Did You Know What That Tsunami?

addictNews, Jakarta - Japan hit by earthquake and massive tsunami that mewaskan many people last Friday. Actually, what is a tsunami?
Tsunami comes from the Japanese language, namely tsu means harbor and nami meaning wave. Literally, the tsunami means big waves in the harbor, Namu wider sense is the transfer of water bodies due to changes in sea surface vertically with a sudden.
Tsunamis often the case in Japan, there are at least 195 tsunamis have occurred. Therefore, sea waves caused by the earthquake this past used the term in the phrase / word Japanese.
Changes in sea level this could be caused by an earthquake centered under the sea, volcanic eruptions under the sea, underwater landslides, or hit by a meteor in the sea. Earthquakes can cause tsunami is the earthquake which centered in the middle of the sea and shallow (0-30 km) with a minimum strength of 6.5 on the Richter Scale (SR),
Besides earthquakes, cosmic objects or falling meteor could trigger a tsunami. If the object size is large enough, megatsunami which can occur hundreds of meters high and has the power to drown a few islands. Tsunami waves can propagate in all directions.
Power exist in the tsunami wave height depends on the functions and kelajuannya. In the deep ocean, tsunami waves can propagate with the speed of 500-1000 km per hour (equivalent to the speed of the aircraft). The height of these waves in the sea in only about one meter.
Similarly, the rate of the wave will not be felt that there are ships at sea. But when it approached the coast, its speed will decrease about 30 km per hour and dangerous, its height will be increased to tens of meters. Blow of the tsunami can extend up to tens of kilometers from the beach.
Material carried by this ferocious waves can cause damage and casualties. In addition, this wave will destroy anything in its path, starting from the buildings, plants and human casualties and causing inundation, water pollution salt in agricultural land, soil, and clean water.
The Greek historian Thucydides was the first to relate tsunamis to submarine earthquakes. But until the 20th century, knowledge about the cause of the tsunami is still very minimal.
Research continues to be done to understand the cause. Text geology, geography, and oceanography past called tsunamis as "seismic sea wave '.
Some of the meteorological conditions, including tropical storms that could trigger a tsunami wave height meteor storm a few feet above normal sea wave. When the storm made landfall looks like a tsunami, though not. This wave will inundate land, and have occurred in Myanmar in May 2008.
The area around the Pacific Ocean has the Pacific Tsunami Warning Centre (PTWC) which gives a warning if no tsunami threat in the region. The area around the Indian Ocean is being built Indian Ocean Tsunami Warning System (IOTWS), which will be based in Indonesia.