TWC Operations Challenges and Limitations

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1 UNESCO IOC CTIC US NOAA ITIC Regional Training Workshop on Strengthening Tsunami Warning and Emergency Response Standard Operating Procedures and the Development of the ICG/CARIBE-EWS PTWC New Enhanced Products 1-5 April 2014, Mexico City, Mexico TWC Operations Challenges and Limitations Laura Kong UNESCO/IOC NOAA International Tsunami Information Center Charles McCreery Pacific Tsunami Warning Center

2 An Example of the Simulation for Tonankai Earthquake in 1944

3 (Simulation) Japan Trench and Chishima Tranch EQ Honsyu 20m Hokkaido Tsunami Height Estimation (Tsunamis by the EQs in the vicinity of Japan Trench and Chishima Trench) 15m (The latest simulation by the Central Disaster Management Council) 52

4 General Categories of TWC Activities Seismic Analysis Rapid Recognition of Potential Tsunami Rapid Characterization of Tsunami Source Sea Level Data Analysis Detect/Confirm Tsunami Waves Refine Tsunami Source Tsunami Forecasting Predict Tsunami Hazard Where?, How Big? Message Creation and Dissemination Alert and Motivate End-to-End to Save Lives

5 Tsunami Forecast Operation for Tsunamis from nearby Origin JMA Seismic Network Tidal Network Tsunami Warning オホーツク海沿岸北海道日本海沿岸北部 Evaluation of Tsunami 北海道日本海沿岸南部 北海道太平洋沿岸西部 青森県日本海沿岸陸奥湾 北海道太平洋沿岸中部 青森県太平洋沿岸 北海道太平洋沿岸東部 岩手県 Major Tsunami Tsunami 8m 以上 Tsunami Attention 8m~2m 8m 以上 4m~2m 2m~1m 1m 以下 宮城県 8m~2m 4m~2m 2m~1m 1m 以下 データベース Tsunami Forecast Database 8m 以上 8m~2m 4m~2m 2m~1m 1m 以下 Quantitative Tsunami forecast (arrival time and Tsunami height) Tsunami warning for 66 regions

6 What we need for Tsunami Warning Generation of Tsunami Occurrence of Earthquake Detection of Seismic Wave of Magnitude and Hypocenter Components of tsunami warning system Network of seismographs Real time data transmission Real time data processing system Evaluation of Tsunami Criteria for Tsunami grade Detection of Tsunami Re-evaluation of Tsunami threat Issuance of Tsunami Warning Issuance of Tsunami Information Communication facility to disseminate Tsunami Warning Network of tide gauge to monitor tsunami

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12 IRIS Focal mechanism & Seismic moment atch?v=momvokyddlo atch?v=hl3kgk5eqaw

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14 Limitations of Seismic Analysis Speed of Initial Analysis Depends On Density of Seismic Network Type and Quality of Seismic Stations Speed of Data Transmission Speed of Seismic Processing Confidence in Result Elapsed Time to Initial EQ Parameters 5-10 min with Regional Network min with Global Network

15 Limitations of Seismic Analysis Accuracy of Hypocenter (Location / Depth) Bias - nearby stations only on one side Latitude, Longitude error not so critical But depth critical to tsunamigenesis Depth constraint poor (especially if shallow) Hypocenter is only the point of initial rupture Tsunamigenic earthquakes have large source

16 Limitations of Seismic Analysis Accuracy of Earthquake Magnitude Rapid methods underestimate great events Magnitude is a very limited representation of earthquake size No magic threshold for tsunamigenesis

17 Limitations of Seismic Analysis Anomalous Events Slow earthquakes Traditional magnitudes underestimate Enhanced tsunami potential Landslide tsunamis Smaller earthquake triggers landslide Landslide generates tsunami 1998 Papua New Guinea, Mw=7, >2000 casualties Splay faults Splay fault rupture accompanies main rupture Tsunami generated closer to shore

18 Splay Fault

19 September 1992 Nicaragua Tsunami Ms=7 earthquake off the coast of Nicaragua Very little shaking along the coast Little or no tsunami expected, but Large tsunami struck 116 lives lost Lessons Learned Slow Earthquake Use Mw, not Ms Not always shaking

20 Slow Earthquake: 2006 Java Tsunami Little apparent ground motion Large surf, so no clues in ocean behavior Death toll 730

