Articles | Volume 20, issue 4
https://doi.org/10.5194/os-20-1013-2024
© Author(s) 2024. 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-20-1013-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Aug 2024
Research article |
| 22 Aug 2024
| 22 Aug 2024
Mechanisms and intraseasonal variability in the South Vietnam Upwelling, South China Sea: the role of circulation, tides, and rivers
Université de Toulouse, LEGOS (CNES/CNRS/IRD/UT3), Toulouse, France
Thai To Duy
Institute of Oceanography (IO), Vietnam Academy of Science and Technology (VAST), Nha Trang, Vietnam
Patrick Marsaleix
Université de Toulouse, LEGOS (CNES/CNRS/IRD/UT3), Toulouse, France
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Thanh Huyen Tran, Alexei Sentchev, Thai To Duy, Marine Herrmann, Sylvain Ouillon, and Kim Cuong Nguyen
Ocean Sci., 21, 1–18, https://doi.org/10.5194/os-21-1-2025, https://doi.org/10.5194/os-21-1-2025, 2025
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For the first time, high-resolution surface current data from high-frequency radar have been obtained along the central and southern coasts of Vietnam, and combined with a modelling approach, this is helping scientists to understand coastal processes. The research showed that the surface circulation is driven not only by winds, but also by other factors. This can enrich public knowledge of the coastal dynamics that govern other environmental impacts along the coasts.
Adrien Garinet, Marine Herrmann, Patrick Marsaleix, and Juliette Pénicaud
Geosci. Model Dev., 17, 6967–6986, https://doi.org/10.5194/gmd-17-6967-2024, https://doi.org/10.5194/gmd-17-6967-2024, 2024
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Mixing is a crucial aspect of the ocean, but its accurate representation in computer simulations is made challenging by errors that result in unwanted mixing, compromising simulation realism. Here we illustrate the spurious effect that tides can have on simulations of south-east Asia. Although they play an important role in determining the state of the ocean, they can increase numerical errors and make simulation outputs less realistic. We also provide insights into how to reduce these errors.
Ngoc B. Trinh, Marine Herrmann, Caroline Ulses, Patrick Marsaleix, Thomas Duhaut, Thai To Duy, Claude Estournel, and R. Kipp Shearman
Geosci. Model Dev., 17, 1831–1867, https://doi.org/10.5194/gmd-17-1831-2024, https://doi.org/10.5194/gmd-17-1831-2024, 2024
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A high-resolution model was built to study the South China Sea (SCS) water, heat, and salt budgets. Model performance is demonstrated by comparison with observations and simulations. Important discards are observed if calculating offline, instead of online, lateral inflows and outflows of water, heat, and salt. The SCS mainly receives water from the Luzon Strait and releases it through the Mindoro, Taiwan, and Karimata straits. SCS surface interocean water exchanges are driven by monsoon winds.
Marine Herrmann, Thai To Duy, and Claude Estournel
Ocean Sci., 19, 453–467, https://doi.org/10.5194/os-19-453-2023, https://doi.org/10.5194/os-19-453-2023, 2023
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The South Vietnam upwelling develops in summer along and off the Vietnamese coast. It brings cold and nutrient-rich waters to the surface, allowing photosynthesis essential to marine ecosystems and fishing resources. We show here that its daily variations are mainly due to the wind, thus predictable, in the southern shelf and coastal regions. However, they are more chaotic in the offshore area, and especially in the northern area, due to the influence of eddies of a highly chaotic nature.
Thai To Duy, Marine Herrmann, Claude Estournel, Patrick Marsaleix, Thomas Duhaut, Long Bui Hong, and Ngoc Trinh Bich
Ocean Sci., 18, 1131–1161, https://doi.org/10.5194/os-18-1131-2022, https://doi.org/10.5194/os-18-1131-2022, 2022
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The South Vietnam Upwelling develops in the coastal and offshore regions of the southwestern South China Sea under the influence of summer monsoon winds. Cold, nutrient-rich waters rise to the surface, where photosynthesis occurs and is essential for fishing activity. We have developed a very high-resolution model to better understand the factors that drive the variability of this upwelling at different scales: daily chronology to summer mean of wind and mesoscale to regional circulation.
Violaine Piton, Marine Herrmann, Florent Lyard, Patrick Marsaleix, Thomas Duhaut, Damien Allain, and Sylvain Ouillon
Geosci. Model Dev., 13, 1583–1607, https://doi.org/10.5194/gmd-13-1583-2020, https://doi.org/10.5194/gmd-13-1583-2020, 2020
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Consequences of tidal dynamics on hydro-sedimentary processes are a recurrent issue in estuarine and coastal processes studies, and accurate tidal solutions are a prerequisite for modeling sediment transport. This study presents the implementation and optimization of a model configuration in terms of bathymetry and bottom friction and assess the influence of these parameters on tidal solutions, in a macro-tidal environment: the Gulf of Tonkin (Vietnam).
