Tsunamis

By: Reagan Bustabad

How are Tsunamis created?

  • A tsunami is caused by a rearrangement of water in the ocean.
  • It can be a reaction of many things including landslides, earthquakes, volcanic eruptions, glaciers, and meteorites.
  • One of the main causes are earthquakes, because when plates move they can cause holes in the earth's crust. Water can enter this hole, and this can cause a rearrangement of water.
  • When the rearrangement of water is put forth the water ripples to the surface
  • The waves can travel for immense distances and grow up to 100 feet high!

Why are Tsunamis Harmful?

  • When tsunamis reach the shore they can cause great damage
  • Houses, trees, buildings, cars, and much more become demolished as these waves rush onto the shore.
  • Tsunamis are extremely hard to predict, and hard to know when one is being formed.
  • This means some areas do not get much time to evacuate or prepare for one.
  • Many people have been killed due to tsunamis

Where do Tsunamis Occur?

  • Tsunamis usually occur in the Pacific Ocean (more towards Indonesia).
  • Near here there are a lot of submarine earthquakes which cause the tsunamis.
  • Most of the tsunamis on American soil have been near California, Hawaii, and Alaska.
  • Tsunamis can also occur in the Mediterranean Sea and the Caribbean Sea as well.

How are Tsunamis Measured?

  • Tsunamis can be measured by tide gauges, satellites, and the DART system.
  • Tide gauges are used to measure tide levels which help in predicting where a tsunami has or is likely to form.
  • The height of the ocean surface can be measured with electromagnetic waves. This is how satellites are collected.
  • The Deep-ocean Assessment and Reporting of Tsunamis, or DART, system uses sea-bottom recorders and buoys to inform employees when a tsunami is being formed.
  • Also, a Richter Scale can be used if the tsunami was caused by an earthquake.

What are the Largest Tsunamis Recorded?

  • On July 9, 1958 about 30.6 million cubic meters of land was moved by an earthquake along the Fairweather Fault in the Alaska Panhandle.
  • Rocks came down into the ocean, creating a tsunami.
  • The wave crashed into the Gilbert inlet and continued all the way down Lituya Bay.
  • All trees and plants were swept up by the 1720 feet tall wave, the highest tsunami ever recorded.
  • Only five people died, and there were only four survivors.
  • The area the tsunami hit was fortunately not populated.


  • On August 26, 1883 Volcano Krakatoa in Indonesia erupted, causing a tsunami.
  • This tsunami grew to be up 120 feet in height.
  • Over 36,000 people died, 90% of them by the tsunami.
  • The tsunami destroyed 165 villages in Sumatra and Java.

How do I Prepare for a Tsunami?

  • Make a evacuation plan for all the places you might be located if a tsunami occurs.
  • Share the evacuation plan with family, friends, and associates.
  • Create a disaster supplies kit to take with you if a tsunami occurs.
  • Have a radio handy to listen for any severe weather updates or warnings.