Best Strategies for Surviving
What is a Tsunami?
Tsunamis (pronounced soo-ná-mees), also known as seismic sea waves (mistakenly called “tidal waves”), are a series of enormous waves created by an underwater disturbance such as an earthquake, landslide, volcanic eruption, or meteorite. A tsunami can move over 500 hundreds of miles per hour in the
open ocean and smash into land with waves as high as 100 feet or more.
Tsunami Devastation--Leone, Samoa-2009
The term "tsunami" comes from the Japanese tsu (harbor) and nami (wave). Twenty-four tsunamis have caused damage in the United States and its territories during the last 204 years. The 2004 Indian Ocean tsunami killed over 200,000 people with many bodies washed out to see. Many people saw this occurrence on TV globally.
As a tsunami nears the coastline, it may begin to rise several feet or, in rare cases, tens of feet, and can cause great loss of life and property damage when it comes ashore. Tsunamis can travel upstream in coastal estuaries and rivers, with damaging waves extending farther inland than the immediate coast.
A tsunami can occur during any season of the year and at any time, day or night.
Feasibility of a Tsunami Occurrence for Your Location
Unless you live on a coastal area, you have nothing to be concerned about regarding tsunamis. However, tsunamis can generate huge waves deep into nearby coves and channels. A known instance of this occurred in Alaska.
Since tsunamis are caused by land earthquakes near coastal areas and by earthquakes under the ocean floor, it is not always known in the latter case when a tsunamis situation has occurred.
The good news is that today, scientists and governments have made great progress in placing earthquake monitors all over the world in the most critical areas of frequent occurrence. When under ocean earthquakes occur, tsunamis alerts are much more timely and accurate.
Tsunami Wave Swamping a Boat
Not all coastal or under ocean earthquakes generate tsunamis, but extreme caution and action should be undertaken by all potential areas of impact when alerts are generated. For, example, the recent Chile earthquake in February of 2010 created a tsunami that greatly damaged coastal towns in the Chilean coastline but did not generate enough wave power to reach Hawaii and Japan even though only scientist could detect their arrival.
All tsunamis are potentially dangerous, even though they may not damage every coastline they strike. The most destructive U.S. tsunamis have occurred along the coasts of California, Oregon, Washington, Alaska, and Hawaii which forms the eastern rim of the Ring of Fire.
What Typically Happens When a Tsunami Occurs?
From the area where the tsunami originates, waves travel outward in all directions. Once the wave approaches the shore, it builds in height. The
topography of the coastline and the ocean floor will influence the size of the wave. There may be more than one wave and the succeeding one may be
larger than the one before. That is why a small tsunami at one beach can be a giant wave a few miles away.
Earthquake-induced movement of the ocean floor most often generates tsunamis. If a major earthquake or landslide occurs close to shore, the first wave
in a series could reach the beach in a few minutes, even before a warning is issued. Areas are at greater risk if they are less than 25 feet above sea
level and within a mile of the shoreline.
Drowning is the most common cause of death associated with a tsunami. Tsunami waves and the receding water are very destructive to structures in the
run-up zone. Other hazards include flooding, contamination of drinking water, and fires from gas lines or ruptured tanks.
Surviving Tsunami Disasters--Steps to Take Before and After
The Alaska Tsunami Warning Center is responsible for tsunami warnings for California, Oregon, Washington, British Columbia, and Alaska.
The Pacific Tsunami Warning Center (PTWC) is responsible for providing warnings to international authorities, Hawaii, and U.S. territories within the
Pacific basin. The two Tsunami Warning Centers coordinate the information being disseminated.
Familiarize yourself with these terms to help identify a tsunami hazard:
An earthquake has occurred in the Pacific basin, which might generate a tsunami.
A tsunami was, or may have been generated, which could cause damage; therefore, people in the warned area are strongly advised to evacuate.
A tsunami was or may have been generated, but is at least two hours travel time to the area in Watch status.
If you live or are near a beach where tsunamis can occur:
- Turn on your radio to learn if there is a tsunami warning if an earthquake occurs and you are in a coastal area.
- Move inland to higher ground immediately and stay there.
- Stay away from the beach. Never go down to the beach to watch a tsunami come in. If you can see the wave you are too close to escape it.
- CAUTION- If there is noticeable recession in water away from the shoreline this is nature's tsunami warning and it should be heeded. You should move away immediately.
What to Do if You Feel a Strong Coastal Earthquake
If you feel an earthquake that lasts 20 seconds or longer when you are on the coast:
- Drop, cover, and hold on. You should first protect yourself from the earthquake.
- When the shaking stops, gather your family members and evacuate quickly. Leave everything else behind. A tsunami may be coming within minutes. Move quickly to higher ground away from the coast.
- Be careful to avoid downed power lines.
Stay away from buildings and bridges from which heavy objects might fall during an aftershock.
Steps to Take When a Tsunami WATCH Is Issued
Listen to a NOAA Weather Radio, Coast Guard frequency station, or other reliable source for updated emergency information.
As the energy of a tsunami is transferred through open water, it is not detectable. Seismic action may be the only advance warning before the tsunami aproaches the coastline.
Check your Disaster Supplies Kit. Some supplies may need to be replaced or restocked.
Locate family members and review evacuation plans. Make sure everyone knows there is a potential threat and the best way to safer ground.
