Tsunamis are huge waves of ocean water caused by a disturbance of the ocean floor usually by an earthquake.
When movements such as earthquakes occur in oceans they create uplifted and tilted ocean floors which disturbs the inertia of water and generates huge waves of water travelling at speeds of more than 600km/hr.
The waveheight is generally low compared to the wavelengths but can increase on land while the wave length decreases.On land the speed reduces due to friction.
Tsunamis are one of the most devastating phenomenons generated by tectonic activities and seldom occurs.The 2004 Boxing Day Tsunami is perhaps one of tthe most devasting tsunami.
With its origin around the Indian Ocean the tsunami devasted nearby countries especially Indonesia and Thailand.
Over 200 00 people died and some reported missing.Over one million were made homeless and unemployment rose sharply. Reparation costs reached up to 15 billion.