Improvement of an index oriented methodology for consequence analysis of natural hazards: application to the Upper Guil Catchment (Southern French Alps)

Abstract

10Vulnerability is a complex concept involving a variety of disciplines from physical and socio-economic sciences. Currently, two opposite trends exist: the physical approach in which vulnerability is analysed as potential impacts on the exposed elements; and the social approach in which vulnerability is viewed as a combination of socio-economic variables determining people's ability to anticipate before a catastrophic event, to react during it, and to recover after it. Finding a way to combine these two approaches is a key issue for a global vulnerability 15 assessment. The objective of this paper is to improve the Potential Damage Index (Puissant et al., 2013) originally developed to assess the physical, structural and functional consequences of landslide hazard, by including social and institutional criteria. These criteria, derived from INSEE French census data and risk perception survey were selected to represent the three main phases of risk management: preparedness, crisis management and recovery. The new Global Potential Damage Index is then applied on the Upper Guil Catchment to assess torrential floods. 20Results of the PDI are compared with the GPDI and show significant differences. GPDI scores are globally lower than PDI scores indicating that resilient population may qualify results obtained for physical consequences.