SDR Report No.5E (2015/06/05)

Some Studies on the 2011 off the Pacific coast of Tohoku Earthquakewith a central focus on the strong motion
Earthquake Strong Motion, Alarm Issuing Situation, Strong Motion Observationand so on.
Yutaka Nakamura
System and Data Research Co., Ltd.
Visiting Professor of Tokyo Institute of Technology (at that time)

1. Foreword
Ground motion of the 2011 Tohoku Earthquake on March 11, 2011, is quite difference from thepast experienced one such as the earthquake motion increasing gradually, large motion
repeatedly attacking after reaching its peak, or incredible long duration time.
Here, the timings of the various alarms issued for the earthquake (including tsunami warning),
are shown on the graph indicating the temporal or special changes of the seismic intensity, andsome topics are picked up for the discussion.

2. Earthquake Parameters
Table 1 shows the estimated earthquake parameters of this earthquake by the Japan
Meteorological Agency, JMA, and the US Geological Survey USGS.
JMA says that the destruction started about 120 km east off of the Oshika peninsula with a depthof about 24km.
Table 1 Earthquake Parameters by JMA and USGS
Organization

Origin time

Magnitude

2011/03/11

Epicenter

Depth

LatitudeLongitude

(km)

JMA

14:46:18.1(JST)Mw9.0

38.103°N

142.860°E

24

JMA (preliminary)

14:46(apl.)

Mjma7.938.0°N

142.9°E

10

USGS

05:46:23(UTC)Mw9.0

38.322°N

142.369°E

32

1

3. Expression Situation of Seismic Intensity and so on(1) Space-time distribution of realtime seismic intensity
Figure 1 shows the variation of the local realtime seismic intensity derived from the strong
motion records of K-NET and other seismometers. The horizontal axis shows the difference of©SDR: 2011.4.7., modified at 5.19 and 7.3

7.0

300
14:51:00

100

240

MisawaMorioka

Tsukidate

0200

Aomori

Yamabiko #144 Max

300

400

229s: Emergency Warning via NHK
226s: Tsunami Warning by JMA via NHK

14:50:00

180
14:49:00

120

137s: End of EEW via NHK…

Time in seconds from 2011/03/11,14:46:26 JST

14:52:00-100

Hayate #27-200

Yamabiko #61-300

Fukushima
Sendai3.0
360-400

Tsukuba
Mito

4.0

Shinjuku

5.0

Warning Area
①Miyagi, Iwate,
Fukushima but
Aizu, south inlandof Akita andYamagata but
Shounai andOkitama; JMA#4②Add. Aizu,Shonai,
Okitama, Ibaraki,
coast of Akita,
Sampachi-Kamikita
of Aomori, Kaetsu of
Niigata, north-eastof Chiba and southof Saitama; JMA#7③Add. Tochigi andeast of Kanagawa;JMA#10④Add. the rest of
Aomori, Chuuetsu,
south of Gumma,
north of Saitama,
the rest of Akita,
north-west of Chiba
and the 23 wards ofTokyo; JMA#12

6.0
Yokohama

Realtime Intensity
RImaxRimax

epicentral distance and the vertical axis shows the elapsed seconds from March 11, 2011

14:48:00

④79s

60

37s:
EEW of②36s
JRShinkansen①2 3 s: EEW o f JMA③44s

14:47:00

2 8 s: EEW via NHK

0-400

20s: First EEW of FREQL-300

south side

-200

-100

0

100

200

Epicentral Distancein km minus
Difference
between Epic.Dis.
and127km
127km

300

RI
Peak
Max
6.5
6.0
5.5
5.0
4.5
4.0
3.5
2.5
2.0
1.5
0.5
0.0
P-arrival

400

north side

Figure1 1P-wave
P-wavearrivalWarning
Realtime
Intensity
Figurearrivaltime,time,
Warningtimes,times,
Realtime
Seismic Seismic
Intensity andetc. forandthe etc.
2011foroffthethe2011 off the Pacific coast of Tohoku Earthquake

Pacific coast of Tohoku Earthquake2

14:46:26 JST, start time of the first recorded waveform of Oshika K-NET station. The differenceof epicentral distance was derived as a difference from the epicentral distance of each station
based on the primary epicenter by JMA to the epicenter of 127km around K-NET Oshika station(MYG011) at Oshika peninsula. Plus and minus signs correspond to northern and southern sidefor Oshika peninsula, respectively. Colored circles correspond to the realtime seismic intensity
or the expression time of peak or maximum value of it, as shown in the legend. The upper partof this figure shows the maximum value distribution of realtime seismic intensity. The circled
number in this figure shows the time JMA issued the earthquake early warning, EEW. The mark1 is the issued time of EEW by JMA for the public, 14:46:49 <23>. Here the number in < >○shows the elapsed seconds from 2011/03/11 14:46:26. In addition, with each extension of thearea where the seismic intensity is estimated over 3 or 4 based on the EEW by JMA for
1 , this figure shows this area with issued time of EEW.
advanced users during 60 seconds after ○1 , and the EEW by JMA for
EEW by JMA for public was the fourth report and corresponds to ○public is issued once for one event in principle. Thereafter, ○2, ○3 and ○
4 correspond to the7th, 10th and 12nd report of the EEW by JMA, respectively. In addition, this figure shows thetime displaying the EEW on the analog TV screen over the NHK program at 14:46:54 <28> anddisappearing at 14:48:43 <137>. Also this figure shows the time of issuing Major Tsunami
Warning at 14:50:12 <226> and the time receiving the emergency warning with sound signal at
14:50:15 <229>. Furthermore, this figure indicates the time issuing the early warning for the
Shinkansen trains at 14:47:03 <37> based on the newspapers. For comparison with this situation,
the results of the simulation issuing alarm using FREQL, for example the fastest alarm time was
14:46:46 <20> using the strong motion record at K-NET Kitakami station, MYG008, are shown.
The actual P wave alarm was issued at 14:46:52 <26> from FREQL installed on the quite hardground around the base of Oshika peninsula. It is confirmed that this result agrees with that ofsimulation with recorded waveform.
Figure 1 is modified from Figure 7 of SDR Report No. 3, only in Japanese, with correcting
misunderstandings of the target area issued the EEW by JMA and adding the informed time ofissuing EEW and Major Tsunami Warning on NHK TV program, announced time of emergency
warning and issued time of early warning for Tohoku Shinkansen train.
On the following sections, some items are discussed based on this figure.
(2) On the realtime intensity
The real-time seismic intensity RI is a unique index of SDR (Patent No. 3,764,943) redefinedand named in 2003 after considering the new earthquake motion index DI proposed in 1998. RI
3

is internationally recognized as referred at international conferences. This index is defined ascommon logarithm of power, inner product of the acceleration vector and velocity vector, ofground motion acting per unit mass adding constant. It can be calculated in realtime withphysical meaning in contrast to seismic intensity of JMA proceeded artificially from recorded
waveform of 60 seconds (JMA Notification No. 4), and its maximum value fits to the
instrumental seismic intensity of JMA.

