This document analyzes mortality circumstances from the 2011 Great East Japan Earthquake. It reports that over 16,000 people died, with deaths highly concentrated in coastal areas flooded by the tsunami. The analysis found that mortality rates increased sharply with age, particularly for those over 60, and were highest in areas washed away or with deep flooding. Many deaths occurred at altitudes under 6 meters. The elderly were most vulnerable, and more data could allow a more detailed analysis of factors influencing mortality risks.

1. 15th WCEE in Lisbon, 24-28 September 2012 1
Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
AN ANALYSIS OF THE CIRCUMSTANCES
OF DEATH
IN THE 2011 GREAT EAST JAPAN EARTHQUAKE
M. Koyama, A. Yoshimura & J. Kiyono
Graduate School of Engineering Kyoto University,
Japan
N. Ishii
Building Research Institute, Japan
S. Mitani & S. Koh
Graduate School of Medicine Kyoto University, Japan
京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット

2. Introduction
2 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 Damage summary of The Great East Japan
Earthquake of March 11, 2011
Tsunami height map
 Death1) : 16,278 by JMA
 Missing1) : 2,994
 Totally collapse1) : 129,198
 Washed away houses2) : ~78,000
 Purpose of this study
 We review the circumstances of victims at the time of
death in the damaged area and present a detailed
analysis of mortality in the tsunami inundation areas.
1) FDMA : Situation Report No.145
2) MLIT : Summary of the Field Survey on The 2011 off the Pacific coast of Tohoku
Earthquake, No.1. 京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット

3. Data sources
3 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 FDMA : Situation reports
 Municipalitylevel damage numbers that are
casualty, building damage, fire, etc…
 Prefectural Polices : Casualty information
 Thebody-identification information of the
Iwate, Miyagi and Fukushima prefectural police
 Geographical inundation digital map
 Inundation area and washed away area map
 500m grid population data of the census
京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット

4. Fatality rate by age and gender
4 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 The death rates of those in the over 60 age
classes are sharply higher. Furthermore, as
age increase, the death rate of males
increases.
1.40%
1.20% male
female
1.00%
fatality rate
0.80%
0.60%
0.40%
0.20%
0.00%
京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット
Age

5. Spatial distribution of death
5 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 Deaths are
concentrated in costal
inundation areas of the
tsunami.
 The most of the deaths
Death
occurred in the Washed-away Area
washed-away areas. Inundation Area
京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット

6. Fatality rate of inundation situation
6 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 The death rates in the age classes of those
over 60 were exceptionally high.
20.00%
18.00% Totally inundation area
16.00%
fatality rate
14.00% Washed away area
12.00%
10.00%
Inundation Area without
8.00% washed away area
6.00%
4.00%
2.00%
0.00%
0-4 old
85 and over
5-9 old
15- 19 old
70-74 old
10-14 old
20-24 old
25-29 old
30-34 old
35-39 old
40-44 old
45-49 old
50-54 old
55-59 old
60-64 old
65-69 old
75-79 old
80-84 old
京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット
Age groups

7. Death toll by inundation situation
7 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 Many deaths occurred at altitudes less
than 11 meters, and especially of less
than 6 meters
400
350 Totally inundation area
300 Washed away area
250
Death toll
Inunadation area without
200
washed away area
150
100
50
0
Elevation (m)
京都大学大学院 工学研究科・医学研究科 安寧の都市ユニット

8. Conclusion
8 Unit for Liveable Cities, Graduate School of Engineering/Medicine, KYOTO UNIVERSITY
 We clarified the relationship between
inundation/washed-away areas and the
situations in which death occurred.
 In particular, from the age-classified death
rates, we addressed the issue of elderly
mortality.
 If more important information becomes, a more
concrete analysis can be made.
 Spatial inundation depths, the location of people
at the time of the tsunami’s arrival, and the
construction dates, structures,安寧の都市ユニット
京都大学大学院 工学研究科・医学研究科
and number of