Planning for Receipt of Special
Earthquake Warning Information in
the Nankai Region: Guidance for
Municipal Governments

Interdisciplinary Research Team: Disaster
Prevention Research Institute, Kyoto University

Table of Contents

Forward………………………………………………………………………………… 3
Special Earthquake Information:
An Explanation of the System………………………………………………5

The Region…………………………………………………………………………… 5
The Scenarios………………………………………………………………………. 7
Issuing an Advisory/Warning………………………………………………. 8
Divided and Combined Plans………………………………………………. 9
Using this Guide…………………………………………………………………. 10

Planning Guidelines……………………………………………………………. 12
Appendix:
Sample Advisory/Warning Messages………………………………… 33

Forward
This document contains recommended planning actions formunicipal governments, villages, towns, cities and prefectures in the
Nankai region of Japan. The actions in this guide are specific to receipt
by municipal governments of “special earthquake warning information”(SEWI) from the Japan Meteorological Agency (JMA) indicating thatseismic activity in the Nankai Trough has raised the short-term
probability of a large potentially tsunami-genic earthquake. The
objective of this guideline is to promote planning among jurisdictions
that have not, thus far, developed plans and offer reasonableadditional planning options for jurisdictions that have plans for thiscontingency.
The planning recommendations in this guideline are based onbest practices from municipal governments in the Nankai region andother nations with similar operational earthquake forecasting systems.
These recommendations are consistent with those published by thenational government of Japan as White Papers on Disaster
Management in 2015, 2019 and 2021, but go beyond the national
government’s recommended planning actions by adding additional
considerations deemed important. This document will be distributed at
all training seminars we plan to conduct in the Nankai region over the
coming year and will incorporate new actions that emerge during theseseminars, making it a dynamic rather than static guide.
The actions described in this guideline are grouped into six
categories: evacuation, resident home preparedness, alert period
communications, coordination and cooperation, internal mobilizationand postponement of non-essential activities. In an appendix to thisguide, we have included a brief summary of the results of our survey
and interviews conducted with disaster managers in the Nankai region
which contributed to our understanding of the opportunities andconstraints faced by municipal governments that may confront the3challenges of a Nankai earthquake alert. This guide is divided into
sections that are organized around six sets of recommended planning
actions, each introduced by assumptions and justifications as to why
we consider them to be best practices in an earthquake alert andspecial considerations that emerged in our year-long study. Where therecommended actions in this guide overlap with those provided by thenational government, we have referenced the location of therecommended action in the national guidance documents.
In the sections that immediately follow, we provide some basic
background information on the earthquake forecasting system, theregion that is the focus of the alerting system, the scenarios thatwould cause an advisory or warning to be issued and how theoccurrence of one of the scenario events would be evaluated and an
alert issued. We have also included an observation from our survey
conducted between September and December 2022 that most local
jurisdictions in the Nankai region have different provisions in theirplans for response depending on whether the alert received is anadvisory or a warning while others have the same provisions for bothan advisory and a warning.

4Special Earthquake Alerts in the
Nankai Region: An Explanation of
the SystemI.

The Region

The geological area to which this guideline applies is the Nankai
Trough, which extends from Suruga Bay in the north to the Pacific
Ocean facing area of Kyushu. This portion of the subduction zone
includes three subsections, the Tokai, Tonankai and Nankai all capableof generating large magnitude earthquakes and tsunamis.
Figure 1: Tokai, Tonankai and Nankai Regions of the Nankai TroughSource: Japan Agency for marine-Earth Science and technology(https://www.jamstec.go.jp/donet/rendou/en/about/index.html

The region includes 707 municipal governments (cities, towns andvillages) located in 29 prefectures (Cabinet Office, 2015). Thesejurisdictions were defined as those that would be subject to 6- shaking
intensities on the Japan Meteorological Agency’s intensity scale (SeeFigure 2). A total of 139 jurisdictions (See Figure 3) were identified as
5being at risk of both strong earthquake ground motion and a tsunami
of 30 centimeters or more that would arrive within 30 minutes of amajor earthquake (Areas of Special Reinforcement of Nankai
Earthquake Tsunami Evacuation Measures).

