Abstract
Tsunami source of the 2011 off the Pacific coast of Tohoku Earthquake reached into head of Tokyo Bay. The observed wave height at head of Tokyo Bay was greater than at mouth of it. The increase of wave height couldn't elucidated by the oscillation characteristics of long wave in the bay has been already clarified. We investigate behavior of long waves at head of the bay by 2D nonlinear shallow-water equation with the quadtree grid system to describe geometry of ports. This study reveals that local scale topography plays an important role in the oscillation characteristics of long waves at head of a bay. Since there are so many population, property and many connecting rivers at head of the bay, this study is an important knowledge for disaster mitigation.
