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Preparing for Tsunamis The Anatomy of a Tsunami Warning Signs of a Tsunami
What To Do When a Tsunami Occurs

The Dangers of a Tsunami

 

Anyone expecting to travel to, or live by the Pacific Ocean must be aware of the effects of tsunamis. Education in the characteristics of tsunamis, as well as the disastrous results when these ocean waves come ashore, will increase chances of survival.

 

A tsunami is a wave series that speeds over the open ocean at very high speeds, up to six hundred miles per hour, before making landfall. Tsunamis are created by earthquakes and volcanoes, and take their name from the Japanese. Translated to English, it is "harbor wave". A tsunami is actually a ripple effect, much like dropping a stone into water and seeing the waves travel out from the source in all directions. They are hundreds of miles long, have a relatively low profile, and are virtually undetected by passing ships.

 

When the waves get closer to a land mass, they slow down to approximately thirty-five miles per hour, and grow taller in height as the waves climb up with the rise of the ocean floor. If the rise of the seafloor is steep, the wave will be dramatic in height. The approach can be seen as changes between high and low water levels at the shore, in intervals of ten to forty-five minutes. A local tsunami can have effect in less than ten minutes, which is not enough time to issue a warning.

 

Major earthquakes have given reason to suspect the generation of tsunami, and the following would be issued:

  • Tsunami information bulletin = a threat exists.
  • Tsunami watch = residents should be alert.
  • Tsunami warning = tsunami arrival times are given

Those at risk would be within one mile of the coast and less than 25 feet above sea level. A tsunami will arrive as a series of waves, so there is danger even after the arrival of the first wave. They also "wrap around" an island, carrying debris as they go, and the waves can vary in their intensity, with the following waves causing more havoc that the first.

 

To survive a tsunami event, please pay attention to the following:

 

  • If you feel an earthquake, expect a tsunami warning in its wake, and vacate low-lying areas.
  • If you see a drop in sea level; leave the area immediately. Also, a tsunami may sound like an oncoming train.
  • A tsunami can also be dangerous farther from shore because it can carry buildings, cars, and boulders as it travels. 
  • Do not go to the shore after a warning has issued to go on a tsunami "hunt". You may not be able to get away quickly: If you can see it, you will not be able to outrun it.
  • Do not mix a tsunami with sports. A tsunami cannot be surfed; the wave does not curl and break for surfing.
  • Most deaths occur from drowning. Being wary of any abnormalities due to earthquake activity will help you survive a disaster caused by a tsunami.
Preparing for Tsunamis The Anatomy of a Tsunami Warning Signs of a Tsunami
Preparing for Tsunamis
 

Tsunamis are a series of large waves breaking over the coastal regions.  They can occur almost without warning and cause floods and damage to coastal communities.  Fortunately, they rarely occur.  Storm surges occur more frequently.  Residents, particularly those living in coastal lowlands, should take precautions against this natural phenomenon. 

 

Quick Facts on Tsunamis
  • Tsunamis are a series of large waves caused by events such as underwater earthquakes, landslides, volcanic eruptions, and less frequently, meteor impacts.  Tsunamis can also occur in large lakes.
  • They can occur practically without warning in oceans and large lakes.
  • A tsunami may be caused by a large high energy but relatively short-lived disturbance in the ocean floor.  Tsunami waves can travel the ocean at speeds of 500 mph, comparable to the speed of a jet plane.
  • As tsunami waves approach the shore, both their depth and speed decrease but their height increases as their length decreases.  In twenty meters of water, these waves can reach speeds of 30mph.
  • Tsunamis occur when waves follow one another with a lag period of between a few minutes to several hours.
  • Tsunami waves can reach heights upwards of sixty meters; this is the equivalent of a ten-story building.
How To Prepare For A Tsunami
  • Examine your home and surrounding land to determine whether flooding is likely.  Identify any vulnerable points and take corrective actions.
  • Know how to turn off the gas and electricity sources in your home.  It may be the case that authorities will ask you to do so.
  • Don’t leave your important documents (or other valuable) in the basement.  Keep them in upper floors, which will protect them from flooding. 
  • Ensure that your family has both an emergency kit and emergency plan.
  • Ensure that your emergency kit is easily transported in a duffel bag or small rolling suitcase.
  • Your local Red Cross chapter can teach you basic first aid skills and CPR.  There, you can also learn water survival skills by taking swimming and boating navigation lessons.
If you have question or wish to learn more about evacuation procedures in your area, contact the emergency services, police or fire department local to your region.
 

