A tsunami is a series of large waves of extremely long length and generated by a violent, impulsive undersea disturbance or activity near the coast or in the ocean. When a sudden displacement of a large volume of water occurs, or if the sea floor is suddenly raised or dropped by an earthquake, big tsunami waves can be formed. The tsunami in the recorded time period with the highest death toll happened in the Indian Ocean in December 2004 (more than 230.000 people died), but the highest economical damages (more than 200 billion US$) were caused by the tsunami in 2011 that hit the nuclear power plant in Fukushima, Japan. Most of the recorded tsunamis happened in Indonesia followed by Chile and Japan.
According to recent studies an increased occurrence of such events due to climate change and global warming is highly likely.
