Ocean Analysis by Tsunami Simulation of the Nankai Trough Massive Earthquake

Large-scale tsunamis have a major impact on the natural environment. Therefore, it is important to predict a large-scale tsunami. Recently, large-scale tsunami simulation using a supercomputer has been performed for prediction. By analyzing large-scale tsunami simulation data obtained from the supercomputer, it is expected that damage will be minimized. The purpose of this paper is to propose a visualization method for analysis support of simulation results. There are three kinds of visualization methods proposed. The first method is simultaneous visualization of a majority of feature quantities based on an opacity transfer function obtained by extending the HSV color space. This is aimed at observing the mutual relationship between feature quantities obtained by simulation. The second method is to create volume data in which time-series images are superimposed in the time axis direction (XYT space time) and to visualize the time-series data. This is aimed at a detailed analysis of the full-time behavior and specific feature quantities. The third method is to visualize the fusion of the cross-section plane of a tsunami and the fluid volume around it. This is aimed at the detailed visualization of the observation data in the sea, and by fusing the surrounding data, the detailed time-dependent flow velocity and salinity in the sea can be clearly observed. This paper presents the results of visualizing these three methods by applying them to the flow velocity and salinity data obtained from the simulation of the Nankai Trough massive earthquake and analyze these data.