The word Tsunami comes from the Japanese tsu (harbor) and nami (wave), and it refers to tidal waves formed by underwater earthquakes, landslides, volcanic eruptions, explosions, and even the impact of cosmic bodies, such as meteorites.
Can you imagine that they can be faster than 400 miles per hours in the deep ocean? Although Tsunamis are called tidal waves, this is really not correct, as tides have nothing to do with them though the damage may be worse if a Tsunami hits at high tide. They are formed in deep water and may only be inches or a few feet high. But when it reaches a shoreline it becomes a wall of water that can be a mile high. The Japanese name was adopted because almost 80 percent of all Tsunami occur in the Pacific Ocean and Japan has suffered many, some coming from as away as South America.
Since 1990, there have been 82 Tsunamis, out of which 10 have claimed more than 4,000 lives. Tsunamis can savagely attack coastlines, causing devastating properly damage and loss of life.
According to researchers, there is a significant rise both in numbers of waves and in death tolls over the century. Up until now the average per decade has been 57. the increase in Tsunamis reported is due to improved global communications, the high death are partly due to the increase of people living in coastal areas.
One of the worst Tsunami disasters affected to Sri Lanka in 26th of December 2004.