TY - JOUR AU - Nicolodi, Joao Luiz AU - de Figueiredo, Salette Amaral AU - Toldo Jr. , Elirio AU - Julio Calliari, Lauro PY - 2021/12/31 Y2 - 2024/03/29 TI - Regional Coastline Changes and Future Predicted Scenario on Southern Brazil. JF - Revista Geográfica de Chile Terra Australis JA - Rev. geogr. Chile, Terra Australis VL - 1 IS - 1 SE - Articles DO - 10.23854/07199562.2021571esp.Nicolodi76 UR - https://www.revistaterraaustralis.cl/index.php/rgch/article/view/84 SP - 76-95 AB - <p>The Rio Grande do Sul (RS) coastline consists of a 615 km long sandy barrier, with a NE-SW orientation. It is characterized by alternating slightly concave and convex segments extending from the rocky headlands at Torres up to the Chuí stream, at the Uruguayan border. In general, the genesis of this geographical area is related to changes in sea level in the Quaternary, when a complex Lagoon-barrier system was created. This study presents a compilation of decades of studies about short-term monitoring and long-term projections conducted by the two local main research centers on the subject. In this study, trends in shoreline behavior between 2002 to 2013 were analyzed. Results indicated that 43,5% of the coastline was stable, 41% was under moderate erosion, 9% in moderate progradation, 3% under pronounced progradation, and 3,5% under severe erosion. The specific causes of these variations are not yet fully understood. However, some factors are likely to be responsible for coastline behavior in the long and short term: geological inheritance which influenced coastline orientation, regional sediment budget, as well as shoreface gradient and bathymetry. The main erosive hotspots found along the RS coastline are influenced by wave energy focus due to refraction caused by the local bathymetric features and coastline orientation. The Cassino Beach sector, however, has a pronounced progradation which in the long term can be mainly related to its coastline orientation, and more recently due to jetties built at the Patos Lagoon inlet, which provided more sediment retention of the prevailing net longshore drift to the northeast. This study also offers a review about shoreline changes along the four existing inlets. Coastal vulnerability to sea-level rise (SLR) analyzed through coastline recession distances in long-term scenarios (2030 and 2100) indicated that the most vulnerable sectors are those located along coastal embayments, which coincide with low gradient shorefaces.</p> ER -