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Full Text Available With the renewed interest in regional Tsunami Warning Systems and the potential tsunami threats throughout the Caribbean and West coast of the United States, the National Ocean Service (NOS, National Water Level Observation Network (NWLON consisting of 175 primary stations, is well situated to play a role in the National Hazard Mitigation effort. In addition, information regarding local mean sea level trends and GPS derived geodetic datum relationships at numerous coastal locations is readily available for tsunami hazard assessment and mapping applications.Tsunami inundation maps and modeling are just two of the more important products which may be derived from NWLON data. In addition to the seven water level gauges that are hardwired into the West Coast and Alaska Tsunami Warning Center (WClATWC, NOS has a significant number of gauges with real-time satellite telemetry capabilities located along the Pacific Northwest coastline, the Gulf of Mexico and the Caribbean. These gauges, in concert with near shore buoy systems, have the potential for increasing the effectiveness of the existing tsunami warning system.The recent expansion of the Caribbean Sea Level Gauge Network through the NOS regional partnerships with Central American and Caribbean countries have opened an opportunity for a basin-wide tsunami warning network in a region which is ill prepared for a major tsunami event.
James R. Hubbard
Web site developed by the National Oceanic and Atmospheric Administration (NOAA) on issues surrounding tsunamis. It provides an extensive selection of links to information on how tsunamis are created, hazards associated with them, and how individuals and communities can prepare and respond to a tsunami. There is also information about the NOAA's role in tsunami warnings and preparedness, including locations of warning centers in the Pacific Ocean Basin, observations and data, forecasts, and hazard-assessment research and modeling.
The Hellenic NTWC (HL-NTWC) was established officially by Greek Law in September 2010. HL-NTWC is hosted at the National Observatory of Athens, Institute of Geodynamics (NOA-IG), which also operates a 24/7 earthquake monitoring service in Greece and coordinates the newly established Hellenic Unified National Seismic Network. NOA-IG and HL-NTWC Operational Centre is linked to the Civil Protection Operational Centre and serves as the official alerting agency to the General Secretariat for Civil Protection in Greece, regarding earthquake events and tsunami watch. Since August 2012, HL-NTWC acts as Candidate Tsunami Watch Provider (CTWP) under the UNESCO IOC - ICG NEAMTWS tsunami warning system (NEAM: North-Eastern Atlantic, the Mediterranean and connected seas) and offers its services to the NEAMTWS system. HL-NTWC has participated in all Communication Test Exercises (CTE) under NEAMTWS and also it has provided tsunami scenarios for extended system testing exercises such as NEAMWAVE12. Some of the recent developments at HL-NTWC in Greece include: deployment of new tide gauge stations for tsunami watch purposes, computation of tsunami scenarios and extending the database in use, improving alerting response times, earthquake magnitude estimation and testing newly established software modules for tsunami and earthquake alerting (i.e. Early-Est, SeisComP3 etc.) in Greece and the Eastern Mediterranean. Although funding today is limited, an advantage of the participation in important EC funded research projects, i.e. NERIES, NERA, TRANSFER, NEAMTIC and ASTARTE, demonstrates that collaboration of top class Research Institutions that care to produce important and useful results in the research front in Europe, can facilitate towards developing and operating top class Operational Centers, useful for Civil Protection purposes in regions in need. Last, it is demonstrated that HL-NTWC collaboration with important key role Research Centers in the Security and Safety issues (e.g. JRC-IPSC) at the Operational front, can further facilitate and secure everyday operation under a collaborative and experience exchanging manner. This work is funded by project ASTARTE - Assessment, STrategy And Risk Reduction for Tsunamis in Europe. Grant 603839, 7th FP (ENV.2013.6.4-3 ENV.2013.6.4-3)
Melis, Nikolaos S.; Charalampakis, Marinos
The Seychelles were severely affected by the December 26, 2004 tsunami in the Indian Ocean. Since the tsunami history of small islands often remains unclear due to a young historiography we conducted a study of onshore tsunami deposits on the Seychelles in order to understand the scale of impact of the 2004 Indian Ocean tsunami and potential predecessors. As part of this project we found and studied onshore tsunami deposits in the mangrove forest at Old Turtle Pond bay on the east coast of Curieuse Island. The 2004 Indian Ocean tsunami caused a change of habitat due to sedimentation of an extended sand sheet in the mangrove forest. We present results of the first detailed sedimentological study of onshore tsunami deposits of the 2004 Indian Ocean tsunami conducted on the Seychelles. The Curieuse mangrove forest at Old Turtle Pond bay is part of the Curieuse Marine National Park. It is thus protected from anthropogenic interference. Towards the sea it was shielded until the tsunami by a 500 m long and 1.5 m high causeway which was set up in 1909 as a sediment trap. The causeway was destroyed by the 2004 Indian Ocean Tsunami. The silt to fine sand sized and organic rich mangrove soil was subsequently covered by carbonate fine to medium sand (1.5 to 2.1 ?) containing coarser carbonate shell debris which had been trapped outside the mangrove bay before the tsunami. The tsunami deposited a sand sheet which is organized into different lobes. They extend landwards to different inundation distances as a function of morphology. Maximum inundation distance is 200 m. The sediments often cover the pneumatophores of the mangroves. No landward fining trend of the sand sheet has been observed. On the different sand lobes carbonate-cemented sandstone debris ranging in size from 0.5 up to 12 cm occurs. Also numerous mostly fragmented shells of bivalves and molluscs were distributed on top of the sand lobes. Intact bivalve shells were mostly positioned with the convex side upwards. On small ledges of a granitic body at 120 m from the shore fragmented and complete shells were deposited at different elevations of up to 4 m. This implies a run up height of at least 4 m above sea level at this distance from the shore. Our study presents the mapping of the tsunamigenic sand lobes, their grain size distribution and petrographic variations of their components compared to the mangrove soil. The difference in the grain size and amount of organic material of the mangrove soil compared to the sand lobes indicate that the coarser material was entrained from outside of the mangrove forest by the tsunami. The similarity of the grain size distributions of the sediment of the sand lobes and of a reference beach/intertidal sample suggests the lagoon between the mangrove forest and the causeway as the probable sediment source area. The fact that the mangrove forest is surrounded by granitic hills and the appearance of the carbonate sandstone debris mostly on the surface of the sand sheets supports this assumption.
Nentwig, V.; Bahlburg, H.; Monthy, D.
This paper describes a kinematic model that computes tsunamis generated from submarine landslides. The model is based on bathymetric (ocean floor modeling) data and historical tsunami data. The papers' main focus is the application of the model to the 1741 Oshima-Oshima Tsunami in Japan and landslide events around the Hawaiian Islands. This paper was presented at the U.S. National Tsunami Hazard Mitigation Program Review and International Tsunami Symposium in Seattle, Washington on August 10, 2001.
Satake, Kenji; National Oceanic and Atmospheric Administration (NOAA)
Full Text Available Human immediate response is contextualized into different time compartments reflecting the tsunami early warning chain. Based on the different time compartments the available response time and evacuation time is quantified. The latter incorporates accessibility of safe areas determined by a hazard assessment, as well as environmental and demographic impacts on evacuation speed properties assessed using a Cost Distance Weighting GIS approach.
Approximately 4.35 million Indonesians live in tsunami endangered areas on the southern coasts of Sumatra, Java and Bali and have between 20 and 150 min to reach a tsunami-safe area. Most endangered areas feature longer estimated-evacuation times and hence the population possesses a weak immediate response capability leaving them more vulnerable to being directly impacted by a tsunami. At a sub-national scale these hotspots were identified and include: the Mentawai islands off the Sumatra coast, various sub-districts on Sumatra and west and east Java. Based on the presented approach a temporal dynamic estimation of casualties and displacements as a function of available response time is obtained for the entire coastal area. As an example, a worst case tsunami scenario for Kuta (Bali results in casualties of 25 000 with an optimal response time (direct evacuation when receiving a tsunami warning and 120 000 for minimal response time (no evacuation. The estimated casualties correspond well to observed/reported values and overall model uncertainty is low with a standard error of 5%.
The results obtained allow for prioritization of intervention measures such as early warning chain, evacuation and contingency planning, awareness and preparedness strategies down to a sub-district level and can be used in tsunami early warning decision support.
The National Data Buoy Center (NDBC) has maintained and operated the National Oceanic and Atmospheric Administration's (NOAA) tsunameter network since 2003. The tsunameters employ the NOAA-developed Deep-ocean Assessment and Reporting of Tsunamis (DART) technology. The technology measures the pressure and temperature every 15 seconds on the ocean floor and transforms them into equivalent water-column height observations. A complex series of subsampled observations are transmitted acoustically in real-time to a moored buoy or marine autonomous vehicle (MAV) at the ocean surface. The surface platform uses its satellite communications to relay the observations to NDBC. NDBC places the observations onto the Global Telecommunication System (GTS) for relay to NOAA's Tsunami Warning Centers (TWC) in Hawai'i and Alaska and to the international community. It takes less than three minutes to speed the observations from the ocean floor to the TWCs. NDBC can retrieve limited amounts of the 15-s measurements from the instrumentation on the ocean floor using the technology's two-way communications. NDBC recovers the full resolution 15-s measurements about every 2 years and forwards the datasets and metadata to the National Geophysical Data Center for permanent archive. Meanwhile, NDBC retains the real-time observations on its website. The type of real-time observation depends on the operating mode of the tsunameter. NDBC provides the observations in a variety of traditional and innovative methods and formats that include descriptors of the operating mode. Datasets, organized by station, are available from the NDBC website as text files and from the NDBC THREDDS server in netCDF format. The website provides alerts and lists of events that allow users to focus on the information relevant for tsunami hazard analysis. In addition, NDBC developed a basic web service to query station information and observations to support the Short-term Inundation Forecasting for Tsunamis (SIFT) model. NDBC and NOAA's Integrated Ocean Observing System have fielded the innovative Sensor Observation Service (SOS) that allows users access to observations by station, or groups of stations that have been organized into Features of Interest, such as the 2011 Honshu Tsunami. The user can elect to receive the SOS observations in several different formats, such as Sensor Web Enablement (SWE) or delimiter-separated values. Recently, NDBC's Coastal and Offshore Buoys provided meteorological observations used in analyzing possible meteotsunamis on the U.S. East Coast. However, many of these observations are some distance away from the tsunameters. In a demonstration project, NDBC has added sensors to a tsunameter's surface buoy and a MAV to support program requirements for meteorological observations. All these observations are available from NDBC's website in text files, netCDF, and SOS. To aid users in obtaining information relevant to their applications, the presentation documents, in detail, the characteristics of the different types of real-time observations and the availability and organization of the resulting datasets at NDBC .
Bouchard, R. H.; O'Neil, K.; Grissom, K.; Garcia, M.; Bernard, L. J.; Kern, K. J.
In the framework of the German Indonesian Tsunami Early Warning System (GITEWS) the assessment of tsunami risk is an essential part of the overall activities. The scientific and technical approach for the tsunami risk assessment has been developed and the results are implemented in the national Indonesian Tsunami Warning Centre and are provided to the national and regional disaster management and spatial planning institutions in Indonesia.
The paper explains the underlyin...
Strunz, G.; Post, J.; Zosseder, K.; Wegscheider, S.; Mu?ck, M.; Riedlinger, T.; Mehl, H.; Dech, S.; Birkmann, J.; Gebert, N.; Harjono, H.; Anwar, H. Z.; Sumaryono; Khomarudin, R. M.; Muhari, A.
The horrific December 26, 2004, Indian Ocean tsunami, which killed over 230,000 people and displaced 1.7 million across 14 countries, stimulated governments of the world into addressing tsunami hazards. Many Indian Ocean nations did not even recognize the word "tsunami," and none had tsunami preparedness programs in place. Ignorance of the natural signs of a tsunami's presence led to inappropriate actions and decisions by nations, population centers, and tourist destinations. The world's resp...
The recent recurrences of mega tsunamis in the Asian region have rekindled concern regarding potential tsunamis that could inflict severe damage to affected coastal facilities and communities. The 11 March 2011 Fukushima tsunami that crippled nuclear power plants in Northern Japan has further raised the level of caution. The recent discovery of petroleum reserves in the coastal water surrounding Malaysia further ignites the concern regarding tsunami hazards to petroleum facilities located along affected coasts. Working in a group, federal government agencies seek to understand the dynamics of tsunami and their impacts under the coordination of the Malaysian National Centre for Tsunami Research, Malaysian Meteorological Department. Knowledge regarding the generation, propagation and runup of tsunami would provide the scientific basis to address safety issues. An in-house tsunami simulation models known as TUNA has been developed by the authors to assess tsunami hazards along affected beaches so that mitigation measures could be put in place. Capacity building on tsunami simulation plays a critical role in the development of tsunami resilience. This paper aims to first provide a simple introduction to tsunami simulation towards the achievement of tsunami simulation capacity building. The paper will also present several scenarios of tsunami dangers along affected Malaysia coastal regions via TUNA simulations to highlight tsunami threats. The choice of tsunami generation parameters reflects the concern following the Fukushima tsunami.
Koh, Hock Lye; Teh, Su Yean; Abas, Mohd Rosaidi Che
tsunami early warning systems in the world can give either one or a combination of estimated tsunami arrival times, heights, or qualitative tsunami forecasts before the tsunami hits near-field coastlines. A future tsunami early warning system should be able to provide a reliable near-field tsunami inundation forecast on high-resolution topography within a short time period. Here we describe a new methodology for near-field tsunami inundation forecasting. In this method, a precomputed tsunami inundation and precomputed tsunami waveform database is required. After information about a tsunami source is estimated, tsunami waveforms at nearshore points can be simulated in real time. A scenario that gives the most similar tsunami waveforms is selected as the site-specific best scenario and the tsunami inundation from that scenario is selected as the tsunami inundation forecast. To test the algorithm, tsunami inundation along the Sanriku Coast is forecasted by using source models for the 2011 Tohoku earthquake estimated from GPS, W phase, or offshore tsunami waveform data. The forecasting algorithm is capable of providing a tsunami inundation forecast that is similar to that obtained by numerical forward modeling but with remarkably smaller CPU time. The time required to forecast tsunami inundation in coastal sites from the Sendai Plain to Miyako City is approximately 3 min after information about the tsunami source is obtained. We found that the tsunami inundation forecasts from the 5 min GPS, 5 min W phase, 10 min W phase fault models, and 35 min tsunami source model are all reliable for tsunami early warning purposes and quantitatively match the observations well, although the latter model gives tsunami forecasts with highest overall accuracy. The required times to obtain tsunami forecast from the above four models are 8 min, 9 min, 14 min, and 39 min after the earthquake, respectively, or in other words 3 min after receiving the source model. This method can be useful in developing future tsunami forecasting systems with a capability of providing tsunami inundation forecasts for locations near the tsunami source area.
Gusman, Aditya Riadi; Tanioka, Yuichiro; MacInnes, Breanyn T.; Tsushima, Hiroaki
Panel 5 focused on tsunami flooding with an emphasis on Probabilistic Tsunami Hazard Analysis (PTHA) as derived from its counterpart, Probabilistic Seismic Hazard Analysis (PSHA) that determines seismic ground-motion hazards. The Panel reviewed current practices in PTHA and determined the viability of extending the analysis to extreme design probabilities (i.e., 10-4 to 10-6). In addition to earthquake sources for tsunamis, PTHA for extreme events necessitates the inclusion of tsunamis generated by submarine landslides, and treatment of the large attendant uncertainty in source characterization and recurrence rates. Tsunamis can be caused by local and distant earthquakes, landslides, volcanism, and asteroid/meteorite impacts. Coastal flooding caused by storm surges and seiches is covered in Panel 7. Tsunamis directly tied to earthquakes, the similarities with (and path forward offered by) the PSHA approach for PTHA, and especially submarine landslide tsunamis were a particular focus of Panel 5.
Geist, Eric; Jones, Henry; McBride, Mark; Fedors, Randy
The December 2004 Indian Ocean tsunami increased global awareness to the destruction hazard posed by earthquakes and tsunamis around the world. The United States government has committed 37.5 million dollars toward the upgrade of earthquake and tsunami monitoring systems in the Caribbean region. Several historical earthquakes have caused considerable damage throughout the Caribbean, many causing tsunamis. The US Geological Survey is using a large part of this money to enhance capabilities for rapid detection and notification of earthquakes in the Caribbean in an attempt to warn the millions living in this area of possible tsunamis. The USGS is working with the Puerto Rico Seismic Network, the Seismological Research Unit at the University of West Indies, eight other host countries, and the National Oceanic and Atmospheric Administration (NOAA). These groups are in the process of installing or upgrading seismic monitoring sites in the earthquake zones of the region. NOAA is also installing four Deep-ocean Assessment and Reporting of Tsunami (DART) buoys in support of a Caribbean-wide tsunami warning system. Planned seismic stations are located in Antigua/Barbuda, Barbados, Cuba (U.S. Naval Base at Guantanamo Bay), the Dominican Republic, Jamaica, Honduras, Panama, Turks and Caicos, and Grenada. Satellite telemetry will transmit data from these sites to NEIC, Golden, CO, where the data will be redistributed to NOAA, the University of Puerto Rico and the University of the West Indies, the IRIS Data Management Center and other agencies. The development of seismic monitoring operations began on January 9, 2006. This will improve seismic monitoring capabilities in the Caribbean and Central America, provide better real time data for global monitoring research and assessment activities, and improve understanding of historical tsunamis and their effects on the Caribbean.
Farwell, J.; Kelly, A.; Mooney, W. D.
Full Text Available In the framework of the German Indonesian Tsunami Early Warning System (GITEWS the assessment of tsunami risk is an essential part of the overall activities. The scientific and technical approach for the tsunami risk assessment has been developed and the results are implemented in the national Indonesian Tsunami Warning Centre and are provided to the national and regional disaster management and spatial planning institutions in Indonesia.