4. Earthquake Motion(1) Spatial distribution and time-series behavior of realtime intensity
According to the maximum value distribution of realtime seismic intensity on upper Figure 1,
there are two peaks at around 150km of the epicentral distance difference of the south side andat around 50km of the epicentral distance difference of north side. The distribution slightly
biased on the south side as a whole and seismic intensity of the Kanto region in south side isgreater than that of the northern Tohoku region.
Based on the temporal distribution, the expression time of the each seismic intensity levelroughly became late in proportion to the epicenter distance difference and that of the maximum
earthquake motion showed in same manner in northern Tohoku region. In contrast to this, thatin Kanto region assumes a slightly different aspect. Although the P-wave has been reached early,
after reaching the seismic intensity 2, the expression time of the each seismic intensity level
became later and the maximum seismic intensity appeared much later. In addition, a clear
discontinuity is observed at the time of maximum seismic intensity expression in the area of thesouth side of the epicentral distance difference 100km. The peak of the seismic intensity
corresponding to the first epicenter is not clear and hard to recognize in Kanto region. It seems
to be the reason that the expression of the maximum seismic intensity became quite late. Overall
the duration time has become strangely long. The duration time over seismic intensity 4 isaround 1.5 minutes to over 2 minutes in the northern area with more than 100km of theepicentral distance difference, over 2.5 minutes in the area with a central focus on Sendai within
100km of the epicentral distance difference and reaching 3 to 3.5 minutes in the southern area inthis figure. Since seismic intensity that can sense a human body is generally one or more, ittakes even long time to decrease below weak unfelt vibration.
There are two clear peaks on the change of the realtime intensity in the area with a central focus
4on Sendai, largely from Fukushima to Morioka. The time interval of the two peaks is about 50
seconds in the Oshika Peninsula in the area of the center, about 45 seconds in the south, andabout 35 seconds in the north. Additionally, although the second peak mainly becomes the
maximum value, the first peaks sometimes gives the maximum value. This situation seems toreflect the location or size relation of the first and next epicenter. It is not clear but thesecondary destruction seems to locate in northern side of the first destruction starting point.
According the video (http://www.sdr.co.jp/110311tohoku-eq/20110311tohoku.html) to visualize
the wave propagation situation using realtime intensity, there are at least three main destructions.
The first one progressed toward to a little bit to the north from the starting point, the epicenter,the second one started at slightly southern off of Sendai 50 seconds after the first one, and thenthe last destruction started seemed to progress from beneath the seabed at off Fukushima
prefecture towards to Chiba prefecture, southern side, more 50 seconds later. As a result, it isestimated that northern region is less affected by the third destruction and because Kanto region
is more affected by the latter destruction, the earthquake motion was gradually increased and thelarge motion continued more than three minutes.
To make clear more that above mentioned, a paste-up view of realtime intensity of almost
collinear K-NET station was drawn as Figure 2. This figure has same meanings of Figure 6 on
42

41

41

40

40

39

39
North Latitude

42

38

38

37

37

36

36

35

35

34

34
139

140

141

142

143 0

60

120
180
240
Time in seconds from 2011/03/11, 14:46:26

300

Figure 2 Past-up of Changing of Realtime Seismic Intensities at sites along NS line
Figure 2 Past -up of Changing of Realtime Seismic Intensities at sites along NS line shown in the left
shown in the left figure for the 311 Earthquake
figure for the 311 Earthquake

5360

SDR Report No. 3, only in Japanese, and can be an improved version because of representing
the latitude corresponding to the peak of the travel-time curve more clearly. The vertical axis
indicates the value that the latitude of each station adding the real-time seismic intensity × 0.15.
Changes of realtime intensity are expressed as a relief. Arrivals of the wave are shown as anedge of the relief in red and some phases can be confirmed as continuous mountains inyellow-green or valleys in pink. According to this figure, there are four sets of lines that can berecognized as a travel-time curve and the actual latitude around the peak of the yellow-green
hyperbolic curve is the value about 0.8 (= 5 × 0.15) subtracting from the value of the verticalaxis because the yellow-green line corresponds to the line about seismic intensity 5. That is, thelatitude of the first epicenter is off Ofunato around 39°N, the second one after 45 seconds is off
Sendai around 38.2°N, the third one more after 24 seconds is off Iwaki around 37°N and the last
one more after 15 seconds is off Takahagi around 36.7°N. It is able to grasp roughly where themain destructions occurred from this figure.
(2) Problem of the strong motion records
Figure 3 shows a recorded waveform of K-NET MYG004 Tsukidate station at the time of the2011 off the Pacific coast of Tohoku Earthquake with JMA seismic intensity 7 (realtime
intensity 6.6). The waveform in this figure shows unusual behavior that the acceleration locus
on the NS-UD plane draws a figure-of-eight in the frequency of 4-6 Hz. Especially, the sectionof one second around the maximum acceleration shows abnormal behavior that the basement
block of the strong motion seismometer buried in the ground is estimated hitting surrounding
ground and moving like dancing, from the displacement locus obtained by double integration in
Figure 4 with the predominant frequency of around 4 Hz. This means that the response of thebasement block was recorded instead of that of the ground motion. Therefore, seismic
waveforms of Tsukidate station with the highest seismic intensity of the 3.11 Earthquake cannot
be compared with the damage situation around the station. The record of K-NET or KiK-net
sometimes seems to reflect strongly the influence of the damage for the observation
environment as the station or the basement, pointed with a “realistic model to reproduce theextreme acceleration waveform recorded at KiK-net IWTH25 station during the 2008
Iwate-Miyagi Nairiku earthquake” (Omachi et al.: Estimated cause of extreme acceleration
records at the KiK-net IWTH25 station during the 2008 Iwate-Miyagi Nairiku earthquake,Japan, Journal of JAEE, Vol. 11, No. 1, 2011.). It seems that this kind of problem has become
pronounced especially after obtaining large earthquake motion. It may get to the time forgrasping the dynamic characteristics of the strong motion observation environment including
the station. Proper improvement is expected with grasping the problems of the current strong6

motion observation environment using the large shaking table of NIED collaborating with JMA,
universities or other organizations. It is also expected to indicate clearly the dynamic
3000

MYG004Tsukidate

2000

NS component

1000
0
-1000

UD component

-2000
-3000
0

50

100

150

2000

2000

1500

XZ: 20-30sec.
1500

1000

1000

500

500

0

0

-500

-500

-1000

-1000

-1500
2000-3000

-2000

-1000

0

1000

2000

3000

-1500
-3000
2000
4000

1500

XZ: 30-45sec.
1500

1000

1000

500

500

0

0

-500

-500

-1000

-1000

-1500
2000-3000

-2000

-1000

0

1000

2000

3000

-1500
4000
2000
-3000

1500

XZ: 45-60sec.
1500

1000

1000

500

500

0

0

-500

-500

-1000

-1000

-1500
2000
-3000

-2000

-1000

0

1000

2000

3000

-1500
2000
-3000
4000

250

-2000

-1000

0

1000

1000

500

500

0

0

-500

-500

-1000

-1000

-2000

-1000

0

1000

2000

3000

-1500
－3000
4000
-3000

2000

3000

-2000

-1000

0

1000

2000

3000

4000

XZ: 95-100sec.

