Gaetani M. auteur aut IRD Janicot Serge auteur aut IRD Vrac M. auteur aut IRD Famien A. M. auteur aut IRD Sultan Benjamin auteur aut IRD text journalArticle eng text/pdf reformatted digital access The time of emergence (TOE) of climate change is defined as the time when a new climate state emerges from a prior one. TOE assessment is particularly relevant in West Africa, a region highly threatened by climate change and urgently needing trustworthy climate predictions. In this paper, the TOE of precipitation change in West Africa is assessed for the first time, by analyzing 6 precipitation metrics (cumulated precipitation, number of wet and very wet days, onset and length of the rainy season) computed from the output of 29 state-of-the-art climate models. In West Sahel, climate conditions characterized by reduced occurrence of wet days are likely to emerge before 2036, leading to the possible emergence of a dryer climate in 2028-2052. In East Sahel, a wetter precipitation regime characterized by increased occurrence of very wet days is likely to emerge before 2054. Results do not provide a clear indication about a possible climate shift in the onset and length of the rainy season. Although uncertainty in climate model future projections still limits the robust determination of TOE locally, this study provides reliable time constraints to the expected climate shift in West Africa at the sub-regional scale, supporting adaptation measures to the future change in the precipitation regime. specialized AFRIQUE DE L'OUEST SAHEL 021 10 1 [10 ] 2020 2045-2322 https://www.documentation.ird.fr/hor/fdi:010078080 10.1038/s41598-020-63782-2 2045-2322 [F B010078080] https://www.documentation.ird.fr/hor/fdi:010078080 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers20-06/010078080.pdf IRD - Base Horizon / Pleins textes 2020-07-02 2025-02-24 fdi:010078080 fre