Mean sea-level rise impacts on Santos Bay, Southeastern Brazil – physical modelling study

Abstract

The greenhouse effect and resulting increase in the Earth's temperature may accelerate the mean sea-level rise. The natural response of bays and estuaries to this rise, such as this case study of Santos Bay (Brazil), will include change in shoreline position, land flooding and wetlands impacts. The main impacts of this scenario were studied in a physical model built in the Coastal and Harbour Division of Hydraulic Laboratory, University of São Paulo, and the main conclusions are presented in this paper. The model reproduces near 1,000 km(2) of the study area, including Santos, São Vicente, Praia Grande, Cubatão, Guarujá and Bertioga cities.

Variação temporal do microfitoplâncton no Canal Estuarino de Santos (SP)

“…O transporte de material particulado é parcialmente dirigido pelos fluxos dos canais estuarinos de Santos e São Vicente. De acordo com Alfredini et al (2008), em escalas temporais menores, como a do presente estudo, a ressuspensão do sedimento depositado também pode ser uma fonte importante de séston em marés de sizígia ou quando a mistura turbulenta é gerada por ventos mais fortes. Em marés de sizígia, ou em períodos de máxima velocidade da corrente de maré, o aumento da mistura turbulenta causa a ressuspensão de sedimentos de fundo, ricos em material inorgânico, enquanto que a diminuição dessa turbulência, dado ao aumento da estratificação halina, aumenta a contribuição de matéria orgânica, de origem fluvial (Ciotti, A. M.-comunicação pessoal), situação observada na campanha de Abril/2006.…”

Changes in phytoplankton composition in response to tides, wind-induced mixing conditions, and freshwater outflows in an urbanised estuarine complex

“…Precipitation rates are significantly higher in the summer, and wind velocities are higher during winter (Harari et al, 2008). Tides are semi-diurnal and are of less than a metre in amplitude, but together with remote (mesoscale) winds, control the dynamics of local water masses and vertical mixing (Alfredini et al, 2008).…”

Variability in the light absorption coefficients of phytoplankton, non-algal particles, and colored dissolved organic matter in a subtropical bay (Brazil)

“…Our sampling was conducted in the Santos Estuary Channel and Santos Bay, a semi-enclosed area approximately 7.0 km long and 7.3 km wide at its widest point, with an average depth of 15 m (DHN, 2003). Tides are semi-diurnal with less than a meter in amplitude, but in association with mesoscale winds influences the dynamics of local water masses, and vertical mixing (Alfredini et al, 2008). Because of its shallow bathymetry and significant tidal mixing (Harari and Camargo, 2003), the plume formed in the bay is a mixture of intermittent continental sources and oceanic water masses.…”

“…The resuspension of bottom sediments can occur episodically during strong tidal currents (Alfredini et al, 2008). Surveys have shown high ammonium, phosphate and chlorophyll concentrations in the Santos estuarine complex year round (Gianesella et al, 2000;Aguiar and Braga, 2007), and changes in the phytoplankton species composition and size structure (mainly diatoms, dinoflagellates and mixotrophic dinofalgellates) have been related to freshwater input, tides and wave action (Moser et al, 2012).…”