Figure 2: Map of Maximum Intensity Distribution in the Nankai Region

Figure 3: Maximum Tsunami height at High Tide in Nankai Region

Source: Cabinet Office, Government of Japan 2015

The Cabinet Office in March 2018 established the Working Group on
Disaster Risk Management for Anomalous Phenomena along the6Nankai Trough (Cabinet Office, 2019). Three scenarios were identified
and described, that if they were to occur, the Japan Meteorological
Agency (JMA) would convene a council of scientists to determine
whether an alert will be sent to jurisdictions in the defined Nankai
region warning them that the probability of a major earthquake had
increased for a period of a few days.

II.

The Scenarios

The scenarios included a magnitude 8 class event, a “partial area
rupture,” deemed most likely in the eastern portion of the Nankai
Trough. The occurrence of this scenario earthquake is estimated tooccur once in 100 to 150 years and would represent a significant
probability gain, that is, a follow-on similar or larger event is 100
times more likely than the normal background seismicity rate. The
scenario is based on the two most historically recent major
earthquakes in the region including the 1944 MW 8.2 Tonankai
earthquake and the 1946 Mw8.6 Nankai event. Previous major
earthquakes (both Mw 8.6) in Tokai and Nankai occurred 32 hours
apart in 1854.
Two additional scenarios are regarded as raising the short-term
probability of a major earthquake and tsunami. The first is amagnitude 7 class event, a “limited area rupture” expected to occur inthe region with a frequency of once in 15 years and represents aprobability gain of “once in a few hundred times.” (Cabinet Office,2019, p. 56). A slow slip event as recorded on strainmeters may, after
qualitative assessment and if regarded as anomalous, constitute thethird scenario that could trigger an alert by the JMA to local
jurisdictions in the region. Such events occurred in the days prior to
the March 11, 2011 Great East Japan Earthquake and Tsunami.
The three scenarios represent two levels of assumed risk. The
magnitude 8 scenario would be a major damaging event whether or
not a follow on “twin earthquake” were to occur and in addition to7

triggering a major response effort, it would prompt a “major
earthquake warning” for adjacent regions within the Nankai Trough.
Magnitude 7 class earthquakes (“limited area rupture”) or slow slip
events are expected to occur more frequently and, in the case of theearthquake, cause far less damage. These scenario events would be
evaluated by the JMA and, if deemed precursory to a much larger
earthquake, an earthquake advisory would be announced.

III. Issuing an Advisory/Warning
The JMA will evaluate the occurrence of an earthquake ormeasured seismic activity that conforms to one or more of the
scenarios and report to the national government within 2 hours; thenational government will provide instructions to prefectural andmunicipal governments in the designated Nankai region on disastermanagement actions that should be taken during the period (oneweek) in which the major earthquake risk has increased; and, if during
the week-long period a major earthquake does not occur, local
governments in the region are instructed to stand-down (evacuation is
specifically mentioned), but encourages residents to remain alert.
After scientists have assessed the situation and determined thatthe earthquake risk has increased based on one or more of the
scenarios, and in consultation with the national government, the JMA
will release an alert (either an advisory or warning) via a nationwide
press conference. The national government will set up a disastermanagement headquarters and encourage prefectures and municipal
governments to do the same.
As a caveat in presenting recommended planning activities for
local government (including residents) and business and industrialorganizations, the Guidelines for Formulating Disaster Risk
Management Measures Based on Various Nankai Trough Earthquake
Scenarios (1st Edition) on March 29, 2019 caution that in planning,
entities must seek a balance between the risk of an earthquake and8the impact of disaster management measures on the maintenance of
day-to-day life and business activities. And second, those encouraged
to plan for “special earthquake warning information” are advised that
accurate prediction of the timing of an earthquake is impossible, nor isit possible that disaster management measures will assure safety.

IV. Divided and Combined Plans
In our study of municipal planning in the Nankai region, we
discovered that about two-thirds of the jurisdictions have plans withseparate provisions and planned actions depending on whether thealert received from the JMA is a warning or an advisory. The remaining
third had plans with provisions that apply to either type of alert
whether it is a warning or advisory. Either approach to planning iscommendable and selection of one approach or the other will dependon many factors including the size and complexity of the jurisdiction
and other characteristics of the population and capabilities of themunicipal government.
The two types of alerts differ in important respects. Warnings
are issued in situations where a magnitude 8 has occurred in one of
the three Nankai regions and the two other regions will receive amajor earthquake warning. The region affected by the magnitude 8
earthquake will be fully mobilized and responding to what is likely to
be significant casualties and damage. The remaining two regions will
activate plans based on the warning they receive from the JMA. This“partial area rupture” scenario is less likely over time than the
scenarios (magnitude 7 “limited area rupture” or slow slip event)which will prompt an advisory. Thus, advisories, while a lower level ofalert than a warning, will probably be more frequent than warnings.
The one planning action that is sensitive to differences between
divided and combine plans is evacuation of vulnerable populations
which is highly recommended for warnings but optional for advisories.

