## 3 Results
### Hazard Assessment
#### 3.2.2 Quantitative Investigation  
The hazard quantitative assessment results in four hazard maps showing the single-hazard classification at the census tract level (Figure 7) based on the percentage of the territory potentially affected by LH and FH (HPH, MPH, and LPH). In the case of the LH scenario (Figure 7a), 32 census tracts fall in the very-high-hazard class (Level 5), 25 fall in the high-hazard class (Level 4), and 45 fall in the medium-hazard class (Level 3), mostly included in the municipalities of Pomarioo, Pisticci (northern area), Craco, Montalbano Jonico, Colobraro, Valsinni, and Nova Siri. In total, 65 census tracts are associated with the low-hazard class (Level 2), whereas 231 are related to the very-low-hazard class (Level 1), spatially distributed across all the municipalities apart from Policoro. As a main result  
Figure 6: Hazard qualitative distribution derived from the codification process (Table 1) in different study area sectors (**a**) at the census tract level. Magnified view of the northern (**b**), central (**c**), and southern sector (**d**). FH = flood hazard; LH = landslide hazard; MH = multi-hazard. The white lines represent the census tract boundaries. Basemap: Google Satellite.  
of landslide hazard quantitative analysis, the central sector of the study area (Figure 6a) coupled with the municipalities of Pomarico and Valsinni are the most exposed to LH.  
According to Figure 7b-d, all the municipalities intersected by FH show similar characteristics in the case of LPH, MPH, and LPH scenarios in terms of spatial distribution. The slight difference between these scenarios is the increments of the flood hazard classes from HPH to MPH and LPH in some census tracts mostly located on the Ionian coast. The municipalities of Bernalda, Scanzano Jonico, Pisticci, Policoro, and Nova Siri show the highest number of census tracts (296) and therefore represent the maximum percentage of the territory potentially affected by FH (Classes 4 and 5) in the case of HPH, MPH, and LPH.  
Figure 8 depicts the main outcome of the multi-hazard investigation, derived from the overlap between LH and FH (LPH, MPH, and HPH) scenarios. In this case, the spatial distribution of census tracts affected by multi-hazards is similar. Table 6 represents an example of the results derived from the application of the multi-hazard matrix (Section 2.1), showing the number of census tracts exposed to different multi-hazard classes in the case of LH + FH in the MPH scenario. Moreover, information about the qualitative multi-hazard classification is also provided to give information about the specific multi-hazard associated with the different classes. As a result, the majority of census tracts fall in low-multi-hazard classes (77), 7 census tracts belong to the medium multi-hazard level, and 23 are classified as having high multi-hazard. The municipalities with the highest number of census tracts affected by multi-hazard are Pisticci and Tursi. However, Pisticci shows the highest level of multi-hazard exposure.  
Figure 7: Classification of the census tracts based on the percentage of the territory affected by landslide hazard (**a**) and flood hazard in the high- (**b**), medium- (**c**), and low (**d**)-probability hazard scenarios. The numbers are classified as follows: 1 = very low; 2 = low; 3 = medium, 4 = high; 5 = very high. Basemap: Google Satellite.