Nonlinear processes in tsunami simulations for the Peruvian coast with a focus on Lima/Callao

Abstract

Numerical simulations of the tsunami inundation processes require a highly nonlinear scheme. The main inundation properties, such as theflow depth and velocity depend critically on topographical imprints and bottom friction parameters. Here, we investigate the tsunami inundation in Lima and Callao resulting from the extensive 1746 (Mw 9.0) earthquake that ruptured along the Peruvian coast.Two numerical tsunami codes have been used in this analysis based on shallow water equations. We determine the relative importance of different parts in these equations with a focus on nonlinear terms. Particular focus is put on the momentum advection, bottom friction, and volume conservation in different mesh (triangular meshes and nested grids). We determine the influence on large-scale quantities like inundation extent and volume, flow velocities, and small-scale fluctuations. In that respect, also sensitivities regarding the bottom friction parameters are investigated.