Variability and Predictability of West African Droughts: A Review on the Role of Sea Surface Temperature Anomalies
Year: 2015
Type: article
Abstract: 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.
Source: Journal of Climate
Authors: Belen Rodríguez-Fonseca, Elsa Mohino, Carlos R. Mechoso, Cyril Caminade, Michela Biasutti, Marco Gaetani, J. Garcia-Serrano, Edward K. Vizy, Kerry Cook, Yongkang Xue, Irene Polo, Teresa Losada, Leonard Druyan, Bernard Fontaine, Juergen Bader, Francisco J. Doblas-Reyes, Lisa Goddard, Serge Janicot, Alberto Arribas, William Lau, Andrew Colman, M. Vellinga, David P. Rowell, Fred Kucharski, Aurore Voldoire
Institutions: Universidad Complutense de Madrid, Consejo Superior de Investigaciones Científicas, Instituto de Geociencias, University of California, Los Angeles, University of Liverpool, Lamont-Doherty Earth Observatory, Columbia University, Istituto di Biometeorologia, National Research Council, Institut Català de Ciències del Clima, The University of Texas at Austin, University of Reading, University of Castilla-La Mancha, Goddard Institute for Space Studies, Centre National de la Recherche Scientifique, Université de Bourgogne, Max Planck Institute for Meteorology, Institució Catalana de Recerca i Estudis Avançats, Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques, Institut de Recherche pour le Développement, Université Pierre-et-Marie-Curie, Met Office, Goddard Space Flight Center, The Abdus Salam International Centre for Theoretical Physics (ICTP), Centre National de Recherches Météorologiques, Météo-France
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: bronze
Awards: Collaborative Research: The Southern Subtropical Anticyclones, Collaborative Research: Use of Climate Information in International Negotiation for Adaptation Resources, Enhancing prediction of tropical Atlantic climate and its impacts, Seasonal-to-decadal climate Prediction for the improvement of European
Climate Services, Sahel Seasonal to Decadal Climate Variability and Atmosphere/Surface Two-Way Interactions, Quantifying Weather and Climate Impacts on Health in Developing Countries, African Monsoon Systems: Basic Dynamics and Applications to Interannual and Decadal Prediction
OpenAlex ID: W2147808072