Agradecimentos: The authors thank the Oceanographic Institute of the University of São Paulo, the Institute of Geosciences of the State University of Campinas, the Spatial Analysis and Modelling Lab (SPAMLab) hosted at the Institute of Energy and Environment of the University of São Paulo, and the University of Guarulhos. This study was partially funded by the São Paulo Research Foundation (FAPESP grant #2020/12050-6). E.S. (#308229/2022-3), R.C.O. (#306931/2022-2), and C.H.G. (#311209/2021-1) are National Council for Scientific and Technological Development (CNPq) research fellows Ver menos

Abstract: As the interface between land and water, coastlines are highly dynamic and intricately tied to the sediment budget. These regions have a high functional diversity and require enlightened management to preserve their value for the future. In this study we assess changes to the São Paulo State (SE Brazil) coastline over the last 36 years. The study innovatively employs big data remote sensing techniques and multivariate statistical models to evaluate and generate erosion/accretion rates (1985–2021) relative to beach orientation and slope. Shoreline change rates have been obtained for sandy beaches at 485 one-kilometer-spaced transects. Our findings capture the complexity and heterogeneity of the analyzed coastline, at a regional and local scale. No association was found between shoreline changes and beach face orientation. Nonetheless, a dependency relationship was found between dissipative beaches with moderate to high accretion. Beaches facing south, with relative stability, were prone to sediment accumulation. Locations with slow accretion, like sandy spits and tombolo-protected beaches, were associated with dissipative beaches with moderate to high accretion. The southeast-oriented beaches are more prone to erosion due to storm waves from the south. Results provide a broad, fast, and relatively low-cost methodology that can be used in any sandy beach context, bringing essential information for coastal management and decision-making related to the use and occupation of the coastal zones Ver menos