Earthquake Early Warning (Japan)

The Earthquake Early Warning ( EEW ) ( 緊急地震速報Kinkyū jishin Sokuho ) is a warning Issued When an earthquake in Japan is detected. [2] The warnings are Issued Mainly by the Japan Meteorological Agency (JMA), along with guidance is how to react to the warnings. [3] [4]


The JMA has two Earthquake Early Warning schemes. One is for the National Meteorological and Hydrological Services [8] and the other is for the general public. [9] When there is a P-wave detection from any two or more of the 4,235 Seismometers installed Throughout Japan, the JMA automatically analyzes and Predicts the rough area of the earthquake’s epicenter . These rough predictions allow the JMA to warn people in affected prefectures through TV and radio if strong shaking is expected. [9]

An Earthquake Early Warning alert (緊急地震速報(警報)) is Issued To the general public When an earthquake of Japan seismic scale “5-lower” Higher gold is expected. [10] An Earthquake Early Warning forecast (緊急地震速報(予報)) is Issued To the National Meteorological and Hydrological Services When an earthquake of Japan seismic scale 3 or higher, gold magnitude 3.5 or more is expected, Or When a measurement of more Than a 100 gals is detected in the amplitude of P-wave or S-wave . [10]

The Earthquake Early Warning is set to help people in minimizing damages caused by an earthquake: people may take shelter or move away from dangerous areas such as cliffs. Railway workers use this warning to slow down trains and factory workers May use it to stop assembly lines before the shaking Reaches em. [2]

The effectiveness of a warning depends on the position of the receiver. After receiving a warning, a person may have a few minutes to take action. Areas near the epicenter may experience strong tremors before any warning. [11]

After the 2011 Tōhoku earthquake and tsunami , the early warning system, along with Japan’s tsunami warning system , was considered to be effective. Although the tsunami killed over 10,000 people, many more people would have lost their lives without the early warning system. [12]

In April 2011, the Chilean Subsecretary of Telecommunications disclosed that they also hope to establish a similar earthquake early warning system. [13]

Hit rate

The JMA annoncé the hit rate of the Earthquake Early Warning for the 2011 fiscal year is 31 May 2012. The hit rate is defined as the percentage occurrence of the warning Issued time immediately upon P-waves detected Having a Japan Meteorological Agency seismic intensity scale ( 震度shindo ) number (range 0 to 7) That falls Within plus-minus 1 Magnitude-Shindo Number of ten-Magnitude Numbers Shindo Measured for That earthquake. [14]

  • Fiscal year 2007: 75%
  • Fiscal year 2008: 82%
  • Fiscal year 2009: 76%
  • Fiscal year 2010: 28%
  • Fiscal year 2011: 56%

For the fiscal years 2007 to 2009 the hit rate was over 75%. In fiscal year 2010, the hit rate cam down to 28% due to the number of Aftershocks Following the 2011 Tōhoku earthquake and tsunami , qui occurred near the end of fiscal year 2010. The hit rate for That HAD beens year 72% up to the Tohoku earthquake. Measurement techniques have subsequently been refined to ignore small scale earthquakes; The hit rate for fiscal year 2011 increased to 56%. The JMA is expected to increase 85% in fiscal year 2015.

Format of EEW broadcasts


It NHK television channels and other Japanese TV broadcasters ( ISDB Including 1seg ), [15] HAS year alert That Consists of a Message That window flashes on the screen showing the earthquake epicenter and the areas affected by strong tremors. At the same time, two sets of chimes sound, after which a voice announces in Japanese:

“This is an Earthquake Early Warning. Please prepare for powerful tremors.” ( 「緊急地震速報です.強い揺れに警戒して下さい.」Kinkyū jishin Sokuho desu. Tsuyoi yure or keikai shite kudasai. )

The announcement Above is used by the NHK, Fuji TV , TV Asahi and Tokyo MX , whilst Nippon TV and TBS simply shorten it to “Kinkyū jishin Sokuho desu.” TV Tokyo sound a set of chimes, but do not use a voice announcement.

These alerts also inform us whether or not there is a risk of a landslide or tsunami caused by the quake in the affected area. If tsunami warnings are issued, the system utilizes 1seg to automatically turn on (and tune to NHK) all radios and televisions with 1seg technology in the areas at risk. All warnings are broadcast in five languages: English, Mandarin, Korean and Portuguese, as well as Japanese. [16]

Mobile phone networks

Japan’s three major mobile phone carriers, NTT docomo , at ( KDDI and Okinawa Cellular) and SoftBank Mobile , Developed-have simultaneous broadcast to multiple systems allow users recevoir year SMS telling of the EEW ( ‘ Cell Broadcast ‘). [17] [18] [19]

(Nokia, Apple, HTC, LG, Samsung, etc.) are not covered. In August 2011, Apple announced that its iOS 5 iPhone will support early warning notification. [20]

