Tsunami Facts

1. A tsunami is a series of sea waves caused by an underwater earthquake, landslide, or volcanic 

eruption. More rarely, a tsunami can be generated by a giant meteor impact with the ocean.

2. The 2004 Indian Ocean tsunami could rank as the most devastating on record. More than 

200,000 people lost their lives, many of them washed out to sea.

3. Tsunami is as fast as commercial Jet. Where the ocean is deep, tsunamis can travel unnoticed 

on the surface at speeds up to 500 miles an hour (800 kilometers an hour)

4.In 2004, the Indian Ocean tsunami was caused by an earthquake that is thought to have had the 

energy of 23,000 atomic bombs. Within hours of the earthquake in 2004, killer waves radiating 

from the epicenter slammed into the coastline of 11 countries, damaging countries from east Africa 

to Thailand. By the end of the day, the tsunami had already killed 150,000 people. The final death 

toll was 283,000. 

5.Scientists can accurately estimate the time when a tsunami will arrive almost anywhere around 

the world based on calculations using the depth of the water, distances from one place to another, 

and the time that the earthquake or other event occurred.

6.Tsunami waves can be as long as 60 miles and be as far as an hour apart. These waves can cross 

entire oceans without losing much energy.

7. Once a tsunami reaches the shallow water near the coast, it slows down. The top of the wave 

moves faster than the bottom, causing the sea to rise dramatically, as much as 100 feet at times. 

8.When the ocean is deep, tsunamis may be less than a foot high on the ocean’s surface, can travel 

at speeds up to 500 mph without being noticed and cross the entire ocean in less than a day. 

9.A tsunami is not just one wave but a series of waves or a “wave train.”