9

V.

Using the Planning Guide

The planning guide that follows this section includes
recommended actions contained in documents published by thenational government of Japan as well as recommendations developedin other nations with earthquake forecasting systems similar to the
one now being implemented in Japan. This guide also benefited fromanswers to our survey questions provided by disaster managers in the
Nankai region. The information from our survey conducted between
September and December 2022 provided us vital information on theunderstandings and challenges faced by local government officials in
the region for which this guide was specifically designed. Thus, wehope that it will provide information and recommended actions thatmeet the planning needs of municipal governments in the Nankai
region.
We also regard this guide as a “living document” which willcontinue to incorporate best practices as they emerge from theworkshops we will conduct between August 2023 and April 2024. A
further word is in order regarding the guidance provided by thenational government of Japan through the Cabinet Office and thecontents of this planning guide. The national guidance provided in
Cabinet Office White Papers dated 2015, 2019 and 2021 emphasize
evacuation planning for vulnerable populations, urges preparedness
planning by residents and organizations of the private sector andcautions that actions taken should reflect a balance between safety
and maintenance of normal social and economic activities in theregion. The guidance provided by the national government in these
documents is reasonable, appropriate and should be implemented by
local jurisdictions in the Nankai region.

10

Our guidance, as provided in this document, should beconsidered a supplement to government-provided recommendations.
It addresses practices we feel are not contained or adequately
addressed in the national government documents and involve actions
that can be implemented by and within local governments and actions
that require outreach to other organizations, both private and public.
One particularly critical action that we consider a central responsibilityof local governments under a SEWI alert is to provide periodic
briefings for residents regarding the message from the JMA and what
the jurisdiction is doing to promote their safety. A second area which
we emphasize in this document is engagement with local communitybased groups including organizations of the private sector andcommunity-based groups of volunteers that can be mobilized to assist
the jurisdiction with needed emergency period supplies and provide
emergency period assistance with shelter operations, transportation,
evacuation drills and other actions. Finally, we want to encourage
jurisdictions to effectively coordinate with other levels and agencies ofgovernment—with prefectures, neighboring jurisdictions, public andprivate utilities, life line operators and the Japan Meteorological
Agency.

11

Planning Guidelines
Evacuation of Vulnerable Populations
Planning Assumptions and Justification: For jurisdictions withmapped tsunami inundation zones in the Nankai region, evacuation ofvulnerable populations in response to a SEWI warning from the JMA
is highly recommended both by the national government of Japan(Cabinet Office, Government of Japan, 2015, 2019, 2021) and as anaction that, in our view, represents a best practice. While evacuations
are highly recommended if a SEWI warning is issued, evacuations are
discretionary for advisories and Nankai region local governments must
carefully consider whether to recommend evacuations flowing anadvisory. Vulnerable populations are defined as individuals who areunlikely to be capable of evacuating to safe locations in a timely
manner following the occurrence of a potentially tsunami-genic
earthquake. These populations include elderly persons with conditions
that limit mobility, persons with disabilities and others who may
require more time to evacuate.
Special Considerations: Some jurisdictions may have a large
number of residents who require evacuation and many small
jurisdictions may find proactive evacuations in response to a warning
difficult due to limited staffing and logistical challenges. One possible
solution in both planning and execution of an evacuation is to: 1)
encourage evacuees to identify relatives or friends outside tsunami
inundation zones with whom to stay during the warning period; 2)mobilize community-based organizations to acquire training in shelter
management and assist during a warning; 3) develop a program toencourage private sector organizations e.g., local food distributors tocontribute provisions needed at shelters during an evacuation.

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Recommended Actions:Define the demographic categories of people in yourjurisdiction that will require proactive evacuation during awarning. These groups may include:•

Elderly residents unlikely to evacuate the tsunami inundation
area in a timely manner during a tsunami warning•

Persons with disabilities who will require assistance in evacuating
to safety in a tsunami warning•

Persons who reside or work in tsunami inundation zones andcould not reasonably evacuate to safety within 30 minutes of theissuance of a tsunami warning.

