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The Understen-Märket trench is located in the Southern Quark and is the only deep-water connection between the Baltic Propper and the Gulf of Bothnia. Bathymetric mapping reveals a number of eroded channels and drift deposits exists on the seafloor, indicating that the area is heavily affected by current activity. Bottom current behavior in the area is not thoroughly understood, but generally in the BalticBasin, there is southward flowing fresh surface waters compensated by denser northward-flowing more saline bottom waters. The dominant direction of flow for bottom waters in the Southern Quark is northward. Northward speeds often exceed the threshold required to erode fine material on the seafloor. Using geophysical data and marine sediment cores, this study shows that current eroded channels and drift deposits in the Understen-Märket trench were initially formed in the late Holocene between 3 – 4kyr BP, during the transition from the Littorina to the Post Littorina stages of the Baltic Sea. Application of the sortable silt (SS) proxy for current sorting show three distinct regimes that closely match the assigned lithologic units (LU) based on core descriptions. Downcore grain size analysis of three marine sediment cores reveals a gradual boundary to sandy sediments that caps two of the cores recovered from an eroded channel. The third core was recovered from the drift deposit which mostly consists of silt. The progressive coarsening suggests that the current activity has increased during the late Holocene. A simplified model is presented that shows how moderate (20-50 m) shallowing of the sill, which has occurred in response to isostatic rebound between 8 and 4 kyr BP, could have generated the higher current speeds seen today. However, this should be explored using more advanced paleo-circulation models.

O complexo Estuarino Lagunar Cananéia Iguape abriga um dos ecossistemas mais preservados e sensíveis do Estado de São Paulo, tornando seu litoral Sul uma região de grande importância social e ecológica. Entretanto, a ocupação desordenada e deficiências no sistema de saneamento básico, especialmente durante os meses de verão, aliados ao aumento da influência da vazão do Rio Ribeira de Iguape na circulação local, vêm contribuindo para a alteração das condições costeiras e do estuário e aumento da poluição marinha. A circulação marinha tem um papel fundamental na dispersão ou concentração de poluentes que são despejados no meio marinho. Para analisar a influência da circulação marítima em uma das principais atividades socioeconômicas da região, a pesca, foram determinadas as características das variabilidades do nível do mar e das correntes na Área de Proteção Ambiental Marinha do Litoral Sul (APAMLS) e do Estuário Lagunar Cananéia Iguape, avaliando os efeitos meteorológicos e oceânicos na zona costeira do litoral sul do Estado de São Paulo, através de modelagem numérica. Foi elaborada uma breve caracterização socioeconômica e da atividade pesqueira dos municípios desta região, por meio de síntese de dados secundários. Pode-se constatar que, como esperado, a circulação no estuário lagunar Cananéia Iguape é fortemente influenciada pela maré astronômica na sua porção sul e pela descarga fluvial ao norte, sofrendo poucas alterações devido aos efeitos meteorológicos. Por outro lado, a circulação na área costeira que abrange a APAMLS, além de sofrer grande influência da vazão do Ribeira de Iguape ao norte, tem a magnitude das correntes intensificada pela ação dos ventos e da densidade da água. A circulação marinha influencia intensamente a pesca da região e o conhecimento desse processo é fundamental para a gestão integrada dos recursos naturais e do ambiente com o desenvolvimento sustentável do litoral sul paulista. A atividade pesqueira, que teve grande redução de importância econômica para a região, apesar de ainda ser fundamental, se apoia na captura de algumas espécies; mas os problemas associados ao exercício da pesca são complexos, necessitando de um grande esforço para serem solucionados, para que se possa alcançar um avanço atrelado à manutenção da qualidade ambiental para esta região ainda bastante preservada. O conhecimento da hidrodinâmica da região dá suporte às diretrizes de uma área de preservação, pois os efeitos da circulação marinha são marcantes na região costeira, inclusive nas zonas de pesca. Assim, o manejo da APAMLS deve considerar que as correntes são em geral mais fracas durante o verão do que nos demais períodos do ano; deste modo, a dispersão de poluentes no verão, quando ocorre o maior aporte devido ao aumento do turismo, é mais