ESTIMATION OF POTENTIAL DAMAGE COST ON FLOOD AND STORM SURGE DISASTERS UNDER SAME RETURN PERIOD

The potential damage cost of flood and storm surge in whole Japan was estimated quantitatively. We also estimated the potential damage cost on flood and storm surge in compound disaster that two disasters happened in the same time. The error of damage cost on compound disaster was evaluated. We extracted larger risk disaster than others in each Japanese prefecture. The error of damage cost estimated on compound disaster was similar to change estimation by using future scenarios and GCMs. The potential damage cost of flood in whole Japan was 1.04 trillion USD, storm surge was 0.52 trillion USD and compound disaster of flood and storm surge was 0.88 trillion USD. Out of 46 prefectures, the damage cost of flood was larger than others in 37 prefectures. Additionally the damage cost of storm surge and compound disaster were larger than others in 1 and 8 prefectures in Japan, respectively.