RT journal article
T1 Modelling the effect of the tidal cycle on the high phytoplankton biomass area of Cape Trafalgar (SW Iberian Peninsula)
A1 Sala Martínez, Iria
A1 Vallina, Sergio M.
A1 Lévy, Marina
A1 Bolado Penagos, Marina
A1 García Jiménez, Carlos Manuel
A1 Echevarría Navas, Fidel María
A1 Sánchez-Garrido, José Carlos
A2 Biología
A2 Física Aplicada
K1 Tidal mixing
K1 Physical–biological coupled model
K1 Phytoplankton
K1 Cape Trafalgar
K1 Strait of Gibraltar
AB Physical–biological interactions in the ocean are known to be crucial for understanding ecosystem processes. This is particularly relevant in the highly dynamic coastal regions, where the biogeochemical processes associated with higher-frequency perturbations such as tidal waves play a key role in primary production. In this study, we examine the influence of the tide-topography interaction on the high productivity area of Cape Trafalgar (NW limit of the Strait of Gibraltar, Iberian Peninsula) using a high-resolution ocean circulation model coupled to an ecosystem model. The obtained results highlight the relevance of the tidal cycle explaining the high phytoplankton biomass that characterises this region through an active and periodic forcing, resulting in a pulsating upwelling system. Our model shows that the interaction of the westward zonal component of the tidal current (uvel) with the submarine ridge (i.e., Barbate High) that characterises this region, which is perpendicular to the coast, results in the pumping of deep, cold, salty, and nutrient-rich waters to the well-illuminated subsurface waters, fuelling phytoplankton growth. At the same time, the interaction of the westward tidal current with the ridge leads to the development of a cyclonic eddy, which enables the redistribution of the upwelled waters over and to the east of Barbate High. The fortnightly tidal period has been identified as the most influential because (an effective) tidal-pumping process only takes place when the westward uvel is ∼ 0.42 m s−1, a condition attained between ∼ 3 days before and after the moment of maximum tidal flow during spring tides. Simultaneously, the energy and the associated horizontal and vertical mixing of the cyclonic gyre also vary with the tidal cycle, being stronger during spring tides. Both tidally driven processes, i.e., the cyclical upslope advection of deep nutrient-rich water and the influence of the cyclonic gyre, are the main mechanisms that lead to the development of a persistent phytoplankton-rich tongue over Barbate High. Consequently, Cape Trafalgar acts as a source of nutrient- and phytoplankton-rich waters to the surrounding waters.
PB Elsevier
SN 0079-6611
YR 2023
FD 2023
LK http://hdl.handle.net/10498/32503
UL http://hdl.handle.net/10498/32503
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 09-nov-2026