Coastal vulnerability index for the indented coastline of Primorje-Gorski Kotar County, Croatia

The study explores the general vulnerability of the coastline, with a focus on assessing vulnerability using the coastal vulnerability index (CVI) along the highly indented coastline of Primorje-Gorski Kotar County (PGC), Croatia. Vulnerability was assessed every 25 m of the 1235 km long coastline by calculating the CVI based on five representative variables: geological setting, coastal slope in relation to terrain instabilities (rockfalls and landslides), significant wave height, coastal flooding, and beaches, which were also integrated into a single overall CVI. The length of the coastline, characterised by different relief forms, and the scale of available data required an adaptation of the commonly used methodology. The results show a low overall vulnerability, mainly due to the prevalence of relatively resistant carbonate sedimentary rocks along the coasts. However, almost a quarter of the investigated coastline is highly or very highly vulnerable to coastal flooding. Of particular concern is the fact that many of the most vulnerable areas are inhabited. Analyses at this scale are suitable for regional spatial planning. The results of the conducted research are available publicly online, which enables their practical application for planning and management of coastal areas. Adaptation to the impacts of climate change is highly dependent on the location itself, but overall, this assessment provides indications of the most vulnerable locations in the PGC, where it is necessary to limit interventions in the coastal area.