TSUNAMI HAZARD MITIGATION ACTIVITIES IN CALIFORNIA

Transcription

1 10NCEE Tenth U.S. National Conference on Earthquake Engineering Frontiers of Earthquake Engineering July 21-25, 2014 Anchorage, Alaska TSUNAMI HAZARD MITIGATION ACTIVITIES IN CALIFORNIA R. I. Wilson 1, K. M. Miller 2, A. Admire 3, J. Borrero 4, E. Curtis 5, L. Dengler 6, M. Eskijian 7, P. Lynett 4, C. Pridmore 8, and H. K. Thio 9 ABSTRACT The California Tsunami Program, comprised of the California Office of Emergency Services (Cal-OES), California Geological Survey (CGS) and funded through the National Tsunami Hazard Mitigation Program (NTHMP) and the Federal Emergency Management Agency (FEMA), works with other governmental, academic, and industry experts to improve tsunami preparedness and mitigation in coastal communities. The program has utilized information from the February 27, 2010 Chile and March 11, 2011 Japan tsunamis, which caused dramatic loss of life and damage in the near-source region and notable impacts in California. Although neither event caused significant inundation of dry land in California, dozens of harbors sustained damage totaling approximately $100 Million. Information gathered from these events has helped influence new tsunami hazard mitigation strategies and identify the need to develop new map tools as potential basis for derivative products for emergency response, maritime, and land-use planners as well as design guidance pertaining to the engineering and construction industry. Scenario-specific, tsunami evacuation playbook maps and guidance documents are being produced detailing inundation from tsunamis of various size and source location. An analytical tool called FASTER is also being developed to integrate storm, tides, modeling errors, and local tsunami run-up potential with the forecasted tsunami amplitudes in real-time when a tsunami Alert is sent out. These products will help communities better implement evacuations and response activities for minor to moderate (less than maximum) tsunami events. 1 Senior Engineering Geologists, California Geological Survey, Sacramento, CA 2 Research Specialist, California Governor s Office of Emergency Services, San Francisco, CA 3 Research Assistant, Humboldt State University, Arcata, CA 4 Professor, University of Southern California, Los Angeles, CA 5 Coastal Engineer, Federal Emergency Management Agency, Region IX, Oakland, CA 6 Professor, Humboldt State University, Arcata, CA 7 Senior Engineer, California State Lands Commission, Los Angeles, CA 8 Engineering Geologist, California Geological Survey, Sacramento, CA 9 Senior Seismologist, URS Corporation, Los Angeles, CA Wilson, RI, Miller, KM, Admire, A, Borrero, J., Curtis, E., Dengler, L, Eskijian, M, Lynett, P, Pridmore, C, Thio HK. Tsunami hazard mitigation activities in California. Proceedings of the 10 th National Conference in Earthquake Engineering, Earthquake Engineering Research Institute, Anchorage, AK, 2014.

2 Evaluation of observed and modeled currents as well as damage to maritime facilities are being used to produce in-harbor tsunami hazard maps for current speeds and duration, and to identify offshore safety zones for potential vessel evacuation during future distant source events. The significant damage to exposed communities in Japan provided incentive for California to develop probability-based products, appropriate for land-use planning under the California Seismic Hazard Mapping Act. These products could also be integrated into multiple other applications, including the new building codes being developed for tsunami loads. Real-time and post-tsunami CGS field teams have been expanded to capture additional detailed information that can be shared in real-time and after an event through a statewide clearinghouse. Data collected from these field teams has and will continue to assist both Cal-OES and FEMA in their post-disaster evaluation process. All products and their applications will be made available to affected coastal California communities for integration into their Local Hazard Mitigation Plans, Local Coastal Programs, and the State Hazard Mitigation Plan. In addition, guidance and best practices developed for and by these products will be reviewed by the NTHMP via member agencies, states, provinces, and territories to help determine opportunities for application and appropriate national implementation. This is the only established national program with demonstrated ability to deliver seamless and consistent public safety messaging, products, applied effectively at the local level to citizens on the ground, at the coast, ahead of the next tsunami.

