## 4 Results
### Inundation Maps  
In this section, we present inundation maps for the three reference periods, for each study area. The flooded areas are represented by the water level rise on the coastal DTM of 2010, without considering the morphological effects during the inundation processes [51]. Raster images of cumulative flood maps are shown in Figures 8-12. Surface Under Sea Level (SUSL) refers to areas that will be at a lower elevation compared to the mean sea level of 2010, under future scenario conditions, and they are indicated by the blue colour. In general, all maps show an increase in the flooded areas through time, but the consequences in terms of vulnerability and risks vary from region to region, as described below. Surface Under Sea Level (SUSL) refers to the baseline digital terrain model (DTM) of 2010. The area of Piombino-Follonica (Figure 8) has a surface of 24.4 km\({}^{2}\); it contains 6,095,979 DTM cells and 2417 EGMS cells (59% coverage). The study area is dedicated to agriculture, harbour activities, and energy production. The effects of cultivation and tillage (ploughing) are evident on the shore. Progressive flooding scenarios, due to RSRL, can be observed in a series of subparallel narrow strips of cultivated land. Figure 8: Follonica inundation map (24.4 km\({}^{2}\)) under RCP8.5 scenario. The 2010–2040 (SUSL = 1.36 km\({}^{2}\)), 2040–2070 (SUSL = 2.72 km\({}^{2}\)), and 2070–2099 (SUSL = 4.57 km\({}^{2}\)) periods are represented with scaled blue colours, with the DTM of 2010 in the background. The SLR used for the projection is reported close to the colour bar (cm). Figure 9: Marina di Campo inundation map (11.1 km\({}^{2}\)) under RCP8.5 scenario. The 2010–2040 (SUSL = 0.04 km\({}^{2}\)), 2040–2070 (SUSL = 0.06 km\({}^{2}\)), and 2070–2099 (SUSL = 0.09 km\({}^{2}\)) periods are represented with scaled blue colours, with the DTM of 2010 in the background. The SLR used for the projection is reported close to the colour bar (cm). The lower panels show zoomed-in details of the areas where flood vulnerability increases through time. The area of Marina di Campo (Figure 9) has a surface of 11.1 km\({}^{2}\); it contains 2,49,679 DTM's cells and 1087 EGMS's cells (51% coverage). This coastal plain is characterized by a network of natural and artificial waterways and irrigation channels and hosts an important airport infrastructure. Flood maps show that during the 21 st century, the most vulnerable portions of land are adjacent to the airport and to the banks of water courses. Figure 10: Fertilia inundation map (68.5 km\({}^{2}\)) under RCP8.5 scenario. The 2010–2040 (SUSL = 0.99 km\({}^{2}\)), 2040–2070 (SUSL = 1.13 km\({}^{2}\)), and 2070–2099 (SUSL = 1.44 km\({}^{2}\)) periods are represented with scaled blue colours, with the DTM of 2010 in the background. The SLR used for the projection is reported close to the colour bar (cm). The lower panel shows the flood vulnerability through time of the Stagno di Calich shores. The area of Alghero-Fertilia (Figure 10) has a surface of 68.5 km\({}^{2}\); it contains 2,739,980 DTM's cells and 6804 EGMS's cells (37% coverage). The Calich, which is both a fishpond and a lagoon, is among the most important coastal wetlands of Sardinia [89]. It overlooks the coast of Alghero and is connected to the sea by a channel where the remains of a Roman bridge can be found. Flood maps show that portions of its banks will be affected by flooding, with consequent ecological changes for flora and fauna. By the end of the century, the armoured mouth and Fertilia Harbour could be submerged. Figure 11: Rome inundation map (51.6 km\({}^{2}\)) under RCP8.5 scenario. The 2010–2040 (SUSL = 1.99 km\({}^{2}\)), 2040–2070 (SUSL = 3.31 km\({}^{2}\)), and 2070–2099 (SUSL = 5.84 km\({}^{2}\)) periods are represented with scaled blue colours, with the DTM of 2010 in the background. The SLR used for the projection is reported close to the colour bar (cm). The area of Rome (Figure 11) has a surface of 51.6 km\({}^{2}\); it contains 12,901,334 DTM's cells and 5153 EGMS's cells (44% coverage).