Oceans and disasters

Look again at the photo of the Earth: there are white swirls across the globe. They are huge masses of cloud.

Clouds like these bring rain to the continents. The monsoon rains India waits for every summer begin over the ocean. Without such rain, our farming and all life would suffer.

But the ocean also brings storms: violent weather with very heavy rain or very strong winds, such as cyclones, which can do great damage along coasts. The same ocean that feeds the fields can flatten a village.

A tsunami is another disaster that starts in the ocean. It is a huge, powerful wave, usually caused by a strong earthquake or a volcanic eruption at the bottom of the ocean. A tsunami can travel thousands of kilometres and flood coasts far away.

On 26 December 2004, India and 13 other countries around the Indian Ocean were hit by a powerful tsunami caused by an earthquake in Indonesia. More than two lakh people died. In India, the Andaman and Nicobar Islands and the coasts of Tamil Nadu and Kerala were badly hit.

Tsunamis are rare but very destructive. Luckily, they can often be detected before they reach a coast. Many countries work together in early warning systems; there is an Indian Ocean Tsunami Warning System, to which India and many other countries contribute. Because the wave has to travel so far, there is time to warn people, if someone is watching and the message reaches the coast in time.

Events that cause loss of life and property are handled under disaster management. India has its own National Disaster Management Authority to deal with all kinds of disasters.