Author(s): Hongwei Liu; Mohamed S. Ghidaoui
Linked Author(s): Mohamed S. Ghidaoui
Keywords: No Keywords
Abstract: Recently, post-tsunami field observations as well as experimental and numerical studies suggest that coral reefs provide significant costal protection against tsunami waves. It is also believed that the man-made or natural gaps in a coral reef create funnels for the tsunami energy, resulting in significantly enhanced wave heights and water inundations as well as greater run-up there. In this paper, the effects of coral reefs on coastal wave propagation are numerically investigated by solving the nonlinear shallow water equations. First, we study the tsunami run-up on onedimensional idealized topographies. The 1-D numerical simulations focus on the investigation of the influence of reef depth, width and roughness as well as wave amplitude and length on wave run-up. The numerical predictions are consistent with those in the literature and show that coral reefs may provide effective shoreline protection against tsunami waves. Second, we present the two-dimensional model simulations of the solitary waves passing through a coral reef with a gap. The numerical results support the notion that the destruction in the near region behind the reef gap is more serious than that in other regions behind healthy reefs, thus reducing both global and local demolition to coral reefs can help protect coastal assets and ecosystems.