Articles | Volume 30, issue 4
https://doi.org/10.5194/hess-30-929-2026
© 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/hess-30-929-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Feb 2026
Research article |
| 17 Feb 2026
| 17 Feb 2026
Hydrological regime shifts in Sahelian watersheds: an investigation with a simple dynamical model driven by annual precipitation
Erwan Le Roux
IMT Atlantique, Lab-STICC, UMR CNRS 6285, 29238, Brest, France
Valentin Wendling
HydroSciences Montpellier (Univ. Montpellier, IMT Mines Ales, CNRS, IRD) Ales, France
Gérémy Panthou
Institut des Géosciences de l’Environnement (Univ. Grenoble Alpes, INRAE, CNRS, IRD, Grenoble INP), Grenoble, France
Océane Dubas
Institut des Géosciences de l’Environnement (Univ. Grenoble Alpes, INRAE, CNRS, IRD, Grenoble INP), Grenoble, France
Jean-Pierre Vandervaere
Institut des Géosciences de l’Environnement (Univ. Grenoble Alpes, INRAE, CNRS, IRD, Grenoble INP), Grenoble, France
Basile Hector
Institut des Géosciences de l’Environnement (Univ. Grenoble Alpes, INRAE, CNRS, IRD, Grenoble INP), Grenoble, France
Guillaume Favreau
Institut des Géosciences de l’Environnement (Univ. Grenoble Alpes, INRAE, CNRS, IRD, Grenoble INP), Grenoble, France
Jean-Martial Cohard
Institut des Géosciences de l’Environnement (Univ. Grenoble Alpes, INRAE, CNRS, IRD, Grenoble INP), Grenoble, France
Caroline Pierre
Institut d’Ecologie et des Sciences de l’Environnement de Paris (CNRS, Sorbonne Univ., Univ Paris Est Creteil, IRD, INRAE, Univ. de Paris) Paris, France
Luc Descroix
Patrimoines locaux, Environnement et Globalisation (MNHN, IRD, CNRS), Paris, France
Eric Mougin
Géosciences Environnement Toulouse (CNRS, IRD, UPS, CNES) Toulouse, France
Manuela Grippa
Géosciences Environnement Toulouse (CNRS, IRD, UPS, CNES) Toulouse, France
Laurent Kergoat
Géosciences Environnement Toulouse (CNRS, IRD, UPS, CNES) Toulouse, France
Jérôme Demarty
HydroSciences Montpellier (IRD, Univ. Montpellier, CNRS) Montpellier, France
Nathalie Rouche
HydroSciences Montpellier (IRD, Univ. Montpellier, CNRS) Montpellier, France
Jordi Etchanchu
HydroSciences Montpellier (IRD, Univ. Montpellier, CNRS) Montpellier, France
Christophe Peugeot
CORRESPONDING AUTHOR
HydroSciences Montpellier (IRD, Univ. Montpellier, CNRS) Montpellier, France
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Short summary
In hydrological science, better accounting for regime shift (abrupt and/or irreversible changes) remains a challenge that could lead to a new paradigm for the adaptation to extreme events (flood , drought). In this article, we present a simple model that can account for a hydrological regime shift in Sahelian watersheds. Based on this model, we find that the Gorouol, Dargol, Nakanbé, and Sirba watersheds have shifted during the droughts of the '70s–'80s.
In hydrological science, better accounting for regime shift (abrupt and/or irreversible changes)...
