When a tsunami hits a coastline, it can cause great destruction and loss of life. Many tsunamis can be detected before they hit land, and the loss of life could be minimized with the use of modern technology.

The word tsunami comes from the Japanese word meaning "harbor wave." Tsunamis are sometimes incorrectly called "tidal waves" -- tsunamis are not caused by the tides (tides are caused by the gravitational force of the moon on the sea).

If you are on the beach and you see the water recede quickly and unexpectedly from the beach, run toward higher ground or inland -- there may be a tsunami coming. Also, if you are on the coast and there is an earthquake, there may be a tsunami, so run toward higher ground or inland. Many beaches have tsunami warning sirens -- do not ignore them.

You can make a tiny model of a tsunami by dropping a rock into a bowl of water, causing ripples to propagate (travel) outwards from the site of impact. Another way is to slightly jolt the bowl of water and watch it slosh over the rim on one side.