The paper explains the underlying concepts and applied methods and shows some of the results achieved in the GITEWS project (Rudloff et al., 2009. The tsunami risk assessment has been performed at an overview scale at sub-national level covering the coastal areas of southern Sumatra, Java and Bali and also on a detailed scale in three pilot areas. The results are provided as thematic maps and GIS information layers for the national and regional planning institutions. From the analyses key parameters of tsunami risk are derived, which are integrated and stored in the decision support system of the national Indonesian Early Warning Centre. Moreover, technical descriptions and guidelines were elaborated to explain the developed approach, to allow future updates of the results and the further development of the methodologies, and to enable the local authorities to conduct tsunami risk assessment by using their own resources.
It is very difficult to determine and assessment for tsunami hazard. For determining a tsunami risk for NPP site, a development of tsunami hazard is one of the most important. Through the tsunami hazard analysis, a tsunami return period can be determined. For the performing a tsunami hazard analysis, empirical method and numerical method should be needed. Kim et al, already developed tsunami hazard for east coast of Korea for the calculation of tsunami risk of nuclear power plant. In the case of tsunami hazard analysis, a development of tsunami catalog should be performed. In the previous research of Kim et al, the maximum wave height was assumed by the author's decision based on historical record in the annals of Chosun dynasty for evaluating the tsunami catalog. Therefore, in this study, a literature survey was performed for a quantitative measure of historical tsunami record transform to qualitative tsunami wave height for the evaluation of tsunami catalog. In this study, the 1741 tsunami was determined by using a literature review for the evaluation of tsunami hazard. The 1741 tsunami reveals a same tsunami between the historical records in Korea and Japan. The tsunami source of 1741 tsunami was not an earthquake and volcanic. Using the numerical analysis, the wave height of 1741 tsunami can be determined qualitatively.
Kim, Minkyu; Rhee, Hyunme; Choi, Inkil [Korea Atomic Energy Research institute, Daejeon (Korea, Republic of)
It is very difficult to determine and assessment for tsunami hazard. For determining a tsunami risk for NPP site, a development of tsunami hazard is one of the most important. Through the tsunami hazard analysis, a tsunami return period can be determined. For the performing a tsunami hazard analysis, empirical method and numerical method should be needed. Kim et al, already developed tsunami hazard for east coast of Korea for the calculation of tsunami risk of nuclear power plant. In the case of tsunami hazard analysis, a development of tsunami catalog should be performed. In the previous research of Kim et al, the maximum wave height was assumed by the author's decision based on historical record in the annals of Chosun dynasty for evaluating the tsunami catalog. Therefore, in this study, a literature survey was performed for a quantitative measure of historical tsunami record transform to qualitative tsunami wave height for the evaluation of tsunami catalog. In this study, the 1741 tsunami was determined by using a literature review for the evaluation of tsunami hazard. The 1741 tsunami reveals a same tsunami between the historical records in Korea and Japan. The tsunami source of 1741 tsunami was not an earthquake and volcanic. Using the numerical analysis, the wave height of 1741 tsunami can be determined qualitatively
Full Text Available The horrific December 26, 2004, Indian Ocean tsunami, which killed over 230,000 people and displaced 1.7 million across 14 countries, stimulated governments of the world into addressing tsunami hazards. Many Indian Ocean nations did not even recognize the word "tsunami," and none had tsunami preparedness programs in place. Ignorance of the natural signs of a tsunami's presence led to inappropriate actions and decisions by nations, population centers, and tourist destinations. The world's response to this terrible natural disaster was an unprecedented $13.5 billion in international aid, including $5.5 billion from the general public in developed nations. The 2004 tsunami, one of the top 10 deadliest natural disasters the world has recorded, will probably be best remembered for the global outpouring of help to the innocent victims of this tragedy.
The results of a pilot study to assess the risk from tsunamis for the Seaside-Gearhart, Oregon region will be presented. To determine the risk from tsunamis, it is first necessary to establish the hazard or probability that a tsunami of a particular magnitude will occur within a certain period of time. Tsunami inundation maps that provide 100-year and 500-year probabilistic tsunami wave height contours for the Seaside-Gearhart, Oregon, region were developed as part of an interagency Tsunami Pilot Study(1). These maps provided the probability of the tsunami hazard. The next step in determining risk is to determine the vulnerability or degree of loss resulting from the occurrence of tsunamis due to exposure and fragility. The tsunami vulnerability assessment methodology used in this study was developed by M. Papathoma and others(2). This model incorporates multiple factors (e.g. parameters related to the natural and built environments and socio-demographics) that contribute to tsunami vulnerability. Data provided with FEMA's HAZUS loss estimation software and Clatsop County, Oregon, tax assessment data were used as input to the model. The results, presented within a geographic information system, reveal the percentage of buildings in need of reinforcement and the population density in different inundation depth zones. These results can be used for tsunami mitigation, local planning, and for determining post-tsunami disaster response by emergency services. (1)Tsunami Pilot Study Working Group, Seaside, Oregon Tsunami Pilot Study--Modernization of FEMA Flood Hazard Maps, Joint NOAA/USGS/FEMA Special Report, U.S. National Oceanic and Atmospheric Administration, U.S. Geological Survey, U.S. Federal Emergency Management Agency, 2006, Final Draft. (2)Papathoma, M., D. Dominey-Howes, D.,Y. Zong, D. Smith, Assessing Tsunami Vulnerability, an example from Herakleio, Crete, Natural Hazards and Earth System Sciences, Vol. 3, 2003, p. 377-389.
Dunbar, P. K.; Dominey-Howes, D.; Varner, J.
We doubt the relevance of soliton theory to the modelling of tsunamis, and present a case in support of an alternative view. Although the shallow-water equations do provide, we believe, an appropriate basis for this phenomenon, an asymptotic analysis of the solution for realistic variable depths, and for suitable background flows, is essential for a complete understanding of this phenomenon. In particular we explain how a number of tsunami waves can arrive at a shoreline. (letter to the editor)
The coasts of Turkey have been hit by tsunamis in the past. The first national earthquake-tsunami catalogues were compiled in the early 1980s while the most up-to-date tsunami catalogues are mainly the products of recent European projects. The EU projects GITEC and GITEC-TWO (Genesis and Impact of Tsunamis on the European Coasts) and TRANSFER (Tsunami Risk ANd Strategies For the European Region) have added important contributions in establishing and developing unified criteria for tsunami par...
Altinok, Y.; Alpar, B.; O?zer, N.; Aykurt, H.
The forecasting models displayed in this website are from NOAA Center for Tsunami Research featuring the Honshu, Japan tsunami. Forecast results, showing qualitative and quantitative information about the tsunami, including tsunami wave interaction with ocean floor bathymetric features, and neighboring coastlines are available for educators and students. Also included are interactive maps depicting model and sea level data comparison plots, global maximum wave amplitude and tsunami propagation animations.
On December 26, 2004, a disastrous tsunami struck many parts of South Asia. The scope of this disaster has resulted in an outpouring of aid throughout the world and brought attention to the science of tsunamis. "Tsunami" means "harbor wave" in Japanese, and the Japanese have a long history of tsunamis. The word "tsunami" brings to mind one…
Mogil, H. Michael
Tsunamis are long waves generated by impulsive disturbances of the seafloor or coastal topography caused by earthquakes, submarine/subaerial mass failures. They evolve substantially through three dimensional - 2 spatial+1 temporal - spreading as the initial surface deformation propagates. This is referred to as its directivity and focusing. A directivity function was first defined by Ben-Menahem (1961, Bull. Seismol. Soc. Am. 51, 401-435) using the source length and the rupture velocity. Okal (2003, Pure Appl. Geophys. 160, 2189-2221) discussed the details of the analysis of Ben-Menahem (1961) and demonstrated the distinct difference between the directivity patterns of landslide and earthquake generated tsunamis. Marchuk and Titov (1989, Proc. IUGG/IOC International Tsunami Symposium, July 31 - August 3, 1989, Novosibirsk, USSR. p.11-17) described the process of tsunami focusing for a rectangular initial deformation combining positive and negative surface displacements. They showed the existence of a focusing point where abnormal tsunami wave height can be registered. Here, first, we describe and quantify numerically tsunami focusing processes for a combined positive and negative - N-wave type - strip source representing the 17 July 1998 Papua New Guinea and 17 July 2006 Java events. Specifically, considering field observations and tsunami focusing, we propose a source mechanism for the 17 July 2006 Java event. Then, we introduce a new analytical solution for a strip source propagating over a flat bottom using the linear shallow-water wave equation. The analytical solution of Carrier and Yeh (2005, Computer Modeling In Engineering & Sciences, 10(2), 113-121) appears to have two drawbacks. One, the solution involves singular complete elliptic integral of the first kind which results in a self-similar approximate solution for the far-field at large times. Two, only the propagation of Gaussian shaped finite-crest wave profiles can be modeled. Our solution is not only exact but also more general and allows the use of realistic initial waveform such as N-waves defined by Tadepalli and Synolakis (1994, Proc. R. Soc. Lond. A 445, 99-112). We explore parametric dependence of the focusing height and distance on the initial wave parameters through the analytical solution.
Spillane, M. C.; Titov, V. V.; Moore, C. W.; Aydin, B.; Kanoglu, U.; Synolakis, C. E.
Strongest earthquake of December 26, 2004 generated catastrophic tsunami in Indian Ocean. This shows that, in spite of recent technology progress, population at coastal zone is not protected against tsunami hazard. Here, we address the problem of tsunami risks mitigation. Note that prediction of tsunami wave parameters at certain locations should be made as early as possible to provide enough time for evacuation. Therefore, fast tsunami propagation code that can calculate tsunami evolution from estimated model source becomes critical for timely evacuation decision for many coastal communities in case of a strong tsunami. Numerical simulation of tsunami wave is very important task for risk evaluation, assessment and mitigation. Here we discuss a part of MOST  (Method of Splitting Tsunami) software package, which has been accepted by the USA National Ocean and Atmosphere Administration as the basic tool to calculate tsunami wave propagation and evaluation of inundation parameters. Our main objectives are speed up the sequential program, and adaptation of this program for shared memory systems (OpenMP) and CELL architecture. For caring out this research we use SMP server and a system build on IBM CELL BE CPU. We perform optimization of the existing parallel and sequential code for the task of tsunami wave propagation modeling as well as an adaptation of this code for systems based on CELL BE processors. We achieve 10 times performance gain for SMP system using OpenMP technology compared to sequential application and about 50 times performance gain for single CELL BE CPU. Thus, we show that significant acceleration for this program is possible. The results also show that non-standard equipment for HPC like Sony PlayStation3 could be used for solving this kind of problems. 1. Chawla, A., J. Borrero and V. Titov, (2008), Evaluating wave propagation and inundation characteristics of the MOST tsunami model over a complex 3D beach, Advances in Coastal and Ocean Engineering, v. 10, 261-267 (in press).
Lavrentiev, M., Jr.; Romanenko, A.; Titov, V.; Vazhenin, A.
Probabilistic hazard assessments are a fundamental tool for assessing the threats posed by hazards to communities and are important for underpinning evidence-based decision-making regarding risk mitigation activities. Indonesia has been the focus of intense tsunami risk mitigation efforts following the 2004 Indian Ocean tsunami, but this has been largely concentrated on the Sunda Arc with little attention to other tsunami prone areas of the country such as eastern Indonesia. We present the first nationally consistent probabilistic tsunami hazard assessment (PTHA) for Indonesia. This assessment produces time-independent forecasts of tsunami hazards at the coast using data from tsunami generated by local, regional and distant earthquake sources. The methodology is based on the established monte carlo approach to probabilistic seismic hazard assessment (PSHA) and has been adapted to tsunami. We account for sources of epistemic and aleatory uncertainty in the analysis through the use of logic trees and sampling probability density functions. For short return periods (100 years) the highest tsunami hazard is the west coast of Sumatra, south coast of Java and the north coast of Papua. For longer return periods (500-2500 years), the tsunami hazard is highest along the Sunda Arc, reflecting the larger maximum magnitudes. The annual probability of experiencing a tsunami with a height of > 0.5 m at the coast is greater than 10% for Sumatra, Java, the Sunda islands (Bali, Lombok, Flores, Sumba) and north Papua. The annual probability of experiencing a tsunami with a height of > 3.0 m, which would cause significant inundation and fatalities, is 1-10% in Sumatra, Java, Bali, Lombok and north Papua, and 0.1-1% for north Sulawesi, Seram and Flores. The results of this national-scale hazard assessment provide evidence for disaster managers to prioritise regions for risk mitigation activities and/or more detailed hazard or risk assessment.
Horspool, N.; Pranantyo, I.; Griffin, J.; Latief, H.; Natawidjaja, D. H.; Kongko, W.; Cipta, A.; Bustaman, B.; Anugrah, S. D.; Thio, H. K.
Web companion to an episode of the PBS/WNET television series "Savage Earth" devoted to tsunamis. The homepage article provides a brief overview of the mechanism that creates tsunamis, the enormous energy they release, and the role of plate tectonics in earthquake and tsunami generation. Sidebar pages discuss tsunami monitoring and advance warning, and geologic investigations that reveal evidence of destructive tsunamis in the past. There is also an animation that shows how an earthquake at a subduction zone can cause the sea floor to snap upward abruptly, displacing water and generating a tsunami, and a video interview with a survivor of the 1946 tsunami that struck the Hawaiian Islands.
In this paper we investigate important dynamics defining tsunami enhancement in the coastal regions and related to interaction with tides. Observations and computations of the Indian Ocean Tsunami usually show amplifications of the tsunami in the near-shore regions due to water shoaling. Additionally, numerous observations depicted quite long ringing of tsunami oscillations in the coastal regions, suggesting either local resonance or the local trapping of the tsunami energy. In the real ocean...
Zygmunt Kowalik; Tatiana Proshutinsky; Andrey Proshutinsky
1. Tsunamis - Introduction - Definition of phenomenon - basic properties of the waves Propagation and dispersion Interaction with coasts - Geological and societal effects Origin of tsunamis - natural sources Scientific activities in connection with tsunamis. Ideas about simulations 2. Tsunami generation - The earthquake source - conventional theory The earthquake source - normal mode theory The landslide source Near-field observation - The Plafker index Far-field observation - Directivity 3. Tsunami warning - General ideas - History of efforts Mantle magnitudes and TREMOR algorithms The challenge of "tsunami earthquakes" Energy-moment ratios and slow earthquakes Implementation and the components of warning centers 4. Tsunami surveys - Principles and methodologies Fifteen years of field surveys and related milestones. Reconstructing historical tsunamis: eyewitnesses and geological evidence 5. Lessons from the 2004 Indonesian tsunami - Lessons in seismology Lessons in Geology The new technologies Lessons in civ...
Full Text Available The qualitative characteristics of accounting information presented by financial-accounting reports represent a concept which was subsequently introduced in the national legal accounting framework and, as a rule, the national conceptual frameworks represent the documents by means of which these quality criteria are established. At a worldwide level, there are more international or national organisms that have an important role in the elaboration of accounting standards in general and more specifically in the formulation of qualitative characteristics of financial reporting. We find two important ones among them, and these are: International Accounting Standards Board, which creates and promotes International Financial Reporting Standards (IFRS, and Financial Accounting Standards Board, which elaborates Generally Accepted Accounting Principles (US GAAP. However, at the level of each country a standardizing authority decides the rules for producing the financial reports and the qualitative characteristics that must be respected by the information contained in these documents. In this context, this paper aims to present a few general considerations concerning the treatment of the qualitative characteristics of the financial-accounting information in different accounting systems, such as the American one, or the British, French, German, Romanian ones, with insistence on the international approach to qualitative characteristics.
Ionela Cristina Breahna Pravat
Full Text Available Inspired by recent discussion on how Serbian media influenced allegedly indifferent reaction of the public to the aftermath of tsunami, this paper examines the role of electronic media in Serbia, television in particular, in regard to their function as a central communication channel for acquiring knowledge about world surroundings. With a premise of having cultural and discursive power, Dnevnik, the central news program of the Serbian public broadcaster, is taken as a paradigmatic media text for analysis in order to examine ways in which global affairs and phenomena are portrayed and structured in television representation of reality. It is suggested that it is fair to conclude that world affairs are marginalized within the representational frame of news broadcasts, and that the media discourse could be depicted as dominantly introverted when it comes to global flow of information and cultural meanings, which is significant regarding cultural perception of world realities among Serbian audiences.
... Landslides Tornadoes Tsunamis Volcanoes Wildfires Winter Weather Tsunamis: Water Quality Language: English Español (Spanish) Share Compartir A ... about testing should be directed to local authorities. Water for Drinking, Cooking, and Personal Hygiene Safe water ...
Purpose: To identify the factors that determine the attractiveness of radiography as a career choice and of the National Health Service (NHS) as an employer to potential recruits and returners. Methods: Individual and group interviews were conducted in the East Midlands region to explore participants' perceptions of the attractiveness of the NHS as an employer to potential radiography staff. Interviews were conducted with school pupils, radiography students, mature students, radiography assistants, agency radiographers and independent sector radiographers. Results: Eighty-eight individuals participated in the qualitative stage of the study. Analysis of the interview transcripts indicated that radiography as a career choice is perceived as boring and routine, involving high workloads and little recognition from the general public. Working with patients is the source of considerable job satisfaction but is offset by staff shortages, lack of flexibility over working hours and a lack of consideration of family commitments in the NHS. Financial costs are highlighted as dissuading many participants from considering a career as a radiographer in the NHS or returning to work for the NHS. Greater use of open days in conjunction with more advertising of the profession is suggested as tactics to improve recruitment. Conclusions: The provision of more flexible working hours, greater consideration of family commitments and increased financial support for training are necessary to improve the attractiveness of a radiography career. NHS Human Resource Managers should consider these findings concerning the applicant and returner pools when developing strategies to address the current shortfall of radiographers.