If you have special evacuation needs (small children, elderly people, or persons with disabilities) consider early evacuation.
Evacuation may take longer, allow extra time.
If time permits, secure unanchored objects around your home or business. Tsunami waves can sweep away loose objects. Secure loose items or moving them inside will reduce potential loss or damage.
Be ready to evacuate. Being prepared will help you to move more quickly if a tsunami warning is issued.
What to Do When a Tsunami WARNING Is Issued
Listen to a NOAA Weather Radio, Coast Guard emergency frequency station, or other reliable source for updated emergency information. Authorities will issue a warning only if they believe there is a real threat from tsunami.
Follow instructions issued by local authorities. Recommended evacuation routes may be different from the one you use, or you may be advised to climb higher.
If you are in a tsunami risk area and you hear an official tsunami warning or detect signs of a Tsunami:
Evacuate at once. A tsunami warning is issued when authorities are certain that a tsunami threat exists, and there may be little time to get out
Take your Disaster Supplies Kit. Having supplies will make you more comfortable during the evacuation.
Get to higher ground as far inland as possible. Officials cannot reliably predict either the height or local effects of tsunamis.
Watching a tsunami from the beach or cliffs could put you in grave danger. If you can see the wave, you are too close to escape it.
Return home only after local officials tell you it is safe. A tsunami is a series of waves that may continue for hours. Do not assume that after one wave the danger is over. The next wave may be larger than the first one.
Actions to Take After Surviving a Tsunami Disaster.
The following are guidelines for the period following a tsunami:
Continue listening to a NOAA Weather Radio, Coast Guard emergency frequency station, or other reliable source for emergency information. The tsunami may have damaged roads, bridges, or other places that may be unsafe.
Help injured or trapped persons. Give first aid where appropriate. Call for help. Do not move seriously injured persons unless they are in immediate danger of further injury.
Help a neighbor who may require special assistance — infants, elderly people, and people with disabilities. Help a neighbor who may require special assistance — infants, elderly people, and people with disabilities.
Elderly people and people with disabilities may require additional assistance. People who care for them or who have large families may need additional
assistance in emergency situations.
Use the telephone only for emergency calls. Telephone lines are frequently overwhelmed in disaster situations. They need to be clear for emergency calls to get through.
Stay out of the building if waters remain around it. Tsunami waters, like flood waters, can undermine foundations, causing buildingsto sink, floors to crack, or walls to collapse.
When re-entering buildings or homes, use extreme caution. Tsunami-driven flood waters may have damaged buildings where you least expect it. Carefully watch every step you take.
Wear sturdy shoes. The most common injury following a disaster is cut feet.
Battery-powered lighting is the safest and easiest, preventing fire hazard for the user, occupants, and building.
Examine walls, floors, doors, staircases, and windows to make sure that the building is not in danger of collapsing.
Inspect foundations for cracks or other damage.
Cracks and damage to a foundation can render a building uninhabitable.
Look for fire hazards. There may be broken or leaking gas lines, flooded electrical circuits, or submerged furnaces or electrical appliances. Flammable or explosive
materials may come from upstream. Fire is the most frequent hazard following floods.
Check for gas leaks. If you smell gas or hear a blowing or hissing noise, open a window and quickly leave the building. Turn off the gas using the outside main valve if you
can, and call the gas company from a neighbor’s home. If you turn off the gas for any reason, it must be turned back on by a professional.
Look for electrical system damage. If you see sparks or broken or frayed wires, or if you smell burning insulation, turn off the electricity at the main fuse box or circuit breaker. If
you have to step in water to get to the fuse box or circuit breaker, call an electrician first for advice. Electrical equipment should be checked and
dried before being returned to service.
Check for sewage and water line damage.
If you suspect sewage lines are damaged, avoid using the toilets and call a plumber. If water pipes are damaged, contact the water company and avoid
using water from the tap. You can obtain safe water from undamaged water heaters or by melting ice cubes.
Only Use tap water if local health officials advise it is safe.
Watch out for animals, especially poisonous snakes, that may have come into buildings with the water. Use a stick to poke through debris. Tsunami flood waters flush snakes and animals out of their homes.
Watch for loose plaster, drywall, and ceilings that could fall.
Take pictures of the damage, both of the building and its contents, for insurance claims.
Open the windows and doors to help dry the building.
Shovel mud while it is still moist to give walls and floors an opportunity to dry.
Check food supplies. Any food that has come in contact with flood waters may be contaminated and should be thrown out.
Be Prepared for Looters—they will eventually come in nearly all societies. Be willing to protect yourself if you can.
Additional Resources for Surviving Tsunami Disasters:
For an excellent general and technical treatment of this subject see the information provided at this link--view original wikipedia article
Historical Notes Related to Surviving Tsunami Disasters:
As recent as February 2010, a tsunami was generated on the coast of Chile from a very large earthquake that occurred on the Chile mainland near the
ocean. It did emanate outward as far away as Russia and Japan, but the wave action was too small to be noticed except by scientific instruments.
American Red Cross: http://www.redcross.org/
Federal Emergency Management Agency (FEMA): http://www.fema.gov/
National Oceanic and Atmospheric Agency (NOAA) and their National Weather Service.
National Disaster Education Coalition:
American Red Cross, FEMA, IAEM, IBHS, NFPA, NWS, USDA/ CSREES, and USGS
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