Home

A tsunami is a series of seismic sea waves generated by movement on the ocean floor (either by earthquakes or large underwater landslides).

The Pacific Tsunami Warning Centre is based in Honolulu, Hawaii.   When a strong earthquake occurs in the Pacific area, New Zealand and other members of the Pacific Tsunami Warning System are notified by the centre in Honolulu.  
A "tsunami watch" is commenced, and continues until either a tsunami is confirmed as having developed, or until it is certain that no danger exists.

The first positive indication that a tsunami exists usually comes from the tidal report station nearest the disturbance.   When confirmation is received that a tsunami exists, the Pacific Tsunami Warning Centre issues a tsunami warning.   When a tsunami warning is received, the Ministry for Emergency Management issues a national warning through the Police to Civil Defence organisations, and through nation-wide radio and television broadcasts.

When a warning is issued - follow the instructions that are given.

A "near source" tsunami is one that is generated close to a coastline by a strong earthquake. (New Zealand has experienced a few of these in the past).   The water level may fall very quickly past the normal low tide mark.   Then it may return just as quickly.   If this happens there won’t be enough time to issue a warning.

Things to know before a Tsunami strikes:

Know the Civil Defence warning signal for your area
Know how to reach the nearest safe ground 
Form a survival plan for;
... Your family
... Your pets
Maintain your disaster survival kit
Know how to turn off electricity and gas supplies at the mains
 

When a Tsunami threatens

If you hear the Civil Defence warning signal
... turn on your radio and follow all instructions.

Do not evacuate your home unless told to. 
If told to evacuate – DO SO IMMEDIATELY

Take your disaster kit with you 
... Don't forget important documents

If you are on the beach or near a river when a strong earthuake occurs - leave the area immediately. Don't stop to pick up belongings.

Go at least 1 km inland or 35 metres abovce sea level

Do not go to a river or beach to watch the waves come in - if you see the Tsunami it will be too late to escape

KNOW WHAT TO DO BEFORE YOU HAVE TO DO IT!

Tsunamis can occur anywhere in the Pacific where there is an undersea earthquake or landslide.   Seismographs and tide stations throughout the Pacific pinpoint the site of the earthquake or landslide.   This information is then passed to the Pacific Tsunami Warning Centre in Honolulu, and then details of the tsunami, once confirmed, are issued to all stations in the Pacific.