Coombs, C.R. E-mail: firstname.lastname@example.org; Park, J.R.; Loan-Clarke, J.; Arnold, J.; Preston, D.; Wilkinson, A.J
Purpose: To identify the factors that determine the attractiveness of radiography as a career choice and of the National Health Service (NHS) as an employer to potential recruits and returners. Methods: Individual and group interviews were conducted in the East Midlands region to explore participants' perceptions of the attractiveness of the NHS as an employer to potential radiography staff. Interviews were conducted with school pupils, radiography students, mature students, radiography assistants, agency radiographers and independent sector radiographers. Results: Eighty-eight individuals participated in the qualitative stage of the study. Analysis of the interview transcripts indicated that radiography as a career choice is perceived as boring and routine, involving high workloads and little recognition from the general public. Working with patients is the source of considerable job satisfaction but is offset by staff shortages, lack of flexibility over working hours and a lack of consideration of family commitments in the NHS. Financial costs are highlighted as dissuading many participants from considering a career as a radiographer in the NHS or returning to work for the NHS. Greater use of open days in conjunction with more advertising of the profession is suggested as tactics to improve recruitment. Conclusions: The provision of more flexible working hours, greater consideration of family commitments and increased financial support for training are necessary to ial support for training are necessary to improve the attractiveness of a radiography career. NHS Human Resource Managers should consider these findings concerning the applicant and returner pools when developing strategies to address the current shortfall of radiographers
Seismic hazard analysis has reached a level of maturity in China. Such work has contributed significantly towards improvements of the national infrastructure in effecting programs of disaster preparedness and mitigation. However, the work on tsunami risk assessment is still in a preliminary stage. The present study proposes a deterministic method of tsunami hazard analysis based on coastal bathymetry and morphology, as well as on mathematical simulations, and evaluates the potential tsunami r...
Yefei Ren; Ruizhi Wen; Baofeng Zhou; Dacheng Shi
The study of tsunamis has been shifting away from theoretical modeling of tsunami source, wave propagation and runup toward multidisciplinary investigations, with an emphasis on field studies. This collection of papers highlights the many approaches being utilized to study landslides and tsunamis.
Keating, Barbara H., (Edited By); Waythomas, Christopher F.; Dawson, Alastair G.
The North East Atlantic, Mediterranean and Adjacent Seas (called NEAM by IOC-UNESCO) is known to be exposed to tsunamis and, like other regions of the world, faces increasing levels of risk due to i) the continuous development of coastal areas with critical infrastructures and accumulated values, and ii) the year-round presence of millions of tourists. In recent years, European researchers have greatly advanced knowledge of tsunami hazards and implementation of operational infrastructures, such as the creation of a regional system of candidate tsunami watch providers (CTWP) and national tsunami warning centers (NTWC). However, significant gaps remain and intensified efforts are needed. The ASTARTE (Assessment STrategy And Risk for Tsunami in Europe) is a three-year long EU-funded project, started in November 2013, that aims to develop a comprehensive strategy to mitigate tsunami impact in the NEAM region. To achieve this goal, an interdisciplinary consortium has been assembled. It includes all NEAM CTWPs and expert institutions across Europe and worldwide. ASTARTE will improve i) the basic knowledge on tsunami generation and recurrence with novel empirical data and new statistical analyses for assessing long-term recurrence and hazards of large events in sensitive areas within NEAM, ii) numerical techniques for tsunami simulation focusing on real-time codes, novel statistical emulation approaches, and experiments on damage analysis, and iii) methods for the assessment of hazard, vulnerability, and risk. ASTARTE will also provide i) guidelines for tsunami Eurocodes, ii) better forecasting and warning tools for CTWPs and NTWCs, and iii) guidelines for decision makers to increase the sustainability and resilience of coastal communities. In summary, ASTARTE will develop basic scientific and technical elements allowing for a significant enhancement of the Tsunami Warning System in the NEAM region in terms of monitoring, early warning,forecast, and resilience, with specific implementation in 9 tsunami test sites. Overall, this will lead to the goal of the European/NEAM Horizon 2020 strategy: to foster tsunami resilient communities. www.astarte-project.eu This work is funded by project ASTARTE - Assessment, STrategy And Risk Reduction for Tsunamis in Europe. Grant 603839, 7th FP (ENV.2013.6.4-3 ENV.2013.6.4-3).
Baptista, Maria Ana; Yalciner, Ahmet; Canals, Miquel; Behrens, Joern; Fuhrman, David; Gonzalez, Mauricio; Harbitz, Carl; Kanoglu, Utku; Karanci, Nurai; Lavigne, Franck; Lorito, Stefano; Meghraoui, Mustafa; Melis, Nikolaos S.; Necmioglu, Ocal; Papadopoulos, Gerassimos A.; Rudloff, Alexander; Schindele, François; Terrinha, Pedro; Tinti, Stefano
The California tsunami program in cooperation with NOAA and FEMA has begun implementing a plan to increase awareness of tsunami generated hazards to the maritime community (both ships and harbor infrastructure) through the development of in-harbor hazard maps, offshore safety zones for boater evacuation, and associated guidance for harbors and marinas before, during and following tsunamis. The hope is that the maritime guidance and associated education and outreach program will help save lives and reduce exposure of damage to boats and harbor infrastructure. An important step in this process is to understand the causative mechanism for damage in ports and harbors, and then ensure that the models used to generate hazard maps are able to accurately simulate these processes. Findings will be used to develop maps, guidance documents, and consistent policy recommendations for emergency managers and port authorities and provide information critical to real-time decisions required when responding to tsunami alert notifications. Basin resonance and geometric amplification are two reasonably well understood mechanisms for local magnification of tsunami impact in harbors, and are generally the mechanisms investigated when estimating the tsunami hazard potential in a port or harbor. On the other hand, our understanding of and predictive ability for currents is lacking. When a free surface flow is forced through a geometric constriction, it is readily expected that the enhanced potential gradient will drive strong, possibly unstable currents and the associated turbulent coherent structures such as "jets" and "whirlpools"; a simple example would be tidal flow through an inlet channel. However, these fundamentals have not been quantitatively connected with respect to understanding tsunami hazards in ports and harbors. A plausible explanation for this oversight is the observation that these features are turbulent phenomena with spatial and temporal scales much smaller than that of a typical tsunami. The ability to model and then validate these currentsdissect them has only recently become available through the evaluation of dozens of eyewitness accounts and hundreds of videos.developed. In this presentation, we will present ongoing work related to the application of such models to quantify the maritime tsunami hazard in select ports and harbors in California. The development of current-based tsunami hazard maps and safe-offshore-depth delineations will be discussed. We will also present an overview of the challenges in modeling tsunami currents, including capture of turbulent dynamics, coupling with tides, and issues with long-duration simulations. This work in California will form the basis for tsunami hazard reduction for all U.S. maritime communities through the National Tsunami Hazard Mitigation Program.
Lynett, P. J.; Borrero, J. C.; Wilson, R. I.; Miller, K. M.
Full Text Available Post-tsunami field investigations are an essential component in improving our understanding of tsunamis and in developing the tools and programs necessary to mitigate their effects. A destructive tsunami can attract a large number of international, national, and local tsunami professionals interested in conducting post-tsunami science surveys to investigate and document its scientific, economic, and social impact on affected coasts and communities. Science data collected immediately after a damaging tsunami are important for government decision makers. In the short term, these data help to better organize and deploy often-limited resources to the most critical areas needing response. In the long term, these data are used for recovery planning that will mitigate the losses of the next tsunami. Without a coordination plan that is integrated into government emergency response operations, perishable data may prove to be logistically difficult to gather before erosion or bulldozers eliminate the evidence, and in all likelihood, the operations could interfere and conflict with emergency activities. Additionally, during catastrophic tsunamis, affected areas and local jurisdictions may also be simultaneously overwhelmed by many government agencies, nongovernment organizations, and the media all demanding information and/or access, thus making collection of useful data even more challenging unless a coordination and information sharing plan is already in place.
Full Text Available Abstract Background Perinatal death is a devastating experience for the mother and of concern in clinical practice. Regular perinatal audit may identify suboptimal care related to perinatal deaths and thus appropriate measures for its reduction. The aim of this study was to perform a qualitative perinatal audit of intrapartum and early neonatal deaths and propose means of reducing the perinatal mortality rate (PMR. Methods From 1st August, 2007 to 31st December, 2007 we conducted an audit of perinatal deaths (n = 133 with birth weight 1500 g or more at Muhimbili National Hospital (MNH. The audit was done by three obstetricians, two external and one internal auditors. Each auditor independently evaluated the cases narratives. Suboptimal factors were identified in the antepartum, intrapartum and early neonatal period and classified into three levels of delay (community, infrastructure and health care. The contribution of each suboptimal factor to adverse perinatal outcome was identified and the case graded according to possible avoidability. Degree of agreement between auditors was assessed by the kappa coefficient. Results The PMR was 92 per 1000 total births. Suboptimal factors were identified in 80% of audited cases and half of suboptimal factors were found to be the likely cause of adverse perinatal outcome and were preventable. Poor foetal heart monitoring during labour was indirectly associated with over 40% of perinatal death. There was a poor to fair agreement between external and internal auditors. Conclusion There are significant areas of care that need improvement. Poor monitoring during labour was a major cause of avoidable perinatal mortality. This type of audit was a good starting point for quality assurance at MNH. Regular perinatal audits to identify avoidable causes of perinatal deaths with feed back to the staff may be a useful strategy to reduce perinatal mortality.
Thomas Angela N
It is the mission of the California Tsunami Program to ensure public safety by protecting lives and property before, during, and after a potentially destructive or damaging tsunami. In order to achieve this goal, the state has sought first to use finite funding resources to identify and quantify the tsunami hazard using the best available scientific expertise, modeling, data, mapping, and methods at its disposal. Secondly, it has been vital to accurately inform the emergency response community of the nature of the threat by defining inundation zones prior to a tsunami event and leveraging technical expertise during ongoing tsunami alert notifications (specifically incoming wave heights, arrival times, and the dangers of strong currents). State scientists and emergency managers have been able to learn and apply both scientific and emergency response lessons from recent, distant-source tsunamis affecting coastal California (from Samoa in 2009, Chile in 2010, and Japan in 2011). Emergency managers must understand and plan in advance for specific actions and protocols for each alert notification level provided by the NOAA/NWS West Coast/Alaska Tsunami Warning Center. Finally the state program has provided education and outreach information via a multitude of delivery methods, activities, and end products while keeping the message simple, consistent, and focused. The goal is a culture of preparedness and understanding of what to do in the face of a tsunami by residents, visitors, and responsible government officials. We provide an update of results and findings made by the state program with support of the National Tsunami Hazard Mitigation Program through important collaboration with other U.S. States, Territories and agencies. In 2009 the California Emergency Management Agency (CalEMA) and the California Geological Survey (CGS) completed tsunami inundation modeling and mapping for all low-lying, populated coastal areas of California to assist local jurisdictions on the coast in the identification of areas possible to be inundated in a tsunami. "Tsunami Inundation Maps for Emergency Planning" have provided the basis for some of the following preparedness, planning, and education activities in California: Improved evacuation and emergency response plans; Production of multi-language brochures: statewide, community, and boating; Development and support of tsunami scenario-driven exercises and drills; Development of workshops to educate both emergency managers and public; and Establishment of a comprehensive information website www.tsunami.ca.gov; and a preparedness website myhazards.calema.ca.gov. In addition, the California Tsunami Program has a number of initiatives underway through existing work plans to continue to apply scientifically vetted information toward comprehensive public understanding of the threat from future tsunamis to constituents on the coast. These include projects to: Complete tsunami land-use planning maps for California communities, Develop in-harbor tsunami hazard maps statewide, Complete modeling of offshore safety zones for the maritime community, Complete preliminary tsunami risk analysis for state utilizing new HAZUS tsunami module and probabilistic analysis results, and Develop a post-tsunami recovery and resiliency plan for the state.
Miller, K. M.; Wilson, R. I.
Rapid estimation of the tsunami waveheight after a large earthquake can significantly aid in disaster recovery efforts, planning of post-tsunami surveys and even early warning for more distant regions. We are exploring methods for refining these estimates by addressing variability due to uncertainties in the source parameters. After the Samoa earthquake, we used the solution from the near real-time Research CMT system at the National Earthquake Information Center to compute the tsunami wavefield. Given the close proximity to Samoa and American Samoa, details of the rupture geometry are very important for the character of the tsunami wavefield and we computed tsunami waveforms for several different geometries that are consistent with the rCMT solution. We will evaluate these results by comparing them with observed runups and explore ways to express the uncertainties in the simulated runup maps. We will also evaluate other real-time source estimates for use in rapid tsunami impact simulation.
Thio, H. K.; Polet, J.
Full Text Available In this paper we investigate important dynamics defining tsunami enhancement in the coastal regions and related to interaction with tides. Observations and computations of the Indian Ocean Tsunami usually show amplifications of the tsunami in the near-shore regions due to water shoaling. Additionally, numerous observations depicted quite long ringing of tsunami oscillations in the coastal regions, suggesting either local resonance or the local trapping of the tsunami energy. In the real ocean, the short-period tsunami wave rides on the longer-period tides. The question is whether these two waves can be superposed linearly for the purpose of determining the resulting sea surface height (SSH or rather in the shallow water they interact nonlinearly, enhancing/reducing the total sea level and currents. Since the near–shore bathymetry is important for the run-up computation, Weisz and Winter (2005 demonstrated that the changes of depth caused by tides should not be neglected in tsunami run-up considerations. On the other hand, we hypothesize that much more significant effect of the tsunami-tide interaction should be observed through the tidal and tsunami currents. In order to test this hypothesis we apply a simple set of 1-D equations of motion and continuity to demonstrate the dynamics of tsunami and tide interaction in the vicinity of the shelf break for two coastal domains: shallow waters of an elongated inlet and narrow shelf typical for deep waters of the Gulf of Alaska.
COMMENT ON: TSUNAMIS AND TSUNAMI-LIKE WAVES OF THE EASTERN UNITED STATES BY PATRICIA A. LOCKRIDGE, LOWELL S. WHITESIDE AND JAMES F. LANDER WITH RESPECT TO THE NOVEMBER 18, 1929 EARTHQUAKE AND ITS TSUNAMI
Full Text Available This most valuable compilation by Patricia Lockridge et al. (2002 covers a wide range of tsunamis and tsunami-like events ranging from marine tectonic, volcanic, and landslide tsunamis to possible meteorologic tsunami-like events. Lockridge et al.'s (2002 massive text table (pp. 124-141 entitled "Description of Events" covers events from 1668 to 1992. The 2002 paper in Science of Tsunami Hazards was clearly intended to be an update of, an extension to, and a sequel to, the first east coast and Caribbean tsunami compilations contained in Lander and Lockridge's 1989 National Geophysical Data Center volume United States Tsunamis (including United States Possessions 1690-1988.The Lockridge et al. (2002 compilation contains a small error with respect to the 1929 "Grand Banks" Earthquake and Tsunami of which I may be cause in part. In addition the tsunami histories of oceans without a tsunami warning system will be now receiving much closer attention, including historic events in the Atlantic Ocean given the events of December 26, 2004 and March 18, 2005 in the Indian Ocean; both the Atlantic and the Indian Oceans have no tsunami warning system and have an incomplete tsunami history.
On the basis of time series of the available Google Earth satellite images, dynamic changes of coastal morphology due to the 2011 Tohoku tsunami attack and the subsequent recovery process in five representative coasts were investigated with respect to both qualitative and quantitative analyses, including the Rikuzentakata coast, the Nanakita coast, the Akaiko coast, the Minamisoma coast and the Kido coast from the north to south along the Japanese Pacific coast. After the tsunami event, beach...
Tsunamis are a constant threat to the coasts of our world. Although tsunamis are infrequent along the West coast of the United States, it is possible and necessary to prepare for potential tsunami hazards to minimize loss of life and property. Community awareness programs are important, as they strive to create an informed society by providing education and training. The Marin coast could be struck by a tsunami. Whether you live in Marin County, visit the beaches, or rent or own a home near the coast, it is vital to understand the tsunami threat and take preparation seriously. Marin Tsunami tells the story of what several West Marin communities are doing to be prepared. This video was produced by the US Geological Survey (USGS) in cooperation with the Marin Office of Emergency Services.
Filmed and edited by: Loeffler, Kurt; Gesell, Justine
Cuba as neo tectonics structure in the southern of the North American plate had three tsunamis. One of them [local] occurred in the Central-Northern region [1931.10.01, Nortecubana fault], the other was a tele tsunami [1755.11.01, in the SW of the Iberian Peninsula] that hit the Bay of Santiago de Cuba, and the third took place at 1867.11.18, by the regional source of Virgin Islands, which produced waves in the Eastern Cuban region. This tsunami originated to the NE of Puerto Rico in 1918.10.11, with another earthquake of equal magnitude and at similar coordinates, produced a tsunami that did not affect Cuba. Information on the influence of regional tsunami in 1946.08.08 of the NE of the Dominican Republic [Matanzas] in Northwestern Cuba [beaches Guanabo-Baracoa] is contrary to expectations with the waves propagation. The local event of 1939.08.15 attributed to Central- Northern Cuba [Cayo Frances with M = 8.1] does not correspond at all with the maximum magnitude of earthquakes in this region and the potential of the Nortecubana fault. Tsunamis attributed to events such as 1766.06.11 and 1932.02.03 in the Santiago de Cuba Bay are not reflected in the original documents from experts and eyewitnesses. Tsunamis from Jamaica have not affected the coasts of Cuba, despite its proximity. There is no influence in Cuba of tsunamigenic sources of the southern and western parts of the Caribbean, or the Gulf of Mexico. Set out the doubts as to the influence of tsunamis from Haiti and Dominican Republic at Guantanamo Bay which is closer to and on the same latitude, and spatial orientation than the counterpart of Santiago de Cuba, that had impact. The number of fatalities by authors in the Caribbean is different and contradictory. (Author) 76 refs.
Cotilla Rodriguez, M. O.
