Tsunami warning

The Pacific Ocean alert system has existed since 1965. Following the tsunami centred on Sumatra (26 December, 2004) and the Kobe conference (18–22 January, 2005), UNESCO's intergovernmental oceanographic commission was asked to implement additional tsunami alert systems in the Indian Ocean, in the Caribbean, and in the Northeast Atlantic and Mediterranean.


La grande vague de Kanagawa



The goal is to create and operate regional centres in these four ocean regions. Their mission will be to:

  • Detect seismic events that can lead to a tsunami
  • Determine the physical parameters of the tsunami
  • Alert national and local authorities who must protect their populations


map reseaux alertes tsunamis



Note that the SHOM, for the establishment of tsunami early warning systems, plays a unique role in the deployment and maintenance of tide gauges on all the world's oceans.


How a tsunami warning system works


The tsunami warning system is organized in two phases:

  • The incoming alert detects earthquakes and tsunamis with seismological and tidal instruments  and transmits this information to the regional warning centre. This is where scientists play a role. The regional warning centre will, if necessary, alert the authorities of each country.
  • This is the second phase: the outgoing alert handled by the civil security service in coordination with local authorities to advise people of the danger and evacuate the coast.


To find out more:

Tsunami Les grandes vagues

Couverture Glossaire sur les tsunamis

Les tsunamis en mouvement



UNESCO IOC (2008). Tsunami preparedness Information guide for disaster planners. Manuals and Guides No. 49, 29 p.



Last updated: 12/12/2012