ESTIMATION OF ANNUAL MAXIMUM RAINFALLS BASED ON A MASSIVE ENSEMBLE CLIMATE PREDICTIONS IN ACTUAL RIVER BASIN

Abstract

 In August 2016, three typhoons continuous attacked Hokkaido and heavy rainfall occurred in various places. As a result floods of rivers and sediment disasters occurred mainly in eastern of Hokkaido. Recently, there is concern that the impact of such climate change will become apparent. In this situation, flood control measures considering future climate change are required in Japan. The current flood control plan have set up safety standards based on observation data in the past, however it is essential to utilize climate prediction data to respond to events occurring under future climate change. In this study, we estimated annual maximum rainfall averaging per basin from output rainfall of climate model using d4PDF which is a massive ensemble climate predictions, and proposed methods to evaluate accuracy of this model. The results show that climate prediction data has high reproducibility of observation value, in addition its rainfall in subject basin will increase about 1.4 times in the future.