Author(s): Han Soo Lee; Tomohisa Shimoyama
Linked Author(s): Han Soo Lee
Keywords: Tsunami; Tide; The Seto Inland Sea; Adaptive mesh refinement; Nankai trough; Tokai-Tonankai-Nankai earthquake
Abstract: This paper investigates the impacts of tidal currents on extreme tsunami propagation in the Seto Inland Sea, Japan, based on numerical experiments. Tsunami experiments are conducted based on five scenarios taking the tidal currents at 4 different phases, such as high, ebb, low, and flood tide, into account. The initial tsunami displacement is adopted from the first case scenario announced by the National Disaster Prevention Council of Japan for the potential extreme tsunami due to Tokai-Tonankai-Nankai linked earthquake along the Nankai Trough. Based on the results of numerical experiments, the maximum tsunami heights at almost all probes in and out of the Seto Inland Sea are reduced after considering the tidal currents. The probes in the Bungo and Kii Channel show less significant effects of tidal currents on tsunami propagation. However, the probes in the Seto Inland Sea where the tide ranges are large compared to those out of the sea depict large difference in the maximum tsunami heights and in the arrival time of the first waves. For instance, the maximum tsunami height calculated at Shimonoseki-Oki differs nearly by 1 m after taking the tidal currents into account. The arrival times of the first waves in the Seto Inland Sea are faster during the flood tide over which the tsunamis are propagating.
Year: 2013