International Journal of Disaster Risk Reduction 21 (2017) 323–330

Contents lists available at ScienceDirect

International Journal of Disaster Risk Reduction

journal homepage: www.elsevier.com/locate/ijdrr

The 2016 Fukushima earthquake and tsunami: Local tsunami behavior and MARK recommendations for tsunami disaster risk reduction ⁎ Anawat Suppasria, , Natt Leelawata, Panon Latcharotea, Volker Roebera, Kei Yamashitaa, Akihiro Hayashia, Hiroyuki Ohirab, Kentaro Fukuic, Akifumi Hisamatsub, David Nguyenb, Fumihiko Imamuraa a International Research Institute of Disaster Science (IRIDeS), , Japan b Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Japan c Department of Civil Engineering and Architecture, School of Engineering, Tohoku University, Japan

ARTICLE INFO ABSTRACT

Keywords: The 2016 Fukushima earthquake and tsunami presented several new issues of tsunami generation mechanism 2016 Fukushima earthquake and tsunami and propagation, as well as of organizational responses such as evacuation procedures and dissemination of Tsunami disaster risk reduction tsunami warning. This study focuses on explanations to issues of public interest based on the experiences during Tsunami mechanism the 2016 tsunami: (1) Despite Fukushima Prefecture's proximity to the earthquake's epicenter, why was the Tsunami runup largest wave observed in the neighboring ? (2) Why was the second wave of the tsunami larger Tsunami warning than the first? (3) Why was the tsunami advisory elevated to a tsunami warning in Miyagi Prefecture? (4) Why did tsunami intrusions into rivers occur? (5) And why were local tsunami runup values much higher than the broadcasted tsunami amplitudes from local tide gauges? In the wake of the 2011 Great East Japan earthquake and tsunami, this study also points out remaining problems and new perspectives related to tsunami disaster risk reduction. These include tsunami warnings and advisories by agencies, the fact that tsunami waves are higher near the coast than in the open ocean, and refraining from being close to rivers in case of a tsunami. Based to Japan's experiences with disaster mitigation, lessons were learned from numerous events that could lead to revisions and improvements of current warning systems and provide useful guidelines for other countries.

1. Introduction Advisories at 06:02 JST. This message contained tsunami warnings for Fukushima Prefecture and Tsunami Advisories for the Pacific coast- On 22nd November 2016 at 05:59 JST (UTC+09:00), a large lines of Aomori Prefecture, Iwate Prefecture, Miyagi Prefecture, Ibaraki earthquake occurred off the east coast of Japan, near Fukushima Prefecture, and Kujukuri and Sotobo area in Chiba Prefecture. By 07:26 Prefecture. The magnitude of this normal-fault earthquake was re- JST, the Tsunami Advisories included the Uchibo Area of Chiba corded at Mj 7.4 (from the originally announced Mj 7.3) by the Japan Prefecture and Izu Islands. At 08:09 JST, Miyagi Prefecture were Meteorological Agency (JMA) at a depth of 25 km (from the originally elevated to a Tsunami Warning. At 09:46 JST, the Tsunami Warnings announced 10 km) [1]. Meanwhile, Mw 6.9 at depth 11 km was given were downgraded to Tsunami Advisories which covered Iwate by the United States Geological Survey (USGS) [2]. The shock had a Prefecture, Miyagi Prefecture, Fukushima Prefecture, and Ibaraki maximum seismic intensity of “5-” in Japanese “Shindo” scale which Prefecture. Finally, the JMA lifted all Tsunami Warnings and corresponds to VII on the Mercalli scale [1]. Advisories at 12:50 JST. As the maximum tsunami amplitude of Based on JMA data, as of 07:30 JST, further seismic activity was 1.4 m was measured at port, this was the highest tsunami recorded, which include one instance of categorized Shindo 5-, three event since 2011. instances measured at Shindo 3, seven of Shindo 2, and seven of This article provides preliminary findings of the aforementioned Shindo 1 [1]. JMA stated this seismic event was an aftershock of the issues that should be further investigated in future studies. Although 2011 Great East Japan Earthquake [1]. this earthquake and tsunami event only caused minor damages with no According to Table 1, the JMA issued its first Tsunami Warnings/ human casualty, there are some remaining and new issues for tsunami

⁎ Corresponding author. International Research Institute of Disaster Science (IRIDeS), Tohoku University, Aoba, Aramaki-Aza, Aoba 468-1, Sendai 980-0845, Japan. E-mail address: [email protected] (A. Suppasri). http://dx.doi.org/10.1016/j.ijdrr.2016.12.016 Received 20 December 2016; Accepted 27 December 2016 Available online 17 January 2017 2212-4209/ © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/). A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330

Table 1 Tsunami warnings and advisories. (For interpretation of the references to color in this table, the reader is referred to the web version of this article.). Source [1].