-2000

-1000

0

1000

2000

3000

4000

XZ: 100-130sec.

-2000

-1000

0

1000

2000

3000

Figure 33 Acceleration
Acceleration Waveforms
and Locus
Gal on in
theGalNS-UDplaneNS-UD
at K-NET
Tsukidate
FigureWaveforms
andinLocus
on theplane
at
MYG004for the 311MYG004
Earthquakefor the 311 Earthquake
K-NET
Tsukidate7

4000

XZ: 80-95sec.

1500

1000

300

XZ: 70-80sec.

XZ: 60-70sec.

1500

-1500
-3000

200

4000

characteristics of the observation system changing with input, in order to properly correct thepast recorded waveforms. This is confirmed that it is basically and important issue related to thereliability of the strong motion observation data.
Figure 5 is a waveform recorded at K-NET MYG013 Sendai station and the shape shows
acceleration waveform characterized in case of a liquefaction of the foundation ground. Thus,

UD component in cm

0.5

95s

0

-0.5

-1

96s
-1.5
-6

-5.5

-5

-4.5

-4

-3.5

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

NS component in cm
Figure 4 Displacement Locus in cm on NS-UD plane for one second between 95 and 96
seconds of the waveform recorded at K-NET MYG004 Tsukidate for the 311 Earthquake
2000

Non filtered PGA in Gal

1500

NS-component

Around First Event

1000

500

0

-500

EW-component

-1000

-1500
45

50

55

60

65

Non filtered PGA in Gal

2000

Around Second Event

1500

1000

500

0

-500

-1000

-1500
95

100

105

110

115

Time in seconds after 2011/03/11,
Figure 5 Acceleration waveformof K-NET MYG013 Sendai at the time of the 311 Earthquake:
14:46:26

the amplitude near 57 seconds on the first event is diminished quickly and there are
overlapped pulse noises on the peak and on the trough, and on the second event the waveform
shows similar shape from its start8the strong motion records include not only the information of particular fault rupture process
and amplification characteristics of the surface ground, but also occasionally influence of the
distinctive vibration for individual observation system or the damage of the observation system.
It is important for performing a detailed analysis of strong motion waveform to accurately
understand the points to be remembered on the recorded situation.

5. FREQL Alarm Simulation and EEW by JMA or Early Waning System for
Shinkansen Train(1) Issuing and receiving EEW by JMA
Earthquake early warning by JMA for public issued only once in principle through thebroadcast such as NHK and mobile phones, for the areas with estimated seismic intensity 4 orover in case of an earthquake expected maximum seismic intensity over 5-. Figure 6 shows thesituation during earthquake motion on the analog TV screen of NHK program with the result of
the simulation of alarm indication of palmtop seismometer AcCo using K-NET waveform.
Alarm
Detection

Max.

First Peak

EW
NS
PGA
RI

14:48:20

MYG011 牡鹿 Oshika
Alarm
Detection

TKY007 新宿

Max.

Shinjuku
30 sec.

Hookup of the Diet deliberations

On-Site Warnings
of
AcCo
and
FREQL are usefuland faster than
EEW of JMA.

Start of JMA’s EEW on NHK analog TV, 14:46:54

Change to NHK studio from 14:48:20, already shaking

Just after strong shaking (MMI7.9) at Shinjuku,
14:49:22, the view from NHK broadcast centre

Warning Simulation
using K-NET records
Shinjuku (sequel)

TKY007 新宿 つづきOshika5HzPGA
Holding max. value

MMI=(11/7)*RI+0.5

Shinjuku
Realtime Intensity RI
Holding max. value

Continuing shaking (MMI7.1) at Shinjuku, 14:49:42

Tsunami warning by JMA on NHK analog TV, 14:50:10, after
three sec sound of the emergency warning broadcasting

Figure 6 Timing of Alarms for the 311 Earthquake using K-NET Shinjuku and Oshika records,
captured NHK TV program and etc.
9

The national broadcast of NHK TV program issues the EEW by JMA for nationwide
independently of the target area with indicating the issued area. On the other hand, in case ofmobile phones, EEW by JMA is issued to identify the target area, so called “Area Mail”. At thetime of the 3.11 Earthquake, the target area of EEW by JMA was entire Miyagi and Iwate
prefectures, Hamadori and Nakadori area of Fukushima prefecture, southern inland of Akita
prefecture and Mogami and Murakami area of Yamagata prefecture, as shown as the alarm area
1 of Figure 1.
○

