Dynamics of the Brazil-Malvinas Confluence: Energy Conversions

Energetics of eddy‐mean flow interactions in the Brazil current between 20°S and 36°S

“…In this study, the density is assumed to be a function of the temperature in the form . Thus, the potential energy is also defined as a function of the temperature field [e.g., Bryden , ; Rossby , ; Cronin and Watts , ; Francisco et al ., ]. In subtropical regions, such as the focus of this study, a strong dependence between density and temperature fields is known to exist [e.g., Talley et al ., ].…”

“…The BC has not been characterized in energy terms. Studies have summarized general estimates from drifting buoys [ Piola et al ., ; Assireu et al ., ; Oliveira et al ., ] or numerical modeling [ Mano et al ., ; Francisco et al ., ]. Piola et al .…”

“…Francisco et al . [] investigated the energy conversion in the region of the Brazil‐Malvinas Confluence using the Hybrid Coordinate Ocean Model (HYCOM) and observed the dominance of the baroclinic conversion over the barotropic conversion. Rocha et al .…”

On the dynamics of the Brazil Current site of origin

“…That translates in a very small Rossby Number. To test this we evaluate the mean Rossby Number for each of the jets during the CONTROL run, following the steps of Francisco et al [2011]. Following these authors we've chosen to compute the Rossby number in the form of the ratio between relative and planetary vorticity,…”

“…This is a necessary condition, but it does not automatically guarantees the occurrence of instability. In order to verify if there is a baroclinic instability process occurring in the BC domain, we perform energy conversion calculations with the method used by Cronin & Watts [1996], and already applied by Francisco et al [2011] and Mano et al [2009] to different regions of the Brazilian coast.…”