Articles | Volume 22, issue 2
https://doi.org/10.5194/os-22-1105-2026
© 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-22-1105-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Apr 2026
Research article |
| 01 Apr 2026
| 01 Apr 2026
Coastal circulation and dispersion of passive tracers in the Red River plume region: unveiling seasonal- and intra-seasonal variability
Thanh Huyen Tran
Laboratory of Oceanology and Geosciences (LOG), UMR 8187, Univ. 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. Littoral Côte d'Opale, CNRS, Univ. Lille, IRD, Wimereux, France
Dylan Dumas
MIO, Université de Toulon, Aix-Marseille Univ., CNRS, IRD, Toulon, France
Charles-Antoine Guerin
MIO, Université de Toulon, Aix-Marseille Univ., CNRS, IRD, Toulon, France
Sylvain Ouillon
IRD, Van Phuc diplomatic Compound, 298 Kim Ma, Ngoc Ha, Hanoi, Vietnam
University of Science, Vietnam National University, Hanoi, Vietnam
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Short summary
The research used high-resolution high-frequency radar data and surface drifters to investigate surface circulation patterns in the Red River plume area of the Gulf of Tonkin from August to December 2024. Particle spreading intensified and became highly scattered rather than remaining clustered as particles approached river outflows and eddy-dominated zones. The study shows that material transport and spreading became remarkably faster during Typhoon Yagi 2024 than under normal conditions.
The research used high-resolution high-frequency radar data and surface drifters to investigate...
