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.

There is relatively few and sparse information in the literature about the Brazil Current, the boundary current that cJoses the western border of the South Atlantic Subtropical Gyre. In this articJe, 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 Eastern Brazilian coast. 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 31°S. We also address the Brazil Current meandering and eddy formation, and their possible role in promoting shelf-break upwelling off the Southeast Brazilian coast.

Como parte do projeto MAR-14, componente do Acordo Bilateral Brasil-Alemanha em Ciências Marinhas, uma campanha oceanógrafica a bordo do R/V Victor Hensen foi realizada em águas costeiras do Brasil entre Santos (23º56'S), de 15 a 22 de janeiro de 991. Neste artigo reportamos resultados de análises preliminares dos dados hidrográficos coletados com o auxílio de CTD, STD, garrafas de Nansen e XBT's. Esses resultados preliminares mostram uma intensa estratificação nos primeiros 200 m de profundidade, e a penetração da corrente bem adentro da região sobre a plataforma continental. Duas estruturas com características de vórtices de meso-escala foram detectadas. O primeiro, anticiclônico, estava localizado na parte norte da rede de estações e confinado praticamente nos primeiros 200 m de profundidade. O Segundo, um vórtice ciclónico, foi encontrado um pouco para o sudoeste e abaixo dos 200 m, estendendo-se para baixo até cerca de 800 metros. Análises de Massa de água baseadas em diagramas T-S sugerem que a interface entre a Água Central do Atlântico Sul (ACAS) e a Água Intermediária Antártica (AIA) se encontrava em aproximadamente 500 m de profundidade. Um aspecto importante desse cruzeiro que deve ser ressaltado é que, esta foi a primeira vez em que um sensor do tipo CTD foi utilizado com essa resolução ao longo da costa leste do Brasil, abaixo de Cabo Frio.

Within the scope of the MAR-14 Project, part of the Brazil-Germany Bilateral Agreement in Marine Sciences, an oceanographic survey aboard the R/V Victor Hensen was carried out in Brazilian coastal waters between Santos (23º56'S) and Rio de Janeiro (22º54'S), from January 15 to January 22,1991. In this article we report results of preliminary analyses of the hydrographic data collected with CTD, STD, Nansen bottles and XBT's. These preliminary results show intense stratification in the first 200 m depth, and the penetration of the Brazil Current deep into the continental shelf region. Two eddy-like features were detected. The first one, anticyclonic, was located in the northern part of the domain and confined to the uppermost 200 m. The second, a cyclonic vortex, was found a little to the southwest below 200 m and extending downwards to about 800 m depth. Water mass analyses based on T-S diagrams suggest that the interface between the South Atlantic Central Water (SACW) and the Antarctic Intermediate Water (AIW) is located at about 500 m depth. One important aspect of this study is that this was the first time a high resolution survey with a CTD probe was realized along the eastern Brasilian Coast, south of Cabo Frio.

The objective of this work is to study the possibility of estimating the heat flux balance at the sea surface from GOSSTCOMP (Global Ocean Sea Surface Temperature Computation) developed by NOAA/NESS, USA, and sea surface current data based from ships drift information obtained from Pilot Charts, published by the Diretoria de Hidrografia e Navegação (DHN, Brazilian Navy). The annual mean value of the heat flux balance at the sea surface off southeast Brazil for 1977, is estimated from data on the balance between the heat transported by the currents and that transported by eddy diffusion for each volume defined as 2º x 2º (Lat. x Long.) square with a constant depth equivalent to an oceanic mixed layer, 100 m thick. Results show several oceanic areas where there are net flows of heat from atmosphere towards the sea surface. In front of Rio de Janeiro the heat flow was downward and up to 70 ly day-1 and is probably related to the upwellirug phenomenon normally occurring in that area. Another coastal area between Lat. 25ºS to 28ºS indicated an downward flow up to 50 ly day-1; and for an area south of Lat. 27ºS, Long. 040ºW - 048ºW an downward flow up to 200 ly day-1, where the transfer was probably due to the cold water of a nortward flux from the Falkland (Malvinas) Current. Results also show several oceanic areas where net flows of heat (of about -100 ly day-1) were toward the atmosphere. In the oceanic areas Lat. 19ºS - 23ºS and Lat. 24ºS - 30ºS, the flows were probably due to the warm water of a southward flux of the Brazil Current. The resulting fluxes from the warm waters of the Brazil Current when compared with those from warm waters of the Gulf Stream and Kuroshio, indicate that the Gulf Stream carries about 3.3 times and the Kuroshio 1.7 times more heat than the Brazil Current. These values agree with those of data available on the heat fluxes of the above mentioned Currents calculated by different methods (Budyko, 1974).

Seasonal differences in sigma-t (1.8)3 temperature (4.0ºC) and salinity (0.9‰) were observed during February/June 1976 in the vicinity of Ilha Grande off the coast of Brazil Estimates of static and dynamic stability were made through the calculation of Brunt-Vaisala frequencies and Richardson numbers, respectively. Both static and dynamic stability values were larger in February than in June for the same location and suggest a greater column stability in February than in June. Stations located in the northern and western channels of Ilha Grande, however, contained greater density reversals than to the east of the Island. Small scale dispersion studies were made using Rhomamine B dye to determine horizontal diffusion coefficients (K) east of the Island and in an embayment of the Island. The estimate for K was 9X10³ cm² s-1 east of the Island, about 2.6 times greater than the value estimated for the protected embayment.

