Tsunami - Major causes of rising waves

Tsunami – Major causes of rising waves

Question-Examine the factors causing Tsunami. Cite the differences in the reasons for the tsunami's of Fukushima in 2011 and the Indian Ocean in 2006.

Series of enormous waves which is the result of various land and underwater disturbances is termed as tsunami. It is usually associated with earthquakes, volcanic eruptions, submarine landslides, etc.

It is a displacement of a large volume of water due to earthquakes, volcanoes and landslides etc.

Earthquakes: When the crust below the sea suddenly deforms and transfers huge amount of energy into water, taking form of the surge. As the wave traverses entering shallow water in the coastal area, it begins to increase in amplitude.

Volcanoes: There are two ways in which a volcano can cause seismic waves. One is due to a land based volcano that breaks down and collapses, throwing large amounts of ash and debris into the water. This sudden displacement of the water transfers to kinetic energy resulting in huge waves. More the debris, bigger the waves. The other is submarine volcanoes which are underwater.

Landslides: Landslides are similar to volcanoes that avalanche into the sea. They occur in the water and often are triggered by earthquakes. They end up displacing huge masses of land.

Other Factors: Meteorite activity, man made nuclear blasts and glacial convulsions are some of the reasons for tsunamis.

Fukushima tsunami:

Fukushima Tsunami was caused due to an earthquake that occurred inside the Pacific ocean. The disturbance thus created flowed across the seas causing untold damage especially due to the water that entered into the nuclear reactor in Fukushima which polluted the environment with the radiation.

The earthquake was a reason of the slow building up pressure on the clashing tectonic plate, which led to deformation triggering the earthquake. The fault line is seen where the Pacific plate subducts under the American plate above which lies the Japanese Archipelago.

Indian ocean:

The Tsunami occurred in the Indian ocean in 2006 also was due to an earthquake that measured 7.7 on the richter scale. It took place along the subduction zone off west and central Java affecting the java island.

The reason was the violent movement of the Australian plate towards Sumatra which led to displacement of large amount of water along shock waves that led to the dreadful earthquake leading to huge losses.

Facts:

- A study has revealed that about 80% of tsunamis occur within the Pacific Ocean’s “Ring of Fire.”

- Greek historian Thucydides was the first to associate tsunamis with underwater earthquakes.

- Palm trees are well adapted to life on the shore and most often survive the impact of the tsunamis.