Existe limitada e esparsa informação na literatura sobre a Corrente do Brasil, a corrente de contorno que fecha o Giro Subtropical do Atlântico Sul em sua borda oeste. Neste artigo, compilamos as informações atualmente disponíveis na literatura para fornecer uma visão dos aspectos cinemáticos e dinâmicos desta corrente, enquanto flui ao largo do Leste Brasileiro. Discutimos sua composição em termos de massas de água e de sua extensão vertical em diversas latitudes. Também apresentamos levantamento atualizado sobre aspectos cinemáticos desta corrente, tanto em termos de velocidades observadas e geostróficas como de transportes de volume. Informações sobre o meandramento e formação de vórtices na Corrente do Brasil, ao largo da costa Sudeste, e seu provável papel na penetração da Água Central do Atlântico Sul. na quebra da plataforma continental, igualmente são abordados.
A hydrographic survey on board the German ship FS Victor Hensen was carried out in Brazilian coastal waters between Santos (23°56'S) and Rio de Janeiro (22°54'S) from January 15 to January 22, 1991. Analyses of conductivity‐temperature‐depth (CTD) data collected during this cruise show that the geostrophic flow and water mass structure of the Brazil Current in that region have characteristics similar overall to those in the better observed Cabo Frio region. The uppermost 200 m of the water column is dominated by the warm, highly saline Tropical Water flowing predominantly to the southwest. This flow direction appears to persist to approximately 900 m, the maximum depth reached by the CTD casts. The water lying between 250 and 750 m has the characteristics of South Atlantic Central Water (SACW). Below 750 m, down to 900 m, the water characteristics are those of Antarctic Intermediate Water. The thermohaline structure and geostrophic calculations indicate the presence of a meandering pattern, with a trough that appears to be the early stage of formation of a cold‐core eddy over the upper slope region. This feature extends from the surface down to approximately 500 m depth and is apparently associated with the intrusion of SACW onto the continental shelf. The geostrophic computations (with respect to two reference levels, 750 and 900 dbar) yield maximum current values in the range 0.6–0.7 m s−1. The southwestward volume transport, averaged over the entire domain, was approximately 7.3 Sv with respect to 750 dbar and 8.8 Sv with respect to 900 dbar.
There is relatively few and sparse information in the literature about the Brazil Current, the boundary current that closes the westem border of the South Atlantic Subtropical Gyre. ln this article, we present a review of the currently-available literature to give a coherent overview on the kinematic and dynamical aspects of the Brazil Current along the Eastem Brazilian eoast. We discuss the current structure in terms of its water mass composition and its vertical extension. We compile the available information on the Brazil Current velocity structure and volume transport along the shelf and shelf break from 90S to 3loS. We also address the Brazil Current meandering and eddy formation, and their possible role in promoting shelf-break upwelling off the Southeast Brazilian coast.
Abstract---Geostrophic volume transports in the upper 500 m are computed from historical hydrographic data for the area off the Brazilian coast west of 30*W and between 7 ° and 20"S. On the basis of water mass distributions, potential density surfaces of o0 = 27.05 kg m -3 (360-670 m) and o8 = 27.6 kg m -3 (-1200 m) are used for referencing the meridional and zonal components of the geostrophic shears, respectively. Near 15"S a northwestward flow of 8 Sv crosses 30*W. This current reaches the shelf near 10"S in February and March, the only two months for which observations are available near that latitude along the coast; of the 8 Sv, about 4 Sv continue towards the northwest into the North Brazil Current while another branch also carrying 4 Sv turns southward as the beginning of the Brazil Current. Between 10 ° and 20~S the Brazil Current does not appear to strengthen appreciably, but because of the likely existence of flow on the shelf these transport values represent lower limits to the actual ones. At 30°W, another westward flow of approximately 8-10 Sv enters the area near 10°S and serves to strengthen the North Brazil Current. The total transfer of 12 Sv or more from the South Equatorial Current into the North Brazil Current and later to other currents and the northern hemisphere may be an important factor contributing to the well-known weakness of the Brazil Current in its more northerly latitudes.
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