earthquake

On December 26, 2004 a great underwater earthquake near the coast of Indonesia caused the greatest tsunami in history. 280,000 people died and many coastal villages were wiped out.

The word tsunami comes from the Japanese : tsu means harbour and nami waves. A tsunami is a series of ocean waves that can travel over hundreds of kilometres at a very high speed. They are hardly seen in the open ocean, but when they reach the shallow water near the coast they get taller and taller—up to 30 metres. The waves are so powerful that they can destroy everything that gets in their way.

Tsunamis are created by earthquakes on the ocean floor. The earth’s crust is made up of manyplates that always move. Where such plates meet one of them may move on top of the other. When a plate moves upward it pushes the water above normal sea level. That is when a tsunami is born.