Articles | Volume 21, issue 2
https://doi.org/10.5194/os-21-727-2025
© 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-21-727-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Apr 2025
Research article |
| 03 Apr 2025
| 03 Apr 2025
An estimate of the eddy diffusivity tensor from observed and simulated Lagrangian trajectories in the Benguela Upwelling System
Institute of Environmental Physics, University of Bremen, Bremen, Germany
Birte Gülk
LOCEAN, Sorbonne Université–CNRS–IRD–MNHN, Paris, France
Julia Dräger-Dietel
Institut für Meereskunde, Universität Hamburg, Hamburg, Germany
Alexa Griesel
Institut für Meereskunde, Universität Hamburg, Hamburg, Germany
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Short summary
The study explores how unresolved motions in the Benguela upwelling region affect diffusivity estimates and the need for full diffusivity tensors in models. Using a scalar for lateral mixing can be inaccurate due to directional mixing. Analysis of buoys and simulations shows that diffusivity from particle pairs is lower than expected and that removing the mean flow improves estimates. The study shows the importance of full diffusivity tensors for better model mixing and reducing warm biases in models.
The study explores how unresolved motions in the Benguela upwelling region affect diffusivity...