This data tip describes the science behind the tsunamis caused by the great earthquake of December 26, 2004, which caused catastrophic damage and loss of life throughout the Indian Ocean basin. The discussion centers on how tsunamis are generated and how great quakes and resulting tsunamis occur at subducting plate boundaries. Links to more detailed information are embedded in the text. An exercise is included in which students plot the locations of cities around the Indian Ocean basin on a map of tsunami travel times. Discussion questions and links to additional information are also provided.
Tsunami Strike! Caribbean Edition offers an interactive learning experience in which learners take on the role of a journalist writing an article for a news magazine. Sixteen multimedia lessons on tsunami science, safety, and history are interwoven within the learning scenario as resources for the article. The material is aimed at middle school and high school students (ages 13-17) but will be useful to a broader audience wishing to learn more about tsunamis in general, and in particular about tsunami risks in the Caribbean.
Probabilistic hazard assessments are a fundamental tool for assessing the threats posed by hazards to communities and are important for underpinning evidence based decision making on risk mitigation activities. Indonesia has been the focus of intense tsunami risk mitigation efforts following the 2004 Indian Ocean Tsunami, but this has been largely concentrated on the Sunda Arc, with little attention to other tsunami prone areas of the country such as eastern Indonesia. We present the first nationally consistent Probabilistic Tsunami Hazard Assessment (PTHA) for Indonesia. This assessment produces time independent forecasts of tsunami hazard at the coast from tsunami generated by local, regional and distant earthquake sources. The methodology is based on the established monte-carlo approach to probabilistic seismic hazard assessment (PSHA) and has been adapted to tsunami. We account for sources of epistemic and aleatory uncertainty in the analysis through the use of logic trees and through sampling probability density functions. For short return periods (100 years) the highest tsunami hazard is the west coast of Sumatra, south coast of Java and the north coast of Papua. For longer return periods (500-2500 years), the tsunami hazard is highest along the Sunda Arc, reflecting larger maximum magnitudes along the Sunda Arc. The annual probability of experiencing a tsunami with a height at the coast of > 0.5 m is greater than 10% for Sumatra, Java, the Sunda Islands (Bali, Lombok, Flores, Sumba) and north Papua. The annual probability of experiencing a tsunami with a height of >3.0 m, which would cause significant inundation and fatalities, is 1-10% in Sumatra, Java, Bali, Lombok and north Papua, and 0.1-1% for north Sulawesi, Seram and Flores. The results of this national scale hazard assessment provide evidence for disaster managers to prioritise regions for risk mitigation activities and/or more detailed hazard or risk assessment.
Horspool, N.; Pranantyo, I.; Griffin, J.; Latief, H.; Natawidjaja, D. H.; Kongko, W.; Cipta, A.; Bustaman, B.; Anugrah, S. D.; Thio, H. K.
The Caribbean and Adjacent Regions has a long history of tsunamis and earthquakes. Over the past 500 years, more than 75 tsunamis have been documented in the region by the NOAA National Geophysical Data Center. Just since 1842, 3446 lives have been lost to tsunamis; this is more than in the Northeastern Pacific for the same time period. With a population of almost 160 million, over 40 million visitors a year and a heavy concentration of residents, tourists, businesses and critical infrastructure along its shores (especially in the northern and eastern Caribbean), the risk to lives and livelihoods is greater than ever before. The only way to survive a tsunami is to get out of harm's way before the waves strike. In the Caribbean given the relatively short distances from faults, potential submarine landslides and volcanoes to some of the coastlines, the tsunamis are likely to be short fused, so it is imperative that tsunami warnings be issued extremely quickly and people be educated on how to recognize and respond. Nevertheless, given that tsunamis occur infrequently as compared with hurricanes, it is a challenge for them to receive the priority they require in order to save lives when the next one strikes the region. Close cooperation among countries and territories is required for warning, but also for education and public awareness. Geographical vicinity and spoken languages need to be factored in when developing tsunami preparedness in the Caribbean, to make sure citizens receive a clear, reliable and sound science based message about the hazard and the risk. In 2006, in the wake of the Indian Ocean tsunami and after advocating without success for a Caribbean Tsunami Warning System since the mid 90's, the Intergovernmental Oceanographic Commission of UNESCO established the Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS). Its purpose is to advance an end to end tsunami warning system that serves regionally and delivers locally, saving lives and livelihoods, not only from tsunamis, but all coastal hazards. Through this and other platforms, physical and social scientists, emergency managers and elected officials have been working together via different mechanisms. Community based recognition programs, like the TsunamiReadyTM Program, regional tsunami exercises, sub-regional public education activities such as the Tsunami Smart campaigns, internet technologies, social media, meetings and conferences, identification of local and national champions, capitalization of news breaking tsunamis and earthquakes, economic resources for equipment and training have all been key to developing a tsunami safer Caribbean. Given these efforts, according to a 2013 survey, 93% of the countries covered by CARIBE EWS have tsunami response protocols in place, although much more work is required. In 2010 the US National Weather Service established the Caribbean Tsunami Warning Program as the first step towards a Caribbean Tsunami Warning Center in the region. In 2013 the Caribbean Tsunami Information Center was established in Barbados. Both these institutions which serve the region play a key role for promoting both the warning and educational components of the warning system.
von Hillebrandt-Andrade, C.; Aliaga, B.; Edwards, S.
The death total in a major Cascadia Subduction Zone (CSZ) tsunami may be comparable to the Tohoku tsunami - tens of thousands. To date, tsunami risk reduction activities have been almost exclusively hazard mapping and evacuation planning. Reducing deaths in locations where evacuation to high ground is impossible in the short time between ground shaking and arrival of tsunamis requires measures such as vertical evacuation facilities or engineered pathways to safe ground. Yet, very few, if any, such tsunami mitigation projects have been done. In contrast, many tornado safe room and earthquake mitigation projects driven entirely or in largely by life safety have been done with costs in the billions of dollars. The absence of tsunami mitigation measures results from the belief that tsunamis are too infrequent and the costs too high to justify life safety mitigation measures. A simple analysis based on return periods, death rates, and the geographic distribution of high risk areas for these hazards demonstrates that this belief is incorrect: well-engineered tsunami mitigation projects are more cost-effective with higher benefit-cost ratios than almost all tornado or earthquake mitigation projects. Goldfinger's paleoseismic studies of CSZ turbidites indicate return periods for major CSZ tsunamis of about 250-500 years (USGS Prof. Paper 1661-F in press). Tsunami return periods are comparable to those for major earthquakes at a given location in high seismic areas and are much shorter than those for tornados at any location which range from >4,000 to >16,000 years for >EF2 and >EF4 tornadoes, respectively. The average earthquake death rate in the US over the past 100-years is about 1/year, or about 30/year including the 1906 San Francisco earthquake. The average death rate for tornadoes is about 90/year. For CSZ tsunamis, the estimated average death rate ranges from about 20/year (10,000 every 500 years) to 80/year (20,000 every 250 years). Thus, the long term deaths rates from tsunamis, earthquakes and tornadoes are comparable. High hazard areas for tornadoes and earthquakes cover ~40% and ~15% of the contiguous US, ~1,250,000 and ~500,000 square miles, respectively. In marked contrast, tsunami life safety risk is concentrated in communities with significant populations in areas where evacuation to high ground is impossible: probably cost ratio would be about 16 or about 80 for tsunami mitigation projects which cost 5 million or 1 million, respectively. These rough calculations indicate that tsunami mitigation projects in high risk locations are economically justified. More importantly, these results indicate that national and local priorities for natural hazard mitigation should be reconsidered, with tsunami mitigation given a very high priority.
Goettel, K. A.; Rizzo, A.; Sigrist, D.; Bernard, E. N.
Canada has the longest coastline and largest continental margin of any nation in the World. As a result, it is more likely than other nations to experience marine geohazards such as submarine landslides and consequent tsunamis. Coastal landslides represent a specific threat because of their possible proximity to societal infrastructure and high tsunami potential; they occur without warning and with little time lag between failure and tsunami impact. Continental margin landslides are common in the geologic record but rare on human timescales. Some ancient submarine landslides are massive but more recent events indicate that even relatively small slides on continental margins can generate devastating tsunamis. Tsunami impact can occur hundreds of km away from the source event, and with less than 2 hours warning. Identification of high-potential submarine landslide regions, combined with an understanding of landslide and tsunami processes and sophisticated tsunami propagation models, are required to identify areas at high risk of impact.
This qualitative study strives to provide a greater understanding of the past, current, and future state of education in Sri Lanka after the 2004 tsunami. The researchers' key objectives are to provide additional insight to educators of the far-reaching impact of the tsunami via a website they created. Rather than concentrate on the same sort of…
Cashman, Timothy G.; Asing-Cashman, Joyce G.
Following the devastating 11 March 2011 tsunami, two deep-ocean assessment and reporting of tsunamis (DART®)(DART® and the DART® logo are registered trademarks of the National Oceanic and Atmospheric Administration, used with permission) stations were deployed in Japanese waters by the Japanese Meteorological Agency. Two weeks after deployment, on 7 December 2012, a M w 7.3 earthquake off Japan's Pacific coastline generated a tsunami. The tsunami was recorded at the two Japanese DARTs as early as 11 min after the earthquake origin time, which set a record as the fastest tsunami detecting time at a DART station. These data, along with those recorded at other DARTs, were used to derive a tsunami source using the National Oceanic and Atmospheric Administration tsunami forecast system. The results of our analysis show that data provided by the two near-field Japanese DARTs can not only improve the forecast speed but also the forecast accuracy at the Japanese tide gauge stations. This study provides important guidelines for early detection and forecasting of local tsunamis.
Bernard, Eddie; Wei, Yong; Tang, Liujuan; Titov, Vasily
Students are employees of a unit of the United Nations responsible for coordinating disaster relief after a major disaster (the 2004 Asian Earthquake and Tsunami) occurs. The agency needs to understand the situation in each country so that it can coordinate the work of various governments and NGO (nongovernmental organizations) working in the affected area.
Char Bezanson, Eastview High School, Apple Valley, Minnesota
Cuba as neo tectonics structure in the southern of the North American plate had three tsunamis. One of them [local] occurred in the Central-Northern region [1931.10.01, Nortecubana fault], the other was a tele tsunami [1755.11.01, in the SW of the Iberian Peninsula] that hit the Bay of Santiago de Cuba, and the third took place at 1867.11.18, by the regional source of Virgin Islands, which produced waves in the Eastern Cuban region. This tsunami originated to the NE of Puerto Rico in 1918.10.11, with another earthquake of equal magnitude and at similar coordinates, produced a tsunami that did not affect Cuba. Information on the influence of regional tsunami in 1946.08.08 of the NE of the Dominican Republic [Matanzas] in Northwestern Cuba [beaches Guanabo-Baracoa] is contrary to expectations with the waves propagation. The local event of 1939.08.15 attributed to Central- Northern Cuba [Cayo Frances with M = 8.1] does not correspond at all with the maximum magnitude of earthquakes in this region and the potential of the Nortecubana fault. Tsunamis attributed to events such as 1766.06.11 and 1932.02.03 in the Santiago de Cuba Bay are not reflected in the original documents from experts and eyewitnesses. Tsunamis from Jamaica have not affected the coasts of Cuba, despite its proximity. There is no influence in Cuba of tsunamigenic sources of the southern and western parts of the Caribbean, or the Gulf of Mexico. Set out the doubts as to the influence of tsunamis from Hait as to the influence of tsunamis from Haiti and Dominican Republic at Guantanamo Bay which is closer to and on the same latitude, and spatial orientation than the counterpart of Santiago de Cuba, that had impact. The number of fatalities by authors in the Caribbean is different and contradictory. (Author) 76 refs.
We often talk about how different our world is from our parent's world. We then extrapolate this thinking to our children and try to imagine the world they will face. This is hard enough. However, change is changing! The rate at which change is occurring is accelerating. These new ideas, technologies and ecologies appear to be coming at us like tsunamis. Our approach to responding to these oncoming tsunamis will frame the future our children will live in. There are many of these tsunamis; I am just going to focus on three really big ones heading our way.
Antcliff, Richard R.
Long before the devastating December 2004 Indian Ocean event, tsunamis had already been implicated in the widespread death and destruction in Java and Sumatra following the 1883 eruption of Krakatoa. Tsunamis are also blamed for the collapse of the ancient Minoan civilization on Crete. These waves are capable of overrunning almost any coastline in the world and exacting a serious toll on both property and life. This interactive world map lets users explore key tsunamis dating from 3.5 billion years ago, along with a hypothetical future event that might take place in the Atlantic Ocean near the Canary Islands.
BACKGROUND: Headache is one of the most common symptoms in primary care. To improve the quality of headache diagnosis and management with the largest possible benefit for the general population, headache and pain societies around the world have recently been devoting more attention to headache in primary care.The aim of the study was to investigate the potential contribution that national societies can make toward raising the awareness of primary headaches in general practice. FINDINGS: In...
Gantenbein, Andreas R.; Ja?ggi, Christian; Sturzenegger, Mathias; Gobbi, Claudio; Merki-feld, Gabriele S.; Emmenegger, Mark J.; Taub, Ethan; Sa?ndor, Peter S.
Meeting report Julian Hunt, Grant Kopec and Karen Aplin report on new techniques and practical approaches before, during and after devastating events such as tsunamis. © 2010 Royal Astronomical Society.
Hunt, J.; Kopec, G.; Aplin, K.
... Safety Food Safety Water Quality Sanitation & Hygiene Diseases & Health Concerns Information for Clinicians Response & Cleanup After a Tsunami Worker Safety After a Flood Pesticide Safety Guidance Epidemiologic Methods for Relief Operations MMWRs ...
The December, 2004, Indian Ocean tsunami highlighted the need to increase capacity building in the countries most severely affected by the international disaster. In response to this need, the Indian Ocean Tsunami Warning System (IOTWS) Program, under the framework of the UNESCO Intergovernmental Oceanographic Commission (IOC), was developed in order to create "tsunami resilient" communities in the Indian Ocean region. The IOTWS has several components including technical assistance, regional hazard detection, prediction, and warning formulation, national dissemination and communication of warnings, local knowledge and preparedness to act, and regional or sub-regional exchange of lessons learned and best practices. A series of training courses are currently underway in the Indian Ocean region designed to improve the understanding of earthquake seismology and tsunami warnings of staff employed in the day-to-day running of the national tsunami warning systems. Learning is directed through lecturers complemented with computer- based practical sessions. To date five courses have been run, in Indonesia, Thailand, Malaysia, the Maldives and Sri Lanka. Each course was between 5 and 9 days in duration and was sponsored by U.S. Agency for International Development (USAID), the IOC, and the U.S. Geological Survey (USGS). An additional five "follow-on" courses are planned for the region and will be conducted in 2007.
Kong, L.; Mooney, W. D.; Kelly, A.
Los tsunamis, grandes olas extraordinarias típicamente asociadas a terremotos, inundan las zonas costeras provocando erosión y modificaciones morfológicas, pero también transporte y depósito de sedimento en las islas barrera, flechas, estuarios y acantilados. Los efectos y depósitos resultantes dependen de varios factores que se revisan en el texto. Aunque las costas españolas no suelen verse afectadas por grandes tsunamis, existe un largo registro en tiempos históricos...
Dabrio, Cristino J.; Polo Camacho, Mari?a Dolores
Secondary magnetic fields are induced by the flow of electrically conducting seawater through the Earth's primary magnetic field ('ocean dynamo effect'), and hence it has long been speculated that tsunami flows should produce measurable magnetic field perturbations, although the signal-to-noise ratio would be small because of the influence of the solar magnetic fields. Here, we report on the detection of deep-seafloor electromagnetic perturbations of 10-micron-order induced by a tsunami, which propagated through a seafloor electromagnetometer array network. The observed data extracted tsunami characteristics, including the direction and velocity of propagation as well as sea-level change, first to verify the induction theory. Presently, offshore observation systems for the early forecasting of tsunami are based on the sea-level measurement by seafloor pressure gauges. In terms of tsunami forecasting accuracy, the integration of vectored electromagnetic measurements into existing scalar observation systems would represent a substantial improvement in the performance of tsunami early-warning systems. PMID:24399356
Sugioka, Hiroko; Hamano, Yozo; Baba, Kiyoshi; Kasaya, Takafumi; Tada, Noriko; Suetsugu, Daisuke
Full Text Available Background: Vulnerable children undergoing intensive care might still experience pain when they should not, due tonurses and pediatricians insufficient knowledge about how critical illness affects childrens’ signs of pain. How signs ofpain are learned in clinical practice might be one of the remaining aspects in nurses insufficient pain alleviation. In theworkplace learning is directed by what the units shared meaning finds as significant and meaningful to learn. However,what it is viewed as meaningful to learn about pain from the nurses’ perspective might not be meaningful from the child’sperspective. When working together in the PICU, nurses rely on each other and interact in many ways, and theirunderstanding is related to situated knowledge and facilitated by a personal reference group of colleagues. Professionalconcern, depending on culture, traditions, habits, and workplace structures forms the clinical learning patterns in thePICU. However little is known about nurses’ clinical learning patterns or collegial facilitation within the PICU. Theseassumptions lead to the aim of the study: to elucidate patterns in clinical knowledge development and unfold the role offacilitator nurses in relation to pain management in the PICU.Method: The study had a qualitative interpretive design approach using semi-structured interviews, analyzed withqualitative content analysis to elucidate both manifest and latent content.Results: The findings elucidates that the workplace culture supports or hinders learning and collaboration. Knowledgedevelopment within practice is closely connected to the workplace culture and to nurses’ significant networks. Thefindings also clarify that nurses needs to feel safe in the workplace and on an individual level to build and rely onsignificant networks that facilitates their own personal knowledge development. There is an ongoing interaction betweenthe learning patterns and the facilitation the significant networks offer.Conclusions: Nurses need to embrace effective learning about children’s pain from day one. Lack of a facilitatingstructure for learning, lack of assessment within clinical practice, and the focus on the individual nurses’ learning areremaining considerable problems when it comes to alleviating the vulnerable child’s pain. To increase the possibility ofpain alleviation in the clinical setting, it is of importance to attend to the caring culture and build a safe collaborative culture that is patient centered. This requires an environment that allows for open discussion, where questioning andreflecting is a natural part of the culture within the group. These factors need highlighting and thorough examination fromthe organization. Nurses focus on learning, and interact in a learning community of practice that is furthered when theyexperience a safe environment and find that their questions are taken seriously. Approaches to promote a scholarship ofnursing care are needed to develop clinical learning and, consequently, raise the quality of pain care.