Using GIS, map the locations of persons who will be proactively
evacuated in an earthquake warning. If a prioritized evacuation is
anticipated, identify the basis of the prioritization (e.g., geographic,
demographic, etc.) and a strategy for phased evacuation.
Notify those who have been designated as proactive evacuees andprovide them details of plans for their possible evacuation if a SEWI
warning is received. Provide for ongoing communication with thispopulation as their willingness to evacuate, their choice of evacuation
location and their presence in the tsunami hazard zone may change
due to relocation, death or other circumstances.

Conduct a needs assessment that will address the following
considerations:•

The number and location of shelters where those who cannot
relocate to alternative lodging or the homes of family or friends
outside the tsunami inundation zone can be housed during awarning.

13•Given the demographic make-up of those designated in need of
evacuation, consider the needs for staffing and provisions for
shelters (e.g., food service, equipment for persons withdisabilities, medical personnel, etc.).

•

Consider the needs for transportation of evacuees to shelter
locations as many older people and people with disabilities will
not be able to self-evacuate without assistance.

•

Identify means of communicating with potential evacuees to
notify them of the issuance of a warning, the availability ofshelter and transportation to and from shelter locations.

Develop strategies for staffing shelters if jurisdictional resources are
inadequate, for example by trained volunteers from the community or
experienced staff from other jurisdictions.

Identify shelter facilities for evacuees•

Select facilities that are outside the mapped tsunami inundation
zones, but geographically accessible by foot.

•Identify appropriate shelter locations with accessible facilities for
persons with disabilities and those with mobility impairments.

•

Select facilities that will accommodate the desired number of
evacuees. In addition, identify at least a subset of shelters thatwill accommodate evacuee pets as many potential evacuees will
be reluctant to leave without their pets.

•

If the services to be provided include feeding, the facilities
should include necessary kitchen appliances and supplies.

In selection of facilities to be used for shelter, give consideration to theprimary function of these facilities. If schools are selected, forexample, assure to the extent possible, that classes and school
activities can proceed in a normal manner during the evacuation.
Consideration must be given to the fact that proactive evacuees
constitute only a portion of the people who may require shelter if alarge tsunami-genic earthquake occurs, thus, shelter capacity, services
14and supplies must be adequate for all potential evacuees, both those
proactively relocated and those who may need shelter if a tsunami
warning is issued following the occurrence of a large earthquake.

Evacuation signage, guidance material and drills•

An important consideration for tsunami evacuation in general isthat tsunami danger zones, evacuation routes and safe locations
be clearly marked by signage (See Figure 1).

•

Beyond public posting of these zones, potential evacuees should
be provided with information on all aspects of an evacuation,
particularly maps and route information to guide evacuees tosafety if personal means of evacuation are necessary. Essential
in these materials are (Scheer et.al., 2013):
Definition of a tsunami
Identification of the tsunami-related risk
Basic precautions including an explanation of proactive
evacuation and why certain classes of people will be evacuatedunder a special earthquake warning
How to be prepared
How a warning will be communicatedA map of the hazard and safe zones, evacuation routes andlocations of assembly areas and shelters
Examples of tsunami hazard zone signs (See Figure 1)
How to respond to a warning
What to do after an evacuation is canceled.

These items should be incorporated into a single brochure anddisseminated to all residents in the tsunami hazard zones, including15

external workers and employees who are not full-time residents andposted in locations that are frequented by tourists.
Local jurisdictions should conduct evacuation drills at least once per
year. These drills should include proactive evacuation, if feasible.
Figure 4: ISO (International Organization for Standards) approved signage
for tsunami evacuation.

Training, staffing and plan maintenance
Municipal government staff must receive training on plan execution,
the division of function and roles each must play in responding to a
SEWI warning.
In some cases, staffing may be deemed inadequate to execute theplan. In this event, the jurisdiction must consider use of trained
volunteers within or outside the jurisdiction. These volunteers could
function in managing shelters, providing transportation of evacuees toand from shelters or other locations of safety outside the tsunami
inundation areas.
Care must be exercised in maintaining the plan and assuring that
information is current as people move into and out of the tsunami
hazard zones, there occur deaths among potential evacuees,
evacuation shelters and routes change, signage requires replacement
and so on.

