TSUNAMI

Compiled by Chilman Sahni

The word tsunami comes from the Japanese tsu (meaning port) and nami (meaning wave). A tsunami is not a tidal wave, but a powerful surge of moving water caused by an earthquake or volcanic eruption beneath the sea bed. There may be advance warning signs, such as bubbling water, a roaring noise and a sudden rise in water temperature.

Tsunamis are rarely as high as tidal waves. However, powerful ones can cross huge distances, raising the sea level and destroying entire islands and coastal areas in their path. Lisbon, the capital of Portugal, was almost completely destroyed in 1755 by the combined effects of an earthquake, tsunami and fire. The worst recorded tsunami occurred in 2004 in South-east Asia.

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