NTT docomo

EEW is enabled by default are all models of the FOMA 905i series ( FOMA 905iシリーズ ) released on 26 November 2007, some FOMA High-Speed models of the FOMA 705i series ( FOMA 705iシリーズ ) released in February 2008. [21] [22 ]


EEW is enabled are all models from early 2008. Including W61CA , W61H , W61K , W61SA , W61SH , W62SA and A Few smartphone models, Such As IS02 (TSI01). KDDI and Okinawa Cellular started EEW broadcast via at’s Short Message Service called Expired C-mail ( ja: Cメール ) for free on 25 March 2008. [23]

SoftBank Mobile

On 30 May 2007, SoftBank announced development of an EEW broadcast system similar to those of NTT docomo and au. [24] Deployment of this system was originally planned in the fiscal year 2008 but postponed for two years. On August 25, 2010, EEW service began in all areas of the Kansai region , Tokai region , Tohoku region (seven prefectures), Chugoku region , and Shikoku region as well as areas of the Kanto region . The EEW broadcast network covers the whole country since 7 December 2010. As of March 2011, ja: SoftBank 831N is the only model that supports EEW, although more models are expected to support EEW after summer 2010.


RC Solution iPhone application named “Yurekuru Call for iPhone” to receive EEW, which is distributed on the Apple App Store for free; The application is now available for Android. Notification of an EEW could be delayed or blocked if communication lines are congested. [25] [26] The Japan-localized version of iOS 5 for iPhone has built-in EEW functionality.

Radio receivers

FM radio type, Iris OhyamaModel: EQA-001, front view (upper), rear view (Lower)

The specific and common chime tone from FM stations is automatically detected internally and turns on the radio (if in sleep mode ) and loudly sounds a chime tone and EEW messages before shaking OCCURS by S-wave . Once the S-wave has been analyzed, detailed information on the earthquake, such as its seismic scale and the areas under threat, is announced.

  • Iris Ohyama EQA-001 [27]
  • Iris Ohyama EQA-101 [28]
  • Uniden EWR200 [29] supports EEW and the Emergency Warning System ( ja: 緊急 警報 放送 Kinkyū Keihō Hōsō )
  • P2PQuake ( ja: P2P 地震 情報 P2P Jishin Jōhō ) recognizes voices on NHK Radio 1 .

These receivers utilize EEW broadcast from radio stations and are free of specific information fees or connection fees. EEW radio waves can be received even in areas where no broadband Internet access is available. The quality of service, rapidity, and service area vary from station to station.

Radio Stations with the EEW System

  • NHK Radio 1 and Radio 2 , Nationwide
  • JOGV-FM (bayfm78) , Chiba [30]
  • JOAU-FM (Tokyo FM) , Tokyo [31]
  • JOAV-FM (J-Wave) , Tokyo [32]

Cable television

A rental EEW receiver of JCN Funabashi – Narashino

Japanese cable TV stations offer affordable EEW services. For example, Japan Cablenet ( ja:ジャパンケーブルネット) (JCN) rents out a receiver That Receives EEW for advanced users and notified the user of the Estimated Shindo scale and the remaining time (0 to 5 seconds). [33] [34] Some cable TV stations also broadcast EEW on community radio FM and provide equipment to prefectural and municipal facilities for free.


Weathernews Inc. ( ja:ウェザーニューズ ) , has weather information company, started a paid Service to broadcast EEW for advanced users, The Last 10-Second , used by people and businesses is 15 October 2007. [35] [36] [37] This service requires a computer running Windows 2000 or later with an affordable alternative used for exclusively for EEW. The EEW application installed on the computer can be configured to receive information on all earthquakes with a JMA magnitude of 3.5 or higher or with a seismic intensity of 3 or higher. Newer versions of the program allow for the announcement of lower-intensity earthquakes. When an EEW warning is issued,

On 7 July 2008, ANET CO., LTD. ( Ja: ANETアネット ) , a disaster prevention technology company of the Railway Technical Research Institute Group, released an application EQMessenger, recevoir ANET Alert, qui ciphers and broadcasts EEW information on the epicenter, the Estimated seismic intensity at the user’s location, And the remaining time before the arrival of the S-wave. [38] When the Estimated seismic intensity Exceeds the preset level, EQMessenger can sound a warning and display the epicenter, the intensity estimation point and the arrival of the tremor was pop-up map.

