TSUNAMI PROPAGATION IN THE PACIFIC OCEAN

The Alaska tsunami of March 28, 1964, caused by a tectonic uplift, propagated across the Pacific Ocean and was even recorded at the shores of New Zealand and the Antarctica. The large distance propagation of this tsunami is investigated by a numerical model based on the shallow water equations. The model includes bottom friction, eddy viscosity and Coriolis acceleration and yields the water elevation and the vertically integrated current velocity. The generation mechanism is given by a simplified initial condition, that is derived from the observed average uplift of 1.8 m for an area of 110000 km on the Continental Shelf. The computed tsunami propagation is presented by means of the first wave travel time and height on Pacific Ocean maps and by giving sea surface time series for selected stations. These computed results are compared with observations, especially considering the limitations of the model due to the coarse grid net having been used.