apanese Nationwide Earthquake and Tsunami Observation Network Operated by NIED

Transcription

1 APEC Workshop on Application of Big Data and Open Garden Hotel (2015/10/29-30) apanese Nationwide Earthquake and Tsunami Observation Network Operated by NIED Shin Aoi National Research Institute for Earth Science and Disaster Prevention

2 Impact of the 1995 Kobe Earthquake Research for Earthquake Prediction (1960 s~) The Kobe (Hyogoken-Nanbu) Earthquake (Mw 6.9) attacked the metropolitan area in western Japan on 17 January More than 6,000 people were killed by this earthquake. Special Measure Law on Earthquake Disaster Prevention was enacted and The Headquarters of Earthquake Research Promotion was established to promote earthquake research with the goal of the reduction of damage and casualties from earthquakes. Fundamental surveys and observation for earthquake researches started as a governmental policy. 2

3 Seismograph Network Operated by NIED (Inland) As a part of Fundamental surveys and observation for earthquake researches,, NIED takes a responsibility for earthquake observation. Purposes: Earthquake mitigation and understanding of earthquake phenomenon. - Long term evaluation of earthquake occurrence. - Evaluation of current crustal activity - Ground motion and tsunami hazard evaluation - Early transmission of earthquake information. Open data: All the data is open to the public and can be free access from the Internet. High sensitivity seismograph network (Hi-net) Spacing of ~20 km (800 stations) Purpose - Improvement of detection capability for microearthquakes. - Evaluation of depth of a seismogenic layer in upper crust. Broadband seismograph network (F-net) Spacing of 100 km (73 stations) Purpose - Construction of moment tensor solution catalog. - Evaluation of source process for large earthquakes. Strong motion seismograph network (K-NET&KiK-net) Spacing of 20 km ( stations) Purpose - Measurement of strong ground motion. - Evaluation of source process for large earthquakes. 3

4 S-net:Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench First dense real-time observation network in the ocean (6 segments & 150 observatories) - Total length of the ocean bottom fiber optic cable: 5,700 km. - Covers the wide area of Japan Trench from Kanto to Hokkaido. - At least one observatory in a source region of M7.5 earthquake. - Nodes are planned to install every - 30 km in a direction cross to trench km along direction to the trench Objectives Real time ocean bottom pressure measurements for the nextgeneration tsunami warnings which estimate coastal tsunami heights precisely. Real time ocean bottom seismological measurements for a much earlier JMA Earthquake Information. Investigation of a large earthquake generation process in the vicinity of Japan Trench associated with subducting Pacific plate. Investigation of ocean bottom crustal movements (vertical component). 4 Off Iwate Aomori 3 Off Miyagi Iwate 2 Off Ibaraki Fukushima 1 Off Boso Landing Station DONET1 (in operation) DONET2 is now constructed by JAMSTEC and whose authority will be transfer to NIED. 4

5 Total size of data: 362TB (1996/6 2014/9) (114 GB/day) Total # of events: 2.4M (1996/6 2014/9) (2011:0.3M event) Earthquake catalog of Hi-net Detection ability 5

6 Earthquake Early Warning System operated by JMA 200 JMA stations and 800 NIED Hi-net stations are used. (JMA website) 6

7 EEW: time requires from P-wave arrival 地震数 Nov. 2007~Jul & Imax > 4 Earthquake issued EEW (197 eqs.) Negative lead time area 伝わるまでの時間 ( 秒 ) 震源深さ 20km を仮定速度構造モデルは JMA2001 P 波走時 S 波走時提供まで 3 秒提供まで 5 秒 地震を検知してから第 1 報が提供されるまでの時間 ( 秒 ) 震央距離 (km) Time requires for issue EEW: 3-5 sec. from the arrival of P-wave to the nearest station to the epicenter. Radius of an area of negative lead time is km 7

8 Realtime transmission of continuous data: EarthLAN - EarthLAN: a service constructed on a IP-VPN network. - Continuous data: directly transmitted from each station to NIED & JMA - Data exchange: all the seismological data from the observation network operate by NIED, JMA, universities and other institutes Hi-net / F-net observation station Latency < 1 sec. IP-VPN Network (EarthLAN) NIED TDX Latency < 1 sec. NIED Internet Data archive Provide / Research JMA Universities Monitoring / warning unified eq. catalog EEW local government, JAMSTEC, AIST, etc. Education / Research 8