*Note: Red indicates tsunami warning. Yellow indicates tsunami advisory. disaster risk reduction perspectives that should be pointed out and The orientation of the two nodal planes obtained from USGS (2016) correctly understood before the next tsunami event as summarized in (Fig. 2) were used for our preliminary computed initial sea surface the following section. elevation [6] based on a scaling empirical formula [7] and distribution of aftershocks [8]. Another extraordinary issue for this earthquake was 2. Emerging tsunami related issues that the fault size estimated by the mentioned scaling empirical formula is rather large with smaller slip (fault size =39×17 km2 and This section discusses five issues of public interest related to this slip =1.4 m) as shown in Fig. 2(a) but smaller fault size with larger slip tsunami event. First, while the epicenter of the earthquake was close to based on the distribution of aftershocks (fault size =20×10 km2 and Fukushima Prefecture, the highest tsunami wave was recorded in slip =4.0 m from [8] as shown in Fig. 2(b). Sendai Port, located further north in Miyagi Prefecture. Second, the second wave, rather than the first, was the highest wave. Third, the Table 2 tsunami advisory was upgraded to a tsunami warning in Miyagi Observed maximum tsunami amplitude along the east coast of Japan. Prefecture. Fourth, the local tsunami runup was observed to be higher Source [1]. than the observed tsunami amplitude at the tide gauge in Sendai Port. Finally, the tsunami propagated into rivers as undular bores. Location Amplitude (m) Time (JST)

Iwate Prefecture Kuji port 0.8 07:54 2.1. The highest observed tsunami was in Sendai, Miyagi Prefecture Miyako 0.4 08:09 rather than near the earthquake's epicenter, off Fukushima Prefecture Kamaishi 0.2 08:58 Ofunato 0.4 07:56 The maximum tsunami amplitudes observed at tide gauge stations Miyagi Prefecture Ayukawa 0.8 07:39 along the east coast of Japan showed that the maximum tsunami Ishinomaki port 0.8 08:11 amplitude of 1.4 m was observed at Sendai Port in Miyagi Prefecture Sendai port 1.4 08:03 while the maximum observed tsunami amplitude in Fukushima Prefecture was only 0.9 m as shown in Table 2 [1]. This is due to the Fukushima Prefecture Soma 0.8 07:54 Onahama 0.9 07:06 fact that despite the epicenter being near Fukushima, its fault plane (strike angle) was perpendicular to Sendai, while parallel to other areas Ibaraki Prefecture Oarai 0.6 06:49 in Fukushima. The strike angles of two nodal planes (45–60 and 220– Kashima port 0.5 07:08 232) from all well-known sources of fault mechanism are similar [1–5]. In other words, the tsunami wave energy was spread directly towards Chiba Prefecture Okitsu 0.3 09:06 Mera 0.3 09:03 coastal areas near Sendai including wave refraction into Sendai bay. Tokyo Yaene 0.3 07:13 (Fig. 1).

324 A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330

Fig. 1. Location map, epicenter, location discussed in the paper.

