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This paper presents a comprehensive study of headland bypassing around seven headlands with different orientations and degrees of wave and tide-induced current exposure, located on the northern shore of Santa Catarina island, southern Brazil. It encompasses an extensive dataset including detailed in situ measurements of bathymetry, beach profiles, sediment transport (traps), waves, currents and tides. The entrained sediment decreased in magnitude towards the more sheltered coast while maintaining comparable sediment grain distributions, supporting the hypothesis of a connection between beaches. Based on in situ measurements, a numerical model was calibrated (waves, currents and tides) and validated, with errors representing 11% of the magnitude of the measurements. Furthermore, three sediment transport formulae were tested to identify the one that best reproduced the processes at the study site. A model using tides, winds and full wave spectra as input was run to identify the general (net) trend of annual sediment transport in the study area aiming to identify if/where headland bypassing occurs. The results show that headland sand bypassing does occur in the study area confirming the anticlockwise sediment transport pathway. The present work highlights the role of sediment bypassing on embayed-headland bound beaches, which are usually considered to be closed cells. [ABSTRACT FROM AUTHOR]

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Abstract: This paper presents a comprehensive review on the interaction between hydrodynamic processes, beach morphology and sedimentology at large scale coastal behaviour along the coastline of Santa Catarina, between Laguna and São Francisco Island, a microtidal east coast swell environment with headland and bay geomorphologies. The parabolic bay shape equation has proven to be a convenient and practical tool for studying the stability of the headland-bay beaches, tombolos, and salients in Santa Catarina. The beaches exhibit different patterns of sediment removal as a function of the degree of beach curvature. In highly curved beaches, there is a well-developed shadow zone and a range of morphodynamic conditions, from a sheltered low-energy beach adjacent to the downdrift headland to a high-energy exposed beach on the straight end of the headland-bay beach. The less curved beaches instead, tend to show more uniform behaviour since they are directly exposed to incident waves. There is no obvious relationship between average wave height and mean grain size, showing the importance of sediment source to characterize the sedimentary distribution patterns in the study area. The analysis of beaches showed that beach morphodynamics and sequence profiles for a bay–headland coast in a microtidal east coast environment is a function of geological inheritance (e.g., distance between headlands and orientation, nearshore and inner shelf morphology, coastal plain morphology, and sediment source), and hydrodynamic factors (wave conditions, oceanic wave exposure and relative tidal range). [Copyright &y& Elsevier]