From large scale to mesoscale dynamics in the Cape Verde Frontal Zone

Abstract

The main goal of this research work, contextualized within Physical Oceanography but also with some multidisciplinary nature, is to complete the ideas that have been established throughout history around the Cape Verde Frontal Zone, CVFZ. Nestled within the highly productive coastal upwelling off Northwest (NW) Africa, the CVFZ is located off the coast of Cape Blanc, in the convergence zone of the Subtropical and Tropical gyres of the North Atlantic where the central waters transported by both gyres, NACW and SACW, form a thermohaline front practically compensated in density and with abundant associated mesoscale structure. Based on in situ measurements carried out during the two cruises of the COCA project and two other cruises of the FLUXES project, the characterization of the CVFZ deepens in order to achieve a better understanding of the physical components that govern its dynamics, from the basin scale, in which the circulation patterns are described north and south of Cape Blanc influenced by the unresolved mesoscale, up to the mesoscale and submesoscale, in which the main thermohaline structures detected above and below 100 m and the associated frontal dynamics are detailed, including the secondary ageostrophic circulation with its respective horizontal and vertical components. In addition, this research work describes the distribution and behavior of the different water masses detected at different levels, as well as, other associated biochemical variables, such as inorganic nutrients, dissolved oxygen and dissolved organic carbon, addressing the uncertainties in the balances of the large-scale biochemical fluxes in the CVFZ.