3 Tsunami Hazard Mitigation Activities in California R. I. Wilson 2, K. M. Miller 2, A. Admire 3, J. Borrero 4, E. Curtis 5, L. Dengler 6, M. Eskijian 7, P. Lynett 4, C. Pridmore 8, and H. K. Thio 9 ABSTRACT The California Tsunami Program, comprised of the California Office of Emergency Services (Cal- OES), California Geological Survey (CGS) and funded through the National Tsunami Hazard Mitigation Program (NTHMP) and the Federal Emergency Management Agency (FEMA), works with other governmental, academic, and industry experts to improve tsunami preparedness and mitigation in coastal communities. The program has utilized information from the February 27, 2010 Chile and March 11, 2011 Japan tsunamis, which caused dramatic loss of life and damage in the near-source region and notable impacts in California. Although neither event caused notable inundation of dry land in California, dozens of harbors sustained damage totaling approximately $100 Million. Information gathered from these events has helped influence new tsunami hazard mitigation strategies and identify the need to develop new map tools as potential basis for derivative products for emergency response, maritime, and land-use planners as well as design guidance pertaining to the engineering and construction industry: Scenario-specific, tsunami evacuation playbook maps and guidance documents are being produced detailing inundation from tsunamis of various size and source location. An analytical tool called FASTER is also being developed to integrate storm, tides, modeling errors, and local tsunami run-up potential with the forecasted tsunami amplitudes in real-time when a tsunami Alert is sent out. These products will help communities better implement evacuations and response activities for minor to moderate (less than maximum) tsunami events. Evaluation of observed and modeled currents as well as damage to maritime facilities are being used to produce in-harbor tsunami hazard maps for currents and event duration, and identify offshore safety zones for potential boat evacuation during future distant source events. The significant damage to exposed communities in Japan provided incentive for California to develop probability-based products, appropriate for land-use planning under the California Seismic Hazard Mapping Act. These products could also be integrated into multiple other applications, including the new building codes being developed for tsunami loads. 1 Senior Engineering Geologists, California Geological Survey, Sacramento, CA 2 Research Specialist, California Governor s Office of Emergency Services, San Francisco, CA 3 Research Assistant, Humboldt State University, Arcata, CA 4 Professor, University of Southern California, Los Angeles, CA 5 Coastal Engineer, Federal Emergency Management Agency, Region IX, Oakland, CA 6 Professor, Humboldt State University, Arcata, CA 7 Senior Engineer, California State Lands Commission, Los Angeles, CA 8 Engineering Geologist, California Geological Survey, Sacramento, CA 9 Senior Seismologist, URS Corporation, Los Angeles, CA Wilson, RI, Miller, KM, Admire, A, Borrero, J., Curtis, E., Dengler, L, Eskijian, M, Lynett, P, Pridmore, C, Thio HK. Tsunami hazard mitigation activities in California. Proceedings of the 10 th National Conference in Earthquake Engineering, Earthquake Engineering Research Institute, Anchorage, AK, 2014.

