Environmental Visualization Laboratory - Pacific Ocean Floor Affects Tsunami Propagation. As tsunami waves travel across ocean basins they are only centimeters high, but extend down to the ocean floor (unlike traditional waves which are only surface features).
As the tsunami waves approaches the coast, the shallowing ocean floor pushes the water mass upwards. The quicker the ocean floor transitions from deep to shallow, the greater potential for a higher wave height. The epicenter of the earthquake that triggered the recent Japanese tsunami was very close to shore, though, which reduced the amount of the water column that is displaced and the overall tsunami height.
Natural Hazards. Tsunami Indonesia. ISDR: Platform for the Promotion of Early Warning. Compared to other natural hazards (tropical storms, floods, droughts, etc.) destructive tsunamis occur relatively rare.
But the recent tsunami in the Indian Ocean dramatically showed what could happen if a tsunami waves triggered by a major earthquake reaches coastal areas without any early warning. The highly energetic tsunami waves struck the costal areas devastating everything on their path. The costal population lost everything, most of the poorly built houses could not stand the massive flood or they were destroyed by flooding material. Tsunami Laboratory, Novosibirsk, Russia.