Seismic intensity over 5- observed at Miyagi, Iwate and Fukushima prefectures in the area
mentioned above. However, seismic intensity over 5- also observed at wider area in a part of
Aomori prefecture, Ibaraki prefecture and bay area of Tokyo and Chiba prefecture. This meansthat the manner of alarm issuance was not appropriate. This is because the predicted seismic
intensity was considerably underestimated, and it is impossible with such predicted intensity not
only to transmit necessary alarm to necessary area but also to provide reasonable action
promptly after the earthquake. On the other hand, even in the area close to the epicenter,epicentral distance is more than 120km and P-S time is more than 15 seconds. Furthermore,since this earthquake motion increased gradually, common people had much time margin before
hit by large earthquake motion, after notification of earthquake occurrence. Probably because
this, even in case of this huge the earthquake, there was no specific report that EEW by JMA
was useful.
Time lag between issuance of EEW by JMA and reception cannot be ignored. In case of theanalogue broadcasting of NHK program, it takes about five seconds between issuance of EEW
by JMA and appearance on the screen as shown in Figure 1 or Figure 6, and it is said that thedigital broadcasting requires more. For notification to a mobile phone, the time lag from thewarning issued to the reception is said to be at least several seconds. Actually in Sendai, it was
about 5 seconds for au and 10 seconds for NTT DoCoMo. Other mobile phone careers may takesimilar time.
It has been already known that it is impossible to take a lead against large earthquake motion in
the area 30 – 50 km from the epicenter even if it is possible to receive EEW by JMA at the
moment of the earthquake occurrence, except in the case epicenter is quite deep. Taking into theconsideration that it takes 5 – 10 seconds as transfer time, it is impossible to receive EEW by
JMA before the large earthquake motion at the area of around 50 – 100 km from the epicenter,
far away from 30km, the expected damaged area of M7 class earthquake. The only huge10earthquake as the 3.11 Earthquake will suffer damage in wide area outside of this area.
In other words, it is possible for EEW by JMA to take a lead against large motion only for thearea more than 100km from the epicenter only in case of the huge earthquake with over 100 kmof the damaged area, and it may have meanings to broadcast in nationwide by NHK program.
However from this distance, it is possible for the on-site alarm to take a lead more than 12
seconds against the large motion. On the other hand, EEW by JMA makes no sense at all forM7 class earthquake because it is too late for the large motion within 50 km from the epicenter.
So Ministry of Internal Affairs and Communications forcing for local broadcasting stations to
install the receiver of EEW by JMA becomes enforcing spending the meaningless cost from theviewpoint of disaster prevention. Additionally, the predicted seismic intensity of EEW by JMA
has no accuracy available to utilize for emergency response after the earthquake. In the fact of
the response after the earthquake, it is important to install a seismometer not only issuing theearly warning but also inform the seismic information in realtime and to organize a framework
to broadcast the information immediately.
If the predicted intensity exceeds the preset level, EEW by JMA for advanced users is informed
and announced using broadcasting equipment and so on. Although JMA recommends setting thepredicted intensity 4 or more, some organizations set 3 as describing later. Because EEW by
JMA for advanced users a private line, the time lags between issuance and reception must be
short. However even in this case, it is impossible to take a lead against large earthquake motionin the damage area of M7 class earthquake. Because such EEW by JMA often priors to theearthquake motion without damage at an area far from the epicenter, a lot of people have been
misunderstood to receive the information before the large motion with damage. In this state, it isafraid that the disaster prevention countermeasures must be neglected because of exaggerated
expectations and unexpected damage suffers without any discretion.
(2) Emergency stop of Shinkansen train by EEW by JMA and the mail of EEW by JMA for
mobile phone
Although this is no concern of the 3.11 Earthquake, here I would like to introduce a case that
EEW by JMA might stop Tokaido Shinkansen train. This kind of EEW by JMA is one of themisinformation increasing significantly after the 3.11 Earthquake.
EEW by JMA for public was issued for around Kanagawa prefecture at 6:19:40.9. March 12,45.7 seconds after the earthquake detection at 6:18:55.2. This earthquake was practically small
11unfelt earthquake. If it was false recognition for M4.1 earthquake of Nagano prefecture ataround 6:19, this earthquake was almost unfelt in Kanagawa prefecture and it is clear
misinformation.
Although Tokaido Shinkansen train was stopped at that time, it seems to be caused by EEW by
JMA because it is hard to concern that the earthquake warning system for Shinkansen train
worked with such an earthquake. A video file is opened on YouTube. This video recorded thesituation of emergency stop by this earthquake after leaving Shin-Yokohama station at the seat
8A of ninth car, super express Nozomi #1 for Hakata station. It is impressive to understand thesituation of EEW by JMA transmitting with mobile phones and Shinkansen system.
Nozomi #1 had started smoothly and after the seat number 8A of ninth car passing the platformof the Shin-Yokohama station, the train was shaken. Room lights were turned off by powerinterruption just after it, and a mobile phone begin to ring a characteristics buzzer to inform
EEW by JMA at the same time. Then four seconds after, other mobile phones started ringing
simultaneously. The first shaking is estimated as a vibration passing a crossing and the locationof the train can be specified. On the video, the location starting ringing the EEW by JMA wasaround 400m after departing the Shinkansen train, and then the train stopped after 24.5 second.
A sound informing EEW by JMA is common for each mobile phone carrier and it is impossible
to grasp the gap between the carriers. However, because the first sound came from only one
mobile phone and secondary sound came from several mobile phones, the carrier of thesecondary mobile phones may be NTT DoCoMo having the top shear in Japan at that time.
Considering the situation at the time of the 3.11 Earthquake occurrence mentioned above
together, it seems to take 5-10 seconds to inform EEW by JMA for each mobile phone. In thiscase, because the first report of EEW by JMA for public and that for profession might issue
simultaneously, the transmission time of EEW by JMA for the power stations of Shinkansen
train can be also estimated about five seconds, same as the first informed time for the mobile
phones.
Because JMA reports that EEW by JMA requires 5.4 seconds in average from earthquake
detection to warning issuance and adding 5-10 seconds as the transmission time, the time toreceive EEW by JMA via mobile phone network is estimated about 10-15 seconds. Assuming 4km/s as the propagation velocity of the main motion, the detected earthquake motion reaches
40-60 km. In case that the depth is 10-20 km, even if a seismometer of JMA can detect the12earthquake just at the epicenter, it is impossible to inform the warning within the circle of theepicentral distance 50-60 km in advance for the large motion. At the time of the 3.11
Earthquake, JR East Company operating Shinkansen train in Tohoku area did not stop
Shinkansen trains with EEW by JMA and modified to stop in this time.
(3) Experience at the facility of EEW by JMA for advanced users and preventing people fromheading home during the 3.11 Earthquake
A meeting on the investigation of the 2011 New Zealand Earthquake was held in the day
afternoon of the 3.11 Earthquake at Institute of Industrial Science, the University of Tokyo.
When a lecturer started speaking, announcement in the campus informed EEW by JMA as“Earthquake early warning. Earthquake motion will arrive in 40 seconds. Predicted seismic
4 of Figure 1 and the time was added several
intensity is 3.”. It seems corresponding to the ○seconds as transmission time to the time 14:47:45. The announcement has no sense of urgency
at all and the lecturer waited the start shaking with many audiences to terminate the earthquake
because of EEW by JMA. The earthquake motion was clearly started when the announce said“the earthquake motion will arrive in 20 seconds.”. One parson stood up under too long shaking
with a feeling of anxiety and abnormal little by little against slowly growing earthquake motion,and it was triggered for a lot of people to stand up simultaneously and come out from the hall.
The earthquake motion continued for several minutes. I was thrown into confusion because I
felt serious matter had happened due to my assumption that the earthquake remain shaking forone minutes at the longest in Japan.
Eventually, the seismic intensity was around 5-, differently from the forecast that the predicted
intensity is 3 or it is 40 seconds to start shaking. The forecast is too much to make the people
believe that the earthquake is nothing much and I remain strong impression that the forecast is a
unnecessary information to the earthquake warning. I realized for the first time the risk ofNormalcy bias.
In addition, I experienced the preventing people from heading home. Because my mobile phonebecame no longer available since it was marginally enable just after the occurrence, I stood inline to call with public phone and made necessary contact. At that time, I noticed that the public
phones often could not accept coins near convenience stores, and then I have carried telephonecards. I walked around focusing the railway station without operation to find a way back to myoffice or home. It was impressive to see the situation changing or collapsing of a normal life as
the situation of convenience stores disappearing items, the situation of road jamming with cars,
13the situation of sidewalk filled by peoples walking or waiting a bus, the situation of loaded
buses impossible to enter and so on. Especially, the situation was rapidly worsened after 17
o'clock the closing of many offices. Because it became dark and cold and I could not doanything, I came back to Institute of Industrial Science around 19 o’clock. I was really touchedby tender-heartedness of the staffs of the office and laboratories. Here, I would like to express
my deep gratitude.
In the Tokyo metropolitan area, however the duration time of this earthquake was long, theearthquake motion was about seismic intensity 5+ and predicted to cause only little or be very
limited damage for railway facilities. Nevertheless, this earthquake caused great confusion evenfor this area. The confusion was spurred by the fact that JR, Japan Railways Company,
abandoned the operation at an early stage and kept out the passenger from the most of thestations. It is expected to ensure an accurate response to the problems to have to be improved or
to run into with validation of this situation including the behaviors of JR staffs before and after
the earthquake what and why this situation was caused. Other transportations without JR had
muddled through misery as the first situation with efforts to recovery the operation. I would
appreciate it if transportations have made an effort to identify and solve the problems to reduce
as much as possible the confusion, amid fears of the occurrence of huge earthquakes in the
future. It is most important for restarting the operation to confirm safe conditions and it isnecessary to grasp promptly the situation after the earthquake occurrence. And it is also
important to assess correctly and promptly the present condition with learning of relative
weaknesses on a regular basis and visit accessible weaknesses with changing thecorrespondence flexibly. In the future, it is expected to establish more proper countermeasures
after earthquake disaster not only to response promptly the earthquake without damage, but also
to consider the case suffering damage for facilities.
(4) Earthquake alarm system for Tohoku Shinkansen and its working condition
1) Summary
Earthquake alarm system for Tohoku Shinkansen has been replaced to the similar systemdeveloped for EEW by JMA, after the derailment of the Shinkansen train caused by the Mid
Niigata prefecture Earthquake in 2004. The new system started operation from the time of theNoto Hanto-Oki Earthquake in 2007. Although this new early warning system could not work
and issued no alarm at the time of the 3.11 Earthquake, there is almost nothing to explain thissituation properly. Therefore many people misunderstood that the new system worked as
expected and then Shinkansen trains were stopped safety. In fact, the early warning system
14renewed after the Mid Niigata prefecture Earthquake in 2004 could not fulfill a function and thetiming of alarm issuance was significantly delayed, even if compared with the previous systeminstalled at the time of starting operation of Tohoku Shinkansen nearly 30 years ago. Here, theproblems of the earthquake disaster countermeasures with renewed early warning system will beclarified.
2) Earthquake alarm system for Tohoku Shinkansen line
Concurrently with the inauguration of Tohoku Shinkansen line, the alarm system against thelarge earthquake motion started operation to detect it quickly the earthquake under the seabedaway from the Pacific Ocean coastline, with installing the alarm seismometers 80-100 km apartalong the coast line (see Figure 7). This system aimed to keep safety of the running trains withemergency brake before the large earthquake motion arriving. Specifically, in case of detecting
the earthquake motion over 40 Gal, it designed to issue alarm for the specified area considering
occurrence of the largest earthquake in the detected area. Then Compact UrEDAS had installedfrom 1997 and started function of P wave alarm in September 1998. Compact UrEDAS was set
to issue alarm after one second for the system along Shinkansen line or after three seconds forthat along the coast line. After stating operation of Compact UrEDAS, the ordinary acceleration
alarm seismometer was saved as a backup system and the trigger level was set as 40 Gal or120
Gal (in 5Hz PGA) for the system along Shinkansen line or for that along the coast line,
respectively. At the time of the 2004 Niigataken Chuetsu Earthquake, Joetsu Shinkansen line
operated Compact UrEDAS which had been developed based on the experience during theGreat Hanshin Awaji Disaster Earthquake and had the world's fastest earthquake alarm. And
Hachinohe
Morioka
MiyakoRikuzenTakada
Oshika-Hanto
Souma

