Cause of most tsunamis — underwater earthquake, in which there is a dramatic shift seabed, their sharp rise or fall. Tsunami can trigger an earthquake any power, but the greatest force reach tsunami generated after a magnitude 7 earthquake, balls and more. Tsunami in most cases occur in the peripheral regions of the Pacific.
Tsunami prone to attacks almost the entire coast of the Pacific Ocean. The most active seismic zone in the world is located at the junction of the Pacific and continental plates, the area is called "Ring of Fire", in this area there are very strong underwater earthquake. The most powerful known earthquake to date was a great Chilean earthquake that occurred 22 years maya1960, its magnitude was variously estimated from 9.2 to 9.5 balls. The result was a tsunami wave height which was 10 meters, its reverberations were felt even off the coast of Japan.
Kamchatka earthquake in 1952, ranked fourth in the ranking of the most powerful recorded earthquakes. Power earthquake was 9.0 on the Richter scale balls. From the tsunami, killing thousands of people, all of them were residents of the Kuril Islands and Kamchatka coast town of Severo-Kurilsk was destroyed completely.
Warning service before taking a decision on the alert and evacuation from coastal areas on the basis of seismic data — the epicenter distance and force pushes. This method allows you to determine the capacity of only about a tsunami, so it is not particularly effective for this reason many ads found to be false alarms. Population just ceased to respond, in a particularly powerful tsunami were casualties. Often receive the contrary, measures to evacuate the population and prevent the tsunami is much more expensive than the potential damage from a relatively small tsunami.
Over the last decade in operational forecasts tsunami there has been some progress. Back in the seventies, Soviet academician SL Soloviev proposed the idea of hydro-physical prediction, the application of this method is determined by the power of the tsunami sensors in sea level, set in the ocean at a considerable distance from the coastline.
After the collapse of the Soviet Union, according to the method of hydro-physical prediction had been dropped. To address this problem back in the last years. During this time the United States was able to create in the Pacific global system of control over the sensors generate tsunamis (DART). In order to improve the quality of forecasts for the coast of the Russian Far East, Roshydromet was bought one of these sensors has been installed near the island of Iturup in 2010. The work of the Russian service of the tsunami warning has become much more efficient. Which occurred March 11, 2011 off the coast of Japan's natural disaster is clearly demonstrated. The population of the Kuril Islands was timely warnings about the impending tsunami.
Today tsunami can be predicted with a high probability, but to predict the earthquake — tsunami cause more or less accurately, the researchers can not yet, of course, progress in the study of the origin of the earthquake processes currently available, but certain methods of its predictions are still exists . The present level of science to determine the probability of a possible earthquake, when scientists can solve the problem of earthquake prediction, mankind will finally be able to be fully prepared for those natural disasters, to whom it is currently virtually defenseless.