The Tsunami
by Nicholas S.

A tsunami is a series of ocean waves generated by under sea events, such as earthquakes, volcanic eruptions, or landslides. Tsunamis are also called tidal waves.

In the open ocean a tsunami could have a wave length of several hundred miles and travel at speeds up to 500 mph. However, the wave is usually less that 3 feet high. This size wave could pass unnoticed beneath a ship at sea.

When the tsunami approaches shallow water along the coast or shore, the wave slows down. The wave length gets shorter. But, the wave height could grow as high as 100 feet. When the wave hits the shore it could destroy buildings and drown people who couldn't escape.

A tsunami is not ranked by strength. Sometimes it is ranked by the height of the wave. Usually, the strength of the tsunami is measured by the earthquake that caused the wave. The earthquake must be at least 6.5 magnitude to cause a destructive tsunami.

The only real tsunami warning comes after a big earthquake is detected under water. Scientists know that a big earthquake could cause a tsunami to hit land that is close by. The U.S. does have a warning system, but many other countries in the world do not.

The worst tsunami in recent years happened in the Indian Ocean on December 26, 2004. This tsunami followed an earthquake that was 9.1 magnitude. This tsunami killed over 200,000 people and destroyed many homes and villages.

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