国際的な津波リスク評価−これまでの研究と今後の課題−
サッパシー アナワット

東北大学 災害科学国際研究所 寄附研究部門
地震津波リスク研究部門（東京海上日動）
第６回 IRIDeS 金曜フォーラム
２０１２年１１月３０日
1

研究部門の紹介 寄附研究部門
地震津波リスク研究部門（東京海上日動）
地震津波リスク研究部門（東京海上日動）
2012年4月、東京海上日動火災保険株式会社の寄附を受けて、東北大学災害科学国際研究所（IRIDeS）内に「地震・津波リスク研究分野」が開設されました。当研究部門では、東日本大震災の被害実態やこれまでの巨大地震における津波（波高分布や到達時間）を評価し、国内外における社会での脆弱性や防災力を考慮した被害推定や発生確率を加えた津波リスクの評価手法を研究します。また防災・減災に関するセミナー開催や防災教育ツールの開発等を通じて、得られた知見を広く社会に提供していきます。

目的
地震津波リスクに関する研究を展開するため、国内外での地震による津波の評価（波高分布や到達時間）をベースに、社会での脆弱性や防災力を考慮した被害を推定し、さらには、発生確率を加えた総合的なリスクの評価手法について検討を行います。


研究活動と内容
地震津波リスクについて共同で研究を実施
国内外での津波リスクデータの収集と整理
東日本大震災での被害実態と復興関係の情報収集と整理
各種シンポジウム・啓発活動の実施

メンバー
今村文彦

教授
サッパシー・アナワット 准教授
安倍 祥助手福谷 陽助手保田 真理助手
http://www.tsunami.civil.tohoku.ac.jp/hokusai3/J/irides_etrisk/index_j.html

2Self Introduction
Birth place: Bangkok, Thailand (29)
Education background• 2001 – 2005 B. Eng. (Civil Eng.) Chulalongkorn University• 2005 – 2007 M. Eng. (Water Eng.) Asian Institute of Technology (AIT)• 2007 – 2010 Ph. D. (Tsunami Eng.) Tohoku University
Working experience• 2010 – 2012 Research Fellow, Willis Research Network (WRN)• 2012 – present Associate Professor, IRIDeS, Tohoku university
Experienced two great disasters
The Great East Japan tsunami in March 2011 andThe Great Thailand flood in October 2011

3International collaboration: Tsunami survey guidance
DateOrganization

Location

3 October 2012

Profs from UK universities and UK Embassy in Japan

Onagawa, Ishinomaki and Sendai

21 September 2012

APRU Symposium participantsOnagawa, Ishinomaki and Sendai

23 August 2012

Ken Kornberg

Sendai area

23 August 2012AIT Extensions (Disaster prevention training course)

Sendai area

25 July 2012JICA training-Integrated disaster prevention in central Asia-Caucasus

Sendai area

2 July 2012

Thailand’s Minister of Information and Communication Technology

Sendai area

19 June 2012

Dr. Ingrid Charvet, UCL, the Royal Thai Embassy in Tokyo and Thai TV 9 channel

Sendai area

10 May 2012

Dr. Carl Harbitz (Norwegian Geotechnical Institute (NGI)

Sendai area

26 March 2012

Thai Flood experts

Onagawa, Ishinomaki and Sendai

16 March 2012

SATREPS (JST-JICA) tsunami project

Onagawa, Ishinomaki and Sendai

12 March 2012

Dr. Nick Wigginton (Science Editor)

Sendai25 January 2012

Dr. Brain E. Tucker (GeoHazards International)

Sendai area

22 January 2012

KIP (Knowledge Investment Programs)

Sendai area

18 January 2012

Prof. Emile Okal (Northwestern University)

Sendai area

15 January 2012

Prof. Perwitt (University of Arizona) and Prof. Kirby (USGS)

Sendai area

21 November 2011

Prof. Iwata Shuichi (University of Tokyo)

Sendai area

9 November 2011

WRN

Miyako to Kuji

2 November 2011

JST National Innovation Coordinator Forum in Sendai

Ishinomaki city and Sendai city

22 October 2011

Dr. Veronica Cedillos (GeoHazards International)

Sendai area

19 October 2011

Alfred P. Sloan Foundation and Census of marine life

Sendai area

28-29 September 2011

Dr. James D. Goltz (California Emergency Management Agency) and Dr. Iuchi Kanako (The world bank)Sendai area and Onagawa

