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A simple parameterization of the loading deformation of the seafloor is incorporated into a tsunami simulation model in order to realistically calculate tsunami travel time, especially at regions far from the source. The parameterization uses one scalar parameter that is optimized effectively by far-field, deep-sea records of recent giant tsunamis: the 2011 Tohoku and the 2010 Chilean tsunamis. Using this parameterization with the optimal values, the observed tsunamis are realistically simulated in both near and far fields. The optimal values seem equivalent for both giant tsunamis, and are relatively smaller than those previously verified for ocean tide modeling, which is reasonable because of the shorter wavelengths of tsunamis.

The tsunami generated by the Great East Japan Earthquake caused serious damage to the coastal areas of the Tohoku district. Numerical simulations are used to predict damage caused by tsunamis. Shallow-water equations are generally used in numerical simulations of tsunami propagation from the open sea to the coast. This research focuses on viscous shallow-water equations and attempts to generate a computational method using finite element techniques based on the previous investigations of Kanayama and Ohtsuka (Coast Eng Jpn 21:157–171, 1978). First, the viscous shallow-water equation system is derived from the Navier–Stokes equations, based on the assumption of hydrostatic pressure in the direction of gravity. Next a numerical scheme is shown. Finally, tsunami simulations of Hakata Bay and Tohoku-Oki are shown using the approach.

The present paper gives a numerical simulation of tsunami propagation in the ocean with a real bathymetry. The computed displacement of the water surface in the generation area for a typical seismic source (Alexeev, Gusiakov /1/) is used to specify initial conditions for computing the propagation of a tsunami near the Kuril Islands. The nonlinear long-wave equations are adopted as a description of tsunami behavior and solved numerically by a finite-difference method. The wave field of tsunami and mareograms at the shore line are found. The comparison of the results with those for linear model of the tsunami propagation is carried out.

Taking the 2011 Tohoku earthquake as an example, we demonstrate the ability of real-time GPS to provide qualified tsunami early warning within minutes. While in earlier studies we demonstrated the power of the so-called GPS shield concept based on synthetic data, we here present a complete processing chain starting from actual GPS raw data and fully simulate the situation as it would be in a warning center. The procedure includes processing of GPS observations with predicted high precision orbits, inversion for slip and computation of the tsunami propagation and coastal warning levels. We show that in case of the Tohoku earthquake, it would be feasible to provide accurate tsunami warning as soon as 3 min after the beginning of the earthquake.

Se propone un método unidimensional simplificado para estimar la altura del frente de onda de tsunamis transoceánicosmediante una función de direccionalidad de flujo de energía aplicada a un modelo unidimensional en diferencias finitas basado enlas ecuaciones de aguas someras. La simulación numérica del tsunami de Shikotan del 4 de octubre de 1994 y el análisis de lasobservaciones, obtenidas en mar abierto a ~6300 km de su origen, así como el análisis de las ecuaciones lineales de aguas somerasy de las ecuaciones lineales de Boussinesq, muestran que la dispersión por frecuencia prescrita por las ecuaciones de Boussinesqes un mecanismo necesario y suficiente para simular la propagación de tsunamis transoceánicos grandes y medianos. La soluciónanalítica de las ecuaciones no dispersivas de aguas someras sobrestima significantemente la altura del frente de onda del tsunamien comparación con la solución analítica obtenida de las ecuaciones dispersivas de Boussinesq. Los resultados confirman que elmétodo explícito de diferencias finitas centrales aplicado a las ecuaciones de aguas someras es apropiado para simular la propagacióntransoceánica de tsunamis. Esto se debe a que la dispersión intrínseca del método numérico es similar a la dispersión por frecuenciaprescrita por Boussinesq (Imamura et al.,1990; Liu et al., 1995).

During the 2009 Samoan Islands Tsunami, the wide coral reef platform in front of the islands affected the approaching tsunami behavior. This research aims to understand the characteristics of a tsunami propagating over a reef platform by using a turbulence model. A Large Eddy Simulation (LES) model was used to simulate wave breaking and energy dissipation. The results of numerical simulations by using LES model were shown to reproduce well the results of the field survey in the 2009 Samoan Islands Tsunami. The present method may also apply to other countries which have coral reefs and contribute to regional tsunami mitigation strategies. It is important to understand what is the phenomenon that people in coastal areas actually experience as well as the height and arrival time of a tsunami.

Advances in computer programming have permitted researchers to predict and visualize how tsunami waves affect coastline areas. Although it’s possible to use numerical model simulations to predict the inundation of tsunamis, the process has some limitations. In order to solve the Boussinesq-type equations for tsunami propagation in the near-shore, it typically requires hundreds of hours of computation time and/or multiple CPUs. (Tavakkol and Lynett, 2017). Recently the University of Southern California developed a numerical model called Celeris, which can solve the Boussinesq-type equations faster than real time. The numerical model can run with minimum preparations on an average-user laptop and is able to provide results of wave inundation in a matter of seconds (Tavakkol and Lynett, 2017). The purpose of this research is to validate the results of wave inundation provided by Celeris and to study how reefs affect the inundation in the shoreline. If Celeris is validated, it could be used to study how to reduce the impact of tsunamis in the coast, explore the possibilities of using reefs to dissipate the energy of waves, improve evacuation routes, etc.

Tsunami increases its height on the shallow water area and may transfers into bore when it breaks. Bore type tsunami sometimes produces huge forces and causes large damages on coastal infrastructures. In order to mitigate tsunami damages, bore type tsunami propagation, run-up and its characteristics need to be understood. And aside of experimental study, numerical simulation provides principal physical quantities with higher resolution in time and space. This study discus the validity of a numerical simulation based on VOF method, CADMAS-SURF, and characteristics of bore propagation on to a dike.

The International Symposium on Tsunamis and Tsunami Research was held in Honolulu, Hawaii, October 7–10, 1969. Australia, Canada, Germany, Japan, New Zealand, USSR, and the United States sent representatives. There were three seminars: (1) Seismic Source and Energy Transfer, convened by S. Soloviev; (2) Tsunami Instrumentation, convened by Vitousek; and (3) Tsunami Propagation of Runup, convened by K. Kajiura.

Initially, this study arose from questions concerning the scattering of tsunamis as they propagate over the irregular topography of the deep waters of the ocean. The mathematical problem to which this led is pertinent to many other phenomena, however, and we direct the analysis, here, to the propagation of gravity waves over an irregular bottom topography and to the lateral oscillations of an elastic string whose ends undergo random longitudinal displacements. Several facets of the mathematical problem are rather fascinating but the results do suggest that scattering is not the most important part of the tsunami propagation.