Sociological considerations and potential challenges
16Disaster management staff may encounter challenges in that those
identified as potential proactive evacuees may not wish to evacuate
based on a SEWI warning. They are not required by law to do so andmay choose to remain in hazard zones.
While under-evacuation may be a problem among potential proactive
evacuees, the opposite problem may be encountered among those
who are not perceived to be in need of early or proactive evacuation
causing crowding at shelters or unnecessary flight from the hazard
area.
These problems will vary from jurisdiction to jurisdiction depending on
many factors including recent experience of earthquakes and tunamis.

References:
Cabinet Office, Government of Japan. 2015. White Paper,
Disaster Management in Japan, Nankai Trough Earthquake
Measures, 85-93.
Cabinet Office, Government of Japan. 2019. White Paper,
Disaster Management in Japan, Chapter 3 Preparedness for
Nankai Trough Major Earthquakes: Research on Disaster Risk
Management for Anomalous Phenomena, 52-60.
Cabinet Office, Government of Japan. 2021. Summary of“Disaster prevention response study guidelines prepared fordiverse occurrence modes of Nankai Trough Earthquake” (Ver.
1).
S. Scheer, A. Gardi, R. Guillande, G. Eftichidis, V. Varela, B. de
Vanssay,L. Colbeau-Justin. (2013). Handbook of Tsunami
Evacuation Planning. European Commission Joint ResearchCentre Institute for the Protection and Security of the Citizen.
Ispra, Italy. http://ipsc.jrc.ec.europa.eu/

17Residential Home Preparedness
Planning Assumptions and Justification: Providing residential
home preparedness for disaster should be a routine function of local
government; however, during a period of enhanced seismic activity
which has triggered an earthquake advisory or warning, publicattention with be focused on the hazard, providing an opportunity toenhance residential preparedness for a major earthquake and tsunami.
This opportunity should not be missed and local jurisdictions should
provide a prioritized list of actions that can be taken by residents to bebetter able to respond effectively to both the alert and the earthquake,
if it occurs. Residents and businesses in the Nankai region are urged toreview individual and corporate preparedness in the guidelines
provided by the government and in this guide.
Special Considerations: In our survey conducted last year, we
discovered that residential preparedness was a feature of most SEWI
plans, but two actions, how to respond when the shaking of anearthquake is encountered and fire suppression were not sufficiently
emphasized in preparedness recommendations to residents. Below arewhat we consider a comprehensive list of residential preparedness
actions for residential households (Japan Times, no date;
Recommended Actions:

Before the Earthquake:
Residents should be familiar with evacuation routes from home, workand children’s school as well as places frequently visited. Recommend
having paper maps with these routes.
Residents should prepare an earthquake kit that includes the following
items.
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Phone numbers of family and friends and emergency contacts.
Foreign visitors should have the phone number of theirrespective embassies.
Flashlight (spare batteries or charger)
Portable radio (spare batteries or charger)
First aid kit
Blankets
Important documents (passports, bank book, deed to home andcash)
Extra clothes including rainwear
Residents should have water and non-perishable food for at least one
week (check for expiration dates at least annually)
Residents should have a fire extinguisher in their homes and know
how to use it.
Residents should secure furniture that may topple and cause injury or
inhibit egress. Included are tall bookcases, wall mounted mirrors andartwork, large electronics including kitchen appliances that could fall
during strong shaking of an earthquake. Hardware stores have avariety of bracing, strapping and tools for fastening and securing
household appliances and furniture.
Remind residents that Japan has an earthquake early warning systemand that an app can be downloaded that may provide them a few
seconds to a few tens of seconds warning before they feel groundmotion from an earthquake.
https://www.jma.go.jp/jma/en/Activities/EEWLeaflet.pdf

19Self-Protective Actions: Recommended response will varydepending on a resident’s location when an earthquake
occurs.
If at home, work or school, the best response is to move away fromdangerous locations like widows and falling hazards and take coverunder sturdy furniture. As most buildings in Japan are earthquake
resistant, there is no need to rush outside and standing in doorways
does not provide the level of protection many people believe.
Figure 5: Self-protection in an earthquake

If driving a vehicle, gradually pull to the side of the road and stop;
remain in the car. Be sure not to stop beneath electrical wires andaway from buildings.

If working outside, move away from overhead electrical wires andother potential hazards.

Post-Earthquake Actions:
If residents live in a coastal area, they should be instructed to move tohigh ground immediately without waiting for an official tsunami
evacuation alert. They can check their portable radio or phone (if it’s
online) for updates later.
If they are trapped under rubble, recommend that they cover theirmouth. Bang rhythmically on a pipe or wall, or send a text for help
instead of shouting. They will conserve energy and oxygen by doingso.

