Weakening of the Senegalo–Mauritanian upwelling system under climate change

  • Adama SyllaEmail author
  • Juliette Mignot
  • Xavier Capet
  • Amadou Thierno Gaye


Upwelling processes bring nutrient-rich waters from the deep ocean to the surface. Areas of upwelling are often associated with high productivity, offering great economic value in terms of fisheries. The sensitivity of spring/summer-time coastal upwelling systems to climate change has recently received a lot of attention. Several studies have suggested that their intensity may increase in the future while other authors have shown decreasing intensity in their equatorward portions. Yet, recent observations do not show robust evidence of this intensification. The Senegalo-Mauritanian upwelling system (SMUS) located at the southern edge of the north Atlantic system (12°N–20°N) and most active in winter/spring has been largely excluded from these studies. Here, the seasonal cycle of the SMUS and its response to climate change is investigated in the database of the Coupled Models Inter comparison Project Phase 5 (CMIP5). Upwelling magnitude and surface signature are characterized by several sea surface temperature and wind stress indices. We highlight the ability of the climate models to reproduce the system, as well as their biases. The simulations suggest that the intensity of the SMUS winter/spring upwelling will moderately decrease in the future, primarily because of a reduction of the wind forcing linked to a northward shift of Azores anticyclone and a more regional modulation of the low pressures found over Northwest Africa. The implications of such an upwelling reduction on the ecosystems and local communities exploiting them remains very uncertain.


Upwelling Climate change Climate models Northeastern tropical Atlantic 



A. Sylla was supported for this study by a scholarship from IRD (Institut de Recherche pour le Développement), from the French Embassy in Senegal and from AMMA 2050 innovative fund (SCUS-2050 project Grant Number M0220428/1). The authors also acknowledge support from the Laboratoire Mixte International ECLAIRS2. This study benefited from the ESPRI computing and data center ( which is supported by CNRS, Sorbonne Université, Ecole Polytechnique and CNES and through the ANR (Grant #ANR-10-LABX-0018) and the European FP7 IS-ENES2 project (Grant #312979).


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Adama Sylla
    • 1
    • 2
    Email author
  • Juliette Mignot
    • 2
  • Xavier Capet
    • 2
  • Amadou Thierno Gaye
    • 1
  1. 1.Laboratoire de Physique de l’Atmosphére et de l’Ocean Simeon Fongang (LPAO-SF/ESP/UCAD)DakarSénégal
  2. 2.Sorbonne Universités (CNRS/IRD/MNHN), LOCEAN LaboratoryParisFrance

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