Rodriguez-Fonseca, B; Mohino, E; Mechoso, CR; Caminade, C; Biasutti, M; Gaetani, M; Garcia-Serrano, J; Vizy, EK; Cook, K; Xue, YK; Polo, I; Losada, T; Druyan, L; Fontaine, B; Bader, J; Doblas-Reyes, FJ; Goddard, L; Janicot, S; Arribas, A; Lau, W; Colman,

[Rodriguez-Fonseca, Belen; Mohino, Elsa] Univ Complutense Madrid, Fac Ciencias Fis, Dept Fis Tierra Astron & Astrofis 1, E-28040 Madrid, Spain; [Rodriguez-Fonseca, Belen] CSIC, Inst Geociencias, Madrid, Spain; [Rodriguez-Fonseca, Belen] Univ Complutense Madrid, E-28040 Madrid, Spain; [Mechoso, Carlos R.; Xue, Yongkang] Univ Calif Los Angeles, Dept Atmospher & Ocean Sci, Los Angeles, CA USA; [Caminade, Cyril] Univ Liverpool, Inst Infect & Global Hlth, Sch Environm Sci, Liverpool L69 3BX, Merseyside, England; [Biasutti, Michela] Columbia Univ, Lamont Doherty Earth Observ, New York, NY USA; [Gaetani, Marco] CNR, Ist Biometeorol, Rome, Italy; [Garcia-Serrano, J.; Doblas-Reyes, Francisco J.] Inst Catala Ciencies Clima, Barcelona, Spain; [Vizy, Edward K.; Cook, Kerry] Univ Texas Austin, Jackson Sch Geosci, Dept Geol Sci, Austin, TX USA; [Polo, Irene] Univ Reading, Dept Meteorol, NCAS Climate, Reading, Berks, England; [Losada, Teresa] Univ Castilla La Mancha, Inst Ciencias Ambientales, Toledo, Spain; [Druyan, Leonard] Columbia Univ, Ctr Climate Syst Res, New York, NY USA; [Druyan, Leonard] NASA, Goddard Inst Space Studies, New York, NY 10025 USA; [Fontaine, Bernard] Univ Bourgogne, CNRS, Ctr Rech Climatol, Dijon, France; [Bader, Juergen] Max Planck Inst Meteorol, D-20146 Hamburg, Germany; [Doblas-Reyes, Francisco J.] Inst Catalana Recerca & Estudis Avancats, Barcelona, Spain; [Goddard, Lisa] Columbia Univ, Int Res Inst Climate & Soc, New York, NY USA; [Janicot, Serge] UPMC, LOCEAN IPSL, IRD, Paris, France; [Arribas, Alberto; Colman, Andrew; Vellinga, M.; Rowell, David P.] Met Off Hadley Ctr, Exeter, Devon, England; [Lau, William] NASA, Goddard Space Flight Ctr, Atmospheres Lab, Greenbelt, MD 20771 USA; [Kucharski, Fred] Abdus Salam Int Ctr Theoret Phys, Trieste, Italy; [Voldoire, Aurore] CNRS, Meteo France, Grp Etud Atmosphere Meteorol, Ctr Natl Rech Meteorol, Toulouse, France

The Sahel experienced a severe drought during the 1970s and 1980s after wet periods in the 1950s and 1960s. Although rainfall partially recovered since the 1990s, the drought had devastating impacts on society. Most studies agree that this dry period resulted primarily from remote effects of sea surface temperature (SST) anomalies amplified by local land surface-atmosphere interactions. This paper reviews advances made during the last decade to better understand the impact of global SST variability on West African rainfall at interannual to decadal time scales. At interannual time scales, a warming of the equatorial Atlantic and Pacific/Indian Oceans results in rainfall reduction over the Sahel, and positive SST anomalies over the Mediterranean Sea tend to be associated with increased rainfall. At decadal time scales, warming over the tropics leads to drought over the Sahel, whereas warming over the North Atlantic promotes increased rainfall. Prediction systems have evolved from seasonal to decadal forecasting. The agreement among future projections has improved from CMIP3 to CMIP5, with a general tendency for slightly wetter conditions over the central part of the Sahel, drier conditions over the western part, and a delay in the monsoon onset. The role of the Indian Ocean, the stationarity of teleconnections, the determination of the leader ocean basin in driving decadal variability, the anthropogenic role, the reduction of the model rainfall spread, and the improvement of some model components are among the most important remaining questions that continue to be the focus of current international projects.