Janet Yvonne Mattsson
Full Text Available Se presentan algunos aspectos fundamentales respecto a la matemática y la herramienta computacional que apoyan la compleja descripción del proceso físico tsunami desde dos enfoques específicos. En particular, se aborda analíticamente un modelo hidroelástico simple para el problema de generación de ondas tsunami, el cual permite obtener resultados en el área de ruptura. Por otra parte, el proceso de propagación de las ondas tsunami en el océano y el impacto a lo largo de la línea costera se analiza numéricamente utilizando el enfoque hidrodinámico, presentando en particular una aplicación directa sobre la predicción de tsunamis en México producidos por sismos potenciales en la trinchera Mesoamericana mediante el diseño de un “Módulo Sintetizador de Tsunamis” para simular tsunamis originados por sismos ocurridos en la zona de subducción de la costa occidental de México.We present some key aspects regarding the mathematics and the computational tool that support the complex description of the physical process tsunami from two specific approaches. In particular, it addresses analytically a simple hydroelastic model for the problem of tsunami wave generation, which provides results in the rupture area. Moreover, the propagation of tsunami waves in the ocean and the impact along the coastline is analyzed numerically using the hydrodynamic approach, presenting in particular a direct application to the prediction of tsunamis in Mexico caused by potential earthquakes in the Mesoamerican trench through the design of a “Tsunami Toolbox” to simulate tsunamis caused by earthquakes in the subduction zone on the western coast of Mexico.
Rodrigo González González
The Northern California counties of Del Norte, Humboldt, and Mendocino account for over 30% of California's coastline and is one of the most seismically active areas of the contiguous 48 states. The region is at risk from earthquakes located on- and offshore and from tsunamis generated locally from faults associated with the Cascadia subduction zone (CSZ) and from distant sources elsewhere in the Pacific. In 1995 the California Geological Survey (CGS) published a scenario for a CSZ earthquake that included both strong ground shaking effects and a tsunami. As a result of the scenario, the Redwood Coast Tsunami Work Group (RCTWG), an organization of government agencies, tribes, service groups, academia and the private sector, was formed to coordinate and promote earthquake and tsunami hazard awareness and mitigation in the three-county region. The RCTWG and its member agencies projects include education/outreach products and programs, tsunami hazard mapping, signage and siren planning. Since 2008, RCTWG has worked with the California Emergency Management Agency (Cal EMA) in conducting tsunami warning communications tests on the North Coast. In 2007, RCTWG members helped develop and carry out the first tsunami training exercise at FEMA's Emergency Management Institute in Emmitsburg, MD. The RCTWG has facilitated numerous multi-agency, multi-discipline coordinated exercises, and RCTWG county tsunami response plans have been a model for other regions of the state and country. Eight North Coast communities have been recognized as TsunamiReady by the National Weather Service, including the first National Park the first State Park and only tribe in California to be so recognized. Over 500 tsunami hazard zone signs have been posted in the RCTWG region since 2008. Eight assessment surveys from 1993 to 2010 have tracked preparedness actions and personal awareness of earthquake and tsunami hazards in the county and additional surveys have tracked public awareness and tourist concerns about tsunami hazard signs. Over the seventeen-year period covered by the surveys, the percent with houses secured to foundations has increased from 58 to 84 percent, respondents aware of a local tsunami hazard increased from 51 to 89 percent and knowing what the Cascadia subduction zone is from 16 to 57 percent. In 2009, the RCTWG was recognized by the Western States Seismic Policy Council (WSSPC) with an award for innovation and in 2010, the RCTWG-sponsored class "Living on Shaky Ground" was awarded WSSPC's overall Award in Excellence. The RCTWG works closely with CGS and Cal EMA on a number of projects including tsunami mapping, evacuation zone planning, siren policy, tsunami safety for boaters, and public education messaging. Current projects include working with CGS to develop a "playbook" tsunami mapping product to illustrate the expected effects from a range of tsunami source events and assist local governments in focusing future response actions to reflect the range expected impacts from distant source events. Preparedness efforts paid off on March 11, 2011 when a tsunami warning was issued for the region and significant damage occurred in harbor regions of Del Norte County and Mendocino County. Full-scale evacuations were carried out in a coordinated manner and the majority of the commercial fishing fleet in Crescent City was able to exit the harbor before the tsunami arrived.
Dengler, L.; Henderson, C.; Larkin, D.; Nicolini, T.; Ozaki, V.
The dissertation's purpose was to document and discuss what 10 elementary science teachers, deemed exemplary by administrators, do in the science classroom to reflect the National Science Education Teaching Standards. To make implications for teacher education this report also explored these teachers' science professional development backgrounds. A qualitative triangulated approach of surveys, interviews and observations was used to document actualities, of what theorists have proposed should take place in a standards-based elementary science classroom. Several behavior patterns were identified among these exemplary teachers and their students. These teachers organized for collaborative and individual responsibility; planned according to the needs and interests of their students; encouraged scientific discourse and decision making among their students; facilitated the scientific inquiry process with hands-on, higher-order activities; and used alternative assessment strategies. They were involved in collaboration with peers in planning, training, and decision malting at the school, district, state, and national levels. Exposure to professional development and experience were identified as having the greatest influence on these exemplary teachers. During science lessons taught by these teachers, students were observed in high degrees of cooperation and collaboration with peers while engaging in higher-order discourse and process inquiry, regardless of their academic or social levels. Implications for science teachers' professional development are made, as are suggestions for future research in this area.
Pittman, Margaret Evans
I have expanded substantially my list of information sources on: tsunami generation (sources, impulsive mechanisms), propagation, effects of nearshore bathymetry, and wave run-up on shore - including physical (hydraulic) modeling and numerical modeling. This expanded list includes the subjects of field investigations of tsunamis soon after an event; damage effects in harbors on boats, ships, and facilities; tsunami wave-induced forces; damage by tsunami waves to structures on shore; scour/ero...
Wiegel, Robert L.
Tsunamis are gravity waves that propagate near the ocean surface. They belong to the same family as common sea waves that we enjoy at the beach; however, tsunamis are distinct in their mode of generation and in their characteristic period, wavelength, and velocity. The type of tsunamis that induce widespread damage number about one or two per decade. Thus 'killer tsunamis' although fearful, are a relatively rare phenomenon
In recent years the study of tsunamis has shifted away from theoretical modeling of tsunami source, wave propagation and run-up toward multidisciplinary investigations, with a clear emphasis on field studies. These studies produce a much more comprehensive understand of the various earth surface processes that generate tsunamis and the ways that tsunamis modify coastlines often destroying property and producing fatalities. This collection of papers highlights the varied approaches now being u...
Alastair G Dawson, Ed; Christopherf Waythomas, Ed; Barbara H Keating, Ed; Birkhauser Verlag A
Full Text Available A catastrophic tsunami on December 26, 2004 caused devastation in the coastal region of six southern provinces of Thailand on the Andaman Sea coast. This paper summaries the characteristics of tsunami with the aim of informing and warning the public and reducing future casualties and damage.The first part is a review of the records of past catastrophic tsunamis, namely those in Chile in 1960, Alaska in 1964, and Flores, Java, Indonesia, in 1992, and the lessons drawn from these tsunamis. An analysis and the impact of the 2004 Sumatra tsunami is then presented and remedial measures recommended.Results of this study are as follows:Firstly, the 2004 Sumatra tsunami ranked fourth in terms of earthquake magnitude (9.0 M after those in 1960 in Chile (9.5 M, 1899 in Alaska (9.2 M and 1964 in Alaska (9.1 M and ranked first in terms of damage and casualties. It was most destructive when breaking in shallow water nearshore.Secondly, the best alleviation measures are 1 to set up a reliable system for providing warning at the time of an earthquake in order to save lives and reduce damage and 2 to establish a hazard map and implement land-use zoning in the devastated areas, according to the following principles:- Large hotels located at an elevation of not less than 10 m above mean sea level (MSL- Medium hotels located at an elevation of not less than 6 m above MSL- Small hotel located at elevation below 6 m MSL, but with the first floor elevated on poles to allow passage of a tsunami wave- Set-back distances from shoreline established for various developments- Provision of shelters and evacuation directionsFinally, public education is an essential part of preparedness.
Many past studies have verified numerical simulations of tsunamis using only qualitative and subjective methods. This paper investigates the relative merits of several indices that can be used to objectively verify tsunami model performance. A number of commonly used indices, such as error in the maximum amplitude and root-mean-square error, are considered, as well as some further indices that have been developed for other specific applications. Desirable qualities of the indices are presented and these include computational efficiency, invariance when applied to tsunamis of any size or to time series of varying length (including relatively short series), and the ability to clearly identify a single best prediction from within a set of simulations. A scenario from the T2 tsunami scenario database is chosen as the control. From this, time series of sea-level elevations are extracted at designated test points located at a range of distances from the tsunami source region. Parameters of the T2 database are perturbed in order to examine the performance of the indices. Of the indices examined, several performed better than others, with Wilmott's Index of Agreement and Watterson's transformed Mielke index found to be the best. Combining data from multiple locations was shown to improve the performance of the indices. This study forms the basis for future evaluation of the indices using real observations of tsunamis.
Allen, Stewart C. R.; Greenslade, Diana J. M.
The March 11th 2011 Tohoku-iki earthquake was the fifth largest on Earth in the last 50 years, it created one of the most devastating tsunamis in history. Dave Tappin describes the background to the tsunami and its impact based on his research on tsunamis and visits to Japan over the past three months.
An incomplete catalogue of tsunamis in the written record hinders tsunami risk assessment. Tsunami deposits, hard evidence of tsunami, can be used to extend the written record. The two primary factors in tsunami risk, tsunami frequency and magnitude, can be addressed through field and modeling studies of tsunami deposits. Recent research has increased the utility of tsunami deposits in tsunami risk assessment by improving the ability to identify tsunami deposits and developing models to determine tsunami magnitude from deposit characteristics. Copyright ASCE 2008.
Mitigation of tsunami risk requires a combination of emergency preparedness for evacuation in addition to providing structural resilience of critical facilities, infrastructure, and key resources necessary for immediate response and economic and social recovery. Critical facilities would include emergency response, medical, tsunami refuges and shelters, ports and harbors, lifelines, transportation, telecommunications, power, financial institutions, and major industrial/commercial facilities. The Tsunami Loads and Effects Subcommittee of the ASCE/SEI 7 Standards Committee is developing a proposed new Chapter 6 - Tsunami Loads and Effects for the 2016 edition of the ASCE 7 Standard. ASCE 7 provides the minimum design loads and requirements for structures subject to building codes such as the International Building Code utilized in the USA. In this paper we will provide a review emphasizing the intent of these new code provisions and explain the design methodology. The ASCE 7 provisions for Tsunami Loads and Effects enables a set of analysis and design methodologies that are consistent with performance-based engineering based on probabilistic criteria. . The ASCE 7 Tsunami Loads and Effects chapter will be initially applicable only to the states of Alaska, Washington, Oregon, California, and Hawaii. Ground shaking effects and subsidence from a preceding local offshore Maximum Considered Earthquake will also be considered prior to tsunami arrival for Alaska and states in the Pacific Northwest regions governed by nearby offshore subduction earthquakes. For national tsunami design provisions to achieve a consistent reliability standard of structural performance for community resilience, a new generation of tsunami inundation hazard maps for design is required. The lesson of recent tsunami is that historical records alone do not provide a sufficient measure of the potential heights of future tsunamis. Engineering design must consider the occurrence of events greater than scenarios in the historical record, and should properly be based on the underlying seismicity of subduction zones. Therefore, Probabilistic Tsunami Hazard Analysis (PTHA) consistent with source seismicity must be performed in addition to consideration of historical event scenarios. A method of Probabilistic Tsunami Hazard Analysis has been established that is generally consistent with Probabilistic Seismic Hazard Analysis in the treatment of uncertainty. These new tsunami design zone maps will define the coastal zones where structures of greater importance would be designed for tsunami resistance and community resilience. Structural member acceptability criteria will be based on performance objectives for a 2,500-year Maximum Considered Tsunami. The approach developed by the ASCE Tsunami Loads and Effects Subcommittee of the ASCE 7 Standard would result in the first national unification of tsunami hazard criteria for design codes reflecting the modern approach of Performance-Based Engineering.
Full Text Available The Papua New Guinea (PNG tsunami of July 1998 was a seminal event because it demonstrated that relatively small and relatively deepwater Submarine Mass Failures (SMFs can cause devastating local tsunamis that strike without warning. There is a comprehensive data set that proves this event was caused by a submarine slump. Yet, the source of the tsunami has remained controversial. This controversy is attributed to several causes. Before the PNG event, it was questionable as to whether SMFs could cause devastating tsunamis. As a result, only limited modelling of SMFs as tsunami sources had been undertaken, and these excluded slumps. The results of these models were that SMFs in general were not considered to be a potential source of catastrophic tsunamis. To effectively model a SMF requires fairly detailed geological data, and these too had been lacking. In addition, qualitative data, such as evidence from survivors, tended to be disregarded in assessing alternative tsunami sources. The use of marine geological data to identify areas of recent submarine failure was not widely applied.
The disastrous loss of life caused by the PNG tsunami resulted in a major investigation into the area offshore of the devastated coastline, with five marine expeditions taking place. This was the first time that a focussed, large-scale, international programme of marine surveying had taken place so soon after a major tsunami. It was also the first time that such a comprehensive data set became the basis for tsunami simulations. The use of marine mapping subsequently led to a larger involvement of marine geologists in the study of tsunamis, expanding the knowledge base of those studying the threat from SMF hazards. This paper provides an overview of the PNG tsunami and its impact on tsunami science. It presents revised interpretations of the slump architecture based on new seabed relief images and, using these, the most comprehensive tsunami simulation of the PNG event to date. Simulation results explain the measured runups to a high degree. The PNG tsunami has made a major impact on tsunami science. It is one of the most studied SMF tsunamis, yet it remains the only one known of its type: a slump.
D. R. Tappin
The interesting papers by Margaritondo (2005 Eur. J. Phys. 26 401) and by Helene and Yamashita (2006 Eur. J. Phys. 27 855) analysed the great Indian Ocean tsunami of 2004 using a simple one-dimensional canal wave model, which was appropriate for undergraduate students in physics and related fields of discipline. In this paper, two additional, easily understandable models, suitable for the same level of readership, are proposed: one, a two-dimensional model in flat space, and two, the same on a spherical surface. The models are used to study the tsunami produced by the central Kuril earthquake of November 2006. It is shown that the two alternative models, especially the latter one, give better representations of the wave amplitude, especially at far-flung locations. The latter model further demonstrates the enhancing effect on the amplitude due to the curvature of the Earth for far-reaching tsunami propagation
In the vast literature on tsunami research, few articles have been devoted to energy issues. A theoretical investigation on the energy of waves generated by bottom motion is performed here. We start with the full incompressible Euler equations in the presence of a free surface and derive both dispersive and non-dispersive shallow-water equations with an energy equation. It is shown that dispersive effects only appear at higher order in the energy budget. Then we solve the Cauchy-Poisson problem of tsunami generation for the linearized water wave equations. Exchanges between potential and kinetic energies are clearly revealed.
Although tides and tsunamis are both shallow water waves, it does not follow that they are equally amenable to an observational program using an orbiting altimeter on a satellite. A numerical feasibility investigation using a hypothetical satellite orbit, real tide observations, and sequentially increased levels of white noise has been conducted to study the degradation of the tidal harmonic constants caused by adding noise to the tide data. Tsunami waves, possibly a foot high and one hundred miles long, must be measured in individual orbits, thus requiring high relative resolution.
Zetler, B. D.
In this activity, by the Lane Community College MAPS GIS Program, students work in teams to evaluate Oregon citiesÃ¢ÂÂ tsunami evacuation plans related to a potential 8.1 coastal earthquake. Teams use additional information from a Web-based GIS to study the multi-faceted nature of earthquake damage in addition to tsunami impacts and make recommendations to improve the existing plan. The data are from the Oregon Geospatial Data Clearinghouse and the Oregon Department of Geology and Mines. On this site, visitors will find both the teacher version of the lesson plan and the student exercise, both as PDFs.
Post-tsunami scientific field surveys are critical for improving the understanding of tsunamis and developing tools and programs to mitigate their effects. After a destructive tsunami, international, national, and local tsunami scientists need to gather information, much of which is perishable or degrades significantly with time. An influx of researchers can put stress on countries already overwhelmed by humanitarian response to the disaster and by the demands of emergency management and other support agencies. In the United States, in addition to university research scientists, government agencies such as the National Oceanic and Atmospheric Administration (NOAA), the U.S. Geologic Survey (USGS), and state/territorial emergency management agencies and geological surveys endeavor to collect physical and social science data to better understand the physics of tsunamis and the impact they have on coastal communities and ecosystems. After a Presidential Major Disaster Declaration, the Federal Emergency Management Agency (FEMA) Joint Field Office works with state/territory emergency management agencies to coordinate response to disasters. In the short-term, the collection and immediate sharing of data enable decision-making that better organizes and deploys often-limited resources to the areas most critically in need of response; and in the long-term, improves recovery planning that will mitigate the losses from the next tsunami. Recent tsunamis have emphasized the need for improved coordination of data collection among scientists and federal, state, and local emergency managers. Improved coordination will ensure data collection efforts are carried out in a safe, secure, efficient, and timely manner. To improve coordination of activities that will better integrate the scientific investigations with government response, the US National Tsunami Hazard Mitigation Program and Pacific Risk Management 'Ohana (PRiMO) are working together to develop a consistent framework for a tsunami technical clearinghouse (TTC). The goals of the TTC, which would include at a minimum an electronic information server but could also include a physical location, are to: 1) assist in the response to, damage assessment of, and early recovery from the natural disaster; 2) facilitate researcher access to the affected areas; and 3) contribute to the capture of valuable and perishable data. The Working Group, composed of representatives from NOAA, USGS, FEMA, and state and local emergency managers and geoscientists, will engage with other stakeholders and the science community to review existing national standard operating procedures for post-tsunami scientific field surveys and data collection, as well as make recommendations for domestic application. The outcomes are intended to propose a national structure that can be consistently implemented within each state and territory.