lenta do que no restante do ano. Outros aspectos da circulação marítima devem ser levados em conta nos planos de manejo, como a predominância das marés e vazões fluviais no interior do estuário e a grande influência meteorológica nas áreas costeira e de plataforma adjacentes. / The complex Estuarine Lagoon Cananeia Iguape houses one of the best preserved and sensitive ecosystems of the State of São Paulo, making its southern coast a region of great social and ecological importance. However, the disorderly occupation and deficiencies in the sanitation system, especially during the summer months, combined with the increasing influence of the flow of Iguape Ribeira River in local circulation, have contributed to the change of coastal and estuary conditions and increased marine pollution. The marine circulation plays a key role in the dispersion or concentration of pollutants that are discharged into the marine environment. To analyze the influence of ocean circulation in one of the main socio-economic activities in the region, fishing, a study was performed to determine the characteristics of the variability of sea level and currents in the Marine Protected Area of the South Coast (APAMLS) and Lagoon Estuary Cananeia Iguape, evaluating the meteorological and oceanic effects in the coastal zone of the south coast of São Paulo, through numerical modeling. A brief socioeconomic characterization about the fishing activity of the municipalities of the region was developed, through synthesis of secondary data. It can be seen that, as expected, the circulation in the lagoon estuary Cananeia Iguape is strongly influenced by the astronomical tide in its southern portion and the river discharge in the north, with small influence of weather effects. On the other hand, the circulation in the coastal area encompassing APAMLS is submitted to great influence of the flow of Iguape Ribeira in the north, and the magnitude of the currents is intensified by the wind and the water density. The marine circulation strongly influences fishing in the area and the knowledge of this process is essential for the integrated management of natural resources and the environment, to a sustainable development of São Paulo south coast. The fishing industry, which had great reduction of economic importance to the region, although still important, is based on the capture of some species; but the problems associated with fishing activity are complex, requiring a great effort to be solved, to achieve a progress to maintaining environmental quality in this still well preserved region. Knowledge of hydrodynamics of the region supports the guidelines of a conservation area , since the effects of marine circulation are striking in the coastal region, including in fisheries areas . Thus, the management of APAMLS should consider that the currents are weaker in general during the summer than in other times of the year ; thus the dispersion of pollutants in summer, when the largest contribution is due to increased tourism is slower than the rest of the year. Other aspects of ocean circulation must be taken into account in the management plans , as the dominance of the tides and river flows into the estuary and the weather great influence on coastal areas and adjacent platform.

O complexo Estuarino Lagunar Cananéia Iguape abriga um dos ecossistemas mais preservados e sensíveis do Estado de São Paulo, tornando seu litoral Sul uma região de grande importância social e ecológica. Entretanto, a ocupação desordenada e deficiências no sistema de saneamento básico, especialmente durante os meses de verão, aliados ao aumento da influência da vazão do Rio Ribeira de Iguape na circulação local, vêm contribuindo para a alteração das condições costeiras e do estuário e aumento da poluição marinha. A circulação marinha tem um papel fundamental na dispersão ou concentração de poluentes que são despejados no meio marinho. Para analisar a influência da circulação marítima em uma das principais atividades socioeconômicas da região, a pesca, foram determinadas as características das variabilidades do nível do mar e das correntes na Área de Proteção Ambiental Marinha do Litoral Sul (APAMLS) e do Estuário Lagunar Cananéia Iguape, avaliando os efeitos meteorológicos e oceânicos na zona costeira do litoral sul do Estado de São Paulo, através de modelagem numérica. Foi elaborada uma breve caracterização socioeconômica e da atividade pesqueira dos municípios desta região, por meio de síntese de dados secundários. Pode-se constatar que, como esperado, a circulação no estuário lagunar Cananéia Iguape é fortemente influenciada pela maré astronômica na sua porção sul e pela