KoyamaIwaki

Ueno
MiuraHanto

LegendShinkansen line
Observation station
Control Area for eachobservation station

ChoushiFigure 7 Front Detection/Alarm System for Tohoku Shinkansen: Eight Detection Sites andControl Area for earthquake (1985)

15

this system issued the alarm one second after the P wave detection as expected and interrupted
the substation against the earthquake occurred just below the Joetsu Shinkansen line. As a result
the power supply to the Shinkansen trains was stopped and the running train applied theemergency brake automatically. It was only about three seconds before the large motion. But
totally 154 passengers and crew of the train were kept safely without any injuries due to therapid brake actuation although the train was finally derailed. In other word, Compact UrEDAS
succeeded to keep the safety of the train with issuing the alarm, as expected, just before thelarge motion characterized as the near-field earthquake (see the papers on the web,
http://www.sdr.co.jp/paper.html). This Compact UrEDAS is still the fastest earthquake alarmsystem in the world, without the other products of System and Data Research.
3) Early warning system by JMA and its operation result for JR
In those days, completion of the early warning system by JMA was bruited and JR groupdecided totally adopt the system. Because JMA system required an alarm processing time fortwo seconds in the shortest or 5.4 seconds in average, the alarm was expected to be later morethan one second for the system along Shinkansen line or 4-5 seconds in average for that along
the coast line than Compact UrEDAS. Therefore, JR planed to shorten the earthquake detection
time with changing the distance of each seismometer 10 km instead of 20 km in past. Howeverthat effect was only one second in maximum, the whole time had to be absolutely later thanusual. Because the alarm processing time of the usual Compact UrEDAS for the coast line was
set three seconds, if the system was replaced to the JMA system that requires two seconds inminimum or 5.4 seconds in average for alarm processing time, whole alarm issuing time would
be one second in the shortest on the performance but be later 2.4 seconds in advance average.
Although I have pointed out to the press about the misunderstanding of reports that the
replacement aims to shorten the alarm processing time, no press covered the fact pointed out.
The early warning system with JMA method has started operation for Shinkansen line fromaround the time of the 2007 Noto Hanto-Oki earthquake, and then when the system works, SDR
has reported the working condition of the system based on the news reports and so on (see thereports on the web, http://www.sdr.co.jp/paper.html). The validation shows that the timing of
issuing alarm becomes later as expected.
And at least as of July 2011, I have fretted about issuing proper alarm for the appropriate area
eliminating the excessive alarm as possible. However after replacement, a little before the 2007
Noto Hanto-Oki earthquake, the alarm range has always extend to entire Shinkansen line. I was
surprised that the policy of issuing alarm has been changed to an easy way that may cause
16unnecessary confusion. This earthquake occurred under these circumstances. The working
situation provided below is modified and organized with my own knowledge based on the press
release or the information that has been published before now.
4) Status of Tohoku Shinkansen trains at the time of the 3.11 Earthquake
First, JR East Company says that 27 trains of Tohoku Shinkansen line were in commercial
service and 8 trains of them were stopped at a station. These stopping trains may include trainsdecreasing the speed toward to a station or leaving a station. Figure 8 shows the distribution of
the stopping trains based on the time table and the location of the running trains with the speed
estimated by news and JR reports. In addition to these commercial, a 10-car train on a test run
inspection finished in Sendai rolling stock depot run toward to the Sendai station at low speed
and the first car of this train stopped 900m away from Sendai station with derailing two axels of
the front truck of the fourth car see picture 1). Railway accident investigation report of Japan
Transport Safety Board says “The driver of the train, entering to the premises of Sendai Station
at about 72 km/h, felt the strong shake and, at the same time, noticed that the stop signal of thecab signal device turned on,” and it means the alarm arrived at the same time for receiving thelarge motion. The other trains including high-speed running trains around between Sendai to
Fukushima stopped safely without derailment because of the emergency brake before the large
earthquake motion.
5) Operating status of the early earthquake warning system for Tohoku Shinkansen
Figure 9 shows the distribution of the seismic observation stations of JMA and JR including thestation which detected the earthquake first. This figure indicates the area centered on the Sendai
and the observation value of the major stations. See Figure 1 for the situation of the earthquake
motion expression.
According to news reports, the operation status of the alarm system is organized as follows.
One of the coast line station, Kinkazan observation station installed in Oshika Peninsula
detected strong acceleration over 120Gal (5HzPGA) and issued the earthquake alarm at
14:47:03. This alarm was transmitted to the substations such as Furukawa substation withtransmission time of two seconds and stopped power supply for Shinkansen trains. The
emergency break of Shinkansen trains was activated automatically one second after this powerinterruption detection.
According to the strong motion data of K-NET, the Shinkansen train Yamabiko #61 was
high-speed running in a tunnel at 265km/h around 15km north of Sendai station and started
17

