Since 2004 Indian Ocean tsunami, the potential tsunami hazard from Manila trench has been highlighted of concerns by the countries surrounding the South China Sea. In this paper, we focus on the impact of potential tsunami hazard on southern China based on numerical method as well as theoretical analysis. A tsunami scenario induced by a hypothetical earthquake in the Manila Trench is simulated by using a finite-difference model based on nonlinear shallow-water equations. It is found that southern China is possible to be severely affected by tsunami waves. The coastal regions of southern China can be attacked in 2.5~4 hours after the deformation of the plate. For the hypothetical case of Mw 9.0 earthquake, the maximum surface elevation will reach 300cm and the current speed can reach several m/s. Considering the local tsunami amplification over the shelf-break and shelf, the results could be more disastrous. Further research and monitoring of the tsunamis in this area are urgent and necessary.
As one of the most devastating natural disasters faced by human beings, tsunami has been paid more and more attention and researches in recent years, especially after the devastating Indian Ocean tsunami in 2004. A tsunami is a very long-wavelength wave of water that is generated by sudden displacement of the sea floor or disruption of any body of standing water (Helal and Mehanna, 2008). It can be triggered by various sources like submarine earthquakes, submarine landslides, volcano eruptions, and even nuclear explosions or asteroid impacts (Satake and Atwater, 2007). Most tsunamis are generated by shallow large earthquakes in subduction zones (Satake and Tanioka, 1999). Generally speaking, hazardous tsunamigenic earthquakes have three characteristics in common: first, the water depth at the source region is deep and the topography varies sharply;