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Tsunami Early WarningSome thoughts and Lessons learned

Jörn LauterjungGFZ Potsdam

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Tsunami-prone Areas

Sumatra, 2004Mentawai, 2010

Java, 2006

Japan, 2011

Chile, 2010

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The International UNESCO FrameworkIntergovernmental Coordination Groups (ICG)

ICG PTWS

ICG IOTWS

ICG NEAMTWS

ICG CARIBE

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General layout of warning systems (end-to-end approach)

Sensorsystems•Seismometer•cGPS•Tide Gauge•Buoy Systems•Others

Warning Centre•Processing•Simulation•Descision-Support•Warning Message

Up-Stream

Measurement, Analysis, Decision

Dissem

inatio

nLocal Communities

Down-Stream

t

Awareness, Preparedness, Reaction

Local Administration

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Warning ProcessRealization in Indonesia

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Warning Process

Patch concept: 2250 Patches of 45x15 kmTsunamigenic zone (0-80 km depth)Displacement model 1D layered (Wang et al.,2003)> 3500 Scenarios in Tsunami Database

Scenarios - Source Generator

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Warning Process

Far-field tsunamiLong tsunami travel distance compared to earthquake rupture length. In this case the rupture orientation (given by the fault orientation) is essential but details like the exact position of the rupture or slip distribution are not critical for tsunami forecast at a given coastal point.

Near-field tsunamiTsunami travel distance in a similar order (of magnitude) of the earthquake rupture length. Exact position and parameters of the rupture plane as well as the slip distribution are essential for tsunami forecast at a given coastal point.

The Problem of Near Field Tsunami Forecasting

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Warning ProcessHonshu Earthquake (11. 3. 2011)

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Warning ProcessHonshu Earthquake (11. 3. 2011)

matching

Numerical World

Multi Sensor Szenario Selection

EQ parameters → RuptGen → TsunAWI

EQ parameters Deformation vector Ocean surface

Physical World

Quake → co-seismic deformation → Tsunamiwave →

Inundationsensor systems

SeisComp3 CGPS Tide GaugesBuoys

EQ parameters Deformation vector Ocean surface

matching matching matching

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Warning ProcessDecision Support SystemSituation and Decision perspective

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Warning Process

Simulation

Situation picture

Evacuation

Risk maps

Planning

1) Situation picture using tsunami simulation within 5 minutes:Simulation selection from data base using many different sensors improved situation judgement, help to overcome uncertainties

2) Simulation used as tool for planning and disaster management

Simulation and Warningprocess

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Simple rule-based decision process (decision matrix)

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Simple decision process, based on precalculated hazard maps

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Warning Process• Tsunami Hazard map• Tsunami Exposure –

Population map (day-, night time)

• Tsunami Vulnerability map

• Tsunami Risk map

Availability of tsunami risk assessment products sub-national scale 1 : 100 000

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Warning chain

21Warning chain

Shelter (Banda Aceh)

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Hazard Mapping“Low Tech – Method”

Science meets Politics Padang Consultative

Group

Warning ChainLink national - local

Decision Making“Local 24 / 7”

SOPsWarning Dissemination

Dissemination Technology

Local networks, FM-RDS

Evacuation PlanningBased on Risk Analysis

Awareness MaterialsReader, Comics, Poster

TrainingsWorkshops, DAPS

ChecklistAssessment, planning,

monitoring

1 23 4

Contingency PlanningPart of multi hazard approach

Last Mile Capacity DevelopmentCivil Protection

Tsunami early warning timeline for near field tsunamis

T1

T2

T5

T4

T7

T3

<5min

10-60 min

> 90 min

T6

T0

Local government: receiving warning, decision making whether to call for

evacuation and providing guidance to community at risk

Community: reaction to the warning from BMKG & guidance from local

government(has to be done very quick as waves from

local tsunamis arrive within short time)

Reac

tion

in a

ffect

ed a

reas

Community: reaction to ground shaking Earthquake

First Warning

Estimation of the threat

Warning 1EQ parameter & tsunami potential and if available estimation of the threat: •Major Warning•Warning•Advisory•No threat

Warning 2Update EQ parameter, warning levels and estimated times of arrival (ETA)

Tsun

ami S

cena

rios

Update Estimation of the threat

First Observation

End of threat

Second Observation

Further update (if any)

Third Observation

Warning 3.1Updated EQ parameter, tsunami observation and updated warning levels

Warning 3.2

Warning 3.3

Warning 4

Tide

gau

ge, B

uoy,

GPS

T0 – T4 = Critical time

Further update (if any)

Tsunami Wave 1Tsunami Wave 1

Tsunami Wave 2Tsunami Wave 2

Tsunami Wave 3Tsunami Wave 3

. . . . . . . .

Seis

mic

Update on EQ parameter and warning level

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Evacuation maps

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Public information

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Compilation of Project Outputs and Experiences

• Background information• Checklist• Tools / Manuals / Guidelines• Fact Sheets• Further Resources

• Bilingual / hard copy and digital / web-based

www.gitews.org/tsunami-kit

Th

e P

roje

ct

Docu

men

tati

on

TSUNAMIKit

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Aim: Implementation into the National Strategy,organizational and legal boundary conditions

Instruments:• Legal autorization as national task and duty,

availability of institutional budgets• Clear definition of mandates for all agencies,

institutions and bodies: national, governmental level, local

• National Law 24/2007• New Disastermanagement Agency BNPB (2008)• Early Warning-Mandate for BMKG („BMKG“-Law, 2009)

Organization and Administration

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Conclusion

Tsunami Early warning improved remarkably in many regions

GPS improves the information situation in the early stage after an Earth quake for near field cases

There is still a long way to go to improve Early warning• More relevant information needed in the early stage after an

Earth quake especially in the near field case: GPS, near real time inversion for slip distribution

• Risk assessment including preparedness of local communities