activating the emergency break almost at the same time when the seismograph of K-NET
Furukawa observatory MYG006 detected 40 Gal (5HzPGA).

Shin-Aomori① Hayate#30(310): ?
km/h, RokunoheTunnel,
614.9km
Hachinohe②Hayate#25(about 500):
245km/h, Tunnel, 578.6km③Komachi#25:? km/h④Komachi#30:
Morioka? km/h⑤ Yamabiko#59(98): 270km/h,⑥Hayate#28(780): ? km/h,
4th Kitakamigawa Bridge
Viaduct, 488.5km
474.7km⑦Yamabiko#60(?):
stopping at Ichinoseki st.
⑧ Hayate#27(764): 270km/h,
Sanbongi Tunnel, 356.4km⑨Yamabiko#61(397): 265km/h,
4th Rifu Tunnel, 340.5km
Sendai⑩Max Yamabiko#144(?): ? km/h,
Hirosegawa Bridge, 321.7km⑪Tsubasa#188:
stopping at Yamagata st.
⑫Tsubasa#137: ? km/h
⑬Tsubasa#144: ? km/h
⑭Max Yamabiko#139(?):
stopping at Fukushima st.
Nasuno#274(?):

23 Yamabiko#56: ? km/h

Epicenter

Fukushima⑮Yamabiko#58(?): stopping at Fukushima st.
⑯ Hayate#26(1083): 270km/h, Fukushima Tunnel,
stopping at Kooriyama st. before service
246.4km⑰Yamabiko#63(220): 270km/h, IIzawa Tunnel, 181.4km↑⑱Max Yamabiko#142: 238km/h⑲Nasuno#259: ? km/h
Stopping location,
Kilometrage from Tokyo( ): number of passengers
Utsunomiya⑳Yamabiko#216:stopping at Utsunomiya st.
21 Hayate#29: 270km/h
22 Max Yamabiko#141: ? km/h

24 Yamabiko#211: Ohmiya
stopping at Ohmiya s
25 Hayate#24: ? km/ht.
Ueno
26 Yamabiko#65:
27 Max Yamabiko#140: stopping at Ueno st.
stopping at Ueno st.

0

50

100

200km
2015-04-16 revised

Figure 8 Stopping Locations of 27 Operating Trains relating Tohoku Shinkansen at
the time of the 311 Earthquake
18

JR_Kurikoma-Kogen station K-NET_Utatsu_MYG002

K-NET_Tsukidate_MYG004
RImax=6.6？
5HzPGA=1812Gal？

JR_Furukawa sub-station
On-Site staion

K-NET_Shidugawa_MYGH12
K-NET_Kitakami_MYG008

Yamabiko#61:265km/h, Tunnel at 15km? north of
Sendai st.
Test train: low speed, Two axles offront bogie of fourth vehicle were
derailed, 900m from Sendai st.

JR_Sendai station

nsen

Hayate#27:270km/h, Tunnel at 10km? south of
Furukawa st.

JR_Furukawa station

Touhoku Shinka

K-NET_Furukawa_MYG006
RImax=6.2
5HzPGA=506Gal

JMA_Oouri EEW station
RImax=5.2, 5HzPGA=442Gal
K-NET_Ishinomaki_MYG010
RImax=5.9
5HzPGA=428Gal

K-NET_Sendai_MYG013
RImax=6.2, 5HzPGA=1068Gal

MaxYamabiko#144:?km/h, Hirose Bridge

K-NET_Kitakami_MYG008
RImax=5.5
5HzPGA=301Gal
JR_Kinkazan
EEW Front station

K-NET_Oshika_MYG011
RImax=5.5
5HzPGA=476Gal

JR_Sendai sub-station
On-Site station
Sendai Air-Port

Figure 9 Situation of around Sendai at the time of the 311 Earthquake: Arrows indicates the
direction and the location of stopping trains, orange circles are K-NET and KiK-net sites,
green circles are detection sites for Shinkansen, and blue one is JMA observation site.

Figure 1 shows the time 14:47:03 <37> when Kinkazan station issued the alarm with exceeding
120Gal (5HzPGA). It was a moment when the first peak of the earthquake arrived at Oshika
peninsula and was quite late as a time to issue the alarm. It was only 3-4 seconds after issuing
alarm at Kinkazan station to exceed 40 Gal (5HzPGA) at the K-NET station close to the
Shinkansen line, K-NET Sendai station MYG013 and K-NET Furukawa station MYG006 at
14:47:06 <40> and 14:47:07 <41>, respectively. On the other hand, if K-NET Oshika station
MYG011 instead of Kinkazan JR observatory issued alarm over 40 Gal as same as at the time ofthe start operation of Tohoku Shinkansen line, the alarm would be issued at 14:46:59 <33> andprecede the current alarm by about four seconds. And assuming that Compact UrEDAS works
as same as at the time of the Niigata-ken Chuetsu Earthquake, the P wave alarm may be issued
at 14:46:48 <22>, advanced about 15 seconds for the current alarm. However even the latealarm fortunately caused no serious damage as derailment of the train in service at the time of
the 3.11 Earthquake, the difference about 15 seconds has unimaginable meanings under theextreme situation such as at the time of the Niigata-ken Chuetsu Earthquake.
It is major problem that the earthquake early warning system with JMA method did not function
19

at all. JMA method originally cannot gain the time margin for the damaged area caused by theM7 class earthquake concerned a frequent occurrence in near future. If EEW by JMA cannot
function against over M8 class earthquake it has no value. It means that the current Shinkansen
lines depend on only the initial 40 Gal alarm against the damage earthquake occurring neat thelines.