Another issue that was discovered is related to the fault size and slip should examine this kind of wave amplification. In addition, wave of this event is the earthquake magnitude. JMA finally announced Mj shoaling, refraction, and dispersive effects should also be considered 7.4 (equal to Mw 7.2 based on [9] while estimation from other inside Sendai bay. international sources [2,4,5] was Mw 6.9. The equivalent fault sizes and slips for these two different magnitude are 39×17 km2 and 1.4 m 2.3. Tsunami threat level was elevated from “advisory” to “warning” for M 6.9 whereas 55×21 km2 and 2.3 m for M 7.2. Such small w w in Miyagi Prefecture difference of 0.3 Mw can cause significant result of the predicted tsunami height in case of small to moderate tsunami like this event First, it is necessary to understand the current classification of the which is related to tsunami warning system. tsunami warnings and advisories utilized in Japan. JMA is an official agency that monitors and issues warning messages for all natural disasters including tsunamis [12]. Due to the experiences with the 2.2. The second wave was the largest 2011 Great East Japan Earthquake and Tsunami, the terminology and classification of warnings in Japan were modified [13–15]. Table 3 It is commonly understood for ordinary persons in Japan that the shows the current warning classification and description of tsunami first wave of a tsunami is the largest wave while many tsunamis showed criterion [15,16]. In order to limit complications, a wider range has the second or third wave to be the highest [10]. However, the second been applied to this classification system. When a tsunami with the wave observed at Sendai Port was the largest wave as shown in Fig. 3. height ranging from 20 cm to 1 m is expected, a tsunami advisory is In addition to the fault orientation, which focused the tsunami into issued (indicated by a yellow color; advisory). When a tsunami is Sendai Bay, wave reflection and refraction were other contributors. expected to be between 1 m and 3 m, a tsunami warning is issued Sendai Bay (Fig. 4) is a very shallow (average water depth is less than (indicated by a red color; warning). If a tsunami is expected to be 50 m) and wide bay. Due to this coastal topography, the waves are greater than 3 m, a major tsunami warning is issued (indicated by a amplified due to wave shoaling and refraction inside the bay. Also, purple color; emergency warning). superposition of the incoming and reflected waves from the Fukushima At the beginning, JMA expected the arrival of the tsunami wave in coast played a role. As shown in Fig. 4, the first wave crest (red) hit Fukushima Prefecture to be higher than 1 m; therefore a tsunami Fukushima Prefecture (after 20 min) and reflected from the steep coast warning was issued for that prefecture. At 08:09 JST due to the (another 20 min later). The first wave trough (blue) hit Sendai Port observed 1.4 m tsunami height at Sendai Port, the tsunami advisory of after 60 min and the first wave crest arrived at Sendai Port after Miyagi Prefecture had to be elevated to a tsunami warning (over 1– 80 min. The reflected wave from Fukushima approached Sendai Port 3 m). after 100 min and superimposed with the second incoming waves after 120 min. Another explanation for the unexpectedly high tsunami wave inside 2.4. Local tsunami runup was higher than the observed tsunami Sendai Bay might be connected to the wave resonance with the amplitude from tide gauge at Sendai port fundamental oscillation mode. The amplification of a tsunami wave inside a bay is highly dependent on the tsunami wavelength, which can In general, the tsunami height can be amplified or enlarged up to 2– excite the natural oscillation inside the bay. Therefore, further research 4 times during the runup process. Based on our preliminary survey,

325 A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330

Fig. 2. Orientation of two fault planes based on USGS [2] and our computed initial sea surface elevation based on a scaling empirical formula (a) (fault size =39×17 km2 and slip =1.4 m) and distribution of aftershocks (b) (fault size =20×10 km2 and slip =4.0 m). tsunami runup higher than the observed tsunami wave amplitude of 2.5. Tsunami intrusion into rivers 1.4 m at Sendai Port was measured at several sites. In the Miyato area of Higashi-Matsushima City in Miyagi Prefecture, tsunami runup In addition to issues regarding tsunami propagation offshore and heights of more than 2–3 m were found caused by nearshore processes inundation on land, tsunami intrusion into rivers were also observed. over the coastal topography. For example, in Ohama fishing port, a This phenomenon was clearly observed at Sunaoshi River in Tagajo runup higher than 3 m was measured at an inclined driveway of a City, where the tsunami propagated over 3 km into the river [17]. The resident's house as shown in Fig. 5. The reasons for such high runup tsunami speed is estimated to be about 14 km/s and the maximum are (1) the shape of the port trapping the first wave before the arrival of rising of the river level reached 0.9 m (0.6–0.7 m above the normal the second wave, (2) the tsunami occurred during a flood-tide stage level) [17]. This phenomenon was filmed by many eyewitnesses and that help pushing the wave inside the port and (3) the existing gentle interested many local residents. In the case of the 2011 tsunami, the sloop that assisted wave runup. river tsunami overflew the embankment of the Sunaoshi River with more than 2 m of inundation depth that led to damages along many areas along the river [18].

