2009/04/22

Earthquake Early Warning andRealtime Disaster Prevention

Yutaka NAKAMURA, Dr. Eng.
System and Data Research, Co., Ltd.
Visiting Professor, Tokyo Institute of Technology

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

Videos Recorded at the Moment of Earthquake Attack

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

EEW andEarthquake Disaster Mitigation

2009/04/22¾The Basic Countermeasure isStrengthening the Facilities¾EEW is only a Trigger for
Quick Response against Quake¾It is important for EEW to avoid
Overestimation¾Late EEW is Unnecessary¾Accurate Information is
Extremely Important for
Quick Response after Quake
Damage of the 2009 L’Aquila Earthquake (Mw 6.3)
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

Concept of Earthquake Early Warning
On-SiteDetection/Alarm
Front
Detection/AlarmP
P-wave Alarm

S

S-wave Alarm

Fault Rupture

There are two kinds of theearthquake alarm. One is“On-site Alarm” which is thealarm based on theobservation at the side of
the objects to be warned.
The other is “Front Alarm”
which is the alarm based on
the observation near theepicentral area to warn forthe possible damaged area.
For each, there are more
two kinds of alarm. One isso-called “S-wave Alarm” or“Triggered Alarm”. And theother is “P-wave Alarm”.

We have developed a prototype system for EEW as UrEDAS in early 1980’s.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

Introduction of UrEDAS
UrEDAS, Urgent Earthquake Detection and Alarm System,
is the first real time P-wave alarm system over the world inpractical use in 1992 for Tokaido Shinkansen.
It is characterized to be able to process digitized waveformstep by step without storing waveform.
Amount of procedure is not differ from each other either
earthquake occurs or not, so it expected not to be occurred
the system down due to the over load.
UrEDAS is able to use not only for the On-site alarm but
also for the Front alarm.
5System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

Functions of the UrEDAS
There are two types of UrEDAS; “UrEDAS” and “Compact
UrEDAS”.
Function of the UrEDAS (1985) is to estimate the magnitude
and the location of detected earthquake in three seconds
after initial P-wave detection and issuing the alarm for
expected damage area.
On the other hand, Compact UrEDAS (1998) can evaluate
whether the earthquake will be destructive or not using
Destructive Intensity DI and issues alarm one second afterP-wave detection if needed.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

The UrEDAS Technique for
Estimation Methods ofLocation, Depth and Magnitude
using a Single Station Datain Realtime
The development of UrEDAS had been almost completed in themiddle of 1980’s. UrEDAS realized realtime independent process.
Although the JMA system intermittingly processes with several
seconds, UrEDAS processes in every sampling time. Warning timeof UrEDAS can set arbitrary. At first the warning time set to threeseconds, but we have found the time is able to set one second
without problems at least for M7 class earthquake. For New
generation of UrEDAS, FREQL, the warning time is set to one
second. I would like to show the potentiality of them instead of
explanation the UrEDAS techniques in detail.
7System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

UrEDAS is only true
realtime system
UrEDAS can estimate
Epicentral Azimuth,
P-wave Incident Angle andetc. in realtime
I would like to show thepotentiality of UrEDAS;
Rupture Trace for RealEvent in realtime
using one UrEDAS station
8System and Data Research Co., Ltd.
Tokyo Institute of Technology

UrEDAS Application to Rupture2009/04/22
Process Estimation in Realtime
Pasadena

M<3 M <4

M<5

In case of the 1994 Northridge Eq.
(after Nakamura 2001)

M<6Ur gent

Ear t hquake Det ect i on & Al ar m Syst em

Pasadena

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

This is an example ofrupture process
tracing in realtime
using the data ofPasadena UrEDASstation. The plane
between backazimuth and incident
angle is correspondto left upper crosssection. Rupture canbe seen to go tosurface fromhypocenter.

2009/04/22

Estimation Destructivity andWarning Methods ofCompact UrEDAS

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

Captured Photos at the time of the 1995 Kobe Earthquake

P wave arrival

emiT

Principal motion arrival

Motivation of Compact UrEDAS development is the Kobe Earthquake. On theVTR, they noticed the initial P wave motion as something happen, and then thesevere motion attacked them after a few seconds. Although there was only afew seconds between something happen and recognition of earthquake, it wasanxiousness and fearful because they could not understand what happened
and felt relieved after recognition of the earthquake occurrence. As the counterof this kind of feeling, the earlier earthquake alarm is required and I developed
the Compact UrEDAS to make the alarm within one second after P wave arrival.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

The P wave alarm of Compact UrEDAS demonstrates
the effectiveness as making the derailment not catastrophe0123456

P-wave Arrival78

2009/04/22

9 1 0 11 1 2 1 3
P-wave Alarm

S-wave Arrival

Main Derailments

5 seconds

Principal Motion

Time

②:
Successive Vehicle
You can see derailment situation
andsituation between body
Example of andcontact
railroad,
Compact
UrEDAS
Warning

