Numerical simulation of tsunamis — Its present and near future

Hindcasting of a tsunami by numerical simulations is a process of lengthy and complicated deductions, knowing only the final results such as run-up heights and tide records, both of which are possibly biased due to an insufficient number of records and due to hydraulic and mechanical limitation of tide gauges. There are many sources of error. The initial profile, determined with seismic data, can even be different from the actual tsunami profile. The numerical scheme introduces errors. Nonlinearity near and on land requires an appropriate selection of equations. Taking these facts into account, it should be noted that numerical simulations produce satisfactory information for practical use, because the final error is usually within 15% as far as the maximum run-up height is concerned.The state-of-the-art of tsunami numerical simulations is critically summarized from generation to run-up. Problems in the near future are also stated. Fruitful application of computer graphics is suggested.