The shelf and coastal waters off southern Brazil

Abstract

The data collected on three oceanographic cruises undertaken in 1956 indicate that the main branch of the Brazil Current flows southwards along the continental slope, where it reaches maximum velocity, and further, that a well defined limit is found between the warm and saline tropical water from the north and that situated over the central part of the shelf. This is especially the case during the summer months (October-March). Below the Brazil Current a water layer of lower salinity and temperature is found. This water mass is formed near the western extremity of the Subtropical Convergence where it sinks and flows northwards to reappear near or at the surface in an area situated between the lighter, south-flowing, tropical water, and the coastal water. Such a distribution of density across the Current is to be expected in view of the dynamics of ocean currents. There are, however, evidences which indicate the occurrence of upwelling from moderate depths, in particular near Cabo Frio where the prevailing winds from NE drive the surface waters offshore. It is further suggested that the upwelling is maintained by a thermohaline mechanism as the density of the cold and low salinity water is decreased by heating from solar radiation. In order to maintain dynamic stability, the heated water must consequently flow out of the area and be replaced by water from below which in turn suffers the same decrease of density, and so on. Such mechanism might, together with prevailing winds, be responsible for permanent or periodic upwelling near other regions in the tropical and subtropical zone of the oceans where salinity decreases with depth.

Oceanographic characteristics of Baía de Todos os Santos, Brazil

“…The waters on the inner shelf had surface salinity above 37. According to Emilson (1961), the water mass in the BTS (and along the associated shelf) during the summer could be classified as Tropical Water -TW (temperatures above 20 • C and salinities above 36). Table 7 -Mean temperature and salinity and ± 1 standard deviation for the stations where water properties were collected during a complete tidal cycle (neap situation) for the summer sampling period.…”

Comunidades microplanctônicas no Oceano Atlântico Sul Ocidental: biomassa e distribuição em novembro de 1992

“…(1942), Emílsson (1961), Boltovskoy (1981), Matsuura (1986), Peterson & Stramma (1991) e Stramma & England (1999), cinco domínios hidrográficos de superficie podem ser reconhecidos no transecto latitudinal amostrado ao longo do OASO.…”

Long-term variation in the ichthyofauna of Flamengo Cove, Ubatuba, São Paulo

“…Local temperature ranges from 14.6°C to 27.9°C and the salinity stands around 31.7 to 35.8 (Cunningham, 1983;Mahiques, 1995). In general, the cove is under the seasonal influence of cold, deep and salty subtropical waters (Emílsson, 1961). More specifically, the Flamengo Cove is under seasonal influence of the warmer Coastal Water (CW) and the South Atlantic Central Water (SACW) with colder and salty waters (Cunningham, 1983;Castro Filho et al, 1987).…”