�As the tsunami enters the shoaling water near the coast, its velocity decreases and its height increases. It is in these shallow waters that tsunamis become a threat to life and property, for they can crest to heights of more than 30-50 meters and strike with devastating force.
 

Tsunamis are among the most terrifying natural hazards known to man. They have been responsible for tremendous loss of life and property throughout history.�

Citation source: http://www.drgeorgepc.com/TsunamiFAQ.html

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