# Methodology for the Assessment of Multi-Hazard Risk in Urban Homogeneous Zones
## 1 Introduction
Namely, high vulnerability of some areas can result in severe losses during a low-intensity hazard, and low vulnerability can result in minor losses during a high-intensity hazard. Many different criteria are used for vulnerability calculation, because the criteria set is also defined by the type of hazard [4]. However, assessing the vulnerability to natural hazards such as earthquakes can be characterized as an ill-structured problem or a problem without unique, \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Approach**} & \multicolumn{4}{c}{**Factors**} & \multirow{2}{*}{**Output**} & \multirow{2}{*}{**Source**} \\ \cline{2-2} \cline{4-6}  & **Frequency** & **Intensity** & **Vulnerability** & & **Other** \\ \hline Single hazard & Yes & No & No & Damage & Risk & [PERSON] et al. [6] \\ Multi-hazard & Yes & Yes & Yes & Coping capacity & Risk & [PERSON] et al. [7] \\ Multi-hazard & No & Yes & Yes & Coping capacity & Integrated risk & [PERSON] et al. [5] \\ Single hazard & Yes & Yes & No & No & Risk & [PERSON] et al. [8] \\ Multi-hazard & Yes & Yes & Yes & Consequence (loss) & Risk & [PERSON] et al. [9] \\ Multi-hazard & Yes & No & No & Aggregated losses & Risk & [PERSON] et al. [10] \\ Single hazard & No & No & Yes & Hazard exposure, & Risk index & Munich Re Group [11] \\ Single hazard & Yes & Yes & No & Area impact & Hazard score & Odeh Engineers, Inc. [12] \\  & & & & Elements at risk, & & \\ Multi-hazard & Yes & Yes & Yes & Temporal/Spatial & Risk & [PERSON] [13] \\  & & & & probability & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Brief literature survey on factors used to calculate the risk of natural hazards. identifiable and objectively optimal solution. A review of the literature indicates a number of contrasting definitions of what vulnerability means, as well as numerous conflicting perspectives on what should or should not be included within the broad assessment of vulnerability in cities [19]. For instance, some authors also include coping capacity (emergency units) of the area in the vulnerability analysis [5]. But this is not necessarily a good approach, since coping capacity is something that can dynamically change each year, and other common vulnerability criteria (building age, building structure, building height, etc.) are less or more static. Furthermore, it is important to mention that different vulnerability analyses are used at different scales [20]. The different criteria sets (factors) are used and sometimes different methods must be used, as well. The aim of this study is the assessment of multi-hazard risk for Kastel Kambelovac, a small city placed along the Adriatic Sea near the city of Split, Croatia (Figure 1). Due to its location in a zone of high seismic risk and considering the large number of stone-made and several-centuries-old historical buildings, Kastela is a settlement with pronounced seismic vulnerability and risk [18]. The historical center, built right next to the low-lying coast, is also threatened by floods due to rising sea levels caused by climate change. Furthermore, the settlement is exposed to flooding caused by extreme sea waves generated by severe wind. Therefore, the present multi-hazard risk assessment is aimed at determining the combined risk of the settlement caused by earthquakes, sea floods and extreme sea waves. The multi-hazard risk investigation of the Kastel Kambelovac is a part of the project \"Preventing, managing, and overcoming natural-hazards risks to mitigate economic and social impact\" (PMO-GATE) [24]. The main challenge in the multi-hazard risk assessment is to evaluate, use and mutually compare different mathematical variables that describe the hazard's frequency, intensity and vulnerability. In this research, this issue is addressed by using the multi-criteria analysis that is commonly used to evaluate and compare quantitative and qualitative criteria in completely different units and the order of magnitude. However, a proper multi-criteria analysis must be selected.