Listen to this:
A tsunami (plural: tsunamis or tsunami; from Japanese: 津波, lit. “harbor wave”; English pronunciation: /tsuːˈnɑːmi/) , also known as a seismic sea wave, is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions (including detonations of underwater nuclear devices), landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami. Unlike normal ocean waves which are generated by wind or tides which are generated by the gravitational pull of the Moon and Sun, a tsunami is generated by the displacement of water.
I found great videos for the kids on YouTube (the challenge with teaching kids about tsunamis is that they are pretty devastating phenomena so I try to be careful about which videos I show them.
I also found this great illustration of how an earthquake triggers a tsunami on Wikipedia (Link).
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- Wikipedia entry for “Tsunami”
- Tsunami Facts for Kids from Science Kids
- Tsunamis from Geography for Kids