1. Consequences of 2 tsunami exercises in 2005, in French Polynesia :
evolution of the tsunami warning
Dominique Reymond
LDG/DASE/CEA :
Laboratoire de Geophysique de Tahiti
Departement d’Analyse Surveillance Environnement
Commissariat a l’Energie Atomique
Colonel Denis Musson
DPC
Direction de la Protection Civile,
Haut-commissariat de la République
en Polynésie Française

2. Summary
Tsunami in French Polynesia : generalities
Tsunami warning plan : share of competencies
The different Levels of warning
The basis of warning system
The 2 excercices of 2005

3. The 20th century’s most dangerous tsunami in Polynesia (with amplitudes exceeding 2 m in French Polynesia)
Kamchatka,
Nov. 1952, M 9.0
Aléoutian,
Mars 1957, M 8.7
Aleutian,
1 avr 1946, M 8.5
Alaska,
Mars 1964, M 9.2
Peru,
Fev. 1996, M 7.5
Chili,
Jul 1995, M 8.0
French
Polynesia
South Chili,
Mai 1960, M 9.5

4. The Marquesas islands, a vulnerable archipelago : measured heights in Hiva Oa and Nuku Hiva, April 1st 1946
Tsunami field survey of
E. Okal & al.
CEA/DASE/LDG

5. Hiva Oa (Marquesas) : the Chilean tsunami on July 30th 1995 (mag 8.0)
CEA/DASE/LDG_Tahiti
Hiva Oa (Marquesas) : the Chilean tsunami on July 30th 1995 (mag 8.0)
Run-up # 3-4 m
1 Avril 1946 – Hilo - Hawaii
9 mars 1957 – Oahu - Hawaii

6. Propagation time from main subduction zones to French Polynesia
Japan, Kuril,
Kamchtaka
hours
Aleutian
11 hours
Tonga
3 -4 hours
Chile - Peru
hours
CPPT : Centre Polynésien de prévention des Tsunamis

7. The tsunami warning plan The role of the High-commissioner :
He is the represantative of the French Government
He is the authority in charge of the activation of the plan and the relief and emergency coordination.
The activation of the whole, or a part, of the Plan is decided by the High-commissioner on the basis of the observations and recommendations submitted by the LDG.
This Plan must be continued by local communities.

8. The tsunami warning plan: the role of the Mayor
In accordance with the District Code, the mayor is in charge of anticipating, and providing all necessary assistance:
He is in charge of the information of all inhabitants in his district.
Each mayor ensures that population has taken all useful precautions for its security

9. Tremors : Overview of the automatic seismic warning system
3 components
seismic data of
a single station
Seismologist 24h/24h on duty
Warning from a given threshold (mag 7.0) N Z E
Data acquisition
Realtime analysis of seismic data
by a PC computer
Warning to Civil Defense
Detection
Location
Magnitude, Mo
TREMORS: Tsunami Risk Estimation through a Real-time System
CEA/DASE/LDG

10. The tsunami warning plan: Alert levels

11. Territorial administrator
Flow-chart of present warning to populations
LDG
LEVEL 2
HC - DPC
Territorial administrator
The warning could start at any level in function of available delays
LEVEL 3
Mayor
TV, radio
LEVEL 4
Populations

12. Drills
2 exercises were organized in 2005: to test the tsunami plan about the international airport of Tahiti to test effective warning to the population in Marquesas islands. 1 valley on 3 islands was evacuated.

13. the case of the international airport of Tahiti
The numerical simulation shows the inundation of technical installations : - carburant tanks zone, - part of the tarmac, - electrical supply installation, - flying lights and transmissions.

14. The case of the international airport of Tahiti
If the airport could be out of order, some reflex rules were elaborated about, for example : - rerouting of the flying planes, sheltering landed planes - protection of technical equipments, engines and installations, - evacuation and security of the public zone, - measures for restarting quickly the airport. On the other hand, a restructuring of the airport is programmed for economical reasons. The result of numerical simulation will be integrated in the project.

15. Drill in Marquesas
The warning chain was tested : LDG, HC-DPC, Territorial administrator, mayor, population.
The usual supports, telephone, fax, local radio station and .. bells, were used.
New other were tested: recorded message by phone and SMS.
There is no siren in these island whose communities are isolated.

16. Drill in Marquesas test of new transmission supports
* The recorded message concerned : local authorities, hotel with tourists, administrations of school, hospital, etc … * The message in French, Marquesian and English, was recorded in 30 minutes; * 90 min was necessary for the transmission. * 38 /40 addresses received this message. * The weakness of this option: there is nobody in 24h/24h on duty at the French Polynesian telephone service provider

17. Drill in Marquesas test of new transmission supports (cont.)
* The diffusion of the warning by SMS require 65 minutes to input the message in three languages, and to find the phone references of foreigner tourists. * In one hour, 44% of the 1145 local cellular phones were contacted, but 0% of the 52 foreigners. *Furthermore, this system perturbed normal vocal channels. * Evidently, this interesting possibility is not adapted for a rapid warning.

18. Drill in Marquesas
Evacuations : this exercise was prepared with the communal authorities and the communities : 200 to 1000 inhabitants. But 1h to 1h45 was necessary to evacuate. The real difficulty is to join these isolated communities. Recently, the French Polynesia was hit by a large swell. Some little atolls of Tuamotu archipelago needed 36 hours for joining them.

19. The new tsunami warning system the scattering of the communities on 5 million kilometer square
Drill

20. The new tsunami warning system
LDG
DPC
community
TAHITI
150 remote controlled sirens by inmarsat C, will be installed in all of the communities on the territory in 2005 to This network is secured by 2 permanent satellites. The large hotels on lagoon will be equipped too.

21. Remote controlled siren
15000 us dollars, battery, solar panels and transceiver included.
This equipment transmit informations about the status of siren and its battery.
this siren network will be tested once/month.

22. The next excercise
In February 2006, the topic will be to test this siren network and the evacuation of population of the 6 valleys of Hiva Oa (Marquesas).

23. End