9 Conceptual diagram of EarthLAN Hi-net Hi-net / / F-net F-net stations 観測点 900 stations all over Japan Data transmission Sending 送信局 ADP ADP STM Data transfer, data re-transmission Data broadcast Temporary data backup (20 days) Status of operation : : EarthLAN IP-VPN Network Archive Transfer AP AP Backup Watching service Control center Receiving ADP Receiving ADP Receiving ADP NIED DMC JMA TDX Low latency path(udp) High reliance path(tcp) 9

10 EarthLAN : Low latency Average latency of data transmission Data: 100Hz continuous data Usually less than 1 second and the average latency is 360 msec. Deterioration of efficiency during earthquake is sight. Delay Time [ms] Change of average delay (every minutes) 17:08 M6.7 Off-Fukushima /03/13 10

11 Kyoshin monitor: Visualization of continuous indexes Strong motion in Japanese Web service which provides a map of the current ground motion of Japan Island. Continuous and immediate transmission KiK net (+ some K NET): Continuous communication Every second, Real time Intensity, PGA, PGV, PGD, Response spectra calculated in situ (inside the instrument). Web server Arranged every sec. NIED DMC in Tsukuba Indexes are arranged every sec. and the GIF files for the map are automatically created and sent to web server. Suzuki et al., 2014, SSJ Internet * New index for long period ground motion. * Easy to apply various indexes. 11

12 API and smartphone app. WebAPI and smartphone application: to provide real time data and related information In mobile environment, data traffic and battery are limited automatic starting (pop up) function triggered by EEW Buttery residual [%] Consumption of electricity for continuous reception EQ GCM (Google Cloud Messaging) Push 通知 手動起動にも対応 ( 防災訓練等への活用 ) API リアルタイム震度 ( 実測地震動 ) 防災訓練などでの活用も可能 緊急地震速報 12

13 Direct detection of huge (8<M) earthquake Physically difficult to quickly know the Magnitude of huge earthquake > underestimation of EEW. Use only observed seismic intensities and count up the numbers of stations where the intensities exceed certain threshold. Histogram: Station numbers vs. intensities M9.0 (2011 Tohoku) M9.0 Anticipated Nankai Tonankai By applying this method successively to real time seismic intensities, the growth process of huge earthquake may watch in real time. Station numbers Seismic intensities Nakamura et al., JpGU, M9.0 Anticipated Nankai Tonankai M9.0 (2011 Tohoku) M8.0 (2003 Tokachi oki) M7.7 (Largest aftershock of 311) 7.0 M 7.4 (N=17) 6.5 M 6.9 (N=35) 13

14 Area early warning method using real-time seismic intensity [Goal] Predict the warning areas whose seismic intensity will exceed threshold using real time information. [Warning areas] Whole Japan is divided into 188 areas. [Algorithm] * When one of the station located in the area observe realtime intensity larger than threshold: the area is deem to be warning area. * When one of the station located in the area observe realtime intensity larger than sub threshold (which is smaller than threshold): the area is assumed to be warning area. * The area adjacent to the threshold exceeded area is also assumed to be warning area. Exceeding Sub threshold OT+67s OT+77s OT+47s OT+102s OT+266s OT+57s OT+152s OT+205s Nakamura et al., SSJ, Tohoku earthquake Adjacent territory Exceeding threshold Sub-threshold and adjacent territory Warning not to use source information :K-NET,KiK-net Rapidity For huge eq., simultaneous eq. 14

15 Real-time system for earthquake damage estimation (J-RISQ) A real time system to estimate numbers of damaged buildings and exposed population in 250 m meshes is estimated. It takes less than one minute for the first estimation and reports are updated several times using all the available data at the moment. K-NET KiK-net Estimated seismic intensity distribution K-NET 1007 KiK-net 689 seismic intensity data JMA&local governments Building damage assessment Estimated exposed population JMA 665 Local governments 2917 Aoi et al., AGU, 2013 J-RISQ report. 15

16 Summary After the 1995 Kobe earthquake, NIED has constructed and operated dense seismograph networks covered with Japan island. After the 2011 Tohoku earthquake, NIED is constructing S-net (Seafloor observation Network for Earthquakes and Tsunamis along the japan trench) that covers wide area of Japan Trench from Kanto to Hokkaido. All these huge data is freely available. Huge amount of real-time data from dense network are expected to directly contribute to the mitigation of ongoing earthquake disasters. - Earthquake Early Warning - Kyoshin monitor - Direct detection of huge earthquake - Area early warning method - Real-time earthquake damage estimation (J-RISQ) Prompt processing of big data is key technology. - data transmission, processing, visualization Sensor network + cloud system 16