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Tsunami Advisory Information for the Northwest Pacific and Indian Oceans issued by the Japan Meteorological Agency. Yuji NISHIMAE Japan Meteorological Agency. Contents. JMA Tsunami Warning Service Techniques for determination of hypocenter and magnitude of distant earthquakes
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Tsunami Advisory Information for the Northwest Pacific and Indian Oceans issued by the Japan Meteorological Agency Yuji NISHIMAE Japan Meteorological Agency
Contents • JMA Tsunami Warning Service • Techniques for determination of hypocenter and magnitude of distant earthquakes • Northwest Pacific Tsunami Advisory • Tsunami Watch Information for the Indian Ocean • Summary
JMA Tsunami Warning Service Tsunami Warning to Japan Seismological Data JMA Northwest Pacific Tsunami Advisory Sea Level Data Tsunami Watch Information to the Indian Ocean Countries Exchange of Information ・Hypocenter ・Magnitude ・Tsunami Observation Pacific Tsunami Warning Center/NOAA
Sequence of Tsunami Warning Occurrence of Earthquake Generation of Tsunami Components of tsunami warning system Detection of Seismic Wave Seismic Network Real time data transmission Determination of Location and Magnitude (Propagation) Real time data processing system Evaluation of Expected Tsunami Detection of Tsunami at sea level station Issuance of Tsunami Warning Sea Level Data to monitor tsunami Update of Tsunami Information Re-evaluation of Tsunami
Techniques for determination of hypocenter and magnitude of distant earthquakes
Global Seismological Network (IRIS/USGS, IRIS/IDA) WorldwideNetwork(Broadband Stations) IRIS/USGS seismic data via the Internet.
Comparison with Epicenters (USGS) USGS JMA
S P S P Calculation of Mwp Frequency response of the filter applied to the seismic wave data Seismic wave form of UD component of STS2 seismometer
Empirical formula for Mwp 3minutes P-S
Tsunami Forecast Operation Numerical Simulation Tsunami Warning Retrieve from the database of tsunami height referring to the location and magnitude of the earthquake Major Tsunami Tsunami Tsunami Attention Issuance of tsunami warning which contains forecasted arrival time and tsunami height in each coastal region (66 regions in Japan) Tsunami Database
Assumed Epicenter: 41 Magnitude: 7.0, 7.5, 8.0, 8.5 Depth : 0, 20, 40,60,80,100km Setting Fault Models
CMT analysis YAK ULN • Length of Data • 20 minutes • 30 minutes MA2 KONO Comparison between synthetic waves(red) and observed waves(blue). Radial, transverse and vertical component from top and bottom in each station.
Centroid Moment Tensor Solution JMA Harvard
Northwest Pacific Tsunami Advisory Center JMA Headquarters Japanese Seismic Network Estimated Tsunami Arrival Time and Height Global Seismic Network Countries in Northwestern Pacific Ocean Information Exchange - Magnitude - Epicenter - Tsunami Information Pacific Tsunami Warning Center (PTWC)
Contents of Northwest Pacific Tsunami Advisory • Source Parameters • Origin time (UTC), Coordinates (latitude, longitude), Location name of the epicenter , Depth (if 100km or more), magnitude • Evaluation of Tsunamigenic Potential • Estimated heights and arrival times • Observations of tsunami Responsible Coasts of NWPTAC
Interim Provision of Tsunami Watch Information for the Indian Ocean
Motivation for Interim Provision of Tsunami Watch Information for the Indian Ocean Country If a big tsunami were generated again Need an Emergency Measure Interim Provision of Tsunami Watch Information
Tsunami Watch Information should be Regarded as a Reference for Taking Preventive Measure against Possible Tsunamis on the Responsibility and Initiative of the Individual Countries Indian Ocean region (Currently available) Japan Meteorological Agency Seismic waveform data Country Seismic waveform data Collection via Internet Dissemination of Tsunami Watch Information Country (Enhancement of communication facility of existing tide gauges) Country Sea level data Sea level data Pacific Tsunami Warning Center Through the Global Telecommunication System of WMO, E-mail and/or Facsimile Collection via Internet or Meteorological Satellites National arrangements • on the responsibility and initiative • of the individual countries!
Recipient Countries Iran Pakistan Bangladesh UAE India Myanmar Oman Thailand Yemen Sri Lanka Malaysia Maldives Kenya Singapore Seychelles Chagos Archipelago Tanzania Indonesia Comoros East Timor Mayotte Island Madagascar Mozambique Mauritius Reunion Island Australia South Africa Amsterdam Island St. Paul Island Kerguren Island Crozet Island
Contents of TWI • Source Parameters • Origin time (UTC), Coordinates (latitude, longitude), Location name of the epicenter , Depth (if 100km or more), magnitude • Evaluation of Tsunamigenic Potential • Estimated Tsunami Travel Time • Observations of tsunami
Sea Level Data of M8.7 Sumatra Earthquake on 28 March in the Indian Ocean Sea level data (Indian Ocean) 1m Colombo Male Hanimaadhoo Gan Port Louise Port La Rue Salalah 3/29 3/30JST
The Northwest Pacific Tsunami Advisory and the Tsunami Watch InformationIssued since March 2005
SUMMARY • NWPTA:2times, TWI: 7 times since March • Issuance within 30 minutes • No significant difference between JMA and USGS, Harvard in location and magnitude • Improvement of accuracy of depth of an earthquake