7 September 2011

WRNOnagawa to Watari

2-3 September 2011

Swiss Re

Minami-Sanriku to Sendai airport

25 July 2011

World Bank (GFDRR)-JICA

Ishinomaki to Sendai Port

30 May – 2 June 2011

Prof. Ahmet Yalciner teamTaro to Kesennuma

29 May 2011

JST-JICA and RISTEK Indonesia

Sendai airport to Sendai port

4

Visited University College London (UCL)
Key person
Dr. Tiziana Rossetto, Director(Earthquake Engineering)
Dr. Ian Eames (Civil Engineering)
Dr. Ingrid Charvet (Civil Engineering)
Dr. Tristan Robinson (Mathematics)
Dr. Ioanna Loannou (Earthquake Engineering)
Dr. Anna Mason (Earthquake Engineering)

EPICentre (Earthquake and People Interaction Centre)
http://www.epicentreonline.com/

The Leverhulme Trust – International network grant
http://www.leverhulme.ac.uk/
Quantification of uncertainties in tsunami models
from sources to impacts
University College Dublin (Ireland), GNS Science (NewZealand), Durham University (UK), Tohoku University(Japan), University of New Mexico (USA) and University
College London (UK)Key person
Prof. Peter Sammonds, Director (Earth Science)
Dr. Rosanna Smith, Deputy Director (Earth Science)Prof. David Alexander (Disaster Science)
Dr. Serge Guillas (Statistical Science)
Dr. Simon Day (Earth Science)
Dr. Joanna Faure Walker (Earth Science)

IRDR (Institute for Disaster Risk Reduction)
http://www.ucl.ac.uk/rdr/

5

Tsunami Generation
Tsunami Propagation
Tsunami Inundation(Human and Building)
6

Tsunamigenic ratio in the Pacific Ocean
Earthquake events and tsunamigenic zone in the Pacific Ocean
地域Regions

Abbrev.

略記

New Zealand–Tonga

NZT

New Guinea–Solomon

NGS

Indonesia

IND1

Philippines

PHIJapanJAP

Kuril–KamchatkaK–K

Alaska–Aleutians

A–A

Central America

CAM

South AmericaSAM

 This study considers the NGDC database which contains earthquake event of 200 B.C. to present (from year-193 to 2010) and separated into 4 different periods (pre-instrumental (prior 1900), early instrumental (19001962), instrumental (1963-1990) and modern instrumental (1991-present).
 The earthquake event excludes an event that the epicenter located longer 50 km from a shoreline.
 The Tsunamigenic Rate (TR) is calculated from earthquake event of the magnitude varies from 5.0 to 9.0,
focal depth is as deep as 200 km and sea depth is as deep as 7,000 m.
 The Pacific Ocean is geographically divided into 9 regions namely, New Zealand–Tonga (NZT), New
Guinea–Solomon (NGS), Indonesia (IND), Philippines (PHI), Japan (JAP), Kuril–Kamchatka (K–K), Alaska–
7
Aleutians (A–A), Central America (CAM) and South America (SAM).

Tsunamigenic ratio for each region
NGS

IND

PHI

JAP

K_K

A_A

CAM

SAM

NZT

11

0.8

0.8

Tsunamigenic Rate

Tsunamigenic Rate

NZT

0.60.400NZTIND

7Earthquake magnitude

NGSPHIJAP

K_K

89PHI

JAP

K_K

A_A

CAM

SAM

0.40.26IND

0.60.25NGS0100200300

400500

Focal depth (km)
A_A

CAM

SAM

Tsunamigenic Rate

10.8

 Earthquake magnitude
0.6
Great earthquake magnitude  high possibility oftsunami occurrence (Generally > 7.0)
0.4
 Focal depth
0.2
Shallow focal depth  high possibility of tsunami
0occurrence (Generally < 100 km)
1
10100
1000
10000
 Sea depth
Sea depth (m)Deep sea depth  high possibility of tsunami
Suppasri, A., Imamura, F. and Koshimura, S. (2012) Tsunamigenic
Ratio of the Pacific Ocean Earthquakes and a proposal for a Tsunami
occurrence (Generally > 1,000 m)
Index, Natural Hazards and Earth System Sciences, 12(1), 175–185

8

Tsunami Generation
Tsunami Propagation
Tsunami Inundation(Human and Building)9Effect of fault rupture velocity on tsunami propagation
Examples of the 2004 Indian Ocean tsunami•DCRC (2007): Static model•Hirata (2006) : Dynamic model, Vr = 0.7 km/s
•Fujii (2007) :Dynamic model, Vr = 1.0 km/s
•Tanioka (2006) : Dynamic model, Vr = 1.7 km/s
•Piatanesi (2007) : Dynamic model, Vr = 2.0 km/s

