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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.
The picture above shows how the shape of a tsunami wave changes as it moves into shallower water.
Click on image for full size

What Is a Tsunami?

Tsunami waves are made in an ocean or other body of water by an earthquake, landslide, volcanic eruption, or meteorite impact. Tsunamis can cause huge destruction when they hit coastlines. Some people call tsunamis “tidal waves”, but these large waves really have little to do with tides, so the term “tidal wave” does not really suit them.

Tsunami waves are different from the waves you can usually find rolling into the coast of a lake or ocean. Those waves are made by wind offshore and are quite small compared with tsunami waves. Tsunami waves are huge and can travel very quickly, but they are only about one meter high in the open ocean.

As a tsunami wave travels into shallower water near the coast, it slows and grows in height. When it finally reaches the coast, a tsunami may have a height of as much as 30 meters and move much faster than a person can run. A few minutes before a tsunami wave hits, the water near shore may move away, exposing the ocean floor.

A tsunami can cause erosion at the shore and flooding inland. The water moves with such force that it is capable of crushing homes and other buildings.

Last modified May 21, 2008 by Lisa Gardiner.

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Our online store includes issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, as well as books on science education!

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF