Colonel Denis MussonDPC Direction de la Protection

Civile,Haut-commissariat de la République en Polynésie Française

Dominique ReymondLDG/DASE/CEA :Laboratoire de Geophysique de TahitiDepartement d’Analyse Surveillance

EnvironnementCommissariat a l’Energie Atomique

Consequences of 2 tsunami exercises

in 2005, in French Polynesia : evolution of the tsunami

warning

Tsunami in French Polynesia : generalities

Tsunami warning plan : share of competencies

The different Levels of warningThe basis of warning system

The 2 excercices of 2005

Summary

FrenchPolynesia

South Chili,Mai 1960, M 9.5

Chili,Jul 1995, M 8.0

Peru,Fev. 1996, M 7.5

Alaska,Mars 1964, M 9.2

Aleutian,1 avr 1946, M 8.5

Aléoutian,Mars 1957, M 8.7

Kamchatka,Nov. 1952, M 9.0

The 20th century’s most dangerous tsunami in Polynesia (with amplitudes exceeding 2 m in

French Polynesia)

The Marquesas islands, a vulnerable archipelago : measured heights in Hiva Oa and Nuku Hiva, April 1st

1946

CEA/DASE/LDG

Tsunami field survey ofE. Okal & al.

CEA/DASE/LDG_Tahiti

9 mars 1957 – Oahu - Hawaii1 Avril 1946 – Hilo - Hawaii

Hiva Oa (Marquesas) :

the Chilean tsunami on July 30th 1995 (mag 8.0)

Run-up # 3-4 m

Tonga3 -4 hours Chile - Peru

10 - 11 hours

Aleutian11 hours

Propagation time from main subduction zonesto French Polynesia

Japan, Kuril,Kamchtaka12-13 hours

CPPT : Centre Polynésien de prévention des Tsunamis

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.

The tsunami warning planThe role of the High-commissioner :

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

The tsunami warning plan:the role of the Mayor

Data acquisition

3 components seismic data of a single station

Realtime analysis of seismic databy a PC computer

Location Detection Magnitude, Mo

Warning from a given threshold (mag 7.0)

Seismologist 24h/24h on duty

Warning to Civil Defense

CEA/DASE/LDG

Tremors : Overview of the automatic seismic warning system

TREMORS: Tsunami Risk Estimation through a Real-time System

NZ

E

Magnitude Mm > 8 7 < Mm < 9

Location coming from TONGA any except TONGA

9 hours level 2

6 hours level 3

3 hours level 4 level 4

return to normal level 1 level 1

* Transfer from a level to another is automatic, except on information given by LDG

GREEN level 1 normal situation (wakefulness)YELLOW level 2 central alert (HC + local government)ORANGE level 3 local alert (districts)

RED level 4 general alert (population evacuation)GREEN level 1 return to normal situation,launched on LDG communication

The tsunami warning plan:Alert levels

LEV

EL

3LE

VEL

2LE

VEL

4

HC - DPC

Flow-chart of present warning to populations

The warning could start at any level in function of available delays

LDG

Territorial administrator

TV, radio

Mayor

Populations

Drills

2 exercises were organized in 2005:

1 - to test the tsunami plan about the international airport of Tahiti

2 - to test effective warning to the population in Marquesas islands. 1 valley on 3 islands was evacuated.

the case of the international airport of TahitiThe numerical simulation shows the inundation of technical installations :

- carburant tanks zone,

- part of the tarmac,

- electrical supply installation,

- flying lights and transmissions.

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.

Drill in Marquesas

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.

The warning chain was tested : LDG, HC-DPC, Territorial administrator, mayor, population.

* 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

Drill in Marquesastest of new transmission supports

Drill in Marquesastest 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.

Drill in MarquesasEvacuations : 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.

Drill

The new tsunami warning systemthe scattering of the communities on 5 million kilometer

square

150 remote controlled sirens by inmarsat C, will be installed in all of the communities on the territory in 2005 to 2007.This network is secured by 2 permanent satellites.The large hotels on lagoon will be equipped too.

The new tsunami warning system

TAHITI

LDGcommuni

ty

DPC

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.

Remote controlled siren

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).

The next excercise

EndEnd