MO D AT SPH AN ER I IC C N A A D E M C I N O I S L T A R N A O T I I T O A N N U . NOAA OAR Special Report S . E D C E R P E AR M TM OM ENT OF C PMEL Tsunami Forecast Series: Vol. 1 A Tsunami Forecast Model for Hilo, Hawaii Liujuan Tang Vasily V. Titov Christopher D. Chamberlin Hilo Hilo NOAA Center for Tsunami Research (NCTR) Pacic Marine Environmental Laboratory Front cover image: Overview of NOAA tsunami forecast system. Top frame illustrates components of the tsunami forecast using the 15 November 2006 Kuril Islands tsunami as an example: DART systems (black triangles), pre- computed tsunami source function database (unfilled black rectangles) and high-resolution forecast models in the Pacific, Atlantic, and Indian oceans (red squares). Colors show computed maximum tsunami amplitudes of the off- shore forecast. Black contour lines indicate tsunami travel times in hours. Lower panels show the forecast process sequence left to right: tsunami de- tection with the DART system (third generation DART ETD is shown); model propagation forecast based on DART observations; coastal forecast with high- resolution tsunami inundation model. PDF versions of the PMEL Tsunami Forecast Series reports are available at http://nctr.pmel.noaa.gov/forecast_reports NOAA OAR Special Report PMEL Tsunami Forecast Series: Vol. 1 A Tsunami Forecast Model for Hilo, Hawaii Liujuan Tang1,2,VasilyV.Titov2, and Christopher D. Chamberlin1,2 1Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of Washington, Seattle, WA 2NOAA/Pacific Marine Environmental Laboratory (PMEL), Seattle, WA March 2010 .4/&# % /- 4- - 2 % ! 2 UNITED STATES NATIONAL OCEANIC AND Office of Oceanic and 0 # % % $ DEPARTMENT OF COMMERCE ATMOSPHERIC ADMINISTRATION Atmospheric Research Craig McLean 5 Gary Locke Jane Lubchenco . ! # )4 ) Assistant Administrator % 2 Secretary Under Secretary for Oceans $ % 3 !- 4!4%3/& and Atmosphere/Administrator NOTICE from NOAA Mention of a commercial company or product does not constitute an endorsement by NOAA/OAR. Use of information from this publication concerning proprietary products or the tests of such products for publicity or advertising purposes is not authorized. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the au- thors and do not necessarily reflect the views of the National Oceanic and Atmospheric Admin- istration. Contribution No. 3340 from NOAA/Pacific Marine Environmental Laboratory Contribution No. 1766 from Joint Institute for the Study of the Atmosphere and Ocean (JISAO) Also available from the National Technical Information Service (NTIS) (http://www.ntis.gov) ii Contents iii Contents List of Figures v List of Tables vii Foreword ix Abstract 1 1 Background and Objectives 1 2 Forecast Methodology 3 2.1 Construction of a tsunami source based on DART observations andtsunamisourcefunctions...................... 3 2.2 Real-time coastal predictions by high-resolution forecast models 4 3 Model Development 7 3.1 Forecastareaandtsunamidata..................... 7 3.2 Bathymetryandtopography....................... 8 3.3 Gridsetups................................. 10 4 Results and Discussion 13 4.1 Sensitivity of modeled time series by the Hilo forecast model to gridcouplingschemes.......................... 13 4.2 Validation,verification,andtestingoftheforecastmodel..... 13 4.2.1 Validation............................. 13 4.2.2 Verification............................ 16 4.2.3 Robustnessandstabilitytests................. 16 4.3 Tsunami hazard assessment for Hilo from simulated magnitude 7.5,8.2,8.7,and9.3tsunamis...................... 17 5 Summary and Conclusions 19 6 Acknowledgments 19 7 References 21 FIGURES 25 Appendix A 51 A1. Referencemodel*.infileforHilo,Hawaii............... 51 A2. Forecastmodel*.infileforHilo,Hawaii................ 51 Appendix B Propagation Database: Pacific Ocean Unit Sources 53 Glossary 91 Contents v List of Figures 1 Photos showing damage at Hilo caused by the (a–e) 1946 and (f) 1960 tsunamis (images courtesy of Pacific Tsunami Museum) . .... 27 2 OverviewoftheTsunamiForecastSystem................. 28 3 AnaerialphotoofHilo(imagefromGoogleEarth)............ 29 4 Population density, Hawaii (source: 2000 Census). .......... 30 5 Bathymetric and topographic data source overview for the Hawaiian Islands with 6-arc-sec (∼180m)resolution................. 31 6 Bathymetric and topographic data source overview for Hilo with 1/3-arc-sec (∼10m)resolution........................ 32 7 Grid setup for the Hilo reference model with resolution of (a) 36 (1080 m), (b) 6 (180 m) and (c) 1/3 (10m)............... 33 8 Grid setup for the Hilo forecast model with resolutions of (a) 120 (3600 m), (b) 18 (540 m) and (c) 2 (60m)................ 