4 Real-time and post-tsunami CGS field teams have been expanded to capture additional detailed information that can be shared in real-time and after an event through a state-wide clearinghouse. Data collected from these field teams has and will continue to assist both Cal- OES and FEMA in their post-disaster evaluation process. All products and their applications will be made available to affected coastal California communities for integration into their Local Hazard Mitigation Plans, Local Coastal Programs, and the State Hazard Mitigation Plan. In addition, guidance and best practices developed for and by these products will be reviewed by the NTHMP via member agencies, states, provinces, and territories to help determine opportunities for application and appropriate national implementation. This is the only established national program with demonstrated ability to deliver seamless and consistent public safety messaging, products, applied effectively at the local level to citizens on the ground, at the coast, ahead of the next tsunami. Introduction The State of California tsunami program is a hazard-reduction program managed by the California Governor s Office of Emergency Services (Cal-OES) with assistance from the California Geological Survey (CGS) and tsunami experts from other government agencies, academic institutions, and private companies. The program promotes tsunami planning, preparedness and hazard mitigation among California s coastal communities and participates in the National Tsunami Hazard Mitigation Program (NTHMP), which is responsible for setting U.S. policy and guidance for tsunami warning and long-term planning. Within the state, the program works through the California Tsunami Steering Committee with its 20 coastal and Bay Area county emergency management partners and other state and federal agencies with tsunami hazard responsibilities. Most of the activities of the state program are funded through partnerships with the NTHMP and the Federal Emergency Management Agency (FEMA). The state tsunami program has first sought to identify and characterize the tsunami hazard in California and then integrate this knowledge into the state s emergency management system and hazard mitigation efforts, including: 1) tsunami scenario modeling; 2) inundation zone maps/evacuation zone mapping; 3) state/local emergency response and evacuation planning; 4) exercises and training; 5) warning system testing; and, 6) NTHMP coordination and support. With the assistance of numerical modeling partners at the University of Southern California (USC), the state completed tsunami inundation modeling for all low-lying, populated sections of the California coast resulting in 130 maps [1,2]. The maps denote maximum tsunami inundation from a variety of local and distant tsunami sources to assist coastal jurisdictions with evacuation planning. Recent Tsunamis and Scenario Evaluations Since 1800, over 100 tsunamis have been observed or recorded in California [3,4]. While the majority of these events were small and detected only by tide gauges, thirteen were large enough to cause damage and five events have caused deaths. Table 1 shows impacts from a number of the more significant tsunamis in the past 70 years as well as analysis from two recently completed tsunami source scenarios: 1) a magnitude 9.1 earthquake along the western Alaska trench (USGS Science Application for Risk Reduction-SAFRR project; Ross and Jones,

5 2013)[5], and 2) a magnitude 9 earthquake along the Cascadia Subduction Zone [6]. The most significant tsunami to impact California was the March 27, 1964 Alaska event, flooding 29 blocks of Crescent City and killing 13 people statewide. Table 1. Historical tsunami impacts from notable distant-source events over the past 70 years. The USGS SAFRR and Cascadia scenario tsunamis are also summarized. Significant Historical Distant Source Tsunamis (year-magnitude-source location) 1946 M8.1 Eastern Aleutian Islands Tsunami Amplitudes for Historical Events, from NGDC Database (in meters above normal tide conditions; - means no data available) Crescent City San Francisco Half Moon Bay Port of Los Angeles San Diego Bay Effects in California (damage value is presented in constant dollars, representing that year and not adjusted for inflation) One fatality; significant inundation in Half Moon Bay; damage approached several million dollars 1960 M9.5 Chile M9.2 Alaska M8.3 Kuril Islands M8.8 Chile M9.0 Japan Two fatalities; inundation in Crescent City; damage approached several million dollars Thirteen fatalities; significant inundation in Crescent City; damage approached $20M Damage to docks in Crescent City approached $20M Damage to 12 harbors approached $3M One fatality; damage to 27 harbors approached $100M Numerical Modeling of SAFRR Western Alaska Scenario Catastrophic Cascadia Scenario (FEMA and CalOES) Projected: Inundation widespread; damage exceeds 10-Billion dollars Projected: Flooding extensive in Crescent City, low-lying coastal areas in northern state After the 2010 Chile and 2011 Japan tsunamis, post-event survey teams and questionnaires were used to gather information on both the physical effects of the tsunamis and the emergency response activities by local jurisdictions [7]. The 2010 tsunami caused approximately $3 Million in damage to a dozen harbors in California, while the 2011 tsunami caused over $100 Million in damage to 27 harbors. During both events, people on docks and near the ocean were at risk to injury with one fatality occurring during the 2011 tsunami at the mouth of the Klamath River. In addition, the significant sediment deposition and damage within Crescent City and Santa Cruz harbors during the 2011 event caused long delays in recovery of those harbors because of regulatory and reconstruction issues [8]. Even with the fatality and damage to harbors, California has been fortunate that the most significant tsunami surge activity for both the 2010 and 2011 tsunamis, as well as several of the historically larger events, occurred coincident with relatively

