¿What Is A Tsunami?

.A tsunami (plural: tsunamis or tsunami; from Japanese: 津波, lit. "harbor wave"English pronunciation: /suːˈnɑːmi/ soo-nah-mee or /tsuːˈnɑːmi/ tsoo-nah-mee is a series of water wavescaused by the displacement of a large volume of a body of water, typically an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions (including detonationsof underwater nuclear devices), landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami.
Tsunami wavesdo not resemble normal sea waves, because their wavelength is far longer. Rather than appearing as a breaking wave, a tsunami may instead initially resemble a rapidly rising tide, andfor this reason they are often referred to as tidal waves. Tsunamis generally consist of a series of waves with periods ranging from minutes to hours, arriving in a so-called "wavetrain".[4] Wave heights of tens of metres can be generated by large events. Although the impact of tsunamis is limited to coastal areas, their destructive power can be enormous and they canaffect entire ocean basins; the 2004 Indian Ocean tsunami was among the deadliest natural disasters in human history with over 230,000 people killed in 14 countries bordering the IndianOcean. The Greek historian Thucydides suggested in 426 B.C. that tsunamis were related to submarine earthquakes, but the understanding of a tsunami's nature remained slim until the20th century and much remains unknown. Major areas of current research include trying to determine why some large earthquakes do not generate tsunamis while other smaller ones do; tryingto accurately forecast the passage of tsunamis across the oceans; and also to forecast how tsunami waves would interact with specific shorelines.

http://en.wikipedia.org/wiki/Tsunami