The frequency and severity of flood disasters has been increasing around the globe. Therefore, it is needed to evaluate and compare the risks among different countries and regions and to use the results of such analysis as a guide in formulating policy and countermeasures to prevent disasters and mitigate their impact. In this study, we categorized flood risk into four dimensions (exposure, basic vulnerability, soft countermeasures, and hard countermeasures) and used this categorization to calculate the flood risk for individual countries. We developed a methodology to compute Flood Risk Index by using global datasets combined with satellite remote sensing data, such as a Global Precipitation Measurement data and identified flood risk factors in different countries.The examples of the study’s outcomes are as follows.- Many of the countries with high flood risk are located near the equator in Southeast and South Asia. In these countries, the greatest contributing factor to high flood risk is increased hazard due to high precipitation.- Although Japan has a high hazard score due to high precipitation, flood risk remains relatively low thanks to high coping capacity scores stemming from factors such as the country’s high literacy rate.The significance of this study lies in the fact that we were able to collect, use, and analyze global monitoring data (from satellites and space-based radar) that contain flood-related data for developing countries, for which such information is scarce, as well as the fact that we were able to use these data to evaluate flood risk for different countries around the world by a consistent methodology. In addition, we demonstrated that the use of satellite data, which can be continuously collected, is an effective method for analyzing changes in flood risk over time. It is expected that the results of this study will be useful in the formulation of flood management policy. |