Suppasri, A., Imamura, F. and Koshimura, S. (2010) Effect of therupture velocity of fault motion, ocean current and initial sea levelon the transoceanic propagation of tsunami, Coastal Engineering
Journal, 52(2), 107–132

HirataFujii

TaniokaPiatanesi

DCRC
10

Effect of fault rupture velocity on tsunami propagation
Effect to tsunami arrival time at each tide gauge
station around Indian Ocean~ 21% or 27 minutes~ 3% or 5 minutes~ 11% or 13 minutes
11

Numerical experiment:
Effect on tsunami amplitude and arrival time

Location for output calculation

Fault length= 1,000 km
Distance btw 2 points= 500km
Slower velocity & Deeper sea
 Strong effect
HD/HS

25

13

140
25

60
80
13 1

4.0
3.0
2.0
1.0
0.0
0

20

TD/TS

100
VR/C

Non-dimensional VR/C 2.0
VR = Rupture velocity (m/s)
1.5
C = Tsunami velocity= (gH)1/2 (m/s)
1.0g = Gravitational
0.5
acceleration (m/s2)
H = Sea depth (m)0.0Simple fault with flat bottom
depth = 4000 m

Velocity = 1.0 km/s (1.0 ~ 2.5)
depth = 4000 m (4000 ~ 100)

Dynamic effect can be
negligible if VR/C > 40

02040

60

80

100
VR/C

12

Tsunami Generation
Tsunami Propagation
Tsunami Inundation(Human and Building)
13

Tsunami hazard map for different recurrence
Tsunami hazard map for different
recurrence (Magnitude)
Total = 400 cases

Tsunami hazard map fromearthquake M = 9.0
M = 9.0
Combined hazard map
For one recurrence (Magnitude)

M = 9.3(1,000 km)
M = 9.0(600 km)
M = 8.9(500 km)
M = 8.7(400 km)
M = 8.5(300 km)
M = 8.2(200 km)
M = 7.6(100 km)

14Indian Ocean tsunami hazard map for M=9.0
IRN
ARE

PAK
BGD

OMN

IND

MMR
THA
PHL

LKA
MDVMYS
IDN

SYC
TMP

MUSAUS

REU

15

Risk assessment for coastal population
Country’s tsunami risk level

THAILAND

Population
per km2
Height (m) Score< 0.125
1< 0.25
2< 0.5
3<14<25<46<87< 168< 329> 32
10=1112345678910<522468101214161820< 10336912151821242730< 50
448121620
2428
323640< 100
551015202530
3540
45
50

< 500
6612182430
3642
48
54
60

< 1,000
771421
2835
42
49
56
63
70

< 5,000
88162432
404856
647280Mw

Tr (yr)

Max.
level

Avg.
level

9.3

600

81

21

9.0

450

64

18

8.9

400

63

168.7

325

54

148.5

250

45

118.2

170

35

87.6

65

18

4

< 10,0009918273645
54
63
72
81
90

> 10,000
1010203040 Calculation method of
50 “Risk level”
60  Exponential scale
70  Score range 1 - 1080  Max. level = 100
90  Easy to understand100

16Tsunami risk map for Mw 9.0 earthquake

Tsunami height

Exposure population

Example forone country

Tsunami risk
17

Rough estimation of number of casualty
100

1771 Meiwa
1896 Meiji

Fatality ratio (%)

101933 Showa
1944 Tonankai
1946 Nankai

11960 Chile
1993 Okushiri

0.1

2011 Tohoku Ria
2011 Tohoku Plain

0.01
1

10Maximum tsunami height (m)100Tsunami fatality ratio
Casualty20041,000,000BurmaAndaman

SumatraJavaMakran

Nearly 100,000 in Makran andJava.
About 30,000 for Andaman.
Nearly 10,000 for Burma andSumatra.

