Author(s): Shiori Abe; Satoshi Watanabe; Yosuke Nakamura
Linked Author(s):
Keywords: Climate change; d4PDF; Flood discharge; RRI model
Abstract: This study assessed the impacts of climate change on river discharge in small and medium-sized basins, focusing on flood risk management in Minami Town, Tokushima Prefecture, Japan. The bias-corrected d4PDF-5 km dataset was used to assess future changes in river flow. Annual maximum 24-hour basin-average rainfall was used as input to the RRI (Rainfall–Runoff–Inundation) model to simulate runoff, and the 50-year return period discharge was estimated. The results showed that peak discharges increased under future climate conditions, with greater increases in upstream and smaller basins. These projected changes may differ from rainfall change factors in the national proposal on flood control planning, suggesting that basin-specific analyses are needed when revising flood plans. Moreover, the d4PDF-5km dataset was effective in representing spatial rainfall variations and assessing climate change impacts in small catchments, demonstrating its usefulness for local-scale flood risk assessment.
Year: 2026