Gomes, Moab PraxedesDamasceno, Úrsula Martin2025-03-262025-03-262024-11-20DAMASCENO, Úrsula Martin. Hidrodinâmica em cânions submarinos da margem continental do Rio Grande do Norte. Orientador: Dr. Moab Praxedes Gomes. 2024. 117f. Tese (Doutorado em Geodinâmica e Geofísica) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2024.https://repositorio.ufrn.br/handle/123456789/63252Physical processes at continental margins control the transport of heat, sediments, chemical compounds, and nutrients between the ocean basin and the continental shelf, which affects the ecosystems nearby. The shelf-edge submarine canyons interact with the currents and are potential flow channelers between the coastal zones and the oceanic basin. Despite the importance of these phenomena, canyon-flow interactions in low latitudes of the Atlantic Ocean are poorly understood. This study aims to characterize the hydrodynamic phenomena of the Brazilian tropical margin, specifically the submarine canyons in areas of shelf break zones on the eastern and northern shores of Rio Grande do Norte (RN). Physical processes were investigated using the Coastal Regional Oceanic Community Model (CROCO). The first analysis presented here pertains to the Natal Canyon and was developed in CROCO using regional bathymetry interpolated from nautical charts and global databases, validated with in situ data. This study aims to analyze the hydrodynamics of the Natal Canyon and its effects on the exchange between the shelf and the ocean, and suspended particles. The correlation analysis includes the components of canyon flow, the North Brazil Current, the transport of the outer-middle shelf, and wind stress. Additionally, a drifter model was built using the velocity field of the oceanic model with the Ichthyop model for three different positions: on the southern edge of the canyon, at the head of the canyon, and along the current path on the slope. The results show two main forces driving the canyon dynamics: i) the meridional wind, which has the highest correlation coefficient with canyon transport (-0.75), and ii) the North Brazil Undercurrent with the second highest correlation coefficient (-0.64). In all three simulated scenarios, the current isstrong enough to transport most of the suspended particles (~95%) northward. Despite the general westward transport of the canyon, the current is not strong enough to prevent the capture of particles (~2%) within the canyon. A small portion of particles (<2%) reaches the inner shelf through the canyon head and the coastal current. The results indicate that the dynamics of the Natal Canyon are wind- driven and favor downward flow. This context impacts suspended particles and may explain the starved condition in low-latitude shelves, such as the eastern margin of Rio Grande do Norte, Brazil.Acesso AbertoCânions submarinosCorrente de contorno oesteTalude continentalMargem equatorialdoctoralThesisCNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS