Stella Todzo
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Élisée Yapo Akobé
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Laboratoire des Sciences de la Matière, de l’Environnement et de l’Energie Solaire (LASMES), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Adama Diawara
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Ibrahima Diba
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Laboratoire d’Océanographie, des Sciences de l’Environnement et du Climat (LOSEC), UFR Sciences et Technologies, Université Assane SECK de Ziguinchor, Ziguinchor 270000, Senegal
Assi Louis Martial Yapo
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Unité de Formation et de Recherché Sciences et Technologies, Université Alassane Ouattara, Bouaké BP V 108, Côte d’Ivoire
Thierry C. Fotso-Nguemo
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Climate Change Research Laboratory (CCRL), National Institute of Cartography, Yaounde P.O. Box 157, Cameroon
Benjamin Kouassi
Laboratoire des Sciences de la Matière, de l’Environnement et de l’Energie Solaire (LASMES), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Fidèle Yoroba
Laboratoire des Sciences de la Matière, de l’Environnement et de l’Energie Solaire (LASMES), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Arona Diedhiou
Laboratoire Mixte International “Nexus Climat-Eau-Énergie-Agriculture en Afrique de l’Ouest et Services Climatiques” (LMI NEXUS), African Centre of Excellence on Climate Change, Biodiversity and Sustainable Agriculture (CEA CCBAD), Université Félix Houphouët-Boigny, Abidjan BP 463, Côte d’Ivoire
Institut des Géosciences de l’Environnement (IGE), Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD), Université Grenoble Alpes, Institut Polytechnique de Grenoble (Grenoble INP), 38000 Grenoble, France
This study analyses the persistence and frequency of multi-day dry and wet rainfall episodes over Côte d’Ivoire, which are quantified using CPC observations (1979–2022) and a 14-member Coordinated Regional Climate Downscaling Experiment (CORDEX)-Africa ensemble under RCP4.5 and RCP8.5. Rather than focusing solely on total rainfall, we quantify rainfall by duration and frequency of dry spells and wet episodes to capture duration-driven drought and flood risks. Historically, dry episodes last 8–15 days, with maximum annual dry spells of 25–40 days, while wet episodes persist for 3–6 days and occur 48 times per year. Projections show substantial changes in rainfall sequencing. Under RCP4.5, mean dry-episode durations increase by +1 to +2 days by mid-century and +2 to +4 days by late-century; under RCP8.5, increases reach +2 to +3 days and +3 to +6 days, respectively, with maximum dry-spell extensions of +15 to +25 days in northern regions. Wet episodes become 1–4 events per year, less frequent but lengthen by +1 to +4 days, especially along the coast under RCP8.5. These shifts suggest fewer but more persistent rainfall events, which heighten drought-related crop-water stress and multi-day flood accumulation risks. The results provide actionable insights for agriculture, hydrology and climate-risk planning by highlighting rainfall sequencing and persistence metrics not captured by traditional rainfall totals. This nuanced perspective enhances understanding of drought, flood accumulation, and agricultural risk under changing climate conditions.
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Copyright © 2026 Stella Todzo, Élisée Yapo Akobé, Adama Diawara, Ibrahima Diba, Assi Louis Martial Yapo, Thierry C. Fotso-Nguemo, Benjamin Kouassi, Fidèle Yoroba, Arona Diedhiou
This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.