20

If phone lines are down, try other applications or texting services.
Social media use is another method of communication in an
emergency.
When evacuating buildings, don’t use the elevators, even if it seems
like the shaking has stopped. Keep in mind the likelihood ofaftershocks and use the stairs.
Turn off your gas immediately if you smell what may be leaking gas(and be careful about flames from lighters until you confirm there
hasn’t been a gas leak). If you need to evacuate your home, turn off
your circuit breaker.
References
Japan Times (no date), “Japan earthquake tips:“What to do before, during and after anearthquake”, https://www.japantimes.co.jp/japandisaster-information/earthquake-preparation/
Accessed May 30, 2023.
Japan Meteorological Agency (no date). ”Earthquake Early
Warnings: Forecasts of strong motion caused
earthquakes https://www.jma.go.jp/jma/en/Activiti
es/EEWLeaflet.pdf

21

Alert Period Communications (with Residents)
Planning Assumptions and Justification: Typically, this set ofactions would be included under the general topic of actions to betaken within the jurisdiction, but these actions are particularly
important to SEWI planning and are neither mentioned in the national
governments recommended actions nor were they frequently reported
as actions included in SEWI plans in our survey of local government
planning for SEWI alerts. Specifically, these actions consist of regularbriefings for residents to first announce the issuance of an advisory or
warning from the Japan Meteorological Agency, detail any changes inthe status of the alert and announce, in coordination with the JMA, thecancelation of an alert.
Special Considerations: Residents of a jurisdiction will look to local
government for information when a SEWI alert (advisory or warning)has been issued. They will want to know the nature of the risk, thelikelihood that an earthquake will occur during the alert period, what
the local government has done to mitigate the risk and what theyshould do during the alert period. While much of this information will
come from sources outside the local government, residents will look totheir elected representatives at the local level to coordinate disparate
information and provide a consistent narrative that considers the local
context.
Recommended Actions:
Identify a spokesperson, preferably a single person and someone in ahigh-level elected position (e.g., mayor) or a well-known andrespected municipal official who will provide daily briefings toresidents. The attitudes conveyed should be confident, empathetic andengaged.
Establish a schedule of regular briefings, at least once daily over theperiod of the alert (several days).

22

The spokesperson will provide information regarding the alert(advisory or warning from the JMA) based on information received
from official sources including the JMA, national government anddisaster management officials within the municipal and prefectural
governments. This information will be presented in simple
straightforward language and should include the following:•

Accurately relay the alert as presented by Japan Meteorological
Agency•Convey the risk to the jurisdiction which may include strong
ground shaking from an earthquake and a tsunami if thejurisdiction is on the Pacific Coast or has mapped tsunami
inundation zones.

•

Indicate that the municipal government has a plan for a SEWI
alert and has taken steps to protect residents if the alert resultsin the hazards indicated in the alert.

•

In general terms, provide an overview of what the plan entails•

Report how the plan is being executed based on regular reports
from the jurisdiction’s staff who are involved in plan activationand implementation within the jurisdiction.

•

Dispel rumors and misinformation and be sensitive to theconcerns and issues communicated to municipal staff fromresidents.

•

Remind residents that there are actions that they can take topromote their safety during the alert (See Section II). If there
are volunteer opportunities during the alert, announce these anddetails of participation.

You have many communication methods to choose from, including inperson events (news conferences), print and broadcast media, andInternet and social media. Each has advantages and limitations
depending on your communication objective and the intended
audience. To use media in a timely fashion, learn local media news
cycles and deadlines.

23

Be sure to provide information from the briefings in formats that reachpeople with disabilities as these residents may require proactive
evacuations if the jurisdiction has tsunami inundation zones.
If there are non-Japanese speaking communities within thejurisdiction, be sure that there is a means for them to receive criticalinformation in the language they speak.
One way to help prevent errors or omissions that can occur in
moments of urgency is to use templates that are tailored to threats
and hazards likely in your warning area. Using a template thatincorporates pre-approved language can reduce delays in issuing alerts
and warnings. Another advantage is that, if you need to use alanguage in addition to Japanese, your templates can be translated inadvance. Sample alert messages are contained in Appendix B.
Effective alerts and warnings are those that result in members of the
public taking recommended actions to protect themselves. To help
ensure that messages are effective, they must be issued in a timely
manner and should include the following components:
Figure 6: Some useful content for announcing an advisory or warningin the first briefing (US Federal Emergency Management Agency,2014).
Specific hazard: What hazard is threatening? What are thepotential risks for the community?
Location: Where will the impacts occur? Describe the location
so those without local knowledge can understand their risk.
Timeframes: When will it arrive at various locations? How long
will the impacts last?
Warning source: Who is issuing the warning? Identify an
official source with public credibility.

