Theoretical and Applied Climatology

, Volume 113, Issue 1–2, pp 351–362

Interannual variability of rainfall over the Sahel based on multiple regional climate models simulations

  • Ismaila Diallo
  • Mouhamadou B. Sylla
  • Moctar Camara
  • Amadou T. Gaye
Original Paper


We analyse the interannual variability of the averaged summer monsoon rainfall over the Sahel from multiple regional climate models driven by the ERA-interim reanalysis and seek to provide effective information for future modelling work. We find that the majority of the models are able to reproduce the rainfall variability with correlation coefficient exceeding 0.5 compared with observations. This is due to a good representation of the dynamics of the main monsoon features of the West African climate such as the monsoon flux, African Easterly Jet (AEJ) and Tropical Easterly Jet (TEJ). Among the models, only HIRHAM fails to reproduce the rainfall variability exhibiting hence a correlation coefficient of −0.2. This deficiency originates from the fact that HIRHAM does not properly capture the variability of monsoon flow and the relationship between rainfall and the AEJ dynamic. We conclude that a good performance of a regional climate model in simulating the monsoon dynamical features variability is of primary importance for a better representation of the interannual variability of rainfall over the Sahel.


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© Springer-Verlag Wien 2012

Authors and Affiliations

  • Ismaila Diallo
    • 1
  • Mouhamadou B. Sylla
    • 2
  • Moctar Camara
    • 3
  • Amadou T. Gaye
    • 1
  1. 1.Laboratory for Atmospheric and Oceanic Physics-Simeon Fongang (LPAO-SF), Polytechnic SchoolCheikh Anta Diop UniversityDakar-FannDakar-Senegal
  2. 2.Department of Civil Engineering and Environmental Science, Seaver College of Science and EngineeringLoyola Marymount UniversityLos AngelesUSA
  3. 3.Department of Physics—UFR of Science and TechnologiesUniversity of ZiguinchorZiguinchorSenegal

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