|UNESCO World Heritage sites (WHS) located in coastal areas are increasingly at risk from coastal flooding due to accelerated sea-level rise (SLR). So far, limited work has been conducted on assessing the impacts of SLR on WHS, leaving stakeholders and policymakers with little information on adaptation needs. A recent regional assessment for the entire Mediterranean region found up to 85 % of cultural UNESCO WHS located in low-lying coastal areas to be at risk from a 100-year storm surge until 2100, depending on the SLR scenario considered. Further, flooded area and flood depth at WHS increased with SLR (Reimann et al. in review). This regional scale study employed a simple approach for modelling coastal inundation (‘bathtub method’, BT). In the present study, we compare different approaches for assessing inundation characteristics for selected WHS along the northern Adriatic Sea, which are among the WHS most at risk from coastal flooding, and assess exposure to the same surge heights using a hydrodynamic modelling approach (HD). Preliminary results confirm previous findings, suggesting that the flood extent of a HD approach is smaller than that of the BT approach, with a particularly high difference in mildly sloping terrains. Differences in flood extent seem to be less pronounced in steep terrains. The results of this study provide insights into how regional assessments relate to results produced using more detailed data and modelling approaches at local scale and to what extent the former can inform policy or management decisions regarding adaptation strategies at WHS.
Reimann, L, Vafeidis, AT, Brown, S, Hinkel, J, Tol, RSJ (in review): Mediterranean UNESCO World Heritage at risk from coastal flooding and erosion due to sea-level rise. In Nature communications.