Toward economic flood loss characterization via hazard simulation

Among all natural disasters, floods have historically been the primary cause of human and economic losses around theworld. Improving flood riskmanagement requires amulti-scale characterization of the hazard and associated losses—theflood loss footprint. But this is typically not available in a precise and timelymanner, yet. To overcome this challenge, we propose a novel andmultidisciplinary approachwhich relies on a computationally efficient hydrologicalmodel that simulates streamflow for scales ranging from small creeks to large rivers.We adopt a normalized index, the flood peak ratio (FPR), to characterize floodmagnitude acrossmultiple spatial scales. The simulated FPR is then shown to be a key statistical driver for associated economic flood losses represented by the number of insurance claims. Importantly, because it is based on a simulation procedure that utilizes generally readily available physically-based data, ourflood simulation approach has the potential to be broadly utilized, even for ungauged and poorly gauged basins, thus providing the necessary information for public and private sector actors to effectively reduce flood losses and save lives.