New publication

The efforts of Dr Josko is now published as follows. Congratulations.

  1. Trošelj J. and Lee H.S. 2021. Modelling Typhoon-induced Extreme River Discharges: A case study of Typhoon Hagibis in Japan. J. Hydrol.-Reg. Stud., 34. 100766. Open access


Study region

Nine first-class rivers on the north-eastern Japanese Pacific Ocean coast.

Study focus

This study shows new confirmative data that the Cell Distributed Runoff Model version 3.1.1 (CDRM) calibrated by the Shuffled Complex Evolution optimization method developed at the University of Arizona (SCE-UA) can accurately forecast real-time river discharges induced by extreme typhoon Hagibis. Furthermore, we discuss reasons for the equifinality of three calibrated parameter sets, relative importance of typhoon features for calibration and quantify the relationship of distances between the trajectories of three typhoons and associated river basins.

New hydrological insights

As a result of climate change impacts, record-breaking disasters with unprecedented heavy rainfalls, typhoon intensities and associated extreme river discharges are increasing, making it important to develop the real-time forecasting tools for extreme river discharges during floods. The CDRM accurately projected river mouth discharges from three Japanese typhoons (Hagibis-2019, Roke-2011 and Chataan-2002) using calibrated parameter sets from each typhoon. We found the equifinality issue among the calibrated parameter sets but they showed satisfactory cross-validation results with respect to river mouth hydrographs; that similar typhoon trajectories were more important for calibration than rainfall intensities and central pressures; that this methodology was accurate for typhoons passing within distances lower than 130 km from associated river basins. These findings contribute to developing the real-time forecasting tools for extreme river discharges during unprecedented heavy rainfall floods.