Wednesday, January 03, 2007

Pacific Tsunami Warning Center - About Tsunamis

Pacific Tsunami Warning Center - About Tsunamis: "About Tsunamis
'Tsunami' is the Japanese term meaning wave in the harbor. As such it is most descriptive of the observed phenomenon frequently referred to as tidal wave or seismic sea wave, with both of these terms having misleading connotations with respect to the mechanism of generation. In South America, the term 'maremoto' is frequently used. However the use of the word 'tsunami' is most commonly accepted by scientists and by most of the lay public in Pacific basin countries. For the TWS, tsunamis can be categorized as local, regional, or Pacific-wide, with those terms being used to describe the extent of potential destruction relative to the tsunami source area. Local tsunamis will often be associated with tsunami generation by submarine or subaerial landslides or volcanic explosions. An example would be the awesome local tsunami of July 9, 1958, at Lituya Bay, Alaska, where wave run-up exceeded 485 meters but the destruction was confined to a very limited area. Regional tsunamis are by far the most common. Destruction may be limited in areal extent either because the energy released was not sufficient to generate a destructive Pacific-wide tsunami, or because the geomorphology of the source area limited the destructive potential of the tsunami. Examples of some recent tsunamis are shown in the table below:

Date Magnitude Max Ht Killed "

No comments: