40-Year shoreline evolution in Italy: Critical challenges in river delta regions

Current global warming is causing a variation of different phenomena such as storm surges, sea level rise, and rainfall distribution, with possible consequences for the sandy coast areas. Over the last century, like a great part of the Mediterranean, Italy has been affected by a decrease in total yearly rainfall and by an increase in the occurrence of rapid and intense events. This has induced a change in rainfall distribution and, consequently, a potential impact on the environmental evolution. Our work uses the software CoastSat to investigate the past evolution of the sandy coastlines of Italy, with a particular focus on the period 1984–2024. Criticality was found in the river deltas, for which significant results were obtained: 66% of the 40 major rivers are currently experiencing coastal erosion; over 75% of these rivers have a hydrographic side affected by erosion. If we exclude the areas with a presence of coastal defences, 100% of the major rivers are affected by erosion. Our study highlights that river deltas in the Mediterranean area are particularly vulnerable to climate change when compared to the average behaviour of the area.