100,000
10,0001,000100101110Maximum simulated tsunami height (m)100

Estimation of possible casualty
in the Indian Ocean

18

Tsunami Generation
Tsunami Propagation
Tsunami Inundation(Human and Building)19

Criteria for structural destruction by tsunami
Tsunami event
Multiple events[Shuto, 1993 andMatsutomi and Harada, 2010]

Location

FrameWood

VariousConcrete blockRC

Wood/bamboo

2006 Java tsunami[Reese et al., 2007]

South Java,Indonesia

Brick traditional

Brick with RC column

RC with brick wallWood
2004 Indian Ocean tsunami[Ruangrassamee et al., 2006 andSuppasri et al., 2011]

SouthernThailand

2011 East Japan tsunami[Suppasri et al.., 2012]

Miyagiprefecture,Japan

RC with brick wall

Wood

Damage description as a function of inundation depth< 1.5 m: moderate damage< 2.0 m: severe damage< 3.0 m: moderate damage< 7.0 m: severe damage< 1 m: light to moderate damage
1.5 – 2.0 m: 70% destroyed, 30% lightly to heavily damaged but
repairable> 2 m: total destruction< 1 m: light to moderate damage
1.5 – 2.0 m: 70% destroyed, 30% lightly to heavily damaged butrepairable> 2 m: some houses remained but not repairable< 1 m: minor damage only
1.5 – 2.0 m: light to moderate damage (repairable)
3.0 – 4.0 m: serious damage but probably repairable< 1 m: zero to light damage
1.5 – 2.0 m: light to moderate damage (repairable)
3.0 – 4.0 m: moderate damage but repairable< 1.5 m: no damage up to damage to secondary members only
< 2.5 m: damage to some primary members up to collapse> 3 m: collapse< 1.0 m: no damage
1.0 – 2.0 m: no damage up to damage to secondary members only
2.0 – 3.0 m: damage to secondary up to some primary members> 3.0 m: damage to some primary members up to collapse> 7.0 m: collapse> 2.5 m: minor damage> 3.0 m: moderate damage> 4.0 m: major damage> 4.5 m: completely damage

20

Level 1: Roof and wall

Developing fragility curves
Field survey VS Simulation + Satellite image
Only inundation depthMulti damage level
Small area but high accuracy

Level 2: Beam and column

Include velocity, force
Only for washed away
Large area but accuracy?
Koshimura et al. (2009), etc.

Level 3: foundation

Destroyed

Survived

1000
800
600
400
200

Inundation depth (m)

8.2

5.6

5.1

4.8

4.5

4.2

3.9

3.5

3.1

2.8

2.4

2.1

1.7

1.3

1.0

0.6

00.2

Number of building

120021Global tsunami fragility curves

Thailand

Tohoku , Japan

Suppasri,
Koshimuraet al. (2010)

Koshimura et al. (2012)
Yanagisawa et al. (2012)
Suppasri et al. (2012)

Okushiri, Japan
Koshimura et al. (2009)

ChileMas, Koshimura,Suppasri et al. (2012)

Indonesia

American Samoa

Koshimura et al.
(2009)

Gokon and Koshimura(2011)

22

Tsunami fragility curves based on the 2011 tsunami data
Minor damage

Inundation depth measured at 150 wooden
houses in Ishinomaki and Sendai Plain

VERSION 1

Moderate damage

Major damage

Complete damage

Inundation depth and number of damaged house(Blue: Not damage and Red: Damaged)
Suppasri, A., Mas, E., Koshimura, S., Imai, K., Harada, K. and Imamura, F.
(2012) Developing tsunami fragility curves from the surveyed data of the 2011
Great East Japan tsunami in Sendai and Ishinomaki Plains, Coastal
Engineering Journal, 54(1), 1250008

23

Classified building material and no. of storyRC1, 2 and > 3 stories

Wood
1, 2 and > 3 stories

VERSION 2
About 250,000 buildings in MLIT database but no detail for each building
http://www.mlit.go.jp/toshi/toshi-hukkou-arkaibu.html

RC

Steel

Wood

Masonry

Suppasri, A., Mas, E., Charvet, I., Gunasekera, R., Imai, K., Fukutani, Y., Abe, Y. andImamura, F. (2012) Building damage characteristics based on surveyed data and fragility
curves of the 2011 Great East Japan tsunami, Natural Hazards, (published online)24

Problems to be solved in the future
Tsunami generation: Need to consider more on earthquake fault parameter such as dip,rake and slip and apply more statistical parameters
Tsunami propagation: Need to apply a Probabilistic Tsunami Hazard Analysis (PTHA)
Tsunami inundation
Impact to human: Need to further discuss on human behavior effect and applying tsunami
evacuation model based on results from questionnaire surveys
Impact to building: Need to consider more on impact from different coastal topography,building function, construction year, surrounding environment and floating debris
Uncertainties from effect of rupture velocity(Fukutani et al., 2012)

Evacuation model applied to Thailand(Erick and Suppasri et al, 2012)25

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