descarga fluvial ao norte, sofrendo poucas alterações devido aos efeitos meteorológicos. Por outro lado, a circulação na área costeira que abrange a APAMLS, além de sofrer grande influência da vazão do Ribeira de Iguape ao norte, tem a magnitude das correntes intensificada pela ação dos ventos e da densidade da água. A circulação marinha influencia intensamente a pesca da região e o conhecimento desse processo é fundamental para a gestão integrada dos recursos naturais e do ambiente com o desenvolvimento sustentável do litoral sul paulista. A atividade pesqueira, que teve grande redução de importância econômica para a região, apesar de ainda ser fundamental, se apoia na captura de algumas espécies; mas os problemas associados ao exercício da pesca são complexos, necessitando de um grande esforço para serem solucionados, para que se possa alcançar um avanço atrelado à manutenção da qualidade ambiental para esta região ainda bastante preservada. O conhecimento da hidrodinâmica da região dá suporte às diretrizes de uma área de preservação, pois os efeitos da circulação marinha são marcantes na região costeira, inclusive nas zonas de pesca. Assim, o manejo da APAMLS deve considerar que as correntes são em geral mais fracas durante o verão do que nos demais períodos do ano; deste modo, a dispersão de poluentes no verão, quando ocorre o maior aporte devido ao aumento do turismo, é mais lenta do que no restante do ano. Outros aspectos da circulação marítima devem ser levados em conta nos planos de manejo, como a predominância das marés e vazões fluviais no interior do estuário e a grande influência meteorológica nas áreas costeira e de plataforma adjacentes. / The complex Estuarine Lagoon Cananeia Iguape houses one of the best preserved and sensitive ecosystems of the State of São Paulo, making its southern coast a region of great social and ecological importance. However, the disorderly occupation and deficiencies in the sanitation system, especially during the summer months, combined with the increasing influence of the flow of Iguape Ribeira River in local circulation, have contributed to the change of coastal and estuary conditions and increased marine pollution. The marine circulation plays a key role in the dispersion or concentration of pollutants that are discharged into the marine environment. To analyze the influence of ocean circulation in one of the main socio-economic activities in the region, fishing, a study was performed to determine the characteristics of the variability of sea level and currents in the Marine Protected Area of the South Coast (APAMLS) and Lagoon Estuary Cananeia Iguape, evaluating the meteorological and oceanic effects in the coastal zone of the south coast of São Paulo, through numerical modeling. A brief socioeconomic characterization about the fishing activity of the municipalities of the region was developed, through synthesis of secondary data. It can be seen that, as expected, the circulation in the lagoon estuary Cananeia Iguape is strongly influenced by the astronomical tide in its southern portion and the river discharge in the north, with small influence of weather effects. On the other hand, the circulation in the coastal area encompassing APAMLS is submitted to great influence of the flow of Iguape Ribeira in the north, and the magnitude of the currents is intensified by the wind and the water density. The marine circulation strongly influences fishing in the area and the knowledge of this process is essential for the integrated management of natural resources and the environment, to a sustainable development of São Paulo south coast. The fishing industry, which had great reduction of economic importance to the region, although still important, is based on the capture of some species; but the problems associated with fishing activity are complex, requiring a great effort to be solved, to achieve a progress to maintaining environmental quality in this still well preserved region. Knowledge of hydrodynamics of the region supports the guidelines of a conservation area , since the effects of marine circulation are striking in the coastal region, including in fisheries areas . Thus, the management of APAMLS should consider that the currents are weaker in general during the summer than in other times of the year ; thus the dispersion of pollutants in summer, when the largest contribution is due to increased tourism is slower than the rest of the year. Other aspects of ocean circulation must be taken into account in the management plans , as the dominance of the tides and river flows into the estuary and the weather great influence on coastal areas and adjacent platform.