Derailment
Location

Final Derailment
Final Situation
Situation

normal vehicle
derailment vehicle byflange climbing
large relative displacement
railway deformation

12(a)先頭車
Front⑩ExitTunnel

System and Data Research Co., Ltd.
Tokyo Institute of Technology

Rear ①(b)最後尾車2009/04/22

Ultimate Earthquake Early Warning System
FREQL series and AcCo - PS

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

FREQL(Fast Response Equipment against Quake Load)
FREQL is developed for the earthquake
warning system based on theexperiences of development andoperation of the world first P wave alarmsystem UrEDAS.
FREQL function is combined thefunctions of UrEDAS, Compact UrEDASand AcCo.
P wave alarm is available 0.2 seconds
in minimum after P wave detection ( thefastest time will be 0.1 seconds in 2009)
S wave alarm is also available. (basedon acceleration and real-time seismic
intensity RI.)

14System and Data Research Co., Ltd.
Tokyo Institute of Technology2009/04/22

Processing 警報処理時間
Time for P-wavein sec.
）
（秒Alarm

Change of processing time for EEW
10cf. Equipment developed by JMA

SDR products

53UrEDAS
Test observation

UrEDAS 3 sec.

Average 5.4 sec.

JR Tokaido Shinkansen
Tsunami warning system Minimum 2.0 sec.
for Wakayama PrefectureThis figure shows thechange of theprocessing time forEEW.

While JMA system
performs every one
1Compact UrEDAS 1 sec.
Tohoku Shinkansen
second for the alarmTokyo Metro
0.5
processingMin.
intermittently withFREQL Minimum 0.2 sec.
0.1
0.2
stored data, UrEDAS
Tokyo Metro, Odakyu
sec.
Fire Departments of Tokyo, Osaka and so onand FREQL perform
0.1
1980
1985
1990
1995
2000
2005
2010 the procedureYearcontinuously in every
Development of Processing Time sampling time.

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

FREQL is toward to the new field, asfor the Hyper Rescue Team in the risk of aftershocks

Hyper rescue team acts in arisk of large after shocks.
After the Niigataken Chuetsu
Earthquake, the hyper rescue
team approached us to adopt
FREQL as a support system forthe rescue activity.
the 2004 Niigataken -Chuetsu Earthquake

Rescue Activity of Hyper Rescue Team

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System and Data Research Co., Ltd.
Tokyo Institute of Technology

Tokyo fire department andother departments in nation
wide have adopted the portable
FREQL as an equipment tokeep the safety against the riskof the second hazards caused
by aftershocks during theirrescue activity, not only inJapan but also in Pakistan andChina.

2009/04/22

FREQL: Portable TypeFirst model in 2005
Second model in 200717

System and Data Research Co., Ltd.
Tokyo Institute of Technology2009/04/22

Going to New Horizons

AcCo–PSfor Surviving
and Quick Response
Third Model for Various Purposes
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

Comparison between
JMA system and SDR system

2009/04/22

This video is NHK news
“UrEDAS Information Service
will start in this year” thatbroadcasted at 1993/01/18.
1993/01/18
Unfortunately, this project
could not be realize becauseof strong opposition fromJMA. Fourteen years later,
October 2007, JMA began
EEW service same as
UrEDAS Information service.
I would like to compare EEW
by JMA and EEW by oursystem
19System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

Actual Example with Simulated Resultsof FREQL or AcCo for Recent Damaged Earthquake
P-wave Alarm ( RI=1.5) by FREQL
Triggered Alarm (5HzPGA=10Gal) by AcCoBeginning of Principal Motion
Occurrence Tim e of Maxim
umMotion
Motionaximum

454035

FREQL Quicker Zone

3025xaMmu
im2008.6.14
Mjma 7.2
Depth 8km

noit
Mo

Damaged Area

20
1510500Q
ERF

1020

Alarm Alarm
by JMAJMAmral
LA

30405060708090100110

Epi-central Distance in km

20System and Data Research Co., Ltd.
Tokyo Institute of Technology

120This figure shows
comparison between
the EEW by JMA andsimulated on-site
alarm of FREQL andAcCo using strong
motion records.
You can see that
JMA alarm spread
after the strong
motion in damagedarea.

