Abstract
We defined hazard, exposure and vulnerability as the frequency and magnitude of natural disasters, the percentage of population that is exposed to natural disasters and the defects of society and economy to natural disasters, respectively. We evaluated them by weighted averaging of normalized data of past disaster records and statistics that are opened to public. We then calculated the integrated risk to five kinds of natural disasters including earthquake, tsunami, storm surge, sediment related disaster event, and volcanic activity by multiplying hazard, exposure and vulnerability. The results of disaster risk and vulnerability were presented in the prefectural scale in Japan and their tendency was discussed. We finally presented the way of applying the proposed risk index as a piece of scientific information for selecting highest priority measures for mitigation in a rational manner.
