Seiki Kawagoe

Evaluating the cost of flood damage based on changes in extreme rainfall in Japan

The fourth report of the Intergovernmental Panel on Climate Change (IPCC) provoked a significant amount of controversy, as experts have sought to apply it to climate change in Japan. In particular, the Ministry of Land, Infrastructure, Transportation, and Tourism (MLIT) organized a committee of experts responsible for implementing flood control policies (MLIT 2008). Japan is particularly vulnerable to flooding because of its steep geography and humid climate characterized by typhoons. Consequently, Japan has been coping with the problem of flood control for a long time (Takahasi and Uitto 2004). The number of floods, and, hence, the damage due to flooding, has increased since 2004. Even though these flood events may not be caused directly by climate change, many researchers are interested in the various problems of climate change and its broader implications for economic development.

Slope Hazard Risk Due to Rainfall Condition In Future

Extreme precipitation is forecasted by global warming with GCM (General circulation model). The water resource crisis and an increase in the disaster are feared with cause as extreme precipitation in the future. It is necessary to evaluate a high dangerous region by the spatial-temporal distribution to risk mitigation. The risk map is useful of counter measures planning. The situation of take a counter measure can be understood from the time change of the risk map. We made the risk maps of the slope hazard in JAPAN by using forecast climate data (RCM20Ver.2: JMA) and digital geographic information data. I evaluated slope hazard risks about Present climate(1981–2000), Near-future climate(2031–2050), Future climate(2081–2100). The risk indexes are slope failure probability and economic damage of each land use.