Skip to Main content Skip to Navigation
Journal articles

Causes of the Northern Gulf of Guinea Cold Event in 2012

Abstract : Particularly cool sea surface temperatures (SSTs) were observed in 2012 along the Northern Gulf of Guinea coast. This strong cooling event was seen from February to June and reached maxima in the coastal upwelling areas: SST anomalies of −1°C were observed in Sassandra Upwelling area in Côte d'Ivoire (SUC, situated east of Cape Palmas) and SST anomalies of −0.5°C were observed in Takoradi Upwelling area in Ghana (TUG, located east of Cape Three Points). In SUC and TUG regions, the 2012 decrease in SST was the coldest event recorded over the 1990-2018 period (29 years). From the analysis of regional simulations, we show that the mechanisms behind this SST decrease differ in the two regions. In the SUC region, we identify changes in both zonal advection (related to zonal SST gradient changes) and increased vertical mixing as the main drivers of the anomalous cooling. The anomalous vertical mixing is linked to increased vertical shear of the zonal current in response to the Guinea Current strengthening. In the TUG region, acceleration of the southward advection of the surface water, due to the intensification of the meridional Ekman current generated by the strengthening of the zonal wind stress, was identified as the major cause of the SST anomalous cooling.
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03671328
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Wednesday, May 18, 2022 - 2:37:55 PM
Last modification on : Wednesday, June 1, 2022 - 4:12:09 AM

File

JGR Oceans - 2021 - Da%u2010Al...
Publisher files allowed on an open archive

Licence

Copyright

Identifiers

Collections

Citation

C. y. Da-Allada, J. Agada, E. Baloïtcha, M. N. Hounkonnou, J. Jouanno, et al.. Causes of the Northern Gulf of Guinea Cold Event in 2012. Journal of Geophysical Research: Oceans, 2021, 126, ⟨10.1029/2021JC017627⟩. ⟨insu-03671328⟩

Share

Metrics

Record views

16

Files downloads

0