Tsunami: Causes and prevention

Tsunami:

Tsunami waves are made in ocean by an earthquake, volcanic eruption or in rare cases, meteorite impact.

Causes:

Tsunamis are capable of causing large destruction while hitting the coastline. When tsunami waves travel into shallow waters near the shore, they slow down and grow in height and when they finally reach the coast, the height of tsunami waves can be as high as thirty meters and can move inlands, several hundred meters.

Tsunami comprises of a series of waves with crests arriving every ten to sixty minutes. Usually, the first wave may not be the largest but the subsequent waves are capable of being large, causing greater destruction. The subsequent waves may also arrive even hours after the arrival of the first wave. Unlike tidal waves tsunami waves do not curl and break.

More often than not, tsunami waves cause the sea water enter the shore and recede, exposing the ocean floor. Tsunamis can travel up rivers and streams from the ocean. The force of the tsunami waves is unimaginable. As a result of tsunami waves, large rocks and other materials that weigh several tonnes along with boats and debris can be washed away inlands, hundreds of meters. The force is such that homes and buildings will be destroyed and can kill or injure people.

Steps to be taken:

Although there are no measures to predict a tsunami well before it strikes, however, the damage can be minimized by taking some precautionary steps.

1. The first is to heed to the official warnings because most probably, tsunami is followed by under water earthquake and when officials announce a warning, it is better to heed to their warnings.

2. Often, tsunami waves are followed by subsequent bigger waves and so, it is not wise to decide that the worst is over when the first wave strikes. There may be a bigger danger following.

3. The best thing is to head for high ground or a hill top and stay there.

4. The most foolish thing is to try to take the belongings or precious things, as nothing is more precious and costlier than human life.

5. If staying in a building, people must go to the upper floor or the roof of the building.

6. Climbing a strong tree is also a good idea.

7. If washed away by waters; climb onto to something that floats.

8. The worst thing is, even after the tsunami waves have receded, after- tremors of earth quake may occur and people must be ready to face it.

Images: Kalutara beach, Sri Lanka (Before and after Tsunami)

Banda Aceh Northern Shore, Indonesia (Before and after Tsunami)

Courtesy: Image storage space provided by: Apple’s .Mac

Author: K, Chandra (Chennai)