From theory to practice: optimisation of available information for landslide hazard assessment in Rome relying on official, fragmented data sources

The definition of landslide hazard is a step-like procedurethat encompasses the quantification of its spatial and temporalattributes, i.e., a reliable definition of landslide susceptibility and adetailed analysis of landslide recurrence. However, available informationis often incomplete, fragmented and unsuitable for reliablequantitative analysis. Nevertheless, landslide hazard evaluation hasa key role in the implementation of risk mitigation policies andan effort should be done to retrieve information and make it usefulfor this purpose. In this research, we go through this topic ofoptimising the information available in catalogues, starting fromlandslide inventory review and constitution of a boosted trainingdataset, propaedeutic for susceptibility analysis based on machinelearning methods. The temporal recurrence of landslide events hasbeen approached here either through the definitions of large-scalequantitative hazard descriptors or by analysis of historical rainfall(i.e., the main triggering factor for the considered shallow earthslope failures) databases through the definition of rainfall probabilitycurves. Spatial and temporal attributes were integrated, selectingpotential landslide source areas ranked in terms of hazard. Dataintegration was also pursued through persistent scatterer interferometryanalysis which pointed out areas of interest within potentiallandslide source areas featured by ongoing ground movement.The consequential approach led to the definition of the first hazardproduct of the city of Rome at a local scale functional for advisorypurposes or the statutory level, representing a thematic layer ableto orient the risk managers and infrastructure stakeholders