The Anatomy of a Tsunami

Anyone expecting to travel to, or live by the Pacific Ocean must be aware of the effects of tsunamis. Education in the characteristics of tsunamis, as well as the disastrous results when these ocean waves come ashore, will increase chances of survival.

A tsunami is a wave series that speeds over the open ocean at very high speeds, up to six hundred miles per hour, before making landfall. Tsunamis are created by earthquakes and volcanoes, and take their name from the Japanese. Translated to English, it is "harbor wave". A tsunami is actually a ripple effect, much like dropping a stone into water and seeing the waves travel out from the source in all directions. They are hundreds of miles long, have a relatively low profile, and are virtually undetected by passing ships.

When the waves get closer to a land mass, they slow down to approximately thirty-five miles per hour, and grow taller in height as the waves climb up with the rise of the ocean floor. If the rise of the seafloor is steep, the wave will be dramatic in height. The approach can be seen as changes between high and low water levels at the shore, in intervals of ten to forty-five minutes. A local tsunami can have effect in less than ten minutes, which is not enough time to issue a warning. This is a big reason why to stock up on emergency supplies just in case. Safety and security products along with shelter and sleeping back up are very important to keep in mind for your whole family. We recommend acquiring Mobile Emergency Preparedness Kit to be ready if a Tsunami hits. We recommend acquiring Mobile Emergency Preparedness Kit to be ready if a Tsunami hits.

Major earthquakes can cause a tsunami and in this case the following would be issued:

  • Tsunami information bulletin = a threat exists.
  • Tsunami watch = residents should be alert.
  • Tsunami warning = tsunami arrival times are given

Those at risk would be within one mile of the coast and less than 25 feet above sea level. A tsunami will arrive as a series of waves, so there is danger even after the arrival of the first wave. They also "wrap around" an island, carrying debris as they go, and the waves can vary in their intensity, with the following waves causing more havoc that the first. Educate yourself further on tsunamis by reading guides and teaching your family how to best stay safe during one.

To survive a tsunami event, please pay attention to the following:

  • If you feel an earthquake, expect a tsunami warning in its wake, and vacate low-lying areas.
  • If you see a drop in sea level; leave the area immediately. Also, a tsunami may sound like an oncoming train.
  • A tsunami can also be dangerous farther from shore because it can carry buildings, cars, and boulders as it travels.
  • Do not go to the shore after a warning has issued to go on a tsunami "hunt". You may not be able to get away quickly: If you can see it, you will not be able to outrun it.
  • Do not mix a tsunami with sports. A tsunami cannot be surfed; the wave does not curl and break for surfing.
  • Most deaths occur from drowning. Being wary of any abnormalities due to earthquake activity will help you survive a disaster caused by a tsunami. Know the disaster history of your environment and educate on how to protect yourself against them.

Recommended kits to prepare for a Tsunami:

Warning Signs of a Tsunami
  • A large-scale earthquake lasting for more than twenty seconds can be the precursor for a tsunami.  When a region is hit by an earthquake of large magnitude, you should be aware that coastal regions located near the earthquake’s epicenter could be hit by a tsunami.
  • A more immediate warning sign of a tsunami is the rapid and unexpected decline of water level, below what is normal during low tie.  This can happen for a few minutes before the coast is hit by a tsunami and is the only sign along coasts that are located too far away from the epicenter for the earthquake to be felt.
  • A tsunami can just as often occur without any warning signs.
  • The Seismological Society of America monitors these events at any time of day.  When a tsunami does occur, they try to give the earliest possible warning to the media in regions that are likely to be affected. 
  • The Communication and Traffic Services of the U.S. Coast Guard will also release maritime warnings in case of a tsunami.
  • When you become aware of a tsunami warning, seek higher ground if possible.  
What To Do When a Tsunami Occurs
What To Do When a Tsunami Occurs
  • Under no circumstance should you go near the coast to see the tsunami hit.  Remember this: if you can see it, than you are too close to escape.
  • If a tsunami is approaching and you cannot move to higher ground, stay indoors where you will be protected from the water.  It is preferable for you to find a space in the house away from any windows. 
  • Often, tsunamis are a series of waves that can be separated by a few minutes or even an hour.
  • Monitor the progress of the tsunami and be alert for any warnings or instructions from local authorities.  If you’re in a safe location when the tsunami strikes, stay there until local authorities indicate that the situation is under control.
  • After a tsunami, floodwater can accumulate and it can be dangerous to walk or drive through these waters.  Before driving, listen to instructions from local authorities that are coordinating the evacuation plans.
  • Be aware of risks such as hypothermia or drowning in the floodwaters.  Your local Red Cross chapter can provide more information on how to prevent these problems.