Comparison between
EEW of JMA and on-site FREQL
Time from
Earthquake Occurrence in seconds
地震発生からの経過時間（秒）
地震発生からの経過時間（秒）

45
45
4040

tionoMmu
Maxim

緊急地震速報第６報（一般への警報）
緊急地震速報第６報（一般への警報）
6th EEW of JMA (to people)

3535

2008.7.24
Mjma 6.8
Depth 120km

最大震度発現時
最大震度発現時3030主要動の始まり
主要動の始まりnniinngg
niniggeeBB

2525

ttiioonn
ooM
Mllancciippa
ooff PPrriin

EEW by JMA for publicarrived after maximum
motion

1st EEW of JMA (to customer)
緊急地震速報第１報
緊急地震速報第１報

2020
15
15

Even EEW by JMA forcustomer arrived after Onsite FREQL information

緊急地震速報地震検知
緊急地震速報地震検知
Earthquake Detection by JMA

1010

FREQL
Alarm
FREQL:
オンサイトP波警報
FREQL:P-wave
オンサイトP波警報
FREQLDetection
FREQL:
オンサイトP波検知
FREQL:P-wave
オンサイトP波検知

5500
00

20
2040
40

60
60

80
80

100
100

震央距離(km)EpicentralDistance in km
震央距離(km)21

2009/04/22

System and Data Research Co., Ltd.
Tokyo Institute of Technology

Even for a deep
earthquake EEW by JMA
can be significantly later
than On-site FREQL

Comparison between
EEW of JMA and on-site FREQL

2009/04/22

2008.9.11
Mjma 7.1
Depth 20km

Time2008年9月11日9時21分00からの経過時間（秒）from 2009/09/11, 09:21:00 (JST) in seconds

5045

FREQL/AcCoによるオンサイト警報シミュレーション結果

最大動発現時tionomMuxim
Ma
ttiioonn 主要動ooMMl
開始時
cciippaal
ninr
ir
PP
ffonniinngg oninigBBeeg

P波検知線
RI値1.5警報
RI値2.0警報
10Gal（5HzPGA）警報
主要動の始まり最大動の発現時40353025

EEW by JMA arrived inalmost same time of Swave arrival

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3th緊急地震速報第３報＝一般への速報
EEW of JMA (to people)

151050100

P波
警報時

Alarm
1st EEW of JMAev
a
緊急地震速報の第１～３報
w
Pno
Lit
Q
ce
Et
(to customer)
FRQL P De
ERFetis
OnEarthquake Detection by JMA

110

120

130

緊急地震速報の地震検知時刻

140

150

160

170

震央距離（km）
Epicentral
Distance in km

On-site FREQL
information arrived over
10s before the S-wavearrival
Even for a distantearthquake EEW by JMA
can be later than On-site
FREQL up to 10s

The EEW by JMA always arrives after strong motion in damaged area. We would like to request
to JMA to provide exact and accurate information just after the Earthquake instead of late EEW.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

What kind of information is required
for earthquake disaster mitigation?
JMA restricts providing the earthquake information by
unnecessary lows since December 2007.
But what truly important for EEW is to develop the“grass roots“ network to build awareness to keep
safety by ourselves.
Public authorities with dense observation network areexpected to provide the exact and precise earthquake
information immediately after the event.
JMA must abolish the restriction not only for theearthquake information but also for the tsunami warning.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

An Example of Issuing
Late Warning and Wrong Focal Information
Corrected Information
Wrong Information

M6.9

After the 2007 Noto-Hanto-Oki earthquake, during
over three hours, Seismic Information (Location,Depth and Magnitude) was reported with wrong
information. According to this wrong seismic
information, no damage and no tsunami wereassessed. But, unfortunately sever damage wasreported in hours later. Quick response may be casedby the late result from this wrong information.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

What is necessary for earthquake disaster prevention? 2009/04/22
Before and During Quake
After Quake
Quick Response
Using On-Site Alarm
against Sudden Quake
2.5
AcCo

Escape toSafety Zone

# Escape to Safety Zone based on
Each Feeling or On-Site Alarm,
Needless Alarm by Authorities as
JMA Because it is Too Late
# Check the Safety Zone Constantly# Image and Real Training to Escape25

M6.9noitanigamIderre quitsaesir
Dis# Quick Rescue at the Possible
Damage Area based on theExact Earthquake Information
by Authorized Organizations

System and Data Research Co., Ltd.
Tokyo Institute of Technology

Concluding Remarks

2009/04/22# According to the recent earthquakes of M7 class, the epicentral region isalmost completely damaged. For the epicentral area, the EEW by JMA
cannot be issued before the beginning of the strong motion; only the On-site
P wave alarm is valid for surviving.
# The nationwide system is not necessary to realize the On-site P wave
alarm, and it is better to utilize the “grass root” network by each facilities.
# In the complete damaged area, task forces are required from the outsideof the damaged area. Because it is very important to know exactly where
the complete damaged area is, exact information of the earthquake include
the aftershocks are required.
# Not only JMA but also the regional universities or NIED, having dense
observation network, must issue this kind of detailed information.
# JMA should not restrict issuing the information by these organizations.
# According to this information, the task force should concentrate to thecomplete damaged area for quick rescue activities in several tens minutes.
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System and Data Research Co., Ltd.
Tokyo Institute of Technology

2009/04/22

END
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System and Data Research Co., Ltd.
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