Kong, L. S.; Chiesa, C.; Dunbar, P. K.; Huart, J.; Richards, K.; Shulters, M.; Stein, A.; Tamura, G.; Wilson, R. I.; Young, E.
Full Text Available On 26thDecember 2004, a strong Indian Ocean earthquake of moment magnitude 9 generated a deadly tsunami that hit the west coast of southern Thailand and many coastal nations of the Indian Ocean. Two tsunami-affected areas on the Thai Andaman coast (Ao Kheuy beach and Khuk Khak beach were investigated. Multiple sediment layers in the tsunami deposits are identified and are analyzed. The sediment transportation patterns are also determined. Tsunami deposits consist of graded sand layers overlying the pre-existing soil. The particle size profile of the tsunami sediment and the plot of grain-size standard deviation with depth are used to identify major layers in tsunami deposit. There are three major sediment layers in the tsunami deposit in the study areas. They reflect three depositional sequences created by three tsunami run-ups. The mean grain-size of tsunami deposit and the results of sediment trend analysis show that the tsunami deposit is generally fining upwards and landwards. Each major sediment layer is created by sediments settled from suspension in a set of run-up and backwash. The percentage by weight of sediment settled from suspension during the backwash is small when it is compared to the percentage by weight of sediment settled from suspension during the run-up. The 1stdepositional sequence has higher quantity of coarse grain particles than the following depositional sequences. At a mild slope shore face, sediments are transported and deposited on land far from their origins. The number of major sediment layers in tsunami deposit can be used as the extending data for reconstructing individual tsunami run-up by using numerical and/or simple models.
Full Text Available CENALT (CENtre d’ALerte aux Tsunamis is responsible for the French National Tsunami Warning Centre (NTWC. The CENALT is established in the framework of the Unesco/IOC/ICG/NEAMTWS. Its objective is to transmit a warning message in less than fifteen minutes for any events that could trigger a tsunami in the Western Mediterranean Sea and the North- Eastern Atlantic Ocean. The data collected from French installations and from institutions of European and North African countries is processed with software that permits early epicenter location of seismic events and measurements of expected tsunami impacts on the shore. On-duty analysts revise interactively all the generated information and use references of historical tsunami and earthquake databases - as well as computed tsunami scenarios – in order to disseminate the more comprehensive message possible.
The tsunami generated on December 26, 2004 due to Sumatra earthquake of magnitude 9.3 resulted in inundation at the various coastal sites of India. The site selection and design of Indian nuclear power plants demand the evaluation of run up and the structural barriers for the coastal plants: Besides it is also desirable to evaluate the early warning system for tsunamigenic earthquakes. The tsunamis originate from submarine faults, underwater volcanic activities, sub-aerial landslides impinging on the sea and submarine landslides. In case of a submarine earthquake-induced tsunami the wave is generated in the fluid domain due to displacement of the seabed. There are three phases of tsunami: generation, propagation, and run-up. Reactor Safety Division (RSD) of Bhabha Atomic Research Centre (BARC), Trombay has initiated computational simulation for all the three phases of tsunami source generation, its propagation and finally run up evaluation for the protection of public life, property and various industrial infrastructures located on the coastal regions of India. These studies could be effectively utilized for design and implementation of early warning system for coastal region of the country apart from catering to the needs of Indian nuclear installations. This paper presents some results of tsunami waves based on finite difference numerical approaches with shallow water wave theory. The present paper evaluate the results of various simulation i.e. Single fault Sumatrarious simulation i.e. Single fault Sumatra model, four and five fault Sumatra Model, Nias insignificant tsunami and also some parametric studies results for tsunami waring system scenario generation. A study is carried for the tsunami due to Sumatra earthquake in 2004 with TUNAMI-N2 software. Bathymetry data available from the National Geophysical Data Center was used for this study. The single fault and detailed four and five fault data were used to calculate sea surface deformations which were subsequently used as initial conditions for Sumatra 2004 tsunami propagation simulation. The paper also presents a hypothetical study by assuming the earthquake rupture on northern fault only as compared to complete (northern and southern) rupture segment and the resulting tsunami propagation scenario. All of the studies provide the results in terms of wave heights and compare them with the reported simulation, satellite observation and field observed reported data. The paper includes the parametric studies on the possible fault line for Sumatra fault line for support for early tsunami warning. The various other events i.e Java, Nias, Makaran, Andaman etc are also discussed in the paper. (author)
Trans-oceanic wave propagation is one of the most time/CPU consuming parts of the tsunami modeling process. The so-called Method Of Splitting Tsunami (MOST) software package, developed at PMEL NOAA USA (Pacific Marine Environmental Laboratory of the National Oceanic and Atmospheric Administration, USA), is widely used to evaluate the tsunami parameters. However, it takes time to simulate trans-ocean wave propagation, that is up to 5 hours CPU time to "drive" the wave from Chili (epicenter) to the coast of Japan (even using a rather coarse computational mesh). Accurate wave height prediction requires fine meshes which leads to dramatic increase in time for simulation. Computation time is among the critical parameter as it takes only about 20 minutes for tsunami wave to approach the coast of Japan after earthquake at Japan trench or Sagami trench (as it was after the Great East Japan Earthquake on March 11, 2011). MOST solves numerically the hyperbolic system for three unknown functions, namely velocity vector and wave height (shallow water approximation). The system could be split into two independent systems by orthogonal directions (splitting method). Each system can be treated independently. This calculation scheme is well suited for SIMD architecture and GPUs as well. We performed adaptation of MOST package to GPU. Several numerical tests showed 40x performance gain for NVIDIA Tesla C2050 GPU vs. single core of Intel i7 processor. Results of numerical experiments were compared with other available simulation data. Calculation results, obtained at GPU, differ from the reference ones by 10^-3 cm of the wave height simulating 24 hours wave propagation. This allows us to speak about possibility to develop real-time system for evaluating tsunami danger.
Lavrentyev, Mikhail; Romanenko, Alexey
From the National Tsunami Hazard Mitigation Program, the Deep-ocean Assessment and Reporting of Tsunamis (DART) page contains real time sea level data which can be modified by site and transmitter, type of data set, database, and time range. Data may be viewed through a browser or downloaded (.dbf, .gz).
The CENALT (CENtre d'Alerte aux Tsunamis) is responsible for the French NTWC (National Tsunami Warning Center). This center was established through a project that was requested by the French Ministry of Interior and the Ministry of Sustainable Development. It is implemented by the Commissariat à l'énergie atomique et aux énergies alternatives (CEA), the French Hydrographic and Oceanographic Service (SHOM) and the Centre National de la Recherche Scientifique (CNRS), and is based in Bruyères-le-Châtel (30 km from Paris). This center is based on three main components: seismic network data, sea level network data, dissemination system and processing and analyzing softwares and is operating on a 24/7 basis. The CENALT has established scientific cooperation with 8 institutions and implemented and funded private leased lines to exchange data with institutions from 5 different European countries (Germany, Italy, Portugal, Spain, Tunisia). The seismic data are processed with the Seiscomp 3 software. SHOM is working on making all French tide-gauge stations operated and available in real-time in 2012, and they installed 5 new tide gage stations. The tide gage data will be processed with a customized version of the Guitar (Gempa) software allowing the detection of tsunami signals, complemented by other softwares developed by the CEA. Historical tsunami databases (sources and observations) and earthquake databases, mostly based on available international databases, have been synthetized by CEA to produce information maps in real time, used to guide operators of permanence. Precomputed tsunami scenarios are implemented to build in real time maps of the highest tsunami impact expected in deep water. Along with an optimized tsunami modeling tool, these softwares help to define the areas where the tsunami may be observed and cause damage. The CENALT has been operating since early January 2012 as a pre-operational service and will be fully operational in July 2012. It is also ready to act as Candidate Watch Provider covering Western Mediterranean by July 2012.
Schindelé, F.; Bossu, R.; Alabrune, N.; Arnoul, P.; Duperray, P.; Gailler, A.; Guilbert, J.; Hébert, H.; Hernandez, B.; Loevenbruck, A.; Roudil, P.
... small boats, so physically moving yourself to higher ground may be the only option. - Damaging wave activity and unpredictable currents can affect harbors for hours following the initial tsunami impact on the coast. Contact the harbor authority before returning to port making ...
Over 75 tsunamis have been documented in the Caribbean and Adjacent Regions over the past 500 years. While most have been generated by local earthquakes, distant generated tsunamis can also affect the region. For example, waves from the 1755 Lisbon earthquake and tsunami were observed in Cuba, Dominican Republic, British Virgin Islands, as well as Antigua, Martinique, Guadalupe and Barbados in the Lesser Antilles. Since 1500, at least 4484 people are reported to have perished in these killer waves. Although the tsunami generated by the 2010 Haiti earthquake claimed only a few lives, in the 1530 El Pilar, Venezuela; 1602 Port Royale, Jamaica; 1918 Puerto Rico; and 1946 Samaná, Dominican Republic tsunamis the death tolls ranged to over a thousand. Since then, there has been an explosive increase in residents, visitors, infrastructure, and economic activity along the coastlines, increasing the potential for human and economic loss. It has been estimated that on any day, upwards of more than 500,000 people could be in harm's way just along the beaches, with hundreds of thousands more working and living in the tsunamis hazard zones. Given the relative infrequency of tsunamis, exercises are a valuable tool to test communications, evaluate preparedness and raise awareness. Exercises in the Caribbean are conducted under the framework of the UNESCO IOC Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) and the US National Tsunami Hazard Mitigation Program. On March 23, 2011, 34 countries and territories participated in the first CARIBE WAVE/LANTEX regional tsunami exercise, while in the second exercise on March 20, 2013 a total of 45 countries and territories participated. 481 organizations (almost 200 more than in 2011) also registered to receive the bulletins issued by the Pacific Tsunami Warning Center (PTWC), West Coast and Alaska Tsunami Warning Center and/or the Puerto Rico Seismic Network. The CARIBE WAVE/LANTEX 13 scenario simulated a tsunami generated by a magnitude 8.5 earthquake originating north of Oranjestad, Aruba in the Caribbean Sea. For the first time earthquake impact was included in addition to expected tsunami impact. The initial message was issued by the warning centers over the established channels, while different mechanisms were then used by participants for further dissemination. The enhanced PTWC tsunami products for the Caribbean were also made available to the participants. To provide feedback on the exercise an online survey tool with 85 questions was used. The survey demonstrated satisfaction with exercise, timely receipt of bulletins and interest in the enhanced PTWC products. It also revealed that while 93% of the countries had an activation and response process, only 59% indicated that they also had an emergency response plan for tsunamis and even fewer had tsunami evacuation plans and inundation maps. Given that 80% of those surveyed indicated that CARIBE WAVE should be conducted annually, CARIBE EWS decided that the next exercise be held on March 26, 2014, instead of waiting until 2015.
von Hillebrandt-Andrade, C.; Whitmore, P.; Aliaga, B.; Huerfano Moreno, V.
Full Text Available SciELO Costa Rica | Language: Spanish Abstract in spanish Se presentan algunos aspectos fundamentales respecto a la matemática y la herramienta computacional que apoyan la compleja descripción del proceso físico tsunami desde dos enfoques específicos. En particular, se aborda analíticamente un modelo hidroelástico simple para el problema de generación de o [...] ndas tsunami, el cual permite obtener resultados en el área de ruptura. Por otra parte, el proceso de propagación de las ondas tsunami en el océano y el impacto a lo largo de la línea costera se analiza numéricamente utilizando el enfoque hidrodinámico, presentando en particular una aplicación directa sobre la predicción de tsunamis en México producidos por sismos potenciales en la trinchera Mesoamericana mediante el diseño de un “Módulo Sintetizador de Tsunamis” para simular tsunamis originados por sismos ocurridos en la zona de subducción de la costa occidental de México. Abstract in english We present some key aspects regarding the mathematics and the computational tool that support the complex description of the physical process tsunami from two specific approaches. In particular, it addresses analytically a simple hydroelastic model for the problem of tsunami wave generation, which p [...] rovides results in the rupture area. Moreover, the propagation of tsunami waves in the ocean and the impact along the coastline is analyzed numerically using the hydrodynamic approach, presenting in particular a direct application to the prediction of tsunamis in Mexico caused by potential earthquakes in the Mesoamerican trench through the design of a “Tsunami Toolbox” to simulate tsunamis caused by earthquakes in the subduction zone on the western coast of Mexico.
Rodrigo, González González; Modesto, Ortiz Figueroa; José Miguel, Montoya Rodríguez.
On the Pacific Northwest an oceanic tectonic plate (Juan de Fuca) is being pulled and driven (subducted) beneath the North American continental plate. Earthquakes generated along that fault may produce local tsunamis. Local tsunamis are those generated by earthquakes near the coast. This site provides links to external webpages describing the physics behind a tsunami. Resources featured in the links include glossary of terms and photo galleries.
The instrumentation for the tide stations has been improved with the replacement of the old Ballauf Standard tide gauge by the bubbler type in 15 locations besides the installation of five Handar Data Collection Platforms (DCP) provided by U.S.NOAA. The existing seismic network is still far from having a good coverage of the country; however, four short period seismometers have been installed lately around the Iquique seismic gap (Latitude 20 deg. S), linked to the Geophysics Institute Office in Santiago, and the two THRUST seismic triggers are in operation at Iquique and Valparaiso ports. Communications with the National Emergency Office has been improved with a HF transmitter which permits linking with all the Regional Emergency Offices along the country. The Standard Operations Plan in Case of Tsunami has been tested in a tsunami simulation exercise, where some problems arised between different emergency agencies; a revision of the Plan has been adopted. (author). 6 figs
Full Text Available This is Part 3 of Tsunami Information Sources published by Robert L. Wiegel, as Technical Report UCB/HEL 2006-3 of the Hydraulic Engineering Laboratory of the Department of Civil & Environmental Engineering of the University of California at Berkeley. Part 3 is published in "SCIENCE OF TSUNAMI HAZARDS" -with the author's permission -so that it can receive wider distribution and use by the Tsunami Scientific Community.
Robert L. Wiegel
This is Part 3 of Tsunami Information Sources published by Robert L. Wiegel, as Technical Report UCB/HEL 2006-3 of the Hydraulic Engineering Laboratory of the Department of Civil & Environmental Engineering of the University of California at Berkeley. Part 3 is published in "SCIENCE OF TSUNAMI HAZARDS" -with the author's permission -so that it can receive wider distribution and use by the Tsunami Scientific Community.
Wiegel, Robert L.
Full Text Available Tsunami Information Sources, Part 4, was originally published, on 14 March 2008, as a Hydraulic Engineering Laboratory, Report UCB/HEL 2008-1, of the Dept. of Civil and Environmental Engineering of the University of California at Berkeley. It is published now in "SCIENCE OF TSUNAMI HAZARDS" with the permission of the author, so that it can receive wider distribution and use by the Tsunami Scientific Community.
Robert L. Wiegel
The New Zealand Ministry of Science and Innovation (MSI) has sponsored a 3-year collaborative project involving industry, government and university research groups to better assess and prepare for tsunami hazards in New Zealand ports and harbors. As an island nation, New Zealand is highly dependent on its maritime infrastructure for commercial and recreational interests. The recent tsunamis of 2009, 2010 and 2011 (Samoa, Chile and Japan) highlighted the vulnerability of New Zealand's marine infrastructure to strong currents generated by such far field events. These events also illustrated the extended duration of the effects from such tsunamis, with some of the strongest currents and highest water levels occurring many hours, if not days after the tsunami first arrival. In addition, New Zealand also sits astride the Tonga-Kermadec subduction zone, which given the events of recent years, cannot be underestimated as a major near field hazard. This presentation will discuss the modeling and research strategy that will be used to mitigate tsunami hazards in New Zealand ports and harbors. This will include a detailed time-series analysis (including Fourier and discrete Wavelet techniques) of water levels recorded throughout New Zealand form recent tsunami events (2009 Samoa, 2010 Chile and 2011 Japan). The information learned from these studies will guide detailed numerical modeling of tsunami induced currents at key New Zealand ports. The model results will then be used to guide a structural analysis of the relevant port structures in terms of hydrodynamic loads as well as mooring and impact loads due to vessel and/or debris. Ultimately the project will lead to an improvement in New Zealand's tsunami response plans by providing a decision making flow chart, targeted for marine facilities, to be used by emergency management officials during future tsunami events.Tsunami effects at Port Charles, New Zealand: (top) inundation into a neighborhood and (bottom left and right) tsunami induced currents and surface agitation. The small jetty indicated with the arrow is overtopped in the second image (indicated by the oval)
Borrero, J. C.; Wotherspoon, L.; Power, W. L.; Goring, D.; Barberopoulou, A.; Melville, B.; Shamseldin, A.
Full Text Available This is a study of tsunami wave propagation along the waveguide on a bottom ridge with flat sloping sides, using the wave rays method. During propagation along such waveguide the single tsunami wave transforms into a wave train. The expression for the guiding velocities of the fastest and slowest signals is defined. The tsunami wave behavior above the ocean bottom ridges, which have various model profiles, is investigated numerically with the help of finite difference method. Results of numerical experiments show that the highest waves are detected above a ridge with flat sloping sides. Examples of tsunami propagation along bottom ridges of the Pacific Ocean are presented.
