve mixing rate estimates. Identifying mixing types and refining Γ are necessary to improve mixing parameterization accuracy.
Ole Pinner, Friederike Pollmann, Markus Janout, Gunnar Voet, and Torsten Kanzow
Ocean Sci., 21, 701–726, https://doi.org/10.5194/os-21-701-2025, https://doi.org/10.5194/os-21-701-2025, 2025
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The Weddell Sea Bottom Water gravity current transports dense water from the continental shelf to the deep sea and is crucial for the formation of new deep-sea water. Building on vertical profiles and time series measured in the northwestern Weddell Sea, we apply three methods to distinguish turbulence caused by internal waves from that by other sources. We find that in the upper part of the gravity current, internal waves are important for the mixing of less dense water down into the current.
Hans van Haren
Ocean Sci., 21, 555–565, https://doi.org/10.5194/os-21-555-2025, https://doi.org/10.5194/os-21-555-2025, 2025
Short summary
Short summary
Ocean circulations include small-scale processes like transport through sub-mesoscale eddies and turbulence by internal wave breaking. Knowledge is lacking on the interaction between the different processes. In deep, weakly stratified waters, continuous spectral slopes are observed that extend from sub-mesoscales across the internal wave band to the turbulence range. Such correspondence is suggested as being a potential feedback mechanism stabilizing large-scale ocean circulations.
Martin J. Austin, Christopher A. Unsworth, Katrien J. J. Van Landeghem, and Ben J. Lincoln
Ocean Sci., 21, 81–91, https://doi.org/10.5194/os-21-81-2025, https://doi.org/10.5194/os-21-81-2025, 2025
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Novel hydrodynamic observations 40 m from an offshore wind turbine monopile show that the turbulent tidal lee wake doubles the drag acting on the seabed, potentially enhancing sediment transport and impacting the seabed habitat and the organisms that utilise it. It also enhances the vertical mixing of the water column, which drives the transport of heat, nutrients and oxygen. As offshore wind farms rapidly expand into deeper waters, array-scale wakes may have significant ecological impacts.
Hans van Haren and Henk de Haas
EGUsphere, https://doi.org/10.5194/egusphere-2024-3603, https://doi.org/10.5194/egusphere-2024-3603, 2024
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Turbulent water motions are important for the exchange of momentum, heat, nutrients, and suspended matter in the deep-sea. The shape of marine topography influences most water turbulence via breaking internal waves at ‘critically’ sloping seafloors. In this paper, the concept of critical slopes is revisited from a global internal wave-turbulence viewpoint using seafloor topography- and moored temperature sensor data. Potential robustness of the seafloor-internal wave interaction is discussed.
Yu Zhang, Jintao Gu, Shengli Chen, Jianyu Hu, Jinyu Sheng, and Jiuxing Xing
EGUsphere, https://doi.org/10.5194/egusphere-2024-3457, https://doi.org/10.5194/egusphere-2024-3457, 2024
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Current observations at two moorings in the northern South China Sea reveal that mesoscale eddies can transfer energy with near-inertial oscillations (NIOs). Numerical experiments are conducted to investigate important parameters affecting energy transfer between mesoscale eddies and NIOs, which demonstrate that the energy transferred by mesoscale eddies is larger with stronger winds and higher strength of the mesoscale eddy. Anticyclonic eddies can transfer more energy than cyclonic eddies.
Fabius Kouogang, Ariane Koch-Larrouy, Jorge Magalhaes, Alex Costa da Silva, Daphne Kerhervé, Arnaud Bertrand, Evan Cervelli, Jean-François Ternon, Pierre Rousselot, James Lee, Marcelo Rollnic, and Moacyr Araujo
EGUsphere, https://doi.org/10.5194/egusphere-2024-2548, https://doi.org/10.5194/egusphere-2024-2548, 2024
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The first time direct measurements of turbulent dissipation from AMAZOMIX revealed high energy dissipations within [10-6,10-4] W.kg-1 caused at 65 % apart from internal tides in their generation zone, and [10-8,10-7] W.kg-1 caused at 50.4 % by mean circulation of surrounding water masses far fields. Finally, estimates of nutrient fluxes showed a very high flux of nitrate ([10-2, 10-0] mmol N m-2.s-1) and phosphate ([10-3, 10-1] mmol P m-2.s-1), due to both processes in Amazon region.
Arne Bendinger, Sophie Cravatte, Lionel Gourdeau, Luc Rainville, Clément Vic, Guillaume Sérazin, Fabien Durand, Frédéric Marin, and Jean-Luc Fuda
Ocean Sci., 20, 945–964, https://doi.org/10.5194/os-20-945-2024, https://doi.org/10.5194/os-20-945-2024, 2024
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A unique dataset of glider observations reveals tidal beams south of New Caledonia – an internal-tide-generation hot spot in the southwestern tropical Pacific. Observations are in good agreement with numerical modeling output, highlighting the glider's capability to infer internal tides while assessing the model's realism of internal-tide dynamics. Discrepancies are in large part linked to eddy–internal-tide interactions. A methodology is proposed to deduce the internal-tide surface signature.
Julia Muchowski, Martin Jakobsson, Lars Umlauf, Lars Arneborg, Bo Gustafsson, Peter Holtermann, Christoph Humborg, and Christian Stranne
Ocean Sci., 19, 1809–1825, https://doi.org/10.5194/os-19-1809-2023, https://doi.org/10.5194/os-19-1809-2023, 2023
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We show observational data of highly increased mixing and vertical salt flux rates in a sparsely sampled region of the northern Baltic Sea. Co-located acoustic observations complement our in situ measurements and visualize turbulent mixing with high spatial resolution. The observed mixing is generally not resolved in numerical models of the area but likely impacts the exchange of water between the adjacent basins as well as nutrient and oxygen conditions in the Bothnian Sea.
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Short summary
In the Western Alboran Gyre, waters from the Atlantic and Mediterranean meet, creating density differences that cause some water to sink, affecting ocean ventilation and nutrient cycles. We collected data showing patches of water with higher oxygen and chlorophyll levels moving towards the gyre's center, with active mixing at their edges. This mixing diluted the patches, and other factors like water density and light penetration likely played a role in these dynamics.
In the Western Alboran Gyre, waters from the Atlantic and Mediterranean meet, creating density...