21 Tsunami Earthquake Aleutian Mt: M estimated by observed tsunami heights Sanriku Tanioka 1996

22 New Guinea Tsunami - Jul 1998 Mw 7.1 earthquake no tsunami expected, but Large tsunami impact 2200 lives lost Probable cause was undersea landslide triggered by the earthquake Lessons Learned Tsunami possibility after any large earthquake Roar from the sea may be only real warning

23 Sumatra Tsunami - Dec 2004 Mw 9.2 earthquake size not known for 4 hours Rupture direction and extent only known later Unrecognized hazard nothing like this expected End-to-end alerting not possible Lessons Learned Use new methods to measure huge quakes Techniques to quickly gauge rupture area Expect 1000-yr event Use forecast models End-to-end alerts

24 Japan Tsunami Mar 2011 Mw 9.0 earthquake that big was not expected First alert in 3 min, but earthquake size and forecast tsunami impacts too small Human behavior some did not evacuate Lessons Learned Expect 1000-yr event Conservative first alert message Study/address how to motivate right actions

25 What to do. Prepare in advance. Have SOPs for your organisation Have SOPS across organisations Test SOPs against scenarios and across organisations Have good relationships with key people in all response organisations Know who needs fast notification Know who to call for help (scale up) Have a variety of sources for information Bookmark those sources

26 In Conclusion Every tsunami is unique and can provide new information to improve early warning The problem is dynamic technologies for detection, evaluation, forecasting, and alerting keep changing Coastal vulnerabilities change with increasing coastal populations and infrastructure Human behavior and how to affect it keeps changing (e.g., social media) We must continue to share our knowledge and experiences to improve the system.

27 Complementary Note Tsunami may arrive before residents receive tsunami warnings Share Understanding of the Limitation of Tsunami Forecast Technique and NOT Rely Only on Tsunami Warnings Build Up Public Awareness When a strong shake is felt, leave the seashore immediately and take shelter to the place of safety even if a tsunami warning is not issued

28 Thank You Masahiro Yamamoto UNESCO/IOC Laura Kong UNESCO/IOC NOAA International Tsunami Information Center Charles McCreery Pacific Tsunami Warning Center

29 Tsunami Travel Times from Small/Large Source

30 Limitations of Tsunami Forecasting Estimated Arrival Time Forecast Based on initial seismic analysis Point source or assumed finite fault Initial Threat Level Forecast Based only on initial seismic analysis Least accurate Sea Level Constrained Forecast Too late for local tsunami Deep ocean measurements best constraint More accurate

31 Limitations and Challenges Real-time forecasting is of limited use for local warning. Self-evacuation might be the only way to avoid the loss of lives. Real-time forecast is only the EQ parameters. Initial EQ mag off by 0.2 or more, resulting in factor of two difference in wave amplitude. Landslide model (currently simply slump model) Asteroid Tsunami Meteorological tsunamis

32 Limitations of Tsunami Forecasting Historical Comparisons Historical record is very short and incomplete in most areas No repeat events May be okay to identify coastal sensitivities

33 Limitations of Messages / Dissemination Message Content Should be simple and to the point Should contain key information Situation Evaluation and Summary Seismic Parameters Predicted Threat Level Estimated Tsunami Wave Arrival Times Key Tsunami Wave Measurements Recommended Actions Tied to SOPs and trigger SOP actions

34 What You Can Count On from a TWC Rapid Notification of a Potential Tsunami Threat Conservative Evaluation of Tsunami Threat Reasonably Rapid Stand-Down if No Tsunami Threat

35 What You Should Be Prepared For Over-Warning due to Conservative Criteria General Forecast of Threat with Few Specifics Potential for Error in ETAs

36 Limitations of Sea Level Data Analysis Sea Level Measurements are Critical for: Tsunami Detection (Yes or No) Tsunami Measurement (Arrival Time, Amplitude, Period, Duration) Tsunami Forecast

37 Limitations of Sea Level Data Analysis Speed of Sea Level Measurements Tsunami must travel to gauge Depends upon density of gauge network 15 min to >1 hr typical to first gauge Tsunami wave must pass gauge Wave periods are 5 to 60 min Need at least ¼ of wave Tsunami is a series of waves Maximum may not be first wave Gauge must transmit data Typically every 15 min

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43 Limitations of Sea Level Data Analysis Type of Sea Level Measurements Coastal Gauge Most common Signal highly modified by coastal effects May be destroyed by large tsunami Deep Ocean Gauge Less common Most expensive Pure tsunami signal to constrain forecast Wet Sensor On land Less expensive Only indicate if flooding has occurred

