Recent Developments in Tsunami Hazard Mitigation

Abstract

Tsunamis are a series of ocean waves generated by abrupt, large disturbances of the ocean surface such as earthquakes, volcanic eruptions, landslides, slumps, and meteor impacts. These waves can engulf a coastal community within minutes of their birth and cause loss of life, catastrophic destruction to structures and infrastructure, and severe erosion of the shoreline by hours of repeated attack of waves many minutes apart (Figure 1). Human suffering during tsunami flooding can be enormous: people are swept along with other debris in the tsunami-induced currents at speeds up to 60 km/hr, resulting in drowning due to multiple injuries like broken bones, lacerations, abrasions, punctures, and crushed body cavities. Following the hours of tsunami attack, survivors may suffer from exposure to the environment; untreated shock may lead to gangrene, exacerbating the injuries and leading to more deaths. Since 1850, tsunamis in the Pacific have caused the death of over 120,000 coastal residents. Tsunamis are a major hazard to coastal residents in earthquake-prone regions (Table 1).