Multi-hazard Susceptibility Model based on Very-High-Resolution data – a case study of Sali settlement (Dugi otok, Croatia)

Abstract

Abstract The world has been facing an increase in various natural hazards. The coastal regions are recognized as one of the most vulnerable due to high population pressure and climate change intensity. Mediterranean countries are one of the most burnable ecosystems in the world, one of the most exposed to pluvial floods, and have the highest erosion rates within the EU. Therefore, the aim of this study was to develop the first multi-hazard susceptibility model in Croatia for Sali settlement (island of Dugi otok). The creation of a multihazard susceptibility model (MHSM) combined the application of geospatial technology (GST) with a local perception survey. The methodology consisted of two main steps: (1) creating individual hazard susceptibility models (soil erosion, wildfires, pluvial floods), and (2) overall hazard susceptibility modeling. Multicriterial GIS analyses and Analytical Hierarchy Process were used to create individual hazard models. Criteria used (32) to create models are derived from very-high-resolution (VHR) models. Two versions of MHSM are created: 1) all criteria with equal weighting coefficients and 2) weight coefficients determined based on a public perception survey. Both models had similar results and reveal moderate susceptibility of Sali to multiple hazards. The public perceives that the research area is the most susceptible to wildfires. The greatest difference between public perception and the GIS-MCDA model of hazard susceptibility is related to soil erosion. However, the accuracy of the soil erosion model was confirmed by ROC curves based on recent traces of soil erosion in the research area. The proposed methodological framework of multihazard susceptibility modeling can be applied, with minor modifications, to other Mediterranean countries.