Physical and Biological Satellite Observations of the Northwest African Upwelling: Spatial Extent and Dynamics

Anass El Aouni (1) , Véronique Garçon (2) , Joël Sudre (2) , Hussein Yahia (1) , Khalid Daoudi (1) , Khalid Minaoui (3)

1 GeoStat - Geometry and Statistics in acquisition data
2 LEGOS - Laboratoire d'études en Géophysique et océanographie spatiales
3 LRIT - Laboratoire de Recherche Informatique et Télécommunications

The region along the NorthWest African coast (20 • N to 36 • N and 4 • W to 19 • W) is characterized by a persistent and variable upwelling phenomenon almost all year round. In this article, the upwelling features are investigated using an algorithm dedicated to delimit the upwelling area from thermal and biological satellite observations. This method has been developed specifically for sea-surface temperature (SST) images, since they present a high latitudinal variation, which is not present in chlorophyll-a concentration images. Developing on the proposed approach, the spatial and temporal variations of the main physical and biological upwelling patterns are studied. Moreover, a study on the upwelling dynamics, which explores the interplay between the upwelling spatiotemporal extents and intensity, is presented, based on a 14-year time archive of weekly SST and chlorophyll-a concentration data.

Mots clés: Canary current system; Chlorophyll-a; Clustering; Sea-surface temperature (SST); Upwelling; Seasonal variability

Domaines: Dynamique Chaotique [nlin.CD]; Physique mathématique [math-ph]; Systèmes dynamiques [math.DS]; Mécanique des fluides [physics.class-ph]

Anass El Aouni, Véronique Garçon, Joël Sudre, Hussein Yahia, Khalid Daoudi, et al.. Physical and Biological Satellite Observations of the Northwest African Upwelling: Spatial Extent and Dynamics. IEEE Transactions on Geoscience and Remote Sensing, 2019, pp.1-13. ⟨10.1109/TGRS.2019.2946300⟩. ⟨hal-02355252⟩