Time in seconds from2010/3/4,00:18:52.14

台湾・甲仙地震（M6.4, h22.64km）
40の警報シミュレーション

35

Maximum Motion

台湾・甲仙地震 M6.4, h22.64km

25

4.8 5.0
4.3 3.8
5.3

15

5
4
40Gal ↱
10Gal ↗
5HzPGA

10
5

4
RI = 2

5.4
5.1
5.9 5.6

3.9

4.8
5.5 4.5

20

in Gal

5.1

5.0

30

５HzPGA

1.5

5.0

140Gal Alarmat ISCER10

10Gal

P-wave arrival
FREQL Alarmat ISCER10

3

Fastest FREQL Alarm

0
0

50

100

Epicentral Distance in km

Realtime Intensity RI

Figure 10 FREQL Simulations for the 2010 Kaohsiung Earthquake M6.4 on
2010/03/04 in Taiwan6) 40Gal alarm system for Taiwan Shinkansen
Although Taiwan Shinkansen operate modified 700 series Shinkansen train developed by JR
Central company with a maximum speed of 300 km/h, it has equipped only 40 Gal triggeringsystem as the earthquake alarm system. Under this situation, M6.4 earthquake occurred 50km
away from the Shinkansen line on March 4, 2010 and this earthquake caused the derailment of
one axle of the first car running in high-speed. Although a wayside alarm seismometer was
issued a 40Gal alarm for this earthquake, it is estimated that there was very little time margin
before the derailment. Figure 10 shows the time from issuing the alarm to starting the large
motion based on the simulation using the strong motion record provided Taiwan weather bureau.
If FREQL was installed as a wayside on-site P wave alarm system, it could earn more sevenseconds for time margin than the current system and avoid the derailment. Furthermore, if thefront detection P-wave alarm system to capture the earthquake closer to the source region, it
20

could earn additionally about eight seconds for time margin and it is expected to improve
substantially the safety of the running trains. Additionally, the wave propagation situation using
the realtime intensity at the time of this earthquake can be seen in the video file
(http://www.sdr.co.jp/activities.html#311tohoku). It seems that the large intensity observed
concentrating around the place of the derailment.
7) Earthquake damage for the Tohoku Shinkansen line
Structures of the Tohoku Shinkansen line locates more than 200km apart from the beginning of
the destruction starting point of the 3.11 Earthquake. They are also over 100km from theboundary of the source region of about 500km × 200km lying along the Pacific Ocean coast. At
an area away from the fault, it is estimated that the earthquake motion lost the sharpness anddestructive power. The recorded strong motion shows clearly different behavior from that of thenear source earthquake with large shape motion. Nevertheless, structures of Tohoku Shinkansenline suffered severe damage as shown in Figure11 from the JR East report. The damage extent
for the Shinkansen facilities are relative larger than that for the neighborhood facilities and it isnecessary to take a proper counter measurements with clarifying the cause. Tilt and breakage of
the wire pole hanging the overhead wire are big problems for the safety of the Shinkansen train
running high-speed. Figure 12 shows the tilt and breakage of the wire pole between Sendai and

Figure 11 Damage of Tohoku Shinkansen facilities against the 311 Earthquake(source: website of JR East)
21

Figure 12 An example of Damage of wire poles for Shinkansen at the time of
the 311Earthquake

Iwakiri as an example. The 1993 Hokkaido Nansei-Oki Earthquake on July caused the tilt or
breakage of the wire poles of the Tsugaru Kaikyo line as same as this time. The viaducts ofTsugaru Kaikyo line was built with a specification for Shinkansen line and the wire poles werealso set in the same way as the Tohoku Shinkansen structures. I am wondering the validity ofthe building way since the beginning because of its particularity. I proposed to improve theearthquake resistance with increasing the rigidity by connecting the top of the wire pole
opposing inbound and outbound lines a wire pole with because exceptionally high predominantfrequency of around 3 Hz was not affected in case of Tsugaru Kaikyo line (Nakamura et al.,1993). There were some wire poles with connection the top at damaged area and each of them
did not affected. Severe tilt or breakage of the wire poles were occurred at 5km to 7.5km
northeast from Sendai station, between Sendai station and Sendai rolling stock depot. Not only a22

10-car train on a test run but also trains in commercial service as Yamabiko #61 and Hayate #27
passed this section just before the 3.11 Earthquake, and it could be catastrophic if the earthquake
had occurred just a few minutes before. The tilt or breakage of the wire pole is a problem to besolved only by hardware response of the facility.

