Author(s): Kenichiro Kobayashi; Yuichiro Oku; Eiichi Nakakita; Masuo Nakano; Kaorutakara
Linked Author(s): Kenichiro Kobayashi
Keywords: Pseudo-global warming experiment; Isewan Typhoon; Distributed rainfall-runoff/flood-inundation model; JMA-NHM; 195
Abstract: This paper deals with a methodology to assess the variations of flood hazard due to a climate change. First, Isewan Typhoon, a largest-ever Typhoon in Japan, is reproduced with JMA-NHM using observed atmospheric conditions as the control run (ctl). Then the pseudo global warming (pgw) experiment is carried out by changing the atmospheric conditions to those assuming a climate change. Thesesimulated rainfalls are given to a distributed rainfall-runoff/flood inundation (DRR/FI) model to assess the climate change impact on flooding. As the result, the simulated rainfalls of the control run (ctl) for the reproduction of the Isewan Typhoon as well as pgw experiment both by JMA-NHM exhibit that, though the 48-hrs rainfall of ctl underestimates the observation, the maximum hourly rainfall of pgw becomes much higher than the observation. Therefore, the simulated water level/discharge and inundation depth with pgw rainfall becomes all worse than those of the Isewan Typhoon.