Profound changes in tropical North African wetland extent and their socio-ecological consequences

Authors: Andy Hardy, Gregory Oakes, Peter Bunting, Mori Diallo, Lorentzo Gaffi, Lammert Hilarides, Edmund Kuto, Boubacar Youssouf, Christopher Taylor

Historically defined by climate variability and recurrent droughts, the Sahel-East Africa region has undergone a profound hydrological transformation, yet the regional impact of recent extreme climatic events remains poorly understood. Using high-frequency 30 m Landsat analysis, we reconstruct a decade of inundation dynamics (2014–2023) across this trans-continental domain, revealing an 86% surge in wetland extent. This expansion represents a large-scale transition from ephemeral to seasonal wetlands, likely triggered by the record-breaking positive Indian Ocean Dipole in late 2019 affecting much of East Africa, and a more northerly latitude of the Intertropical Convergence Zone during recent Sahelian rainy seasons. We identify focal areas of extreme expansion in inundated extent that intersect directly with major capital cities, refugee camps, and critical agricultural schemes. These results demonstrate that short-term climatic shocks can permanently reset regional flood baselines, necessitating an urgent re-evaluation of flood vulnerability and water management across the Sahel and East Africa.

 

Description of Files

Bi-Monthly_Refined_Outputs :

Bi-Monthly classiied outputs showing areas of: Inundated Vegetation - Class 1, Open Water - Class 4, Other Dry Landcover - Class 3.

Post_Classification_Refinement_Aux_Data:

Datasets used in the post classification refinement proccedure described in (Hardy et al, 2026 - In Review), supplimentary methods section.