eng Science and Education Publishing American Journal of Environmental Protection 2328-7233 2022-05-08 10 1 41 46 10.12691/env-10-1-5 ENV20221015 article Moussa Diakhat¨¦ moussa.diakhate@uam.edu.sn 1 2 Mamadou Lamine Mbaye 3 Ibrahima Camara 3 Mamadou Ba?lo Barry 3 4 Ecole Sup¨¦rieure des Sciences et Techniques de l¡¯Ing¨¦nieur (ESTI), Universit¨¦ Amadou Mahtar Mbow (UAM), Dakar, Senegal Laboratoire d¡¯Oc¨¦anographie, des Sciences de l¡¯Environnement et du Climat (LOSEC), UFR Sciences et Technologies, Universit¨¦ Assane Seck de Ziguinchor (UASZ), Ziguinchor, Senegal This study provides a synthetic analysis of the current state and the future changes in the rainfall annual cycle over the Senegal river basin (SRB) using observed data from the SIEREM (Système d¡¯Informations Environnementales sur les Ressources en Eau et leur Modélisation) database, and 29 CMIP5 (Climate Model Intercomparison Project 5) simulations. The output of the models are bias-corrected using the observational data as a reference. This process revealed the added value of the bias correction that has reduced considerably the biases in the amplitude of the rainfall annual cycle. With the corrected simulations, future changes (by 2050 and 2100) in the seasonal variation of rainfall are analyzed under two scenarios (RCP4.5 and RCP8.5), and over each of the 7 sub-basins (SB) of the SRB. A decrease of about 20% in rainfall amount over the first phase of the monsoon season (May-August) is expected under the scenario RCP8.5, leading to a displacement of the monsoon peak from August to September. This change is shown to affect the least humid SBs (SB 3-7). http://pubs.sciepub.com/env/10/1/5/env-10-1-5.pdf Senegal River Basin rainfall seasonal cycle climate models bias correction future projections