The distance a tsunami can travel inland varies widely depending on factors such as wave height, coastal topography, ocean depth, and land features.
- Typical distances: Small tsunamis may travel several hundred meters to about 1 kilometer inland. Moderate tsunamis with wave heights of 10-20 feet can inundate areas up to 2-3 kilometers (about 1.2-1.9 miles) inland, especially in flat coastal regions
- Large tsunamis: Massive waves over 30 feet high can penetrate several kilometers inland. For example, the 2004 Indian Ocean tsunami reached up to 3 kilometers inland in some areas, and the 2011 TÅhoku tsunami in Japan traveled several miles inland, devastating coastal cities
- Low-lying coastal areas: In regions less than 10 meters above sea level, tsunamis can penetrate several kilometers inland, with some historical records showing tsunamis reaching tens of kilometers inland and flooding areas tens of meters above sea level
- Extreme cases: Mega-tsunamis generated by rare events like asteroid impacts could produce waves thousands of feet high, but the inland penetration depends on many variables including wave energy, velocity, and landscape. For instance, an asteroid impact in the Gulf of Mexico might have caused a megatsunami reaching inland as far as northern Tennessee, but such waves lose momentum quickly when encountering land obstacles
- General maximum inland reach: Tsunamis can surge up to about 10 miles (16 kilometers) inland in extreme cases, though most commonly the inundation is within a few kilometers from the shore
In summary, while small tsunamis typically travel less than 1 km inland, large and catastrophic tsunamis can penetrate several kilometers to over 10 kilometers inland depending on local geography and wave size