6 low-tide conditions along the coast, greatly reducing the amount of inundation and more severe damage [7]. Although evaluations of tsunamis in California present a brief history to date, evaluations have been completed in recent years to help plan for other worst-case tsunami scenarios from both distant and local sources. The state program partnered with the USGS SAFRR project to evaluate the effects from a tsunami generated by a magnitude 9.1 earthquake on the western Alaska trench, the distant-source region identified as having the most impact along the California coast [1,9,10]. The SAFRR project identified that a quarter of a million residents would likely need to be evacuated in a very short period of time (4-6 hours), and that there would be at least $10 Billion of damage and recovery costs statewide [5]. The state and FEMA also recently completed a study of the earthquake and tsunami impacts of a magnitude 9.0 earthquake on the Cascadia Subduction Zone, which could rupture an offshore fault length of 800 mi (1280km) paralleling the coast from Cape Mendocino in California to British Columbia, Canada [6]. In addition to causing extensive inundation to Crescent City and other low-lying areas in Del Norte and Humboldt counties, long-term recovery issues will impact the northern California area for decades to come. Based on the analysis of these recent events in Chile, Japan, and California, and the information provided by the SAFRR and Cascadia scenarios, the state tsunami program is enhancing existing products and developing new products that will improve tsunami preparedness and mitigation statewide [7,8]. These products will help: (1) emergency managers to develop evacuation plans for smaller Warning level events where extensive evacuation is not required; (2) the maritime community better understand tsunami hazards within their ports and harbors, as well as if and where boats should go offshore to be safe; and (3) coastal land-use planners, engineers and policymakers better understand the tsunami hazard from a probabilistic (risk-based) approach. Tsunami field teams have also been expanded to provide additional information before, during, and after a tsunami. The ultimate goal of these improvements is to save lives and reduce immediate and long-term impact of tsunamis to coastal communities. Tsunami Evacuation Playbooks Recent minor to moderate Warning alert-level tsunami events in California have challenged existing evacuation protocols which typically call for evacuation of all low-lying areas to 30-to- 60 m elevation. During the 2011 tsunami in California, the arrival of the significant tsunami activity, forecasted to be between 1 and 2.5 m for areas within a Warning alert level along the coast, coincided with low tide conditions and, therefore, was not expected to inundate dry land. Considerable inconsistencies between communities conducting evacuation and response were noted [7]. Only a few communities in the state called for full evacuations and, in most cases, no evacuations were initiated. Many emergency managers indicated that secondary evacuation lines for smaller Warning-level events would have been useful, reducing the potential for under or over evacuation and alleviating the need for an all or nothing decision. As a result, scenariospecific, tsunami evacuation playbook maps and guidance recommendations are being produced detailing inundation from tsunamis of various sizes and source locations (Fig. 1)[11]. Playbook evacuation lines would be recommended for use only with significant time, likely more

