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TsunamiPhenomenon

Tsunami is a catastrophic ocean wave, mostly caused by a submarine earthquake less than 50 kilometers under the seafloor with a magnitude greater than 6.5 on Richter scale. Near the source of submarine earthquakes, the seafloor is “permanently” uplifted and down-dropped, pushing the water up and down. The potential energy from pushing water is transformed to kinetic energy seen as the tsunami wave

Even if a wave is 15 meters high (not likely in tsunamis) it makes a little difference in a hundred meters deep water but, as it comes into shallow water, the wave rises much higher and strikes the shore with very devastating force. In deep water wavelengths are enormous (100km to 200km) and wave heights are pretty small, less than 1 meter but as the waves approach the continental coasts, shallow water reduces the speed of the waves shortening the wavelengths and amplifying wave amplitudes up to 30 meters in just 10 to 15 minutes what is very fast transition. Tsunamis can be also caused by landslides or volcanic eruptions

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