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 Pacific Tsunami Warning Center/NOAA Exchange of Information ・ Hypocenter ・ Magnitude ・ Tsunami Observation Seismological Data Sea Level Data Tsunami Warning to Japan Northwest Pacific Tsunami Advisory Tsunami Watch Information to the Indian Ocean Countries JMA Tsunami Warning Service

Occurrence of Earthquake GenerationofTsunami Detection of Seismic Wave Determination of Location and Magnitude Evaluation of Expected Tsunami Issuance of Tsunami Warning Update of Tsunami Information Detection of Tsunami at sea level station Seismic Network Real time data processing system Components of tsunami warning system Sea Level Data to monitor tsunami Sequence of Tsunami Warning Real time data transmission Re-evaluation of Tsunami (Propagation)

Techniques for determination of hypocenter and magnitude of distant earthquakes

Global Seismological Network (IRIS/USGS, IRIS/IDA) Worldwide Network (Broadband Stations) IRIS/USGS seismic data via the Internet.

Analyzing the Location of the Earthquake

Comparison with Epicenters (USGS) USGSJMA

Calculation of Mwp Seismic wave form of UD component of STS2 seismometer Frequency response of the filter applied to the seismic wave data S S P P

Empirical formula for Mwp 3minutes P-S

Comparison with Mw(Harvard)

Major Tsunami Tsunami Tsunami Attention Tsunami Forecast Operation Issuance of tsunami warning which contains forecasted arrival time and tsunami height in each coastal region (66 regions in Japan) Tsunami Database Tsunami Warning Retrieve from the database of tsunami height referring to the location and magnitude of the earthquake Numerical Simulation

Setting Fault Models Assumed Epicenter: Magnitude ： 7.0, 7.5, 8.0, , 7.5, 8.0, 8.5 Depth ： 0, 20, 40,60,80,100km

CMT analysis Length of Data –20 minutes –30 minutes YAK ULN KONO MA2 Comparison between synthetic waves(red) and observed waves(blue). Radial, transverse and vertical component from top and bottom in each station.

JMA Harvard Centroid Moment Tensor Solution

Northwest Pacific Tsunami Advisory

Global Seismic Network Northwest Pacific Tsunami Advisory Center Estimated Tsunami Arrival Time and Height Countries in Northwestern Pacific Ocean JMA Headquarters Japanese Seismic Network Pacific Tsunami Warning Center (PTWC) Information Exchange - Magnitude - Epicenter - Tsunami Information

Contents of Northwest Pacific Tsunami Advisory Responsible Coasts of NWPTAC 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

Sea Level Stations in the Pacific Ocean

Interim Provision of Tsunami Watch Information for the Indian Ocean

Motivation for Interim Provision of Tsunami Watch Information for the Indian Ocean Country Interim Provision of Tsunami Watch Information Need an Emergency Measure If a big tsunami were generated again

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 Sea level data Japan Meteorological Agency Collection via Internet Country Dissemination of Tsunami Watch Information Pacific Tsunami Warning Center Collection via Internet or Meteorological Satellites Seismic waveform data Country Through the Global Telecommunication System of WMO, and/or Facsimile (Currently available) (Enhancement of communication facility of existing tide gauges) National arrangements Indian Ocean region on the responsibility and initiative of the individual countries!

India Indonesia Australia Malaysia Thailand Myanmar Bangladesh Iran Pakistan Oman Yemen UAE Sri Lanka Maldives Singapore Mozambique East Timor Seychelles South Africa Tanzania Kenya Reunion Island Chagos Archipelago Mayotte Island Kerguren Island Amsterdam Island St. Paul Island Mauritius Madagascar Comoros Crozet Island Recipient Countries

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 Contents of TWI

Sea Level Stations in the Indian Ocean

Colombo Male Hanimaadhoo Gan Port Louise Port La Rue Salalah Sea level data （ Indian Ocean ） 1m Sea Level Data of M8.7 Sumatra Earthquake on 28 March in the Indian Ocean 3/29 3/30 JST

The Northwest Pacific Tsunami Advisory and the Tsunami Watch Information Issued since March 2005

Elapsed Time until Issuance

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