After the 2011 Tōhoku earthquake , a similar Windows program was made available for free by the Strategy Corporation ( ja: ス ト ラ テ ジ ー 株式会社 ) called SignalNow Express. [39]

Identification of EEW capable devices

The current Earthquake Early Warning logo used by the Japan Meteorological Agency uses a yellow catfish known as a Namazu ( 鯰 ) . Many earthquake preparedness activities in Japan use the catfish have a mascot, as Japanese lore suggéré earthquakes That Were Caused by a giant catfish making tremors, gold que la sight of catfish Foretold of earthquakes. [40]

See also

  • Earthquake warning system
  • Earthquake prediction
  • J-Alert
  • Cell Broadcast
  • Specific Area Message Encoding
  • Weatheradio
  • ShakeAlert


  1. Jump up^ “Earthquakes and Tsunamis – Disaster prevention and mitigation efforts”(PDF) . Retrieved 16 April 2016 .
  2. ^ Jump up to:b “What is the Earthquake Early Warning (or” 緊急 地震 速 報 (Kinkyu Jishin Sokuho) “in Japanese)?” . Japan Meteorological Agency . 2007-08-30 . Retrieved 2008-06-29 . External link in ( help ) |publisher=
  3. Jump up^ “Earthquake Early Warning Starting 1 October 2007” (PDF) . Japan Meteorological Agency. 2007-08-30 . Retrieved 2008-06-29 .
  4. Jump up^ “How to respond to earthquake early warnings” (in Japanese). NHK(Japan Broadcasting Corporation) . Retrieved 2009-05-09 .
  5. Jump up^ giving guidelines
  6. Jump up^ Sankei-MSN News (2011-05-01 9:55 p.m.) “The Earthquake Early Warning – the chime contained the tone of breads, Even Examined the ‘Godzilla” affairs / news / 110501 / dst11050121570027-n1.htm
  7. Jump up^ guidelines for use
  8. Jump up^
  9. ^ Jump up to:b 緊急 地震 速 報 に つ い て | 緊急 地震 速 報 の 内容(In Japanese). Japan Meteorological Agency . Retrieved 2008-06-29 .
  10. ^ Jump up to:b 緊急 地震 速 報 の し く み と 予 報 · 警報[About EEW alert and forecast] (in Japanese). Tokyo: JMA . Retrieved 2011-04-14 .
  11. Jump up^ 緊急 地震 速 報 と は(In Japanese). Japan Meteorological Agency . Retrieved 2008-06-29 .
  12. Jump up^ Amitabh Sinha (2011-03-12). “Early warning system saved Japan worst of tsunami wrath” . Indian Express .
  13. Jump up^ “The Japanese earthquake pushed ISDB-T alert system in Chile” . NexTV Latam, TV Telco Latam. 2011-04-01 . Retrieved 2011-04-09 .
  14. Jump up^ 平 成 24 年 報道 発 表 資料[Fiscal year 2012 (Heisei 24) press release, Material No.2 FY 2011 (Heisei 23) Task review report ] (PDF) (in Japanese). Tokyo: JMA . 2012-05-31. p. 25/147 sheet, page 2-15 . Retrieved 2012-06-03 .
  15. Jump up^ 8 Japanese Channels broadcasting the EEW simultaneously.
  16. Jump up^ Tsunami Warning in multiple languages.
  17. Jump up^ 緊急地震速報に対応し(NTT docomo press release 30 May 2007)
  18. Jump up^ 緊急地震速報に対応し(KDDI news release May 30, 2007)
  19. Jump up^ 「緊急地震速報」について(SoftBank Mobile press release 30 May 2007)
  20. Jump up^
  21. Jump up^ CEATECド コ モ 90 90 90 90 に に に </s> </s> (Nikkei ITPro 2 October 2007)
  22. Jump up^ 緊急 速 速 「」 」」 」」
  23. Jump up^ 緊急地震速報の提供開始に KDDI Corporation
  24. Jump up^ 「緊急地震速報」について SoftBank
  25. Jump up^ ゆれくるコール”for iPhoneサポートサイトRC Solution Co.
  26. Jump up^ あと何秒で地震が来iPhoneアプリに惚れた!Weekly ASCII PLUS, 30 November 2010
  27. Jump up^ Ohyama
  28. Jump up^ Ohyama
  29. Jump up^
  30. Jump up^ Bay FM’s Earthquake Early Warning
  31. Jump up^ Tokyo FM’s Earthquake Early Warning
  32. Jump up^ J-Wave’s Earthquake Early Warning
  33. Jump up^ 事例報告:地震の揺れが到達するKabushiki-gaisha JCN-Funabashi Narashino
  34. Jump up^ 事例報告:地震の揺れが到達する!Kabushiki-gaisha Kamakura Cable Communications
  35. Jump up^ 個人向け緊急地震速報サ「The Last 10-Second」 10月15日から開始(Weathernews Inc. press release 27 September 2007)
  36. Jump up^ 個人向け緊急地震速報サ「The Last 10-Second」Weathernews Inc.
  37. Jump up^ 事業者向け緊急地震速報「The Last 10-Second」Weathernews Inc.
  38. Jump up^ 株式会社ANETが緊急地震速報受信ソEQMessenger:イーキューメッセ)の発売を開始ANET Co., Ltd.
  39. Jump up^
  40. Jump up^ [1]

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