The term tsunami is not part of the words accepted by the dictionary of the Royal Spanish Academy (RAE) . Anyway, it is a word widely used as a synonym for seaquake , although its meaning refers to a wave That sweeps the coast.
Therefore, in both cases there is a violent agitation of the waters of sea, from one shake From the bottom. The tsunami can spread to the beaches and cause severe flooding and a considerable level of destruction that is difficult to overcome for a city with limited resources.
The aforementioned shaking of the bottom of the ocean it is usually caused by a earthquake which generates the vertical displacement of water. In these cases, the most accurate is to talk about tectonic tidal wave .
However, the concept of tsunami is also used to refer to the giant waves that are caused by hurricanes or temporary , although it is only about surface waves produced by a wind very strong.
The last major tsunami took place on December 26, 2004 in Asia , with epicenter on the west coast of Sumatra (Indonesia ). The phenomenon was caused by an earthquake in the Indian Ocean which promoted the tsunami and caused the flood of many stocks Coastal
Specialists estimate that, because of this tsunami, some died 230,000 people . The magnitude of the earthquake was such that it stood at 9.3 of the scale of Richter , which makes it the second earthquake larger since the seismograph was invented.
A phenomenon that has become very popular in recent years, since the catastrophe of 2004, is the megatsunami; it is a tsunami that considerably exceeds the height of one normal, or, caused by an earthquake. There is talk of an average of half kilometer elevation of a wave that is able to move through the ocean to a speed exceeding 400 km / h and, contrary to his younger brothers, leave the coast behind and break up a long time later, having caused an irreparable level of destruction, burying entire cities in its path.
Although our planet It has witnessed more than one megatsunami in its history, the cases investigated date from such distant times that it is not possible to access testimonies or statements that help to reconstruct the facts. It is also impossible to specify the date and location of the next megatsunami that will hit the Earth, although it is known with certainty that it will take place and that its consequences will be devastating.
Taking up the cases that the investigators know, it is believed that the trigger of the tsunamis of the past was the collapse of volcanic islands; since these arise from an eruption of wash which solidifies when it comes into contact with water, it looks like a cone with the tip directed towards the bottom of the ocean. Over several millennia, their bases are inevitably eroded until the islands collapse and submerge violently, which causes a giant body of water to rise and be driven at full speed.
The current concern is centered on the island of La Palma, belonging to the Canary Islands archipelago. Since it has a peculiar instability because of housing large volumes of Water rain inside, and that brings together requirements necessary, such as his age, there is no doubt of his impending collapse; It is estimated that the target This megatsunami will be the East Coast of the United States, which will suffer damage only imagined in films about natural disasters that force human beings to rebuild their civilization.