Evidencing sources of flood disaster policy improvement leveraging flood risk attributes in India

Climate change has contributed to shifting extreme events' frequency, intensity, spatial extent, duration, and timing, affecting communities and regions worldwide. Yet, disaster governance grapples with addressing the effects of emerging and unexpected spatiotemporal patterns of hydroclimatic variability on the built and natural systems. This study aims to create a workflow to identify sources of flood disaster governance improvement using flood risk attributes for three major flood events at state and district levels in India. The flood risk-based framework quantifies vulnerability, exposure, and hazard to evidence the potential critical drivers of flood disaster improvement in the affected areas. Three major flooding events occurred between 2005 and 2020 in India's Maharashtra, Uttarakhand, and Assam states are characterized by their hazard, vulnerability, and exposure risk attributes. A comprehensive compilation of precipitation anomalies, augmented by media data and hazard mapping flow accumulation (F), rainfall intensity (I), geology (G), land use (U), slope (S), elevation (E) and distance from the drainage network (D) and global sensitivity analysis (FIGUSED-GSA), presiding over the estimation of flood exposure (using runoff Peak-over-threshold return periods), socio-economic vulnerabilities (using the equal weightage method), and risk (as a product of hazard, exposure and vulnerability). These methods will be useful for the data scarce regions as well. The estimates of flood risk and its components will aid in highlighting the areas of possible actions needed to create more effective flood governance frameworks at both the state and district level.