空撮・衛星画像と数値解析を用いた東日本台風時の那珂川流域における浸水状況の推定

抄録

Typhoon Hagibis passed through Japan on October 12, 2019, brought heavy rainfalls over half of Japan, and resulted in flooding in wide areas. This study focuses on a flooded state-managed river, the Naka River, Ibaraki Prefecture, Japan. In this study, we conducted the field survey on October 28, 2019, after the typhoon passed. Additionally, a series of runoff analyses for the entire Naka River basin and inundation analyses for some sections of the Naka River were conducted. Comparing the results of numerical simulation with the inundated areas detected by aerial and satellite Synthetic Aperture Radar (SAR) images, the accuracy of the numerical simulation was investigated. The maximum F value was 78.65%, and the simulated result broadly coincided with the inundated areas.