A report on the response to the tsunami that hit Samoa shows that preparedness and evacuation planning saved lives even though they had barely eight minutes after the warning from the Pacific Tsunami Warning Center. Countries like India, Bangladesh and Sri Lanka have enough distance from the unstable Sunda Trench and therefore are likely to have more time to organize evacuations. For Indonesia and Thailand, unfortunately, the time will be less.
The Pacific islands were so close to the epicentre of the earthquake that a wall of water hit Samoa within eight minutes after the Tsunami Warning Center in Hawaii sent its first bulletin Tuesday.
Several Samoans said they heard no sirens or warnings, but fled as soon as they were woken up by the earthquake.
Nevertheless, the fact that scores left for safety underlined that lessons from the 2004 Indian Ocean tsunamis have not been forgotten.
Excerpt from UNISDR communique
2 October 2009
The UNISDR is deeply sorry for all the families and communities who have been affected by the floods in the Philippines and Vietnam, the tsunami in Samoa and Tonga, and the earthquakes in Indonesia. We are now waiting for more assessments to be able to draw the lessons from these new tragedies. But here is what we can say:
• The Pacific Tsunami Warning and Mitigation System coordinated by UNESCO’s Intergovernmental Oceanographic Commission (IOC) issued a clear warning throughout the region 16 minutes after the quake on 29 September 2009. In regions very close to the site of the earthquake, the short time available to warn and evacuate coastal populations posed a major challenge to local authorities and coastal residents in some areas did not get the information in time. This has been confirmed by UNESCO. Contact: Sue Williams, Bureau of Public Information, +33 (0)1 45 68 17 06 firstname.lastname@example.org
• People who have been able to receive the warning messages evacuated to upper grounds and their lives were saved. The response appears to have been good and many people seem to have learned the lessons from the 2004 tsunami in the Indian Ocean.
• Early warning systems have many components. They need to have a strong scientific and technical basis but they also need to be: people-centred, tailored to the local risks that people are exposed to, and designed to provide understandable information to all of those at risk. If all four components are implemented, people will be able to act promptly and in a manner that reduces injuries, loss of life and damage to property. For more information see: http://www.unisdr.org/ppew/tsunami/pdf/lesson-for-a-safer-future.pdf
Also review the four elements of effective EW systems at http://www.unisdr.org/ppew/whats-ew/basics-ew.htm
• Technology is one part of the early warning system components but the social component is even more important. A warning network has to be in place to deliver the message to the public 24/7 and populations need to be prepared and to understand what actions need to be taken done when the alert has been given. Evacuation routes have to be safe. Populations can be empowered and educated with tsunami plans, preparedness and regular drills.
• Samoa does have an approved Tsunami Plan (since 2006) and has carried out several tsunami drills or exercises which have helped to prepare the government and the public but despite good preparedness, there have still been many losses.