24

Magnitude: What impact is expected and how bad is it likely toget?
Likelihood: How probable is occurrence of the impact?
Protective behavior: What protective actions should people
take and when? If evacuation is called for, where should
people go and what should they take with them?

25

Coordination and Cooperation
Assumptions and Justification: In a major disaster, a jurisdiction
may find itself overwhelmed with insufficient personnel and resourcesto effectively respond, and require the assistance of other levels ofgovernment (prefectures and national government). While othergovernment entities are a reasonable and appropriate source ofassistance, a local government may also draw on internal sources ofassistance from private sector organizations and community-basedorganizations. In facing the near-term potential for responding to amajor earthquake and tsunami, local governments in the Nankai
region must consider both sources of possible assistance. These
measures received meager attention in government guidelines for a
SEWI alert, but we feel that coordination and cooperation between
levels of government and within a jurisdiction among major local
stakeholders is essential.
Special Considerations: Based on our study of SEWI planning
among local governments in the Nankai region, we know that smaller
jurisdictions are challenged to carry out SEWI planning due to resourceand personnel shortfalls. Thus, it is of critical importance to reach out
to both governmental and non-governmental sources of assistance.
Recommended Actions:
Consider forming Memoranda of Agreement with jurisdictions outside
the Nankai region that may provide disaster management trained
personnel to assist in implementing SEWI related actions during awarning or advisory.
Assure that plans for responding to a SEWI alert are consistent withcomparable plans of the prefecture in which the jurisdiction resides.
Identify organizations at the prefectural level with which thejurisdiction must interact during a SEWI alert (e.g., the prefectural
JMA office).

26

The print and broadcast news media that serve your jurisdiction will be
important sources for communicating with residents during a SEWI
alert. Reach out to these media and include coordination with them in
SEWI response plans.
Social media will also be important means of communicating
jurisdictional actions during a SEWI alert. Someone in your jurisdiction
should be familiar with how these media can be employed in a SEWI
alert and mobilized, as needed.
Identify organized community-based groups and private sector
organizations within the jurisdiction that are willing and capable ofassisting the jurisdiction during a SEWI alert.
•

Once non-governmental organizations within the jurisdiction are
identified, determine whether members of the organizations
require training in the tasks they are expected to perform.

•

Provide the training considered necessary for the communitybased organization to perform functions assigned, as deemednecessary.

27

Internal Mobilization
Assumptions and Justification: Given the short-term nature of a
SEWI alert (advisory or warning), it will be of critical importance toquickly assemble disaster management personnel and representativesof all departments and agencies with roles in response to an alert. The
national government recommends that a disaster management
headquarters be established which will serve as a coordination center
for information gathering decision-making, coordination andemergency period information provided to residents.
Special Considerations: Our study revealed that a great majority ofmunicipalities have provisions in their SEWI plans to mobilize a
response and set up a disaster management headquarters; however,few jurisdictions reported having conducted drills or exercises of their
SEWI plans. In addition, it appears that coordination with agencies andorganizational entities outside the jurisdiction including themobilization of community-based groups has not been a priority inmany SEWI plans.
Recommended Actions:
Carefully consider the roles that will be performed in a SEWI responseby departments and agencies within the jurisdiction. Conduct a
training seminar in which departmental representatives who willassume these roles become acquainted with their responsibilities when
the SEWI plan is activated for an advisory or warning.
Identify the location that will serve as a disaster headquarters during a
SEWI alert and for response if an earthquake occurs. If this location isan established emergency operations center (EOC) it should have all of
the communications, monitors and other equipment needed for an
emergency response. If there is no established location that is soequipped, consider designation of a location and acquiring thenecessary equipment.

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The primary functions of staff in the disaster headquarters
include:•Collecting, analyzing and sharing information;•

Supporting resource needs and requests, including allocation andtracking;•

Coordinating plans and determining current and future needs;and•In some cases, providing coordination and policy direction.