Thanh Huyen Tran, Alexei Sentchev, Thai To Duy, Marine Herrmann, Sylvain Ouillon, and Kim Cuong Nguyen
Ocean Sci., 21, 1–18, https://doi.org/10.5194/os-21-1-2025, https://doi.org/10.5194/os-21-1-2025, 2025
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For the first time, high-resolution surface current data from high-frequency radar have been obtained along the central and southern coasts of Vietnam, and combined with a modelling approach, this is helping scientists to understand coastal processes. The research showed that the surface circulation is driven not only by winds, but also by other factors. This can enrich public knowledge of the coastal dynamics that govern other environmental impacts along the coasts.
Claude Estournel, Tristan Estaque, Caroline Ulses, Quentin-Boris Barral, and Patrick Marsaleix
EGUsphere, https://doi.org/10.5194/egusphere-2024-3880, https://doi.org/10.5194/egusphere-2024-3880, 2024
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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 south-easterly 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.
Adrien Garinet, Marine Herrmann, Patrick Marsaleix, and Juliette Pénicaud
Geosci. Model Dev., 17, 6967–6986, https://doi.org/10.5194/gmd-17-6967-2024, https://doi.org/10.5194/gmd-17-6967-2024, 2024
Short summary
Short summary
Mixing is a crucial aspect of the ocean, but its accurate representation in computer simulations is made challenging by errors that result in unwanted mixing, compromising simulation realism. Here we illustrate the spurious effect that tides can have on simulations of south-east Asia. Although they play an important role in determining the state of the ocean, they can increase numerical errors and make simulation outputs less realistic. We also provide insights into how to reduce these errors.
Ngoc B. Trinh, Marine Herrmann, Caroline Ulses, Patrick Marsaleix, Thomas Duhaut, Thai To Duy, Claude Estournel, and R. Kipp Shearman
Geosci. Model Dev., 17, 1831–1867, https://doi.org/10.5194/gmd-17-1831-2024, https://doi.org/10.5194/gmd-17-1831-2024, 2024
Short summary
Short summary
A high-resolution model was built to study the South China Sea (SCS) water, heat, and salt budgets. Model performance is demonstrated by comparison with observations and simulations. Important discards are observed if calculating offline, instead of online, lateral inflows and outflows of water, heat, and salt. The SCS mainly receives water from the Luzon Strait and releases it through the Mindoro, Taiwan, and Karimata straits. SCS surface interocean water exchanges are driven by monsoon winds.
Marine Herrmann, Thai To Duy, and Claude Estournel
Ocean Sci., 19, 453–467, https://doi.org/10.5194/os-19-453-2023, https://doi.org/10.5194/os-19-453-2023, 2023
Short summary
Short summary
The South Vietnam upwelling develops in summer along and off the Vietnamese coast. It brings cold and nutrient-rich waters to the surface, allowing photosynthesis essential to marine ecosystems and fishing resources. We show here that its daily variations are mainly due to the wind, thus predictable, in the southern shelf and coastal regions. However, they are more chaotic in the offshore area, and especially in the northern area, due to the influence of eddies of a highly chaotic nature.
Thai To Duy, Marine Herrmann, Claude Estournel, Patrick Marsaleix, Thomas Duhaut, Long Bui Hong, and Ngoc Trinh Bich
Ocean Sci., 18, 1131–1161, https://doi.org/10.5194/os-18-1131-2022, https://doi.org/10.5194/os-18-1131-2022, 2022
Short summary
Short summary
The South Vietnam Upwelling develops in the coastal and offshore regions of the southwestern South China Sea under the influence of summer monsoon winds. Cold, nutrient-rich waters rise to the surface, where photosynthesis occurs and is essential for fishing activity. We have developed a very high-resolution model to better understand the factors that drive the variability of this upwelling at different scales: daily chronology to summer mean of wind and mesoscale to regional circulation.
Violaine Piton, Marine Herrmann, Florent Lyard, Patrick Marsaleix, Thomas Duhaut, Damien Allain, and Sylvain Ouillon
Geosci. Model Dev., 13, 1583–1607, https://doi.org/10.5194/gmd-13-1583-2020, https://doi.org/10.5194/gmd-13-1583-2020, 2020
Short summary
Short summary
Consequences of tidal dynamics on hydro-sedimentary processes are a recurrent issue in estuarine and coastal processes studies, and accurate tidal solutions are a prerequisite for modeling sediment transport. This study presents the implementation and optimization of a model configuration in terms of bathymetry and bottom friction and assess the influence of these parameters on tidal solutions, in a macro-tidal environment: the Gulf of Tonkin (Vietnam).
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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.
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Short summary
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.
In summer, deep, cold waters rise to the surface along and off the Vietnamese coast. This...
