What are tsunamis?

Tsunamis are giant waves caused by earthquakes, volcanic eruptions, landslides, and falling space rocks called meteorites. Tsunamis can travel in all directions as fast as 450 miles per hour with waves as high as 100 feet at the shore. Strong currents and riptides from a tsunami can be dangerous as they can pull you and other objects into the ocean. The areas most affected by tsunamis are coastal areas in countries around the Pacific Ocean. Hawaii is the U.S. state most at risk and has an average of one tsunami every year. Alaska is also at significant risk, especially if an earthquake triggers a tsunami.

Deadliest in World History

The deadliest tsunami was the Boxing Day tsunami in 2004 in Indonesia. An earthquake caused a tsunami and created giant waves 20 minutes after the earthquake occurred. Over 230,000 people died as a result.

Deadliest in U.S. History

The deadliest tsunami in United States history occurred in 1964 on the West Coast. Caused by an earthquake that measured 9.2 on the Richter scale, waves reached heights of 150 feet, killing over 139 people and causing $17 million in property damage.

How to Prepare

Before a tsunami, be aware of the water. Get out of the area if the ground begins shaking, you hear a loud ocean roar, or the water recedes so far that you can see the ocean floor.

During a tsunami, get as far away from the ocean as possible. Do not go to the beach to look at the tsunami. People cannot outrun a wave.

After a tsunami, do not leave your home until officials say it is safe. Stay away from buildings with water around them because buildings can collapse. Stay away from debris in the water, including garbage, wood, plastic, or metal.

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