7 than 5 hours, to plan a secondary evacuation. Playbooks for local and regional sources like the Cascadia Subduction Zone will also identify the likely inundation areas for these events from numerically modeled data. In addition, a formula that incorporates forecasted tsunami amplitudes (wave heights), tidal conditions, storm activity, and site specific tsunami run-up potential into a maximum predicted tsunami run-up height is being developed to determine which evacuation scenario is most appropriate and conservative to use. These products, expected to be available in 2014, will help coastal emergency managers prepare local response plans when minor/moderate distant source tsunamis or larger tsunamis from local and regional sources are generated. Figure 1. Example of tsunami scenario playbook evacuation lines for the City of Imperial Beach, California. These evacuation lines could be used for evacuation planning and response activities during minor to moderate tsunami Warning level events. Modified from [11]. Maritime Planning Products Maritime communities in California were impacted the most during the 2010 and 2011 tsunamis, and could be again as demonstrated by the SAFRR and Cascadia tsunami scenarios. Although millions of dollars were lost during the 2010 and 2011 events, the eye-witness accounts and video information collected after each event provided a resource for improving tsunami hazard analysis in ports and harbors [8,12,13]. Through a Co-operative Technical Partnership developed between the state and FEMA, observed strong tsunami currents and areas of damage are being used to validate/calibrate numerical tsunami model currents. In addition, a maritime damage index was used to determine the relationship between tsunami currents and damage severity (Fig. 2)[13]. Using validated modeling, hazard maps with these four current-damage categories are generated to identify areas of potential damage within harbors from multiple modeled scenarios (Fig. 3).

8 Figure 2. Graph showing relationship between predicted and observed tsunami currents and damage to maritime facilities. Four groups of current-based damage categories are identified. Modified from [13]. The state tsunami program has initiated a plan to develop three sets of products for these maritime communities: (1) detailed maps identifying in-harbor tsunami hazards, such as strong currents and eddies, peak amplitude surges, and large water level fluctuations, as well as the potential duration of hazardous currents and safe areas within harbors; (2) offshore safety zones and low current areas within harbors where ships can evacuate to and safely gather during a tsunami; and (3) preparedness, mitigation, and recovery/continuity plans to help maritime communities be more resilient to tsunami hazards. To help identify the safe water depth during various large tsunamis, evaluations of maximum, numerically modeled tsunami currents versus water depth demonstrate that non-damaging, straight-line currents greater than 3 knots (1.5 m/sec) do not generally occur at water depths greater than 30 fathoms (54 m). Therefore, this likely represents a safe depth for offshore evacuation (Fig. 4). Harbor-specific guidance will be created to help maritime communities better prepare for, respond to, and recover from future tsunamis. Most of this mapping and guidance work with the maritime communities will be completed by the year 2015.

9 Figure 3. Maps of Ventura Harbor showing four damage categories related to current groups of <3, 3-6, 6-9, and >9 knots (see Fig. 2 for further explanation). Left image shows tsunami current hazard map for the 2011 Japan tsunami, and right image represents the combination of all modeled large tsunami scenarios, which includes scenario sources from the Aleutian Islands, Chile, and offshore faults and landslides. Figure 4. Scatter plot of maximum modeled tsunami currents versus water depth. A depth greater than 30 fathoms (54 m) is likely a safe water depth for boats because non-damaging, straight-line currents occur beyond this depth. Modified from [13].