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / The Amazon river, located in northernBrazil, discharges between 80,000 and 250,000 m3s-1 of water onto the adjacent shelf, creating a plume of brackish water that extends hundreds of kilometers away from the river mouth. This river also carries a large amount of fine sediments to the ocean where fluid mud has been found in the topset and upper foreset layers of the subaqueous delta formed on the mid-shelf. One of the main goals of this dissertation is to describe how turbulence and suspended sediment concentration vary along the Northern Channel of the Amazon river. Water column measurements were carried out in October 2008 at six anchor stations (P1, P3, P5, P6, P8 e P9) located seaward of the river mouth; P1 and P9 were 125 km apart. Each station was occupied during 13 hours during which current speed and direction were continuously sampled with a 600 kHz Teledyne-RDI ADCP; hourly profiles of temperature, salinity, turbidity and depth were also obtained. Water samples were collected for determination of Suspended Particulate Matter (SPM) concentration and calibration of the turbidity sensor. Current speed reached values above 1.5 m s1 in the along-channel direction (NE-SW); a remarkable ebb-flood asymmetry was observed and flows were strongly ebb-dominated. Throughout the water column, SPM concentration at stations P1 and P3 varied between 100 and 300 mg L1 in association with the presence of freshwater. In contrast, a strong salinity gradient was observed between stations P6 and P9, coinciding with the occurrence of concentrations of SPM above 10 g L-1 (fluid mud). At stations P3, P5 and P6, interface between freshwater from the Amazon river and salt water from the continental shelf, shear stresses wereestimated through four diferents methods: Reynolds, Turbulent Kinetic Energy (TKE), modified TKE and Quadratic Law; in the nearbed region (3 mab) the computed values varied between 0 and 3 Pa. At the three stations (P3, P5 and P6) the lowest and the highest shear stress values were obtained through, respectively, the Reynolds and the TKE methods. Over the whole water column turbulence intensity was estimated through the standard deviation of the turbulent component of the along-channel current velocity (root-mean square of u); from these values, it was estimated the turbulent dissipation of energy (G), whose values at 3 mab varied between zero and 20 s1.

Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / The Amazon river, located in northernBrazil, discharges between 80,000 and 250,000 m3s-1 of water onto the adjacent shelf, creating a plume of brackish water that extends hundreds of kilometers away from the river mouth. This river also carries a large amount of fine sediments to the ocean where fluid mud has been found in the topset and upper foreset layers of the subaqueous delta formed on the mid-shelf. One of the main goals of this dissertation is to describe how turbulence and suspended sediment concentration vary along the Northern Channel of the Amazon river. Water column measurements were carried out in October 2008 at six anchor stations (P1, P3, P5, P6, P8 e P9) located seaward of the river mouth; P1 and P9 were 125 km apart. Each station was occupied during 13 hours during which current speed and direction were continuously sampled with a 600 kHz Teledyne-RDI ADCP; hourly profiles of temperature, salinity, turbidity and depth were also obtained. Water samples were collected for determination of Suspended Particulate Matter (SPM) concentration and calibration of the turbidity sensor. Current speed reached values above 1.5 m s1 in the along-channel direction (NE-SW); a remarkable ebb-flood asymmetry was observed and flows were strongly ebb-dominated. Throughout the water column, SPM concentration at stations P1 and P3 varied between 100 and 300 mg L1 in association with the presence of freshwater. In contrast, a strong salinity gradient was observed between stations P6 and P9, coinciding with the occurrence of concentrations of SPM above 10 g L-1 (fluid mud). At stations P3, P5 and P6, interface between freshwater from the Amazon river and salt water from the continental shelf, shear stresses wereestimated through four diferents methods: Reynolds, Turbulent Kinetic Energy (TKE), modified TKE and Quadratic Law; in the nearbed region (3 mab) the computed values varied between 0 and 3 Pa. At the three stations (P3, P5 and P6) the lowest and the highest shear stress values were obtained through, respectively, the Reynolds and the TKE methods. Over the whole water column turbulence intensity was estimated through the standard deviation of the turbulent component of the along-channel current velocity (root-mean square of u); from these values, it was estimated the turbulent dissipation of energy (G), whose values at 3 mab varied between zero and 20 s1.