Do submesoscale processes shape the structure of Oxygen Minimum Zones in Eastern Boundary Upwelling Systems?

High resolution model simulations and in-situ observations show the importance of submesoscale processes on the transfer between the upper ocean and the main thermocline. This is mainly a consequence of the associated large vertical velocities that operate on short intervals of time. The integrated impact of these processes on the meso- and larger-scale structures has only recently started to be investigated. In this work, we use a submesoscale-permitting, physical-biogeochemical model simulation to investigate the impact of resolving some submesoscale processes on the formation and evolution of intrathermocline, low-oxygen eddies that are commonly observed in the eastern Tropical Atlantic. Preliminary results show that filamentary, spiraling structures are formed at the edges of intra-thermocline eddies, which induce changes in the shape and evolution of these features in the eastern boundary upwelling system off West Africa, with potential consequences for the overall structure of the oxygen minimum zone.