What is a tsunami?

A tsunami (soo-NAH-mee) is a series of traveling ocean waves of extremely long length. These generally appear as a large, steep wave face and produce rapid flooding of low-lying coastal areas. These are generated by disturbances associated primarily with earthquakes occurring below or near the ocean floor. This can also be generated by landslides, both above and beneath the surface of the ocean. 

It may take hours for tsunami waves to reach the Coast of Maui County following an earthquake far out in the Pacific Ocean. The Pacific Tsunami Warning Center located on Oahu alerts local officials who may order evacuation. Some isolated areas may not receive official announcements. If you notice a sudden drop or rise in sea level, it may be a warning of impending danger. Move to high ground or inland immediately. 

The waves can kill and injure people and cause great property damage where they come ashore. The first wave is often not the largest and may be spaced many miles and minutes apart. They may also continue to arrive for several hours. 

The most destructive tsunami can be classified as local or regional, meaning their destructive effects are confined to coasts within 60 - 600 miles of the source -- usually an earthquake. It follows that the majority of tsunami related casualties and property damage also come from a local tsunami. Between 1975 and 1998 there have been at least eighteen in the Pacific and its adjacent seas resulting in significant casualties and/or property damage.

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1. What should I do when I hear the Emergency Management Agency sirens?
2. What is the difference between a WATCH and a WARNING?
3. Should I evacuate or stay where I am?
4. What should I do to protect my pets/animals?
5. What should my family and I take to the shelter?
6. Where is the nearest evacuation shelter/emergency shelter?
7. I am a visitor at a hotel. What should I do when a disaster is imminent?
8. What should I do during a hurricane?
9. Will tourists be evacuated after a disaster strikes?
10. What to do BEFORE a disaster strikes:
11. What to do WHEN disaster strikes:
12. What is a tsunami?
13. Where and when do tsunamis occur?
14. How do I know when to evacuate?
15. Where do I evacuate?
16. How do I get to inland or to high ground?
17. What should I do if an earthquake occurs while at the coast?
18. What can I do to protect myself from a tsunami?