In addition to representatives within the jurisdiction familiar with theSEWI plan and who have well-defined roles to perform during a SEWI
alert, consider other organizations within the jurisdiction whose
presence in the disaster headquarters would be useful including
representatives of the prefectural government, utility companies,
lifeline operators and major employers in the jurisdictions.
Develop a reporting and briefing protocol among representatives at thedisaster headquarters. Compile a situation assessment report and keep
it updated on a regular schedule as the situation evolves over theperiod in which an alert is in force.
A high priority activity will be to establish briefings for residents of thejurisdiction very soon after an alert has been declared, ideally holding
the first briefing within an hour of the alert being issued. Subsequent
briefings should be scheduled on a regular basis, at least once a day
and as important new developments occur.
Develop a strategy for public information regarding the cancellation ofan alert as announced by the Japan Meteorological Agency. Since thebasis for a SEWI alert is the enhanced short-term likelihood of anearthquake, the downgrade of a warning to an advisory or thecancellation of an alert does not mean that an earthquake will not
happen and residents should be informed that personal earthquake
preparedness should be maintained given the long-term probability ofa large earthquake in the region.
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References
Federal Emergency Management Agency (2022). Emergency
Operations Center How to-Quick Reference Guide.
www.fema.gov/sites/default/files/documents/fema_eoc-quickreference-guide.pdf

30Dealing With Non-Essential Activities
Assumptions and Justification: While seismic activity in the Nankai
region has raised the short-term likelihood of a major earthquake andpossible tsunami and a SEWI alert has been issued, your jurisdiction
may have been minimally impacted by this activity. Thus, your mainconcern is to be prepared and response ready if additional earthquakes
occur. The national guidelines do not identify specific actions forpostponement or cancellation, but both the national government andour recommendation is to seek a balance between safety andmaintaining normal or near-normal social and economic activity in thejurisdiction. Postponement or cancellation of activities within thejurisdiction in response to a SEWI alert are recommended in only a few
situations.
Special Considerations: There may be situations in which ajurisdiction would recommend postponing or delaying activities for the
short period in which a SEWI alert is in force, typically a period of afew days. Some of these situations are noted below.
Recommended Actions:
Scheduling large assembly events for venues in mapped tsunami
inundation zones during an alert may be discouraged.
Residents may be encouraged to consider whether elective surgeries
or non-emergency medical procedures be scheduled during the SEWI
alert period.
Jurisdictions may advise residents and organizations to consider
whether buildings, bridges and other structures known to bevulnerable to earthquakes be avoided during a SEWI alert. If so, thesestructures must be identified.
Employees who work or deliver goods within a mapped tsunami
inundation zone should be encouraged to be especially aware oftsunami evacuation routes during a SEWI alert.
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High risk (hazardous) materials processing or maintenance activities
may be considered for postponement during a SEWI alert.
Disaster management organizations and other organizations withcritical disaster response functions should consider cancellation ofleaves for employees during a SEWI alert.

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Appendix
Sample SEWI Messages
Earthquake Advisory/Warning Message (Sample Message)

Following the <date of event> magnitude <moment
magnitude>earthquake in <location of event>, the Japan
Meteorological Agency (JMA) has conferred with scientists
knowledgeable about this region’s seismic history andpotential. Based on these discussions, the JMA has issued anearthquake <advisory/warning> for the Nankai region
indicating that an increased likelihood exists for continued
seismic activity for approximately <number of days>. This
activity could involve earthquakes as large as, or somewhat
larger than, the <date of event>and could cause damage
and possibly a tsunami. Local governments in the Nankai
region, including <name of jurisdiction>, have activatedplans to promote the safety of residents and businesses.

Earthquake Advisory/Warning Period Ends (Sample
Message)
The <number of days>-day earthquake <advisory/warning>issued by the Japan Meteorological Agency on <date of33

issuance> has ended as of <date and time>. The likelihoodof earthquake activity in the Nankai Region is believed byscientists to have decreased such that normal social andeconomic activities may resume. Nevertheless, residents areadvised to remain aware that large earthquakes may occur
at any time and preparedness should be maintained. <nameof jurisdiction> will remain in close contact with the JMA in<prefecture name> for any changes that may requirereissuance of an earthquake advisory or warning.

Adapted from The California Earthquake Advisory Plan
(1990). California Office of Emergency Services,
Sacramento, California, USA.

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