Fig. 3. Observed tsunami waveform at Sendai port [11].

326 A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330

Fig. 4. Tsunami propagation from Fukushima to Sendai Bay [6].

Table 3 3. New and remaining perspectives towards disaster risk Current Tsunami Warnings and Advisories Classification in Japan. reduction (DRR) Source: JMA [16]. 3.1. Wait for the official cancellation of a tsunami warning Estimated tsunami height Warning classification Tsunami warning classification Until now, it is still difficult to include all possible earthquake fault 10 m < h Emergency warning Major tsunami warning mechanisms and high-resolution coastal topography in a tsunami 5m

3.2. Tsunami warning and broadcasting

As the responses to the warnings depend on the way that the message is interpreted and understood, it is necessary to focus on the issues related to the warnings and broadcasting of this event. We can

Fig. 5. Tsunami runup T.P. +4.1 m (yellow dashed line) and inundation height T.P. +3.6 m (blue dashed line) at Ohama fishing port, Miyato area of Higashi-Matsushima city, Miyagi Prefecture. The runup and inundation heights were measured with a laser range finder, staff, and Promark GPS device. The picture was provided by Miyagi Prefecture Fisheries Cooperative Association (JF Miyagi) Miyato western branch. (Picture taken date: 22/11/2016). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

327 A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330

Fig. 6. Breaking news broadcasted on NHK World on November 22, 2016. Note: Source: [21]. see significant changes in the warning system, especially the broad- this disaster event. casting process, compared to those utilized in the 2011 Great East Moreover, Social Networking Services (SNS) played an important Japan Tsunami. Broadcasting warning messages through television, role during this tsunami event. For example, SNS was used to confirm radio, and speakers only in areas expected to be affected, as done in people's safety. Facebook provided the Facebook Safety Check, which 2011, lead to insufficient results due to blackouts and the loss of covered a far-reaching area that even included Tokyo [23]. Another personnel and broadcasting vehicles in the tsunami [19]. example was Twitter, which was used to retweet disaster information. NHK is Japan's national public broadcasting organization, with Some people shared their recorded videos showing the river tsunamis NHK World representing their international broadcasting service. NHK in some areas. World broadcasted news of the 2016 earthquake and tsunami in English from the beginning of the event. The reporters used English 3.3. Local tsunami on land can be higher than the observed tsunami language for all programs of NHK World. The news ticker was updated at sea over nearly the entire period. During this news coverage, some real- time breaking news, such as press releases from JMA, were simulta- In general, many people do not understand the difference between neously interpreted from Japanese to English. Fig. 6 shows the the two types of tsunami measurements, (1) tsunami wave amplitude screenshot of an NHK World broadcast on the day of the event. In measured at a tide station and (2) tsunami runup measured on land. contrast to the calm voice used during the 2011 tsunami, terms such as These two types of measurements should not be confused or directly “Evacuate immediately!”, “Tsunami! Evacuate!”, etc. were used to compared because their definitions are different. Nevertheless, this can warn people to evacuate from locations expected to be hit by the be a lesson as the tsunami runup is higher than the observed tsunami tsunami. Also, some phases such as “Please remember the Great East amplitude. Therefore, people should keep this fact in mind and should Japan Earthquake and move to higher ground”, were used to remind act or evacuate accordingly. The maximum observed wave amplitude the audience of the 2011 devastation [20]. The warnings were also announced during a tsunami warning is not equal to the maximum released in Chinese and Korean languages [19]. wave runup. Often, as in the case of this event, the maximum wave In addition, Japanese Prime Minister Shinzo Abe included the runup is much higher than the observations at local tide level. following message in his opening statement during his visit to It is also important to emphasize on the point that a tsunami is Argentina, which was broadcasted live. nothing to play with. Beachgoers, hobby fishermen, and surfers are “Just now a strong earthquake struck off the coast of Fukushima advised to follow instructions from emergency managers and local Prefecture and a tsunami warning was issued. I gave instructions authorities and stay off beaches until the “all clear” sign is given. to the relevant authorities to provide the public with information Tsunami waves should not be confused with regular swell waves. regarding tsunamis and evacuation in a timely and accurate Tsunamis are not surfable waves because they do not break like regular manner, swiftly grasp the damage situation, and make all-out swell waves. In contrast, tsunamis behave like quickly-rising extreme efforts toward emergency measures in response to the disaster. tides and the water is often laden with debris. Attempts to surf To reinforce this, I also directly instructed the Chief Cabinet tsunamis quickly end deadly. Secretary to take all possible measures. …” [22] His statement directed people's focus to the event as well as it 3.4. Do not get close to a river tsunami supported residents to continue following the information related to As mentioned in sub-section 3.2, some people tried to get close to