6. Tsunami Warning(1) Tsunami hazards
I was shocked into silence from the extremely huge damage by tsunami caused by the 3.11
Earthquake. The image of tsunami hazard in Japan in my mind considering the earthquake
disaster mitigation is quite outstripping from the reality. I think that the problem is not available
to image properly the tsunami hazard, caused the hazard for the nuclear plant, beforehand,because it seemed to be possible to take some counter measures if many relations for disastermitigation could image properly the possible hazard. I feel in need to establish effective
countermeasures against the tsunami hazards with not only recognizing and investigating thehazards in detail but also constructing the proper image of the tsunami hazards, in order toreconstruction from the tsunami hazard in practice or to make provision to evacuate or survive
from the tsunami hazard.
(2) My surprise and question
There was a number of surprising matters for me on the scene of tsunami attacking.
* Why did houses sweep away easily? And a video shows a few independent wooden houses
still remaining among the houses swept. What is the reason? Are there hints to keep remaining?
* Although I remember there had been many ships escaping from the port in past, TV programson NHK and other stations reported the situation after tsunami warning for the 3.11 Earthquake
and there was a few ships to escape. What is the difference?
* At the time of the 1983 Nihon-kai-Chubu Earthquake, tsunami killed more than 100 people inthe coast. It was said that such an accident never happens in the Pacific Ocean side because thepeople have a custom to evacuate to higher place when large earthquake occurred under the sea
spontaneously. Did the custom diminish drastically today only 28 years after that?
* I heard after the 3.11 Earthquake that there is a legend that tsunami attacks twice people in
Sanriku area during their life. Is this legend well-known among that area still now, especially for23young generations?
Matsushima is a famous s picturesque place with many small islands in the bay. It is said that
there was relative small tsunami damage in this area because these islands diminished theenergy of tsunami. And an inland sea Mangoku-ura area located east of Ishinomaki seemed tobe suffered less tsunami damage.
These facts suggest that an idea diminishing the energy effectively could be one view. The idea
is to withstand the tsunami even if the tsunami is higher than estimated and is not an idea toequip the huge rigid seawall keeping out the tsunami perfectly. The destruction of the seawall
may cause unexpected hazard if the seawall only resist immoderately against the power of thetsunami as same as the earthquake. I think that it is required an idea that the facility must be
destroyed during under control.
I am painfully aware of the idea from the earthquake damage situation of the 1995
Hyogoken-Nambu Earthquake, and I also have a strong desire as same from the tsunami hazard.
How can we control against the tsunami hazard? I think that the mega-float may be a hint for the
new idea against the tsunami hazard.
Was there no lesson except the evacuation to higher place from Meiji or Showa Sanriku tsunami
hazard? Although the importance of the evacuation to higher places is obvious, the fact that theother countermeasure for the person who failed to escape is only the evacuation tower seems
poor idea. It is better to keep various countermeasures for people under various situations. It
may be required a simple plan corresponding to various situation as emergency without enoughtime or as for old people or handicapped people, for example.
(3) Problems of tsunami warning by JMA and the necessity of JMA reformation
The accuracy of estimated height or the manner of issuing the tsunami alarm by JMA at the timeof this tsunami hazard became a problem and an expert committee to solve the problems was set
up. However, is this problem setting appropriate? Tsunami warning by JMA was issued very
quickly at 14:49 for the 3.11 Earthquake and it had more than 30 minutes before attacked by thelarge tsunami. Although the tsunami prediction as more than 3m or 6m depending on thelocation was underestimation in retrospect, it might make recognize to be attacked byabnormally large tsunami than usual. Therefore, the problem of this tsunami warning is not theaccuracy or the manner to issue warning information. Problem of the tsunami warning by JMA
24

lies in the system itself shifted as top-down warning without proper debate after the Great
Hanshin-Awaji Earthquake. Of course the tsunami warning is not without a problem on its
accuracy or the manner to issue. Because the expression of the warning was easy to bring into
the normalcy bias, it can not deny the possibility to provide various excuses not to evacuate
immediately, such as that the seawalls is higher than the height of the predicted tsunami or it issafe to go up to the roof in case of failure of evacuation. Additionally, it can be pointed as aproblem on the news reports that the impression of repeated information of the first tsunami
height was 50cm at the predicted time had stayed and it made a similar situation for the otherlow tsunami warning for the earthquake few days before.
However, a bigger problem is that the wisdom carried on the tradition of suffering the tsunami
hazard in the area may be lost in these 20-30 years for any reason. During this time, the tsunami
disaster has come to be treated as a natural disaster to be addressed by the nation absolutely.
While the government says that the basic of the response against the natural hazards is self-help
efforts, the central government constructs huge seawalls or makes dependency on the central
government with unifying the tsunami warning for JMA. This kind of the measure by the central
government makes the local government lost the tension for the natural hazard. This trend has
gradually lost the basic stance of local society to handle the problem by itself, such as theextinction of a local tradition, wisdom or customs for various aspects against the tsunami hazard.
This period overlaps with the period that the tsunami warning is no longer stated only to beissued by JMA with the amendments of the law.
Like Dr. Katada, Professor of Gunma University, there are examples to save not only
schoolchildren but also many local residents with a practical teaching of the strategy against thetsunami. This is a typical case of the self-help efforts. There are academic research institutions,
local government agencies, industries and livelihoods with the characteristics of each region.
May local residents lose sight of the importance of devisal against various natural hazards withcooperation to develop the local industry for the region?
Of course there are facts to be addressed in national scale. The basic part of the accurate
earthquake observation requires a nation scale construction. Even in such a case, it is possible totransfer the information to each region in realtime and local organizations can utilize thisinformation for the local disaster prevention with processing using of the regional properties. It
is expected that each regions create good countermeasure competing against each other.
I feel that local residents or organizations slowly lose their mettle to deal by themselves against25

the earthquake or the tsunami as a target of the alarm, if they relinquish the rights to issue alarmfor the institution of authorization as JMA, in case of the society having a tendency to blindly
submit to superiors as Japan. For this reason, it seems that the custom and knowledge to behanded down to future generations in the area becomes a dead letter gradually. It resulted in amarked technological stagnation of JMA like a king of the hill, and there is always a risk getting
in a situation such as one lap behind, far from the cutting-edge technology. Now is the time torequire JMA to provide the promptness and accuracy of the earthquake observation, and tochange the framework that the provided information can be preceded mainly by the region itself
and added the characteristics or necessity by each regional organization.
It is necessary for realization of this consideration to change drastically the Meteorological
Service Act. Moreover, the organization as JMA or NIED, National Research Institute for Earth
Science and Disaster, assuming a important role for the disaster prevention with engineering
sense has a few staffs educated as engineer. This current situation must need to be corrected assoon as possible. It seems to become a time to discuss completely the future of the government
for meteorological and terrestrial phenomena and reform the framework itself. This reformationmust aim to establish the policies for the disaster prevention free from the past back ground or
constraints. It is necessary to establish the framework for the next generation assigning thereally needed manpower for the required department, without keeping or saving the old humanresource allocation for the human-intensive observation.
Earthquake or tsunami hazard causes drastic damage for a particular area. Disaster relief andrestoration support for such serious damaged area is exactly the work for the country. It isnecessary to identify the location of the witheringly damaged area and to send the restoration
support team with needed materials or staffs in national scale. Administrative agencies
providing the information to enforce the support promptly and effectively are the nationalorganizations as JMA, NIED, Public Works Research Institute, Building Research Institute orPort and Airport Research Institute. Of these, JMA seems to be a backward organization andneeded significant revision. For example, JMA restricts to provide the precise earthquake
parameters for the other organizations. In case of the earthquake occurring in the inland areas,even not large earthquake sometimes causes a catastrophic damage in the epicentral area.
Although the precise earthquake parameters are the critical data to identify exactly the damaged
area, the system to provide the precise earthquake parameters form JMA is not established anddoes not put any efforts into establish. There are many problems but currently the accuracy ofthe preliminary information from JMA is only about 10km.

26

7. Afterword
Here I mentioned about the interest matters from the viewpoint of the earthquake disasterprevention with a focus on the 3.11 Earthquake. It will be a real pleasure for me that this report
touches up various discussions.

Note: This report is an English version of SDR Report No.5 issued on 2011/07/11 withcorrection and adding new data.

27