Hernandez O. auteur aut IRD Jouanno Julien auteur aut IRD Echevin Vincent auteur aut IRD Aumont Olivier auteur aut IRD text journalArticle eng text/pdf born digital access The influence of the chlorophyll on the upper Tropical Atlantic Ocean is investigated with long-term (1979-2012) regional oceanic simulations with 1/48 horizontal resolution based on the NEMO3.6 model. The model solar radiation penetration scheme depends on the chlorophyll concentration. Simulations with time and spatially varying concentrations obtained from satellite ocean color observations are compared with a simulation forced with constant chlorophyll concentration of 0.05 mg m(-3), representative of chlorophyll depleted waters. Results indicate that regions of the Tropical Atlantic with chlorophyll concentrations larger than in the reference simulation (i.e., [chl] > 0.05 mg m(-3)) get warmer at the surface, with the exception of the main upwelling regions where high chlorophyll concentrations are associated with a significant cooling of the sea surface (similar to 1 degrees C in the Benguela upwelling). The analysis of the model heat balance shows that the biological differential heating causes negative temperature anomalies in subsurface source waters prior to their upwelling at the coast. The shallow mixed-layer in the eastern equatorial and tropical Atlantic favors the persistence of these subsurface anomalies and may explain why the Benguela is particularly sensitive to the biological differential heating. In spite of the presence of high chlorophyll concentrations in the upwelling regions, both the larger amount of shortwave radiation captured in the surface layers and the modifications of the horizontal and vertical advection at the coast are found to play a secondary role in the SST change in the upwelling region. specialized ATLANTIQUE MAURITANIE SENEGAL ZONE TROPICALE 036 032 020 126 122 7 5367-5389 2017 2169-9275 https://www.documentation.ird.fr/hor/fdi:010070999 10.1002/2016jc012330 2169-9275 [F B010070999] https://www.documentation.ird.fr/hor/fdi:010070999 https://www.documentation.ird.fr/intranet/publi/2017/09/010070999.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2017-10-03 2023-07-11 fdi:010070999 fre