Andrei G. Marchuk
Cette thèse est consacrée à la modélisation des tsunamis. La vie de ces vagues peut être conditionnellement divisée en trois parties: génération, propagation et inondation. Dans un premier temps, nous nous intéressons à la génération de ces vagues extrêmes. Dans cette partie du mémoire, nous examinons les différentes approches existantes pour la modélisation, puis nous en proposons d'autres. La conclusion principale à laquelle nous sommes arrivés est que le couplage entre la...
A writer from the SmallBizPipeline recently wrote an article reviewing some of the ways technology has been used to facilitate aid distribution and locate those missing after the Tsunami that hit several countries in Asia on December 26, 2004. This article (1) reports from a socialist perspective on the reasons why there was no early warning for the people who suffered from the recent tsunami, many of which are not related to a lack of technology. Nonetheless, predicting the next big earthquake is still beyond the control of scientists, according to this article from the Why Files (4). This website from the USGS (5) provides an overview of the magnitude of the most recent earthquake and links to other pages that help put the catastrophe in perspective in terms of previous earthquakes. This next website (6) proposes a lesson plan for calculating the magnitude of an earthquake, with links to some related information. Finally, this article (7) from the Christian Science Monitor highlights a low-tech way to minimize the effect of Tsunamis --mangroves.
Full Text Available Indian Ocean (2004 Tsunami and following tragic consequences demonstrated lack of relevant experience and preparedness among involved coastal nations. After the event, scientific and forecasting circles of affected countries have started a capacity building to tackle similar problems in the future. Different approaches have been used for tsunami propagation, such as Boussinesq and Nonlinear Shallow Water Equations (NSWE. These approximations were obtained assuming different relevant importance of nonlinear, dispersion and spatial gradient variation phenomena and terms. The paper describes further development of original TUNAMI-N2 model to take into account additional phenomena: astronomic tide, sea bottom friction, dispersion, Coriolis force, and spherical curvature. The code is modified to be suitable for operational forecasting, and the resulting version (TUNAMI-N2-NUS is verified using test cases, results of other models, and real case scenarios. Using the 2004 Tsunami event as one of the scenarios, the paper examines sensitivity of numerical solutions to variation of different phenomena and parameters, and the results are analyzed and ranked accordingly.
The Tsunami Warning System of the Pacific exists as an example of participatory coordination between ICG/ITSU member nations throughout the Pacific Basin. The involvement and participation by many nations has continued to result in significant improvements in the TWS. Although recent operational improvements at PTWC have resulted in the provision of enhanced tsunami warning services, even greater improvements are anticipated over the coming year as PTWC implements the improved automation technology provided by the Concurrent/Masscomp 6600 minicomputer, increased coverage for both seismic and sea level data, improved tsunami evaluation techniques, and increased participation by ICG/ITSU participants. 2 figs
Full Text Available I have expanded substantially my list of information sources on: tsunami generation (sources, impulsive mechanisms, propagation, effects of nearshore bathymetry, and wave run-up on shore - including physical (hydraulic modeling and numerical modeling. This expanded list includes the subjects of field investigations of tsunamis soon after an event; damage effects in harbors on boats, ships, and facilities; tsunami wave-induced forces; damage by tsunami waves to structures on shore; scour/erosion; hazard mitigation; land use planning; zoning; siting, design, construction and maintenance of structures and infrastructure; public awareness and education; distant and local sources; tsunami warning and evacuation programs; tsunami probability and risk criteria. A few references are on "sedimentary signatures" useful in the study of historic and prehistoric tsunamis (paleo-tsunamis. In addition to references specifically on tsunamis, there are references on long water wave and solitary wave theory; wave refraction, diffraction, and reflection; shelf and basin free and forced oscillations (bay and harbor response; seiches; edge waves; Mach- reflection of long water waves ("stem waves"; wave run-up on shore; energy dissipation. All are important in understanding tsunamis, and in hazard mitigation. References are given on subaerial and submarine landslide (and rockfall generated waves in reservoirs, fjords, bays, and ocean; volcano explosive eruptions/collapse; underwater and surface explosions; asteroid impact. This report is in two parts: 1 Bibliographies, books and pamphlets, catalogs, collections, journals and newsletters, maps, organizations, proceedings, videos and photos; 2 Articles, papers, reports listed alphabetically by author.Many papers on the Indian Ocean (Sumatra tsunami of 26 December 2004, were given at the 22nd IUGG International Tsunami Symposium, Chania, Crete, 27-29 June 2005, but had not been published at the date of this report. For the program, see http://www.gein.noa.gr/English/tsunamis.htmThis list of tsunami information sources (115 pp, about 3,300 entries is also available on a diskette, at the Water Resources Center Archives, 410 O'Brien Hall, University of California, Berkeley, CA, 94720-1718. Most of the publications are available in the Water Resources Center Archives or the Earth Sciences Library, University of California, Berkeley, CA.I wish to acknowledge my appreciation of the great help of the staff of the Water Resources Center Archives in finding some difficult to obtain publications; in particular Paul S. Atwood for his help for those on websites and other computer sources. I want to thank John M. Wiegel for his continuous help in searching for sources on websites via computer search-engines.
Robert L. Wiegel
Tsunami sources are intimately linked to geological events. Earthquakes and landslides are shown to be part of a continuum of complicated geological phenomena. Advances in landslide tsunami research will remain coupled with marine geology research. The landslide tsunami hypothesis is shown to have originated in the scientific literature in the early 1900s. Tsunami science has been slow to embrace the hypothesis in part because of the tremendous uncertainity that it introduces into tsunami gne...
Objective: We aimed to explore stakeholder views, attitudes, needs, and expectations regarding likely benefits and risks resulting from increased structuring and coding of clinical information within electronic health records (EHRs). Materials and methods Qualitative investigation in primary and secondary care and research settings throughout the UK. Data were derived from interviews, expert discussion groups, observations, and relevant documents. Participants (n=70) included patients, health...
Morrison, Zoe; Fernando, Bernard; Kalra, Dipak; Cresswell, Kathrin; Sheikh, Aziz
The French Tsunami Warning Center (CENALT) has been in operation since 2012. It is contributing to the North-eastern and Mediterranean (NEAM) tsunami warning and mitigation system coordinated by the United Nations Educational, Scientific, and Cultural Organization, and benefits from data exchange with several foreign institutes. This center is supported by the French Government and provides French civil-protection authorities and member states of the NEAM region with relevant messages for assessing potential tsunami risk when an earthquake has occurred in the Western Mediterranean sea or the Northeastern Atlantic Ocean. To achieve its objectives, CENALT has developed a series of innovative techniques based on recent research results in seismology for early tsunami warning, monitoring of sea level variations and detection capability, and effective numerical computation of ongoing tsunamis.
Schindelé, F.; Gailler, A.; Hébert, H.; Loevenbruck, A.; Gutierrez, E.; Monnier, A.; Roudil, P.; Reymond, D.; Rivera, L.
On August 25th 2007 a tsunami detector installed onboard the multi-parameter observatory GEOSTAR was successfully deployed at 3200 b. s. l. in the Gulf of Cadiz, Portugal. This activity is within the NEAREST EC Project (http://nearest.bo.ismar.cnr.it/ ). Among other deliverables, the NEAREST project will produce and test the basic parts of an operational prototype of a near field tsunami warning system. This system includes an onshore warning centre, based on the geophysical monitoring networks which are already operating, and a tsunami detector deployed on board GEOSTAR at the sea bottom. On land the warning centre is in charge of collecting, integrating, and evaluating data recorded at sea. At the sea bottom data is recorded and processed by an advanced type of tsunami detector which includes: a pressure sensor, a seismometer and two accelerometers. The detector communicates acoustically with a surface buoy in two-way mode. The buoy is equipped with meteo station, GPS and tiltmeter and is connected to a shore station via satellite link. The prototype is designed to operate in tsunami generation areas for detection-warning purpose as well as for scientific measurements. The tsunami detector sends a near real time automatic alert message when a seismic or pressure threshold are exceeded. Pressure signals are processed by the tsunami detection algorithm and the water pressure perturbation caused by the seafloor motion is taken into account. The algorithm is designed to detect small tsunami waves, less than one centimetre, in a very noisy environment. Our objective is to combine a novel approach to the tsunami warning problem, with a study of the coupling between the water column perturbations and sea floor motion, together with the long term monitoring of geophysical, geochemical and oceanographic parameters.
Chierici, F.; Beranzoli, L.; Embriaco, D.; Favali, P.; Marinaro, G.; Monna, S.; Pignagnoli, L.; Zitellini, N.; Bruni, F.; Furlan, F.; Gasparoni, F.
A large number of lakes are surrounded by steep and unstable mountains with slopes prone to failure. As a result, landslides are likely to occur and impact water sitting in closed reservoirs. These rare geological phenomena pose serious threats to dam reservoirs and nearshore facilities because they can generate unexpectedly large tsunami waves. In fact, the tallest wave experienced by contemporary humans occurred because of a landslide in the narrow bay of Lituya in 1958, and five years later, a deadly landslide tsunami overtopped Lake Vajont's dam, flooding and damaging villages along the lakefront and in the Piave valley. If unstable slopes and potential slides are detected ahead of time, inundation maps can be drawn to help people know the risks, and mitigate the destructive power of the ensuing waves. These maps give the maximum wave runup height along the lake's vertical and sloping boundaries, and can be obtained by numerical simulations. Keeping track of the moving shorelines along beaches is challenging in classical Eulerian formulations because the horizontal extent of the fluid domain can change over time. As a result, assuming a solid slide and nonbreaking waves, here we develop a nonlinear shallow-water model equation in the Lagrangian framework to address the problem of transient landslide-tsunamis. In this manner, the shorelines' three-dimensional motion is part of the solution. The model equation is hyperbolic and can be solved numerically by finite differences. Here, a 4th order Runge-Kutta method and a compact finite-difference scheme are implemented to integrate in time and spatially discretize the forced shallow-water equation in Lagrangian coordinates. The formulation is applied to different lake and slide geometries to better understand the effects of the lake's finite lengths and slide's forcing mechanism on the generated wavefield. Specifically, for a slide moving down a plane beach, we show that edge-waves trapped by the shoreline and free-waves moving away from it coexist. On an open coast, these two types of waves would never interact, but because of the lake's finite dimensions, here we show that local inundation height maxima are due to wave superposition on the shoreline. These interactions can be dramatic near the lake's corners. For instance, in a rectangular lake delimited by two opposite and plane beaches and two vertical walls, we find that a landslide tsunami results in an inundation height at a corner 50% larger than anywhere else. The nonlinear and linear models produce different inundation maps, and here we show that maximum wave runups can be increased by up to 56% when nonlinear terms are included.
Couston, L.; Mei, C.; Alam, M.
Oregon Department of Geology and Mineral Industries and Oregon Emergency Management collaborated over the last four years to increase tsunami preparedness for residents and visitors to the Oregon coast. Utilizing support from the National Tsunami Hazards Mitigation Program (NTHMP), new approaches to outreach and tsunami hazard assessment were developed and then applied. Hazard assessment was approached by first doing two pilot studies aimed at calibrating theoretical models to direct observations of tsunami inundation gleaned from the historical and prehistoric (paleoseismic/paleotsunami) data. The results of these studies were then submitted to peer-reviewed journals and translated into 1:10,000-12,000-scale inundation maps. The inundation maps utilize a powerful new tsunami model, SELFE, developed by Joseph Zhang at the Oregon Health & Science University. SELFE uses unstructured computational grids and parallel processing technique to achieve fast accurate simulation of tsunami interactions with fine-scale coastal morphology. The inundation maps were simplified into tsunami evacuation zones accessed as map brochures and an interactive mapping portal at http://www.oregongeology.org/tsuclearinghouse/. Unique in the world are new evacuation maps that show separate evacuation zones for distant versus locally generated tsunamis. The brochure maps explain that evacuation time is four hours or more for distant tsunamis but 15-20 minutes for local tsunamis that are invariably accompanied by strong ground shaking. Since distant tsunamis occur much more frequently than local tsunamis, the two-zone maps avoid needless over evacuation (and expense) caused by one-zone maps. Inundation mapping for the entire Oregon coast will be complete by ~2014. Educational outreach was accomplished first by doing a pilot study to measure effectiveness of various approaches using before and after polling and then applying the most effective methods. In descending order, the most effective methods were: (1) door-to-door (person-to-person) education, (2) evacuation drills, (3) outreach to K-12 schools, (4) media events, and (5) workshops targeted to key audiences (lodging facilities, teachers, and local officials). Community organizers were hired to apply these five methods to clusters of small communities, measuring performance by before and after polling. Organizers were encouraged to approach the top priority, person-to-person education, by developing Community Emergency Response Teams (CERT) or CERT-like organizations in each community, thereby leaving behind a functioning volunteer-based group that will continue the outreach program and build long term resiliency. One of the most effective person-to-person educational tools was the Map Your Neighborhood program that brings people together so they can sketch the basic layout of their neighborhoods to depict key earthquake and tsunami hazards and mitigation solutions. The various person-to-person volunteer efforts and supporting outreach activities are knitting communities together and creating a permanent culture of tsunami and earthquake preparedness. All major Oregon coastal population centers will have been covered by this intensive outreach program by ~2014.
Priest, G. R.; Rizzo, A.; Madin, I.; Lyles Smith, R.; Stimely, L.
While the propagation of tsunamis is well understood and well simulated by numerical models, there are still a number of unanswered questions related to the generation of tsunamis or the subsequent inundation. We review some of the basic generation mechanisms as well as their simulation. In particular, we present a simple and computationally inexpensive model that describes the seabed displacement during an underwater earthquake. This model is based on the finite fault solution for the slip distribution under some assumptions on the kinematics of the rupturing process. We also consider an unusual source for tsunami generation: the sinking of a cruise ship. Then we review some aspects of tsunami run-up. In particular, we explain why the first wave of a tsunami is sometimes less devastating than the subsequent waves. A resonance effect can boost the waves that come later. We also look at a particular feature of the 11 March 2011 tsunami in Japan - the formation of macro-scale vortices - and show that these macr...
Dias, Frédéric; O'Brien, Laura; Renzi, Emiliano; Stefanakis, Themistoklis
To date, the effects of tsunami erosion and deposition have mainly been reported from tropical and temperate climatic zones yet tsunamis are also frequent in polar zones, particularly in fjord settings where they can be generated by landslides. Here we report the geological effects of a landslide-triggered tsunami that occurred on 21st November 2000 in Vaigat, northern Disko Bugt in west Greenland. To characterise the typical features of this tsunami we completed twelve detailed coastal transects in a range of depositional settings: cliff coasts, narrow to moderate width coastal plains, lagoons and a coastal lake. At each setting we completed a detailed map using a laser scanner and DGPS survey. The tsunami deposits were described from closely spaced trenches and, from the lake, by a series of sediment cores . At each setting we examined the sedimentological properties of the deposits, as well as their bulk geochemistry and diatom content. Selected specimens of arctic willow from inundated and non-inundated areas were collected to assess the impact of the event in their growth ring records. Samples of sediments beneath the AD 2000 deposit were studied for 137Cs to confirm the age of the tsunami and to assess the extent of erosion. Offshore sediment samples, modern beach and soils/sediments underlying the AD 2000 tsunami deposits were sampled to determine tsunami deposit sources. The observed tsunami run-up exceeded 20 m next to the tsunami trigger - a rock avalanche at Paatuut - and up to 10 m on the opposite coast of the fjord. The inland inundation distance ranged from several tens of meters to over 300 m. The wave was recorded as far as 180 km away from the source. The tsunami inundated the coast obliquely to the shoreline in all locations studied. The tsunami frequently caused erosion of existing beach ridges whilst erosional niches were formed inland. The tsunami deposits mainly comprise gravels and very coarse sand. They are over 30 cm thick close to the coast and in front of inland scarps. In the most inland parts of the inundation they are often marked only by patches of coarse sand left on the pre-tsunami soil. At several sites we observed boulder deposits, although in many cases they were likely transported as boulders in icebergs. A characteristic feature related to tsunami deposits were "mud pats" - up to 1 m in diameter and about 20 cm thick silty deposits with occasional gravels - which cover the tsunami deposit. They are interpreted as the result of melting of icebergs washed inland by the tsunami. They often occur close to the inundation limit. The mud pats are a characteristic feature for the tsunami deposits in iceberg dominated settings and are unlikely to be left by storms. The results of this study will serve as a guide for further studies of palaeotsunami in the Vaigat region and elsewhere in polar regions. The study was funded by Polish National Science Centre grant No. 2011/01/B/ST10/01553. Fieldwork was supported by the Arctic Station, Disko (Danish Polar Centre). The police at Ilulissat is acknowledged for providing photographic documentation of the tsunami taken one day after the event.
Szczucinski, W.; Rosser, N. J.; Strzelecki, M. C.; Long, A. J.; Lawrence, T.; Buchwal, A.; Chague-Goff, C.; Woodroffe, S.
Full Text Available Based on LANDSAT ETM and Digital Elevation Model (DEM data derived by the Shuttle Radar Topography Mission (SRTM, 2000 of the coastal areas of Northern Venezuela were investigated in order to detect traces of earlier tsunami events. Digital image processing methods used to enhance LANDSAT ETM imageries and to produce morphometric maps (such as hillshade, slope, minimum and maximum curvature maps based on the SRTM DEM data contribute to the detection of morphologic traces that might be related to catastrophic tsunami events. These maps combined with various geodata such as seismotectonic data in a GIS environment allow the delineation of coastal regions with potential tsunami risk. The LANDSAT ETM imageries merged with digitally processed and enhanced SRTM data clearly indicate areas that might be prone by flooding in case of catastrophic tsunami events.
... Safety Food Safety Water Quality Sanitation & Hygiene Diseases & Health Concerns Information for Clinicians Response & Cleanup After a Tsunami Worker Safety After a Flood Pesticide Safety Guidance Epidemiologic Methods for Relief Operations MMWRs ...
