Tsunami
The term "tsunami" is a borrowingfrom the Japanese tsunami 津波, meaning "harbour wave." For the plural, one can either follow ordinary English practice and add an s, or use an invariable plural as

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While Japan may have the longest recorded history of tsunamis, the sheer destruction caused by the 2004 Indian Ocean earthquake and tsunamievent mark it as the most devastating

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The principal generation mechanism of a tsunami is the displacement of a substantial volume of water or perturbation of the sea. This displacement of water is usually caused

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Tsunamis are caused by earthquakes, landslides, volcanic explosions, glacier calvings, and bolides. They cause damage by two mechanisms: the smashing force of a wall of water

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As with earthquakes, several attempts have been made to set up scales of tsunami intensity or magnitude to allow comparison between different events.
Intensity scales
The first scales used routinely to measure the intensity of tsunamis

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Several terms are used to describe the different characteristics of tsunami in terms of their height:
• Amplitude, Wave Height, or Tsunami Height: Refers to the height of a tsunami relative to the normal sea level at the time of the tsunami, which may

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All waveshave a positive and negative peak; that is, a ridge and a trough. In the case of a propagating wave like a tsunami, either may be the first to arrive. If the first part to arrive at the shore is the ridge, a massive breaking wave or sudden flooding will be the first effect

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