Seasonal and interannual drivers of <i>Sargassum</i> inundations in the Northern Gulf of Guinea

Thouvenin-Masson, Clovis; Jouanno, Julien

doi:10.5194/os-22-2835-2026

Articles | Volume 22, issue 5

https://doi.org/10.5194/os-22-2835-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/os-22-2835-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 22, issue 5

Research article

|

16 Sep 2026

Research article |

| 16 Sep 2026

Seasonal and interannual drivers of Sargassum inundations in the Northern Gulf of Guinea

Clovis Thouvenin-Masson and Julien Jouanno

Data sets

Cartes de répartition des couvertures de Sargasses dérivées de MODIS sur l'Atlantique L. Berline and J. Descloitres https://doi.org/10.12770/8fe1cdcb-f4ea-4c81-8543-50f0b39b4eca

Global Ocean Physics Reanalysis Mercator Ocean International https://doi.org/10.48670/moi-00021

Model code and software

Sargassum distribution model based on the NEMO ocean modelling platform J. Jouanno and R. Benshila https://doi.org/10.5281/zenodo.4275901

Short summary

We studied why floating Sargassum seaweed repeatedly reaches the northern Gulf of Guinea, where it affects coastal activities such as fishing. By combining satellite observations with computer simulations, we found two main arrival seasons, in spring and autumn. Most events are driven by seaweed transported from the eastern tropical Atlantic, while winds push it toward the coast and beaching limits how long it persists. Year-to-year changes are linked to shifts in Atlantic climate.