10 Probability-based Products for Land-Use Along with improvements to evacuation planning and maritime planning, the state tsunami program has made progress towards development of products for the coastal land-use planning, engineering, and policymaking communities. In 1990, the California Legislature authorized the CGS to prepare maps delineating zones of tsunami hazard, when it was viable to do so, as part of the Seismic Hazard Mapping Act (Public Resources Code, sec 2690 et seq.). This State Law contains provisions that require regulated land use development and building construction in hazard zones by requiring site-specific hazard investigations and the inclusion of appropriate mitigations into any approved development and construction projects within these zones. Because the existing state-wide tsunami inundation maps are based on maximum inundating maps and not a time- or risk-based approach, they should not be used for making land-use planning decisions. As with other flood and seismic hazards, a probabilistic tsunami hazard analysis (PTHA) should be completed and utilized. Maps and associated products based on PTHA methods will be similar to other probabilistic flood and seismic hazard maps by representing standard risk levels (average return periods) for tsunami hazards which can be used in not only land-use planning but possibly also implementing building design criteria, producing more consistent inundation maps for evacuation planning, and setting flood insurance rates. CGS created a voluntary panel of experts known as the California PTHA Work Group to review existing and new PTHA methods and products of the principal investigators at URS Corporation [14] and the University of Washington [15], and provide feedback on what improvements should be made for developing products in the future. The initial phase of PTHA and land-use planning product development, which has been funded by the NTHMP, includes: (1) determination of the adequacy of the PTHA methods for land-use planning and other uses; (2) acceptance and improvements made to the PTHA methods; (3) determination of the appropriate risk levels for PTHA-based map production; and, (4) initiation of development of PTHA-based maps for the California coast. With this initial work completed, the state tsunami program is collaborating with other entities interested in developing PTHA maps for the entire California coastline [16]. Expanded Field Teams and Information Clearinghouse During the 2011 Japan tsunami in California, four field team members were deployed to the coastal region before the tsunami arrival to make real-time observations and transmit that information back to the centralized clearinghouse that integrated it into the State response plan. After the event, questionnaires were sent to the maritime communities and State Beach representatives to inquire about both physical effects and emergency response efforts during the tsunami. This was followed up by deployment of eight field teams made up of scientists and engineers to interview maritime and State Beach personnel and document damage, resulting in collection of data at 160 sites along the coast. This information was utilized by CalOES and FEMA to demonstrate that portions of California deserved federal disaster relief funding, saving the state approximately $28 Million [7]. Response activities before, during and after the March 11, 2011 tsunami demonstrated that this

11 field team program can provide useful, real-time data to a state-level clearinghouse to improve emergency management decisions. CGS and CalOES have worked over the past year to expand the pre- and post-event field response teams. The anticipated goals of this expanded program include deploying geoscience field observers and data collectors prior to a tsunami s arrival and establishing a formal state-level information clearinghouse for state, federal, and local emergency managers to use during and after a tsunami. Significant progress has been made in establishing the foundation of the project, producing the field protocol, enlisting the volunteers for field work, and maintaining the field teams for future years. National Coordination and Application CGS and CalOES participation with other state and federal partners in the NTHMP has created a synergy that will improve tsunami hazard preparedness and mitigation efforts in California and the rest of the nation. The expertise provided by state and federal partners through the NTHMP Mapping and Modeling Subcommittee and various work groups have been vital to validating California s new mapping and program efforts [17]. Likewise, the process and products of these activities in California will form the basis for the NTHMP to develop consistent guidance for other states, which was a recommendation of the 2011 National Academy of Science report [18] on national tsunami preparedness activities and the 2013 NTHMP Strategic Plan [19]. National guidelines for the creation and application of the tsunami evacuation playbooks, maritime preparedness products, land-use planning products, and field teams will be completed in Conclusions The California tsunami program will continue to develop new tools and provide support to communities at risk to tsunami hazards. Evaluations of recent tsunamis and tsunami scenarios have resulted in the development of new products to help evacuation planning, maritime planning, and land-use planning. Playbooks for less-than-maximum tsunami events and local and regional scenarios will allow communities to more accurately identify and plan for the areas to evacuate during future tsunamis. Tsunami current hazard maps within harbors and offshore safety zones will provide maritime communities a foundation for developing and improving emergency response and business continuity plans. New tsunami maps developed using probabilistic-based methods will assist in community land-use planning, site evaluations, and other risk-based uses. Expansion of tsunami field teams to deploy during and after future tsunamis will provide real-time assessments to emergency managers and post-event assessments to recovery specialists at the federal, state, and local levels. Ultimately, this work in California will lead to national guidance to provide consistent procedures for development of accurate products for tsunami hazard preparedness, mitigation, and recovery efforts. References 1. Wilson, R.I., Barberopoulou, A., Miller, K.M., Goltz, J.D., and Synolakis, C.E., 2008, New maximum tsunami inundation maps for use by local emergency planners in the State of California, USA: EOS Trans. American Geophysical Union 89(53), Fall Meeting Supplement, Abstract OS43D-1343.

