Author(s): Fuma Tanaka; Takao Tamura; Yasunori Muto
Linked Author(s): Yasunori Muto
Keywords: Flood flow; H-Q formula; GSMaP; Calibration; Water level
Abstract: Developing countries don’t have abundant hydrologic information such as ground-based rainfall observed in a basin and the flow rate observed in a river channel, so it is difficult to adopt runoff analysis. In this study, the runoff analysis system was constructed satellite-based rainfall and water level which are easy to obtain in developing countries. GSMaP was used as a satellite-based rainfall. However, the satellite-based rainfall is not so accurate. So, it is corrected using rain area movement information and cumulative ground-based rainfall information. Then, using the corrected satellite-based rainfall, the water level hydrograph is estimated by runoff model built-in H-Q formulation and consider the reproduction accuracy in the Naka River of Tokushima Prefecture in Western Japan with abundant hydrologic information. The rainfall for the runoff analysis was observed in Typhoon No. 11 in 2014. By performing the correction using rain area movement information and cumulative ground-based rainfall information, the determination coefficient between satellite-based rainfall and ground-based rainfall coefficient improved from -5.55 to 0.76. The error value between the observed water level and the estimated water level (for 7 hours before and after flood peak) decreased from 58% to 9%.
Year: 2018