The Malvinas Current (MC), originated as a branch of the Antarctic Circumpolar Current, flows northward along the 1000-1500 isobaths off the Argentinian coast carrying cold and fresh waters. The Brazil Current (BC) flows southward as the western boundary current of the subtropical gyre, transporting warm and salty waters. Both currents encounter at about 38oS, in what becomes one of the most energetic frontal areas in the ocean. The outcome of this frontal collision is a complex pattern of structures at different scales, from thermohaline intrusions to mesoscale features and regional gyres, which contribute to the exchange properties, such as mass, heat and salt, between both currents and therefore between the ACC and the subtropical gyre. In this study we use inverse-box models to analyze these exchanges at three different scales: frontal, confluence and regional. For the frontal and confluence analyses we use data from a cruise carried out in March 2015, while for the regional analysis we complement it with Argo float profiles. The frontal model encloses the area where the highest temperature and salinity gradients are found, down to approximately 500 meters. The confluence box captures the entrance and outflow of each current in the collision area, while the regional box covers the entire area between 30oS-45oS and the South American coast and 30oW. We divide the water column into vertical layers and impose mass and salt anomaly conservation, within uncertainties, for each layer and the entire upper-water column, allowing for Ekman transport and freshwater exchange in the first layer and dianeutral advection and diffusion between adjacent layers. We find that most of the property transports occur in the surface layers. Nearly all of the water entering the confluence through the southern boundary also leaves the confluence at this boundary. In contrast, most of the water carried by the BC leaves the area through the eastern boundary. At regional scales, we observe that a significant fraction of subantarctic-origin water enters the subtropical gyre, this being the main path for exchange between the subtropical and subantarctic waters

XXXII Trobades Científiques de la Mediterrània, Planeta Oceà - Planet Ocean, celebradas del 5 al 7 de octubre de 2016 en Maó, Menorca.-- Homenatge als Drs. Marta Estrada, Jordi Font i Jordi Salat, pioners de l'oceanografia mediterrània moderna. A tribute to Drs. Marta Estrada, Jordi Font and Jordi Salat, pioneers of modern Mediterranean oceanography.-- 1 page

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