Definition: it is a wave or group of waves of great energy and size that take place when some extraordinary phenomenon displaces a great mass of water vertically.

The waves of a tsunami are gigantic and they move quickly, it measures a meter high when sea is inside.

As a tsunami travels toward the less deep waters of the coast, it slows down and it increases its size.

to have alarm systems and evacuation plans in case a dangerous tsunami is formed.

Another of the systems for the tsunamis prevention is the project CREST (Consolidated Reporting of Earthquakes and Tsunamis) that is used in the North American coast west and in Hawai.

The worst disaster caused by a tsunami was in December of 2004, when a marine earthquake of magnitude 9,0 in the scale of Richter, in the Indian ocean, i generated a tsunami that reached the costs of 14 countries.

They registered more than 250.000 deaths, of those almost 2/3 died in Indonesia; there were also numerous victims in India, Sri Lanka and Thailand.