34 9 Tsunami time series at Hilo tide station computed by the MOST with one- and two-way coupling schemes from the Hilo forecast for 16 pasttsunamis.................................. 35 10 Tsunami time series of observed and modeled amplitudes by the Hilo reference inundation model and the forecast model for the 16 pasttsunamis.................................. 36 11 (a) Error of the maximum wave height, and (b) peak wave period from observations and results computed by the Hilo forecast model . 40 12 Time series of observed and forecast wave amplitudes at Hilo tide gauge computed by the Hilo forecast model in real time during the November 2006 Kuril Islands tsunami ................... 41 13 (a) Maximum water elevations at Hilo computed by the forecast model for the 1946 Unimak tsunami. (b) Comparison between com- puted inundation in (a) and survey data from Shepard et al. (1950). 42 14 Computed maximum amplitude and speed by the (a and b) Hilo ref- erence model and (c and d) forecast model for the 14 past tsunamis..................................... 43 15 Modeled tsunami time series by the Hilo reference model and fore- castmodelfor18simulatedmagnitude9.3tsunamis.......... 45 16 Maximum water elevation computed by the (a) Hilo reference model and (b) forecast model for the 18 simulated magnitude 9.3 tsunamis..................................... 47 17 Maximum water elevation at (a) Hilo offshore from the propaga- tion database and (b, c, d, and e) at Hilo tide station computed by the forecast model for simulated magnitude 7.5, 8.2, 8.7, and 9.3 tsunamis..................................... 49 18 Maximum computed water elevation at offshore deep water and coastal tide stations in (a) logarithmic and (b) Cartesian coordinates 50 B1 Aleutian–Alaska–CascadiaSubductionZoneunitsources........ 55 B2 CentralandSouthAmericaSubductionZoneunitsources....... 61 B3 EasternPhilippinesSubductionZoneunitsources............ 69 B4 Kamchatka-Kuril-Japan-Izu-Mariana-Yap Subduction Zone unit sources...................................... 71 vi Contents B5 Manus–Oceanic Convergent Boundary Subduction Zone unit sources...................................... 77 B6 NewGuineaSubductionZoneunitsources................. 79 B7 NewZealand–Keradec–TongaSubductionZoneunitsources...... 81 B8 NewBritain–Solomons–VanuatuZoneunitsources............ 85 B9 Ryukyu–Kyushu–NankaiZoneunitsources................. 89 Contents vii List of Tables 1 Tsunamisourcesfor16historicaltsunamis................. 9 2 MOST setup of the reference and forecast models for Hilo, Hawaii. 10 B1 Earthquake parameters for Aleutian–Alaska–Cascadia Subduction Zoneunitsources............................... 56 B2 Earthquake parameters for Central and South America Subduction Zoneunitsources................................ 62 B3 Earthquake parameters for Eastern Philippines Subduction Zone unit sources...................................... 70 B4 Earthquake parameters for Kamchatka-Kuril-Japan-Izu-Mariana-Yap SubductionZoneunitsources........................ 72 B5 Earthquake parameters for Manus–Oceanic Convergent Boundary SubductionZoneunitsources........................ 78 B6 Earthquake parameters for New Guinea Subduction Zone unit sources...................................... 80 B7 Earthquake parameters for New Zealand–Keradec–Tonga Subduc- tionZoneunitsources............................. 82 B8 Earthquake parameters for New Britain–Solomons–Vanuatu Subduc- tionZoneunitsources............................. 86 B9 Earthquake parameters for Ryukyu–Kyushu–Nankai Subduction Zone unitsources................................... 90 PMEL Tsunami Forecast Series: Vol. 1 — Hilo, Hawaii ix Foreword sunamis have been recognized as a potential hazard to United States coastal communities since the mid-twentieth century, when multiple T destructive tsunamis caused damage to the states of Hawaii, Alaska, California, Oregon, and Washington. In response to these events, the United States, under the auspices of the National Oceanic and Atmospheric Administration (NOAA), established the Pacific and Alaska Tsunami Warning Centers, dedicated to protecting United States interests from the threat posed by tsunamis. NOAA also created a tsunami research program at the Pacific Marine Environmental Laboratory (PMEL) to develop improved warning products. The scale of destruction and unprecedented loss of life following the December 2004 Sumatra tsunami served as the catalyst to refocus efforts in the United States on reducing tsunami vulnerability of coastal communities, and on 20 December 2006, the United States Congress passed the “Tsunami Warning and Education Act” under which education and warning activities were thereafter specified and mandated. A “tsunami forecasting capability based on models andmeasurements,includingtsunamiinundationmodelsandmaps...”