Peugeot Christophe auteur aut IRD Wendling V. auteur aut IRD Le Roux E. auteur aut IRD Panthou G. auteur aut IRD Hector Basile auteur aut IRD Rouché Nathalie auteur aut IRD Crespin-Boucaud Arthur auteur aut IRD Favreau Guillaume auteur aut IRD Dobi F. B. auteur aut IRD Cohard J. M. auteur aut IRD Demarty Jérome auteur aut IRD Descroix Luc auteur aut IRD Etchanchu Jordi auteur aut IRD Grippa M. auteur aut IRD Hiernaux P. auteur aut IRD Warzagan A. I. auteur aut IRD Kergoat L. auteur aut IRD Abdou M. M. auteur aut IRD Mougin E. auteur aut IRD Pierre C. auteur aut IRD Rajot Jean-Louis auteur aut IRD Vandervaere J. P. auteur aut IRD Vischel T. auteur aut IRD Lebel Thierry auteur aut IRD text journalArticle eng text/pdf reformatted digital access Using ground-based meteorological, hydrological and land cover datasets from 1950 to 2015, we provide evidence that the increase in runoff observed in the semi-arid central Sahel (West Africa) since the 1970-1995 drought is a shift between alternative stable states of low and high runoff. We propose a conceptual model, governed by feedback loops between vegetation and surface runoff, which describes the stabilising mechanisms of each state and the basin-scale impact of local shifts. While the drought was likely the trigger for the shift, land clearing and rainfall intensification may have reinforced it. Due to wetter conditions and greater resilience, other basins further south did not shift. Our study suggests that the shift towards higher runoff is due to surface processes playing a dominant role in this region, with minimal contribution from subsurface processes. This regime shift framework offers a promising perspective on understanding long-term hydrological changes. specialized AFRIQUE DE L'OUEST MALI BURKINA FASO NIGER BANIN NIGERIA ZONE SAHELIENNE ZONE SOUDANIENNE 062 021 17 1 6162 [14 p.] 2026 https://www.documentation.ird.fr/hor/fdi:010097610 10.1038/s41467-026-72648-6 [F B010097610] https://www.documentation.ird.fr/hor/fdi:010097610 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2026-08/010097610.pdf IRD - Base Horizon / Pleins textes 2026-08-06 2026-08-19 fdi:010097610 fre