328 A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330 rivers to film the tsunami. Although, it was fortunate that the river Association (JF Miyagi) Miyato western branch for their information tsunami did not lead to overtopping of the embankment, it nevertheless on the tsunami trace in Ohama fishing port, Miyato Island and all other highlights the risk people can expose themselves to. Future tsunamis members of the Tsunami Engineering Laboratory, IRIDeS, Tohoku may not only overtop and destroy the river embankment as seen in University for their cooperation during an emergency response of this 2011, but could also cause human casualties and property damage. tsunami event. This research was funded by Willis Research Network Thus, no matter what tsunami size is expected, people should stay clear (WRN), Tokio Marine & Nichido Fire Insurance Co., Ltd. and the of rivers. internal budget of IRIDeS (Hazards and Damage Evaluation and Mitigation unit), Tohoku University. Volker Roeber is greatly appre- 4. Conclusions ciating the support from the Japan Society for the Promotion of Science (JSPS), KAKENHI Grant Number 15K06224 (Tohoku University). Following the Sendai Framework for Disaster Risk Reduction 2015–2030 [24], in order to reduce risk, it is important for people to References understand and to be prepared for disasters. This paper provides an explanation of the significant issues related to the 2016 Fukushima [1] Japan Meteorological Agency (JMA), Press releases (in Japanese). 〈http://www. Earthquake and Tsunami. It was an event, which highlighted many jma.go.jp/jma/press/1611/22b/kaisetsu201611221100.pdf〉, 2016 (accessed 22. 11.16). interesting characteristics of the tsunami itself for future research and [2] United States Geological Survey (USGS), M6.9–37 km ESE of Namie, Japan. also illustrated the responses from Japanese authorities, which learned 〈http://earthquake.usgs.gov/earthquakes/eventpage/us10007b88#executive〉, their lessons from the 2011 Great East Japan Tsunami. 2016 (accessed 22.11.16). [3] National Research Institute for Earth Science and Disaster Resilience (NIED), Fault In addition to these explanations, some instructions are suggested mechanism analysis by F-net (in Japanese). 〈http://www.hinet.bosai.go.jp/topics/ in this paper. People should wait until the official cancellation is off-fukushima161122/?LANG=ja & m=mt〉, 2016 (accessed 07.12.16). announced before returning to areas under tsunami threat. It is [4] GEOFON, NearEast Coast of Honshu, Japan. 〈http://geofon.gfz-potsdam.de/ 〉 possible that the biggest wave will not necessary be the first wave. eqinfo/event.php?Id=gfz2016wxkb , 2016(accessed 22.11.16). [5] Global CMT catalog, Global CMT Web Page. 〈http://www.globalcmt.org/〉, 2016 This paper gives a clear understanding of tsunami wave amplitude (accessed 23.11.16). measurements and tsunami runup measurements. While the an- [6] F.Imamura, A.Suppasri, N.Leelawat, P.Latcharote, A.Hisamatsu, F.Makinoshima, nounced tsunami wave amplitude is small, the runup at the coastal M.Watanabe, H.Ohira, Y.Hirasawa, N.Togawa, N.Hasegawa, T.Otake, R.Baba, K. Fukui, S.Sato, K.Yamashita, A.Hayashi, Y.Abe, Modeling the Tsunami of 22 area can be higher and more powerful. The tsunami warning database November 2016 in Fukushima. 〈http://www.tsunami.civil.tohoku.ac.jp/hokusai3/ has still limitations related to the fault mechanisms, location, and J/events/20161122_fukushima/20161122_fukushima.html〉, 2016 (accessed 06. detailed geography. Therefore, changes in the categorization of warn- 12.16). [7] B.C. Papazachos, E.M. Scordilis, D.G. Panagiotopoulos, C.B. Papazachos, ings should be expected depending on real time tsunami observations. G.F. Karakaisis, Global relations between seismic fault parameters and moment While many countries focus on warning system development magnitude of earthquakes, Bull. Geol. Soc. Greece XXXVI (2004) 1482–1489. [25,26], it is still important to look into how these messages are [8] Y.Fujii, K.Satake, Off-Fukushima Tsunami on Nov. 21. 