What You Should Do
- Tsunamis that strike coastal location in the Pacific Ocean Basin are
most always caused by earthquakes. These earthquakes might occur far away
or near where you live.
- Some tsunamis can be very large. In coastal areas their height can
be as great as 30 feet or more (100 feet in extreme cases), and they can
move inland several hundred feet.
- All low lying coastal areas can be struck by tsunamis.
- A tsunami consists of a series of waves. Often the first wave may not
be the largest. The danger from a tsunami can last for several hours after
the arrival of the first wave.
- Tsunamis can move faster than a person can run.
- Sometimes a tsunami causes the water near shore to recede, exposing
the ocean floor. The force of some tsunamis is enormous. Large rocks weighing
several tons along with boats and other debris can be moved inland hundreds
of feet by the tsunami wave activity. Homes and other buildings are destroyed.
All this material and water move with great force and can kill or injure
- Tsunamis can occur at any time, day or night.
- Tsunamis can travel up rivers and streams that lead to the ocean.
What You Should Do
Be aware of tsunami facts. This knowledge could save your life! Share
this knowledge with your relatives and friends. It could save their lives!
- If you are in school and you hear there is a tsunami warning, you should
follow the advice of teachers and other school personnel.
- If you are at home and hear there is a tsunami warning, you should
make sure you entire family is aware of the warning. Your family should
evacuate your house if you live in a tsunami evacuation. Move in an orderly,
calm and safe manner to the evacuation site or to any safe place outside
your evacuation zone. Follow the advice of local emergency and law enforcement
- If you are at the beach or near the ocean and you feel the earth shake,
move immediately to higher ground. DO NOT wait for a tsunami warning to
be announced. Stay away from rivers and streams that lead to the ocean
as you would stay away from the beach and ocean if there is a tsunami.
A regional tsunami from a local earthquake could strike some areas before
a tsunami warning could be announced.
- Tsunamis generated in distant locations will generally give people
enough time to move to higher ground. For locally generated tsunamis, where
you might feel the ground shake, you may only have a few minutes to move
to higher ground.
- High, multi-story, reinforced concrete hotels are located in many low-lying
coastal areas. The upper floors of these hotels can provide a safe place
to find refuge should there be a tsunami warning and you cannot move quickly
inland to higher ground. Local Civil Defense procedures may, however, not
allow this type of evacuation in your area. Homes and small buildings located
in low lying coastal areas are not designed to withstand tsunami impacts.
Do not stay in these structures should there be a tsunami warning.
- Offshore reefs and shallow areas may help break the force of tsunami
waves, but large and dangerous waves can still be threat to coastal residents
in these areas. Staying away fro all low-lying coastal areas is the safest
advice when there is a tsunami warning.
If You Are on a Boat or Ship
- Since tsunami wave activity is imperceptible in the open ocean, do
not return to port if you are at sea and a tsunami warning has been issued
for your area. Tsunamis can cause rapid changes in water level and unpredictable
dangerous currents in harbors and ports.
- If there is time to move your boat or ship from port to deep water
(after you know a tsunami warning has been issued), you should weigh the
- Most large harbors and ports are under the control of a harbor authority
and/or a vessel traffic system. These authorities direct operations during
periods of increased readiness (should a tsunami be expected), including
the forced movement of vessels if deemed necessary. Keep in contact with
the authorities should a forced movement of vessels be directed.
- Smaller ports may not be under the control of a harbor authority. If
you are aware there is a tsunami warning and you have time to move your
vessel to deep water, then you may want to do so in an orderly manner,
in consideration of other vessels. Owners of small boats may find it safest
to leave their boat at the pier and physically move to higher ground, particularly
in the event of a locally generated tsunami. Concurrent severe weather
conditions (rough seas outside of safe harbor) could present a greater
hazardous situation to small boats, so physically moving yourself to higher
ground may be the only option.
- Damaging wave activity and unpredictable currents can effect harbors
for a period of time following the initial tsunami impact on the coast.
Contact the harbor authority before returning to port making sure to verify
that conditions in the harbor are safe for navigation and berthing.
As dangerous as tsunamis are, they do not happen very often. You should
not let this natural hazard diminish your enjoyment of the beach and ocean.
But, if you think a tsunami may be coming, the ground shakes under your
feet or you hear there is a warning, tell your relatives and friends, and
move quickly to higher ground.
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