A utilização de sensores remotos em oceanografia tem sido amplamente aumentada principalmente devido aos aspectos sinópticos, ao aumento da precisão das informações bem como do aspecto econômico. Este trabalho apresenta as características e os resultados primários de alguns vôos executados sobre o mar na região próxima a Santos e Ilha de São Sebastião, na costa sudeste do Brasil. A técnica mostrou-se eficiente na verificação dos processos de circulação costeira, bem como em qualquer processo em que se utilize a temperatura como traçador. As correntes de maré parecem exercer grande influência na área próxima a baía de Santos, onde uma velocidade superficial média da ordem de 1,2 m/s foi estimada, e essa influência pode se estender à distância da ordem de 50 mn. Podemos observar também a possível divisão da área, pelo menos superficialmente, em duas sub-áreas, com comportamentos térmicos diferentes, cuja interface se desenvolve normalmente à costa em frente a Santos.

The use of remote sensing in oceanography, has been largely increased, mainly because the synoptic look, the accuracy of the data as well as the economics aspects. This paper shows the features and the first results of some experiments performed in the offshore region near Santos Bay and São Sebastião Island, in the southeast coast of Brazil. The technique seems to be powerfull in coastal circulation studies, as well as, in every process that uses the temperature as a natural tracer. The tide currents seem to have large influence in the area near the Santos Bay, with a surface mean speed of about 1.2 m/s, which can reach distances of about 50 n.m. One can note that the area can be divided, at least in surface terms, in two subareas, with different thermal behaviours, with the interface standing normal to the coast in front of Santos.

A mesosoale study was made of the Ilha Grande area. The local circulation described through -progressive vector diagrams showed a clochwise bottom circulation determined in June 1976, while in the upper 10 m the direction of the flow entering the Ilha Grande Bay was towards the center in the west and towards the Marambaia sandbank in the east side of the Bay. Short periods and amplitude fluctuations were evaluted using power spectral analysis, Fourier and Maximum Entropy Method, which showed that in the upper 10 m predominant periods decrease from 1.1h (A = 6.3cm sec-1) (position = 3C) to 1.0h (A = 7.4 cm sec-1) (position = 2D) and increase to 5.8h (A = 6.8 cm., sec-1) (position = ID), while at the bottom layer the predominant period increases from 0.4 h (A = 5.0 cm sec-1) (position = 3G) to 6.4h (A = 7.0 cm sec-1) (position = 2G) and to 4.4h (A = 7.9 cm sec-1) (position = 1G) . From the original data it has been possible to determine an "intense pulsation" between 30-70 cm sec-1 in the upper 10 m with about 1.0h period and 10-20 min duration in all the stations.

Registros contínuos da temperatura e da salinidade, em função de distâncias horizontais, foram obtidos para as águas de superfície existentes ao redor da Ilha Grande, em 21 de junho de 1975. Foi detectado um fluxo de água com baixa salinidade (S ~ 33,10º /oo) e temperatura ligeiramente maior do que a das águas adjacentes, na região entre a Ponta de Castelhanos e a Ponta Grossa da Marambáia. A interação entre este fluxo e as águas costeiras mais salinas (S ~ 35,4 a 35,6º /oo) se apresentou de forma visível, como uma frente salina. Os valores de salinidade, registrados à leste da Ilha Grande sugerem, que a origem dessa agua de baixa salinidade ê a descarga fluvial na Baía de Sepetiba.

Continuous records of temperature and salinity were obtained on the surface waters as function of the horizontal distances around Ilha Grande region, on June 21, 1975; an outflow of less saline (S~33.10º /oo ) and slightly warmer water was detected throughout the region between Ponta de Castelhanos and Ponta Grossa da Marambaia and a visible manifestation of a saline front was observed in the interaction of this outflow with the coastal and more saline water (S~ 35.4 to 35.6º /oo). The recorded salinity values in the east region of Ilha Grande, suggest that the source of less saline water is the runoff in the Baia de Sepetiba.

Um aspecto importante a ser apontado no presente trabalho ê o fato de se ter acompanhado de um modo ininterrupto, durante 10 dias, as anomalias nas distribuições das propriedades físicas da água do mar. Os resultados experimentais obtidos na região costeira a oeste de Cabo Frio durante esse pe ríodo mostraram a preponderância dos processos advectivos e difusivos que alteram a distribuição da temperatura e da salinidade na superfície do mar. Essa anomalia pode ser indicada por nuvens do tipo cúmulos formada por convecção penetrante, fato verificável pela comparação dos dados térmicos de superfície, com fotografias obtidas pelo satélite ERTS.

It should be pointed out that this paper reports observations conducted ininterruptdly during a 10 day period on anomalous distribution of physical properties of sea water. The experimental results obtained on the coastal region west off Cabo Frio (RJ), during the mentioned period showed the dominance of advectives and difusal processes causing changes in the distribution of temperature and salinity on sea surface layer. The anomaly recorded may be indicated by clouds of the "cumulus" type formed by penetrating convection, a fact which may be confirmed by comparing photographic data obtained by ERTS satellite.