〈http://iisee.kenken.go.jp/ staff/fujii/Fukushima2016/tsunami.html〉 (accessed 12.16.2016), 2016. disseminated. The lessons learned from the broadcasting of the [9] E.M.Scordilis, Globally valid relations converting Ms,mb and MJMA to Mw, Nato warnings for the 2011 Great East Japan Tsunami led to changes in Advanced Research Workshop on Earthquake Monitoring and Seismic Hazard broadcasting methods. More insistent terms were used instead of the Mitigation in Balkan Countries, Borovetz – Rila Mountain – Bulgaria, 11-17 September, 2005. previously used softer and calmer tones. Using terms related to the [10] Y.Yamazaki, V.Roeber, V.K.F.Cheung, T.Lay, Modeling the 2011 Tohoku-oki 2011 tsunami invoked a sense of urgency to evacuate as they still tsunami and its impacts on Hawaii, in: Proceedings of OCEANS 2011, Hawaii. reminded people of the devastation from the 2011 event. Nevertheless, 〈http://ieeexplore.ieee.org/document/6107234/〉, 2011 (accessed 07.12.16). as Gyoba [27] found that people outside the damage zone tend to [11] V.Roeber, Tidal Records in Sendai, Miyagi, Japan & observations of the Fukushima-oki tsunami signal, Report on the 2011 Fukushima earthquake and overestimate tsunami heights whereas people within that area tend to tsunami, IRIDeS, Tohoku University. 〈http://irides.tohoku.ac.jp/media/files/ underestimate the heights when receiving tsunami-warning messages. archive/tidal_records_sendai_fukushima-tsunami_2016_roeber.pdf〉, It is therefore necessary to clarify the information for the people to help 2016(accessed 07.12.16). [12] N.Leelawat, A.Suppasri, F.Imamura, Analyzing the essence of the disaster warning them better understand the correct criteria of the warning categories. system in Japan, in: Proceedings of the Second International Education Forum on Further research should be conducted that takes into consideration the Environment and Energy Science, Los Angeles, CA, 2013. response of receivers, especially people outside the affected areas, in [13] T. Ozaki, JMA's tsunami warning for the 2011 Great Tohoku earthquake and – “ ” tsunami warning improvement plan, J. Disaster Res. 7 (sp) (2012) 439 445. order to reduce the cry-wolf syndrome [28]. [14] N.Leelawat, A.Suppasri, M.Yasuda, F.Imamura, Disaster warning broadcasting Another serious issue is people's difficulty in decision-making due process management: A case study of landslide from Typhoon Wipha at Izu- to controversial evacuation suggestions. In 2011, the local authorities Oshima in 2013, in: Report of Tsunami Engineering: Vol. 31, Tohoku University, Miyagi, 2014, pp. 49–57. (e.g., village, town, or municipal administrative levels) within the same [15] A. Suppasri, P. Latcharote, J.D. Bricker, N. Leelawat, A. Hayashi, K. Yamashita, prefecture were responsible to provide evacuation information to their F. Makinoshima, V. Roeber, F. Imamura, Improvement of tsunami counter- residents. As a result, some individuals who moved from a town or city measures based on lessons from the 2011 Great East Japan earthquake and Tsunami – situation after five years, Coast. Eng. J. 58 (4) (2016) 1640011 http:// to another during that period were confronted with various announce- www.worldscientific.com/doi/abs/10.1142/S0578563416400118. ments [29]. This issue raised attention towards revising the evacuation [16] Japan Meteorological Agency (JMA), Criteria for Issuance of Emergency Warnings. guideline in the future. 〈http://www.jma.go.jp/jma/en/Emergency_Warning/criteria.html〉, Lastly, tsunamis are one of the most dangerous natural hazards 2013(accessed 01.09.13). [17] FNN news, Shindo 5- in Fukushima, tsunami observation of 1.4 m, the largest after which can cause harm to people and properties. Traveling to expected the Great East Japan earthquake (in Japanese). 〈http://www.fnn-news.com/news/ tsunami arrival areas with the intent to record videos and take headlines/articles/CONN00342558.html〉, 2016 (accessed 23.11.16). photographs, presents numerous risks to people's safety. We thus [18] A. Suppasri, S. Koshimura, K. Imai, E. Mas, H. Gokon, A. Muhari, F. Imamura, Damage characteristic and field survey of the 2011 Great East Japan tsunami in advise people to go to their designated evacuation shelter and/or stay Miyagi prefecture, Coast. Eng. J. 54 (1) (2012) 1250005 http://www. off the affected area. It is also recommended to limit outdoor and worldscientific.com/doi/abs/10.1142/S0578563412500052. communication activities to the minimum so that the local infrastruc- [19] MGR Online, Japanese government improved the earthquake warning system (in Thai). 〈http://www.manager.co.th/asp-bin/viewgallery.aspx? ture and telecommunication systems can be used for emergency Newsid=9590000116988 & imageid=4325324〉, 2016 (accessed 06.12.16). response. [20] ABC, Japan earthquake: Tsunami warning downgraded after powerful quake off Fukushima. 〈http://www.abc.net.au/news/2016-11-22/japan-tsunami-warning- after-quake-strikes-off-fukushima/8044766〉, 2016 (accessed 12.12.16). Acknowledgments [21] NHK, Breaking News Tsunami Reaches Fukushima, 2016 (accessed 22.11.16). [22] Cabinet Public Relations Office, Cabinet Secretariat, Press Conference by Prime We would like to thank Miyagi Prefecture Fisheries Cooperative Minister Shinzo Abe Following His Visit to Argentina and His Attendance at the