12 2. Barberopoulou, A., Borrero, J.C., Uslu, B., Kalligeris, N., Goltz, J.D., Wilson, R.I., and Synolakis, C.E., 2009, New maps of California to improve tsunami preparedness: EOS Trans. American Geophysical Union, 90 (16), pp Lander, J., Lockridge, P.A., and Kozuch, J., 1993, Tsunamis affecting the west coast of the United States : NGDC Key to Geophysical Research Documentation No. 29, USDOC/NOAA/NESDIS/NGDC, Boulder, CO, USA, 242 pp. 4. National Geophysical Data Center (NGDC), 2013, National Geophysical Data Center Historic Tsunami Data Base at: 5. Ross, S.L., and Jones, L.M., eds., 2013, The SAFRR (Science Application for Risk Reduction) Tsunami Scenario: U.S. Geological Survey Open-File Report and California Geological Survey Special Report 229, 17 p., 6. Federal Emergency Management Agency (FEMA) and California Office of Emergency Services (CalOES), 2013, Cascadia Subduction Zone Earthquake and Tsunami Response Plan: joint FEMA and CalOES publication. 7. Wilson, R.I., Admire, A.R., Borrero, J.C., Dengler, L.A., Legg, M.R., Lynett, P., Miller, K.M., Ritchie, A., Sterling, K., McCrink, T.P., Whitmore, P.M., 2012a, Observations and impacts from the 2010 Chilean and 2011 Japanese tsunami in California (USA): Pure and Applied Geophysics z. 8. Wilson, R., Davenport, C., and Jaffe, B., 2012b, Sediment scour and deposition within harbors in California (USA), caused by the March 11, 2011 Tohoku-oki Tsunami: Sedimentary Geology, doi: /j.sedgeo Thio, H.K., 2010, Probabilistic tsunami hazard analysis in California Year One: Pacific Earthquake Engineering Research (PEER) Center Lifelines Project #10A Uslu, B., 2011, Deterministic and probabilistic tsunami analyses of California: University of Southern California, PhD dissertation. 11. Wilson, R., and Miller, K., in press, Tsunami emergency response playbooks and FASTER tsunami height calculation: Background information and guidance for use: California Geological Survey Special Report. 12. Admire, A., Dengler, L., Crawford, G., Uslu, B., Borrero, J., Greer, D., Montoya, J., and Wilson, R., in press, Observed and modeled currents from the Tohoku-oki, Japan and other recent tsunamis in northern California: Pure and Applied Geophysics. 13. Lynett, P., Borrero, J., Son, S., Wilson, R., and Miller, K., in preparation, Assessment of current-induced tsunami hazards for maritime planning: Geophysical Research Letters. 14. Thio, H.K., 2013, Probabilistic Tsunami Hazard at Crescent City: URS Corporation Report, 43 p. 15. Gonzalez, F.I., LeVeque, R.J., and Adams, L.M., 2013, Probabilistic Tsunami Hazard Assessment (PTHA) for Crescent City, CA, Final Report on Phase I, January 31, 2013: University of Washington Report, 70 p. 16. California Probabilistic Tsunami Hazard Analysis (PTHA) Work Group, in press, Evaluation and application of probabilistic tsunami hazard analysis in California: California Geological Survey Special Report. 17. Wilson, R., and Eble, M., 2013, New activities of the U.S. National Tsunami Hazard Mitigation Program, Mapping and Modeling Subcommittee: presentation at 2013 American Geophysical Union Fall Meeting, San Francisco, California. 18. National Academy of Sciences, 2011, Tsunami warning and preparedness: An assessment of the U.S. Tsunami Program and that nation s preparedness efforts: The National Academies Press, 296 p. 19. National Tsunami Hazard Mitigation Program (NTHMP), 2013, National Tsunami Hazard Mitigation Program Strategic Plan, published May 30, 2013, 32 p.;