Seasonal and inter-annual ONSET Sea Surface Temperature variability along the northern coast of the Gulf of Guinea

Type Article
Date 2020-03
Language English
Author(s) Sohou Z.1, 2, Koné V.3, Da-Allada Y.C.1, 4, 5, Djakouré S.6, Bourlès Bernard7, Racape Virginie8, Degbe G.1, Adje C.1
Affiliation(s) 1 : Institut de Recherches Halieutiques et Océanologiques du Bénin (IRHOB/CBRSI), Benin
2 : Département Zoologie, Faculté des Sciences et Techniques (FAST/UAC), Benin
3 : Centre de Recherches Océanologiques de Côte-d’Ivoire (CRO), 29, Rue des Pêcheurs, BPV 18, Abidjan, Cote d’Ivoire
4 : ENSTP/UNSTIM, Abomey, Benin
5 : ICPMA-UNESCO Chair/UAC, Cotonou, Benin
6 : Laboratoire de Physique de l’Atmosphère et de Mécanique des Fluides (LAPA-MF), UFR SSMT, Université Félix Houphouët-Boigny, Abidjan, Cote d’Ivoire
7 : IRD/IMAGO, Centre IRD de Bretagne, Technopole Pointe du Diable, Plouzané, France
8 : CNRS/CORIOLIS, Plouzané, France
Source Regional Studies In Marine Science (2352-4855) (Elsevier BV), 2020-03 , Vol. 35 , P. 101129 (11p.)
DOI 10.1016/j.rsma.2020.101129
WOS© Times Cited 11
Keyword(s) Sea Surface Temperature, ONSET data, Gulf of Guinea, Coastal upwelling, Seasonal variability, Inter-annual variability
Abstract

The aim of this study is to characterize the coastal upwelling variability at seasonal and inter-annual time scales in the northern Gulf of Guinea (NGoG) using Sea Surface Temperature (SST) collected with autonomous “ONSET” thermometers. Results show that the ONSET SST data are suitable for numerical model evaluation, and provide relevant information in addition to satellite and reanalysis data at seasonal cycle. The minor and major coastal upwellings are present in all the products. The inter-annual SST variability is more pronounced in the western part of the region (Côte d’Ivoire and Ghana) than in the eastern part (Benin and Nigeria). The pattern differences between the west and the east of the region highlight a large spatial variability of the SST in the NGoG. Indeed, the signal of the minor upwelling season is visible only in the west of the basin, namely between Cape Palmas and Cape Three Points. We also observe a well-established thermal gradient between the western and eastern parts of the basin. This gradient is increasing from west to east during the major upwelling season, and decreasing from east to west during the rest of the year. The coastal ONSET data allow to evidence higher SST anomalies than those deduced from satellite and reanalysis products. Although the cold or warm events observed in 2008, 2010 and 2012 are well detected by all products, only the ONSET data set reveal the strong negative SST anomaly observed in 2009 along the coast of Ghana and Côte d’Ivoire.

Full Text
File Pages Size Access
Author's final draft 30 2 MB Open access
11 3 MB Access on demand
Top of the page

How to cite 

Sohou Z., Koné V., Da-Allada Y.C., Djakouré S., Bourlès Bernard, Racape Virginie, Degbe G., Adje C. (2020). Seasonal and inter-annual ONSET Sea Surface Temperature variability along the northern coast of the Gulf of Guinea. Regional Studies In Marine Science, 35, 101129 (11p.). Publisher's official version : https://doi.org/10.1016/j.rsma.2020.101129 , Open Access version : https://archimer.ifremer.fr/doc/00607/71885/