Articles | Volume 21, issue 1
https://doi.org/10.5194/os-21-1-2025
© 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-21-1-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
07 Jan 2025
Research article |
| 07 Jan 2025
| 07 Jan 2025
Surface circulation characterization along the middle southern coastal region of Vietnam from high-frequency radar and numerical modeling
Thanh Huyen Tran
CORRESPONDING AUTHOR
Laboratory of Oceanology and Geosciences (LOG), UMR 8187, Univ. du Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, Wimereux, France
Land–Ocean–Atmosphere Regional Coupled System Study Center (LOTUS), University of Science and Technology of Hanoi (USTH), Hanoi, Vietnam
Alexei Sentchev
Laboratory of Oceanology and Geosciences (LOG), UMR 8187, Univ. du Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, Wimereux, France
Thai To Duy
Institute of Oceanography, Vietnam Academy of Science and Technology (VAST), Nha Trang, Vietnam
Marine Herrmann
Laboratory of Space Geophysical and Oceanographic Studies (LEGOS), UMR 5566, IRD, CNES, CNRS, UPS, Toulouse, France
Sylvain Ouillon
Land–Ocean–Atmosphere Regional Coupled System Study Center (LOTUS), University of Science and Technology of Hanoi (USTH), Hanoi, Vietnam
Laboratory of Space Geophysical and Oceanographic Studies (LEGOS), UMR 5566, IRD, CNES, CNRS, UPS, Toulouse, France
Kim Cuong Nguyen
Department of Marine Science and Technology, University of Science (HUS), Vietnam National University, Hanoi, Vietnam
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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.
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Short summary
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.
For the first time, high-resolution surface current data from high-frequency radar have been...
