The origin of Tsunamis

The events of the tsunami

This geological hazard should not be confused with swell or high wave phenomena caused by abnormal weather conditions, such as wind or rain. It is therefore possible for a tsunami to form when the weather is fine.

Most tsunamis are caused by underwater earthquakes. These earthquakes, when they are powerful, make it vibrate a large amount of water. The waves propagate in all directions. Other events may also move a large amount of water and create tsunamis by domino effect. For example, a large landslide into the sea or an underwater volcanic eruption.

The warning signs of a tsunami

• The earth can shake, but you don't feel it necessarily.
• The sea may suddenly recede, exposing the seabed.
• Some animals may have a strange behavior (excitation, flight to the heights).
• We can hear a rumbling or strange noises coming from the sea.

Source : Booklet teacher-cycle 4 – Project "Pare pa Pare" – French Red Cross – 2024

For more information :

Caribbean | Tsunami Programme Member States concerned by Tsunamis, prevention, local exercices and warning center. Unesco (English)

Tsunamis – CDEMA - Ressources for understanding tsunamis and be prepared for their come. (English)

Tsunamis – UWI Explanations on tsunamis. West Indies University (English)

Risk coastlines – Geohazards – French Government. Resource to understand what a tsunami is, its risks, the useful actions to protect oneself, and the available French subsidies. (French)