## 2 Materials and Methods
### Sea-Level-Rise Scenario  
During the last decades, several investigations on SLR have been carried out, as many projections from observed data have been proposed. One of the key questions related to the development of a future scenario is where the estimation should be provided. Bearing in mind the high variability of SLR at both regional scale and local level, the term SLR should be read in the sense of Global Mean Sea Level (GMSL) rise. Since 1880, the GMSL has increased by about 21 to 24 cm, with about 8 cm occurring since 1993 [42; 43; 44]. Moving from those observed data, a wide range of estimates for GMSL rise scattered throughout the scientific literature can be found, along with the lack of any coordinating interagency effort. A scientific synthesis across the large range of published future GMSL was described by [45]. They developed a set of four scenarios, spanning a range of 0.2 to 2.0 m by the year 2100, that described potential future GMSL conditions under varying assumptions about climate change and the behavior of large ice sheets. However, the key advance of that study was the complement of the existing scientific assessments (e.g., from the Intergovernmental Panel on Climate Change, IPCC [46]) by presenting the science from the perspective of scenario analysis within a risk-based context. Practically, instead of addressing the question \"What is most likely to occur?\", the research of the long-term SLR should be read in terms of \"How bad could things get?\" [47]. In fact, traditional scientific assessment can often diverge from the goals of packaging science needed to support assessment and management of risk [48]. For instance, the IPCC Fifth Assessment Report [46] stresses the central or 'likely' range of 21 st century rise in GMSL based primarily on process-based models. As explained in [49], the 'likely' range is assessed as having at least a 66% probability of containing the true value. Given such a 33% chance that GMSL rise falls outside of this range, some risk-averse decision-makers may find the IPCC's 'likely' range inadequate for their planning purposes (for instance, a nuclear power plant near the coastal zone might be more interested in the 99 th percentile, as highlighted by [47]). Clearly, a detailed review or study of long-term SLR scenarios are out of the scope of the present paper. However, in order to define a methodology, a selection of a specific pattern is required. Several studies assumed the SLR to be linear during the 21 st century: for instance, [PERSON] et al. [16] investigated an extreme rate of 1.0 m rise in 2100. At the European level, [PERSON] et al. [17] provided an estimation of regional mean sea level changes for five tide gauges in different parts of Europe: for all the locations, the 95-percentile maxima of GMSL derived from the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) projections arises about 0.8 m in 2080. One recent study [50] estimates that 0.9 m of sea level rise would permanently inundate areas currently home to 2 million Americans. The value of 0.9 m corresponds to the median under the Representative Concentration Pathway 8.5 (RCP8.5) emission scenario [51], in which a 2 \({}^{\circ}\)C warming relative to the preindustrial period is expected by 2041, reaching 4 \({}^{\circ}\)C by 2083, continuing to a median projected warming of almost 5 \({}^{\circ}\)C by 2100 [52; 53]. Moreover, 0.9 m is suggested by European  
Figure 7: Photos showing the nose in (**a**) small configuration, (**b**) large configuration and (**c**) extra-large configuration. Community as the SLR value which will probably face almost all of the world's 136 largest coastal cities by 2100 [54]. Therefore, a value of 0.9 m has been considered as the future scenario of sea level during the present experimental campaign.