44 Tsunami Monitoring Estimate tsunami travel time Continuous monitoring: tide gauge, deep sea pressure; in case M:6 class Monitor: all sea level stations NOT only your stations Re-evaluation using observed data Upgrading/Downgrading/Cancellation of tsunami warning

45 Taking Action What to do Timely Warnings from TWC How? Careful monitoring Need to act (fast) without confusion Have and Give clear instruction Quick analysis and evaluation Appropriate decision making needs clear criteria Delegated Authority - No time to get a highest level approval/instruction No hesitation to update Same quality at any time and every time

46 Training and Exercise Re-operation just after an urgent operation is completed; evaluation of urgent operation procedure, and UPDATE of SOP if necessary Waveform catalogue/hardcopy; common criteria/threshold (Seismic & Tsunami)

47 Tsunami and Earthquake Monitoring System Operation and maintenance 24 hours a day 7 days a week Battle against time Japan Meteorological Agency 2005/3/9

48 Thank You Masahiro Yamamoto UNESCO/IOC Laura Kong UNESCO/IOC NOAA International Tsunami Information Center Charles McCreery Pacific Tsunami Warning Center

49 PTWC General Processes and Procedures for Initial Tsunami Bulletins STEP 3 STEP 1 Own Seismic Network Cooperating Seismic Networks STEP 2 Data Ingest into Memory Ring(s) Automatic Arrival Detection and Association Automatic Hypocenter Automatic Magnitude STEP 4 Event Alarms STEP 7 Issue Initial Bulletin Compute Tsunami ETAs if a Warning YES Interactive Hypocenter Interactive Magnitude Operator Interactive Review and Refinement EQ Params meet Initial Bulletin Criteria? STEP 6 N STEP 5 W E S

50 PTWC General Processes and Procedures for Initial Tsunami Bulletins STEP 3 STEP 1 1 Own Seismic Network Own Cooperating Seismic Seismic Networks Cooperating Seismic Networks STEP 2 Data Ingest into Memory Ring(s) Automatic Arrival Detection and Association STEP 2 Automatic Hypocenter Automatic Magnitude Data Ingest into Memory Ring(s) Interactive Hypocenter Interactive Magnitude STEP 4 Event Alarms Operator Interactive Review and Refinement STEP 7 Issue Initial Bulletin Compute Tsunami ETAs if a Warning YES EQ Params meet Initial Bulletin Criteria? STEP 6 N STEP 5 W E S

51 STEP 3 PTWC General Processes and Procedures for Initial Tsunami Bulletins W N E STEP 1 Own Seismic Network Cooperating Seismic Networks STEP 2 STEP 2 Data Ingest into Memory Ring(s) Data Ingest into Memory Ring(s) STEP 3 Automatic Arrival Detection and Association Automatic Hypocenter Automatic Magnitude Interactive Hypocenter Interactive Magnitude STEP 5 Automatic Arrival Detection and STEP 4 Association Event Alarms Automatic Hypocenter Operator Interactive Review and Refinement Automatic Magnitude STEP 7 Issue Initial Bulletin Compute Tsunami ETAs if a Warning YES EQ Params meet Initial Bulletin Criteria? STEP 6 S

52 STEP 3 PTWC General Processes and Procedures for Initial Tsunami Bulletins W N E STEP 1 Own Seismic Network Cooperating Seismic Networks Automatic Arrival Detection and STEP 2 Association Data Ingest into Memory Ring(s) Automatic Hypocenter Automatic Magnitude STEP 3 Automatic Arrival Detection and Association Automatic Hypocenter Automatic Magnitude Interactive Hypocenter Interactive Magnitude STEP 5 STEP 4 STEP 4 Event Alarms Event Alarms Operator Interactive Review and Refinement STEP 7 Issue Initial Bulletin Compute Tsunami ETAs if a Warning YES EQ Params meet Initial Bulletin Criteria? STEP 6 S

53 PTWC General Processes and Procedures for Initial Tsunami Bulletins STEP 3 N STEP 1 Own Seismic Network Cooperating Seismic Networks Interactive STEP 2 Hypocenter Data Ingest into Memory Ring(s) Interactive Magnitude Automatic Arrival Detection and Association Automatic Hypocenter Automatic Magnitude Interactive Hypocenter Interactive Magnitude STEP 5 STEP 5 STEP 4 Event Alarms Operator Interactive Review and Refinement Operator Interactive Review and Refinement STEP 7 Issue Initial Bulletin Compute Tsunami ETAs if a Warning YES EQ Params meet Initial Bulletin Criteria? STEP 6 W E S