329 A. Suppasri et al. International Journal of Disaster Risk Reduction 21 (2017) 323–330

APEC Economic Leaders' Meeting in Lima, Peru and Related Meetings. 〈http:// [26] N. Leelawat, A. Suppasri, S. Kure, C.J. Yi, C.M.R. Mateo, F. Imamura, Disaster japan.kantei.go.jp/97_abe/statement/201611/1220102_11019.html〉, 2016 warning system in the Philippines through enterprise engineering perspective: a (accessed 12.12.16). study on the 2013 super Typhoon Haiyan, J. Disaster Res. 10 (6) (2015) [23] Facebook, Facebook Safety Check The Earthquake in Fukushima Prefecture. 1041–1050. 〈https://www.facebook.com/safetycheck/fukushima-prefecture-earthquake- [27] E. Gyoba, Differences in subjective estimation of risks and assessment for the nov22-2016/〉, 2016 (accessed 12.12.16). modified tsunami warning system by the Japan Meteorological Agency among [24] United Nations International Strategy for Disaster Reduction (UNISDR), Sendai university students located in damaged and non-damaged prefectures around the Framework for Disaster Risk Reduction 2015–2030, UNISDR, Geneva, 2015. period of the 2011 off Pacific coast of Tohoku earthquake, J. Disaster Res. 9 (4) [25] N. Leelawat, A. Suppasri, F. Imamura, The tsunami warning system in Thailand: a (2014) 571–578. part of the reconstruction process after the 2004 Indian Ocean Tsunami, in: [28] J.H. Sorensen, Hazard warning systems: Review of 20 years of progress, Nat. Vicente Santiago-Fandiño, Yevgeny A. Kontar, Yoshiyuki Kaneda (Eds.), Advances Hazards Rev. 1 (2) (2000) 119–125. in Natural and Technological Hazards Research: Vol. 44. Post-Tsunami Hazard: [29] NHK, One Month After the Tsunami Research Meeting (in Japanese). 〈http:// Reconstruction and Restoration, Springer International Publishing, Cham, 2015, www3..or.jp/tohoku-news/20161222/5053201.html〉, 2016 (accessed 28.12. pp. 111–119. 16).

330