Tsunami Facts

The word Tsunami comes from Japanese language – Tsu means harbour and nami means wave.

When the water on an ocean bed or a sea bed is displaced vertically, causing disturbance in the equilibrium, Tsunami is formed. The waves of Tsunami can range from 10 metres high to 150 metres high in extreme cases. The fast displacement of huge amount of water takes place because of one or more of following reasons.

1. Volcanic eruptions,
2. Massive earthquakes at the ocean bed,
3. Underwater explosions,
4. Nuclear testing in seas and
5. Cosmo-body impacts.

How Tsunami begins

Abrupt deformation of plate boundaries causes the displacement of water vertically in a sea. In pursuit of getting equilibrium, large waves are formed and are known as Tsunamis.

Indications of an upcoming Tsunami

1. An earthquake near a water body like sea indicates that a Tsunami is most likely to occur some time soon.
2. If the usually submerged part of the sea shore is exposed, it can be understood that a Tsunami is likely to strike in few minutes.
3. If a herd of elephant is seen moving in the opposite direction of the sea, it indicates that they have heard the sound of an approaching Tsunami.
4. The time and impact of an upcoming Tsunami can be computed, if the knowledge of, the cause behind the Tsunami and the shape of the ocean bed, is gained.
5. A loud roar of water can indicate the fast approaching killer waves.

Tsunami Prediction and Warning System

These kind of systems comprise of two parts; a giant network of sensors to detect Tsunamis and an efficient alarm system for coastal evacuation.

The underlying principle behind such warning systems is that Tsunamis travel at a speed of 0.14 to 0.28 km/sec and seismic waves of 4 km/sec. Thus, usually there is sufficient time to evacuate when a Tsunami is predicted.

Safety Measures against Tsunami

Japan is one of the countries, which has been hit by Tsunami time and again. The country has built Tsunami walls of 4.5 metres high along the densely populated coastal areas. Many nations have built floodgates and channels to redirect Tsunami water. Also we see a tree cover made along the shore. All these measures can reduce the damage caused by Tsunami but they can’t totally eliminate the chances of destruction.

Some figures related to Tsunami

1. Maximum life lost due to a Tsunami was is 2004 when the killer waves killed over 283,000 people and cause a mass destruction of properties from Thailand to Africa. The worst Tsunami occurred in Indian ocean and left more than 11 countries in misery.
2. In 1755 the second largest Tsunami rocked Portugal, Morocco and United Kingdom causing death toll to go upto 100,000.
3. The third largest carnage was caused in the year of 1908 in Italy. The total number of life lost touched 70,000 mark.

More Tsunami Facts

At the deepest point of the oceans Tsunamis can travel at 600 mph. When they reach the shore, the speed gets reduced to 30 mph to 40 mph.The energy of the waves get transformed to height and massive force. It can travel all across the ocean without much loss of energy.

Tsunami waves can be as long as 100 kms and can be one hour apart from each other. There is no fixed time for Tsunami to occur, which means it can strike at any point of time and it runs much faster than human being.

Mega Tsunami

When the waves of Tsunami reach the height of 40 metres to 100 metres, they are termed as megatsunami. At some places they are also referred as “iminami” and at some others, they are called as “wave of purification”.