54 PTWC General Processes and Procedures for Initial Tsunami Bulletins STEP 3 N STEP 1 Own Seismic Network Cooperating Seismic Networks STEP 2 Data Ingest into Memory Ring(s) Automatic Arrival Detection and Association Automatic Hypocenter Automatic Magnitude Operator Interactive Interactive Hypocenter Review and Refinement Interactive Magnitude STEP 5 STEP 4 Event Alarms Operator Interactive Review and Refinement STEP 7 Issue Initial Bulletin Compute Tsunami ETAs if a Warning YES meet Initial EQ Params meet Initial Bulletin Criteria? STEP 6 YES EQ Params Bulletin Criteria? STEP 6 W E S

55 PTWC General Processes and Procedures for Initial Tsunami Bulletins STEP 3 STEP 7 STEP 1 Own Seismic Network Cooperating Seismic Networks STEP 2 Data Ingest into Memory Ring(s) Automatic Arrival Detection and Association Automatic Hypocenter Automatic Magnitude STEP 4 Event Alarms STEP 7 Issue Initial Issue Initial Bulletin Compute Tsunami ETAs if a Warning Interactive Hypocenter Interactive Magnitude Operator Interactive Review and Refinement Compute YES Tsunami ETAs if a Warning EQ Params meet Initial Bulletin Criteria? STEP 6 N STEP 5 W E YES S

56 Tsunami Observation System of JMA 66 stations float type and Huge tsunami gauge Since stations and Acoustic type 29 stations Huge tsunami gauge Huge tsunami gauge Huge tsunami gauge Is a water pressure gauge to measure a running height of so huge a tsunami as to swallow tidal stations. Minami Torishima island Pressure gauge for distant tsunami float type or Acoustic type 1967 Tidal data was started to be transmitted to the nearest observatory in real time and telegraphed to the tsunami warning center Acoustic type tsunami gauges and huge tsunami gauges were installed. Tidal data of another organizations is also transmitted to JMA in real time for tsunami observation.

57 Dissemination of Tsunami Warning to Residents satellite Local Governments Local Meteorological Observatory Polices,Fir e office Residents Dedicated telephone line TV JMA Tsunami Warning Center Government Radio Etc.

58 Limitations and Challenges (1) Real-time forecasting is of limited use for local warning. Self-evacuation might be the only way to avoid the loss of lives. Real-time forecast is only as good as the EQ parameters. Initial EQ mag can be easily off by 0.2 or more, resulting in factor of two difference in wave amplitude. Green s law amplitude can underestimate harbor resonances and overestimate for small islands. The extent of inundation/flooding cannot be determined from the RIFT forecast.

59 Limitations and Challenges (2) How to make accurate forecast for coastal regions with a wide continental shelf (Thailand, Australia, etc.). Ultra fine resolution might not be feasible in real time. Couple with inundation models or using nested grids to refine coastal forecast? Real-time DART inversion is not yet available for RIFT but it is desirable. Landslide model (currently simply slump model) Asteroid Tsunami Meteorological tsunamis

60 Limitations of Tsunami Forecasting Estimated Arrival Time Forecast Based on initial seismic analysis Point source or assumed finite fault Initial Threat Level Forecast Based only on initial seismic analysis and general geophysical/oceanographic contraints Least accurate Sea Level Constrained Forecast Too late for local tsunami Deep ocean measurements best constraint More accurate

61 Limitations of Seismic Analysis Finite Faults Fault rupture over large area Amount of slip varies along fault Depth of ruptured fault varies Tsunamigenesis varies Important near the earthquake Not so important for distant tsunami Finite fault analysis too slow for local warning

62 Why Is There Need to Know? Knowledge of TWC Limitations Helps Guide SOP Development Helps Foster Realistic Expectations Motivates Personal Responsibility

63 Tsunami Travel Times from Large Source

64 Parameter management and tuning Sensitivity of seismometer; correct magnitude estimation Tuning of trigger parameter; reduce the false alarm and shorten the detection of earthquake occurrence All staff need to recognize the importance of the parameters used in the system It takes a long time to find out the most appropriate parameters (KEY; Automatic solution).