Tsunamis

A tsunami is a very big ocean wave. Tsunamis are not like normal waves from the wind. They are caused by something big moving the water, like an earthquake under the sea. Tsunamis can travel very fast across the ocean.

What Causes a Tsunami

Most tsunamis start with an earthquake on the ocean floor. The shaking pushes a huge amount of water up. That water moves out in big waves. Tsunamis can also be caused by volcanoes or big landslides into the sea.

What Happens on Shore

Out in the deep ocean, a tsunami may not look very tall. But when it gets to shallow water near land, it grows much bigger. It can crash onto the shore and flood towns. Sometimes the water pulls back from the beach before a tsunami hits, which is a warning sign.

Fun Facts

• The word tsunami comes from Japan and means harbor wave.
• A tsunami can travel as fast as a jet plane.
• Tsunami waves can be more than 100 feet tall when they hit land.

Did You Know?

Scientists have placed special buoys in the oceans to help warn people when a tsunami is coming.