[20220204]IN11849_海啸：检测、预测和警告的背景和介绍.pdf

CRS INSIGHT Prepared for Members and Committees of Congress INSIGHTINSIGHTi i Tsunamis: Background and Introduction to Detection, Forecasts, and Warnings February 4, 2022 Background Tsunamis are a series of extremely long waves caused by a large and sudden displacement of water in a large waterbody, such as the ocean or an inland sea. That displacement can be caused by underwater earthquakes, landslides, or volcanic eruptions, certain types of weather, and impacts from celestial objects such as asteroids. Most tsunamis are the direct result of earthquakes or of landslides caused by earthquakes. Tsunamis radiate from the point of initial displacement and move across the waterbody. When tsunamis reach a coastline, they grow in wave height due to the shallowing waters, sometimes causing coastal and inland flooding, destruction of infrastructure, injuries, and fatalities. Certain coastal locations are especially vulnerable to tsunamis due to their proximity to tsunami sources, the depth and characteristics of the waterbody bottom, and the topography and elevation of land near the coast. Large displacements may cause tsunami impacts around the world; for example, the January 15, 2022, u