The Caribbean has a long history of tsunamis and earthquakes. Over the past 500 years, more than 80 tsunamis have been documented in the region by the NOAA National Geophysical Data Center. Almost 90% of all these historical tsunamis have been associated with earthquakes. Just since 1842, 3510 lives have been lost to tsunamis; this is more than in the Northeastern Pacific for the same time period. With a population of almost 160 million and a heavy concentration of residents, tourists, businesses and critical infrastructure along the Caribbean shores (especially in the northern and eastern Caribbean), the risk to lives and livelihoods is greater than ever before. Most of the countries also have a very high exposure to earthquakes. Given the elevated vulnerability, it is imperative that government officials take steps to mitigate the potentially devastating effects of these events. Nevertheless, given the low frequency of high impact earthquakes and tsunamis, in comparison to hurricanes, combined with social and economic considerations, the needed investments are not made and disasters like the 2010 Haiti earthquake occur. In the absence of frequent significant events, an important driving force for public officials to take action, is the dissemination of scientific studies. When papers of this nature have been published and media advisories issued, public officials demonstrate heightened interest in the topic which in turn can lead to increased legislation and funding efforts. This is especially the case if the material can be easily understood by the stakeholders and there is a local contact. In addition, given the close link between earthquakes and tsunamis, in Puerto Rico alone, 50% of the high impact earthquakes have also generated destructive tsunamis, it is very important that earthquake and tsunami hazards studies demonstrate consistency. Traditionally in the region, earthquake and tsunami impacts have been considered independently in the emergency planning processes. For example, earthquake and tsunami exercises are conducted separately, without taking into consideration the compounding effects. Recognizing this deficiency, the UNESCO IOC Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) which was established in 2005, decided to include the tsunami and earthquake impacts for the upcoming March 20, 2013 regional CARIBE WAVE/LANTEX tsunami exercise. In addition to the tsunami wave heights predicted by the National Weather Service Tsunami Warning Centers in Alaska and Hawaii, the USGS PAGER and SHAKE MAP results for the M8.5 scenario earthquake in the southern Caribbean were also integrated into the manual. Additionally, in recent catastrophic planning for Puerto Rico, FEMA did request the local researchers to determine both the earthquake and tsunami impacts for the same source. In the US, despite that the lead for earthquakes and tsunamis lies within two different agencies, USGS and NOAA/NWS, it has been very beneficial that the National Tsunami Hazard Mitigation Program partnership includes both agencies. By working together, the seismic and tsunami communities can achieve an even better understanding of the hazards, but also foster more actions on behalf of government officials and the populations at risk.
von Hillebrandt-Andrade, C.
Fluid and impact loads and scouring from tsunami inundation creates substantial collapse risk for coastal buildings. An April 2011 survey after the Tohoku Tsunami led by the principal author investigated cases of structural failures, successes and near failures. During the 2011 Tohoku Tsunami, aerial and land-based video cameras captured the inundation at numerous locations along the Tohoku coastline of Japan. Tsunami flow depths and velocities were determined based on analysis of video records and the effects on simple benchmark structures in the flow path. Detailed field measurements and material samples were used to verify critical dimensions and properties of structures. A subsequent National Science Foundation-sponsored survey captured even more detailed LiDAR data of selected structures which was used to validate structural deformations from the structural analysis. The ASCE Structural Engineering Institute will be incorporating tsunami design provisions in the next update of the national load standard, ASCE 7-2016, Minimum Design Loads for Buildings and Other Structures. We will present several relevant case studies of full-scale tsunami loads on structures used to evaluate design provisions being considered for these provisions. The first two authors are also working on the performance-based tsunami design criteria, where a building's performance objective for design is based on the role it plays in the community. Drawing on findings from research and post-tsunami building vulnerability analyses, the authors will discuss how these findings are informing the direction of the forthcoming ASCE 7-2016 chapter on Tsunami Loads and Effects that will be the first national tsunami design provisions applicable for all US states with Pacific Ocean coastlines. During the 2011 Tohoku Tsunami, many thousands of people were saved by taking shelter in multi-story reinforced concrete buildings after the tsunami warning was issued. The first two authors visited a number of these structures that were inundated in the tsunami, and incorporated these lessons in updated provisions for the second edition of FEMA P646, Guidelines for Design of Structures for Vertical Evacuation from Tsunamis (2012). The significant changes to these revised guidelines for new, specially designed and constructed facilities will be explained. Regardless of whether or not a multi-story building is designated as a tsunami evacuation refuge, a sufficiently robust and tall building may offer significant basic life safety protection to occupants. Therefore, with the emergence of new guidelines and code standards, and with expertise in evaluating particular modes of structural failures caused during a tsunami, it will be feasible to design buildings to withstand tsunami events. This is desirable for taller buildings that may serve as refuges, taller buildings that may not be easily evacuated, buildings whose failure may pose a substantial risk to human life, and essential facilities that by necessity of function may exist in the inundated coastal zone.
Chock, G.; Robertson, I.; Carden, L.
This is an update to EGU2011-3094 informing on the progress of the establishment of a National Tsunami Warning Center in Turkey (NTWC-TR) under the UNESCO Intergovernmental Oceanographic Commission - Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas (IOC-ICG/NEAMTWS) initiative. NTWC-TR is integrated into the 24/7 operational National Earthquake Monitoring Center (NEMC) of KOERI comprising 129 BB and 61 strong motion sensors. Based on an agreement with the Disaster and Emergency Management Presidency (DEMP), data from 10 BB stations located in the Aegean and Mediterranean Coast is now transmitted in real time to KOERI. Real-time data transmission from 6 primary and 10 auxiliary stations from the International Monitoring System will be in place in the very near future based on an agreement concluded with the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO) in 2011. In an agreement with a major Turkish GSM company, KOERI is enlarging its strong-motion network to promote real-time seismology and to extend Earthquake Early Warning system countrywide. 25 accelerometers (included in the number given above) have been purchased and installed at Base Transceiver Station Sites in coastal regions within the scope of this initiative. Data from 3 tide gauge stations operated by General Command of Mapping (GCM) is being transmitted to KOERI via satellite connection and the aim is to integrate all tide-gauge stations operated by GCM into NTWC-TR. A collaborative agreement has been signed with the European Commission - Joint Research Centre (EC-JRC) and MOD1 Tsunami Scenario Database and TAT (Tsunami Analysis Tool) are received by KOERI and user training was provided. The database and the tool are linked to SeisComp3 and currently operational. In addition KOERI is continuing the work towards providing contributions to JRC in order to develop an improved database (MOD2), and also continuing work related to the development of its own scenario database using NAMI DANCE Tsunami Simulation and Visualization Software. Further improvement of the Tsunami Warning System at the NTWC-TR will be accomplished through KOERI's participation in the FP-7 Project TRIDEC focusing on new technologies for real-time intelligent earth information management to be used in Tsunami Early Warning Systems. In cooperation with Turkish State Meteorological Service (TSMS), KOERI has its own GTS system now and connected to GTS via its own satellite hub. The system has been successfully utilized during the First Enlarged Communication Test Exercise (NEAMTWS/ECTE1), where KOERI acted as the message provider. KOERI is providing guidance and assistance to a working group established within the DEMP on issues such as Communication and Tsunami Exercises, National Procedures and National Tsunami Response Plan. KOERI is also participating in NEAMTIC (North-Eastern Atlantic and Mediterranean Tsunami Information Centre) Project. Finally, during the 8th Session of NEAMTWS in November 2011, KOERI has announced that NTWC-TR is operational as of January 2012 covering Eastern Mediterranean, Aegean, Marmara and Black Seas and KOERI is also ready to operate as an Interim Candidate Tsunami Watch Provider.
Meral Ozel, N.; Necmioglu, O.; Yalciner, A. C.; Kalafat, D.; Yilmazer, M.; Comoglu, M.; Sanli, U.; Gurbuz, C.; Erdik, M.
Full Text Available Tsunami Information Sources (Robert L. Wiegel, University of California, Berkeley, CA, UCB/HEL 2005-1, 14 December 2005, 115 pages, is available in printed format, and on a diskette. It is also available in electronic format at the Water Resources Center Archives, University of California, Berkeley, CA http:www.lib.berkeley.edu/WRCA/tsunamis.htmland in the International Journal of The Tsunami Society, Science of Tsunami Hazards (Vol. 24, No. 2, 2006, pp 58-171 at http://www.sthjournal.org/sth6.htm.This is Part 2 of the report. It has two components. They are: 1.(Sections A and B. Sources added since the first report, and corrections to a few listed in the first report. 2.(Sections C and D. References from both the first report and this report, listed in two categories:Section C. Planning and engineering design for tsunami mitigation/protection; adjustments to the hazard; damage to structures and infrastructureSection D. Tsunami propagation nearshore; induced oscillations; runup/inundation (flooding and drawdown.
Robert L. Wiegel
The 26 December 2004 Andaman mega tsunami killed about a quarter of a million people worldwide. Since then several significant tsunamis have recurred in this region, including the most recent 25 October 2010 Mentawai tsunami. These tsunamis grimly remind us of the devastating destruction that a tsunami might inflict on the affected coastal communities. There is evidence that tsunamis of similar or higher magnitudes might occur again in the near future in this region. Of particular concern to Malaysia are tsunamigenic earthquakes occurring along the northern part of the Sunda Trench. Further, the Manila Trench in the South China Sea has been identified as another source of potential tsunamigenic earthquakes that might trigger large tsunamis. To protect coastal communities that might be affected by future tsunamis, an effective early warning system must be properly installed and maintained to provide adequate time for residents to be evacuated from risk zones. Affected communities must be prepared and educated in advance regarding tsunami risk zones, evacuation routes as well as an effective evacuation procedure that must be taken during a tsunami occurrence. For these purposes, tsunami risk zones must be identified and classified according to the levels of risk simulated. This paper presents an analysis of tsunami simulations for the South China Sea and the Andaman Sea for the purpose of developing a tsunami risk zone classification map for Malaysia based upon simulated maximum wave heights. ?? 2011 WIT Press.
Teh, S.Y.; Koh, H.-L.; Moh, Y.T.; De Angelis, D. L.; Jiang, J.
Both spatial and spatiotemporal distributions of the sources of tsunamigenic earthquakes of tectonic origin over the last 112 years have been analyzed. This analysis has been made using tsunami databases published by the Institute of Computational Mathematics and Mathematical Geophysics (Siberian Branch, Russian Academy of Sciences) and the National Aeronautics and Space Administration (United States), as well as earthquake catalogs published by the National Earthquake Information Center (United States). It has been found that the pronounced activation of seismic processes and an increase in the total energy of tsunamigenic earthquakes were observed at the beginning of both the 20th (1905-1920) and 21st (2004-2011) centuries. Studying the spatiotemporal periodicity of such events on the basis of an analysis of the two-dimensional distributions of the sources of tectonic tsunamis has made it possible to determine localized latitudinal zones with a total lack of such events (90°-75° N, 45°-90° S, and 35°-25° N) and regions with a periodic occurrence of tsunamis mainly within the middle (65°-35° N and 25°-40° S) and subequatorial (15° N-20° S) latitudes of the Northern and Southern hemispheres. The objective of this work is to analyze the spatiotemporal distributions of sources of tsunamigenic earthquakes and the effect of the periodic occurrence of such events on the basis of data taken from global tsunami catalogs.
Levin, B. W.; Sasorova, E. V.
In the aftermath of a catastrophic tsunami, much is to be learned about tsunami generation and propagation, landscape and ecological changes, and the response and recovery of those affected by the disaster. Knowledge of the impacted area directly helps response and relief personnel in their efforts to reach and care for survivors and for re-establishing community services. First-hand accounts of tsunami-related impacts and consequences also help researchers, practitioners, and policy makers in other parts of the world that lack recent events to better understand and manage their own societal risks posed by tsunami threats. Conducting post-tsunami surveys and disseminating useful results to decision makers in an effective, efficient, and timely manner is difficult given the logistical issues and competing demands in a post-disaster environment. To facilitate better coordination of field-data collection and dissemination of results, a protocol for coordinating post-tsunami science surveys was developed by a multi-disciplinary group of representatives from state and federal agencies in the USA. This protocol is being incorporated into local, state, and federal post-tsunami response planning through the efforts of the Pacific Risk Management ‘Ohana, the U.S. National Tsunami Hazard Mitigation Program, and the U.S. National Plan for Disaster Impact Assessments. Although the protocol was designed to support a coordinated US post-tsunami response, we believe it could help inform post-disaster science surveys conducted elsewhere and further the discussion on how hazard researchers can most effectively operate in disaster environments.
Wilson, Rick I.; Wood, Nathan J.; Kong, Laura; Shulters, Michael V.; Richards, Kevin D.; Dunbar, Paula; Tamura, Gen; Young, Edward J.
Tsunami runup measurements over the periphery of the Pacific Ocean after the devastating Great Japan tsunami of 11 March 2011 showed considerable variation in far-field and near-field impact. This variation of tsunami impact have been attributed to either directivity of the source or by local topographic effects. Directivity arguments alone, however, cannot explain the complexity of the radiated patterns in oceans with trenches and seamounts. Berry (2007, Proc. R. Soc. Lond. A 463, 3055-3071) discovered how such underwater features may concentrate tsunamis into cusped caustics and thus cause large local amplifications at specific focal points. Here, we examine focusing and local amplification, not by considering the effects of underwater diffractive lenses, but by considering the details of the dipole nature of the initial profile, and propose that certain regions of coastline are more at-risk, not simply because of directivity but because typical tsunami deformations create focal regions where abnormal tsunami wave height can be registered (Marchuk and Titov, 1989, Proc. IUGG/IOC International Tsunami Symposium, Novosibirsk, USSR). In this work, we present a new general analytical solution of the linear shallow-water wave equation for the propagation of a finite-crest-length source over a constant depth without any restriction on the initial profile. Unlike the analytical solution of Carrier and Yeh (2005, Comp. Mod. Eng. & Sci. 10(2), 113-121) which was restricted to initial conditions with Gaussian profiles and involved approximation, our solution is not only exact, but also general and allows the use of realistic initial waveform such as N-waves as defined by Tadepalli and Synolakis (1994, Proc. R. Soc. Lond. A 445, 99-112). We then verify our analytical solution for several typical wave profiles, both with the NOAA tsunami forecast model MOST (Titov and Synolakis, 1998, J. Waterw. Port Coast. Ocean Eng. 124(4), 157-171) which is validated and verified through (Synolakis et al., 2008, Pure Appl. Geophys. 165(11-12), 2197-2228), and with a Boussinesq model, to illustrate the role focusing can play for different initial conditions, and to show the robust nature of focusing with respect to dispersion. We also show how the focusing effect might have played a role in the 17 July 1998 Papua New Guinea and 17 July 2006 Java events, and also the 11 March 2011 Great Japan earthquake and tsunami. Our results strongly imply that focusing increases the shoreline amplification of the tsunami.; Schematic of focusing; initial displacement (upper left), wave evolution (upper right, lower left), maximum wave amplitude with focusing (lower right).
Moore, C. W.; Kanoglu, U.; Titov, V. V.; Aydin, B.; Spillane, M. C.; Synolakis, C. E.
The devastating earthquake and tsunami of December 26, 2004 has greatly increased recognition of the need for water level data both from the coasts and the deep-ocean. In 2006, the National Oceanic and Atmospheric Administration (NOAA) completed a Tsunami Data Management Report describing the management of data required to minimize the impact of tsunamis in the United States. One of the major gaps defined in this report is the access to global coastal water level data. NOAA's National Geophysical Data Center (NGDC) and National Climatic Data Center (NCDC) are working cooperatively to bridge this gap. NOAA relies on a network of global data, acquired and processed in real-time to support tsunami detection and warning, as well as high-quality global databases of archived data to support research and advanced scientific modeling. In 2005, parties interested in enhancing the access and use of sea level station data united under the NOAA NCDC's Integrated Data and Environmental Applications (IDEA) Center's Pacific Region Integrated Data Enterprise (PRIDE) program to develop a distributed metadata system describing sea level stations (Kari et. al., 2006; Marra et.al., in press). This effort started with pilot activities in a regional framework and is targeted at tsunami detection and warning systems being developed by various agencies. It includes development of the components of a prototype sea level station metadata web service and accompanying Google Earth-based client application, which use an XML-based schema to expose, at a minimum, information in the NOAA National Weather Service (NWS) Pacific Tsunami Warning Center (PTWC) station database needed to use the PTWC's Tide Tool application. As identified in the Tsunami Data Management Report, the need also exists for long-term retention of the sea level station data. NOAA envisions that the retrospective water level data and metadata will also be available through web services, using an XML-based schema. Five high-priority metadata requirements identified at a water level workshop held at the XXIV IUGG Meeting in Perugia will be addressed: consistent, validated, and well defined numbers (e.g. amplitude); exact location of sea level stations; a complete record of sea level data stored in the archive; identifying high-priority sea level stations; and consistent definitions. NOAA's National Geophysical Data Center (NGDC) and co-located World Data Center for Solid Earth Geophysics (including tsunamis) would hold the archive of the sea level station data and distribute the standard metadata. Currently, NGDC is also archiving and distributing the DART buoy deep-ocean water level data and metadata in standards based formats. Kari, Uday S., John J. Marra, Stuart A. Weinstein, 2006 A Tsunami Focused Data Sharing Framework For Integration of Databases that Describe Water Level Station Specifications. AGU Fall Meeting, 2006. San Francisco, California. Marra, John, J., Uday S. Kari, and Stuart A. Weinstein (in press). A Tsunami Detection and Warning-focused Sea Level Station Metadata Web Service. IUGG XXIV, July 2-13, 2007. Perugia, Italy.
Stroker, K. J.; Marra, J.; Kari, U. S.; Weinstein, S. A.; Kong, L.
Deep-sea tsunami measurements play a major role in understanding the physics of tsunami wave generation and propagation, and in the creation of an effective tsunami warning system. The paper provides an overview of the history of tsunami recording in the open ocean from the beginning (about 50 years ago) to the present day. It describes modern tsunami monitoring systems, including the Deep-ocean Assessment and Reporting of Tsunamis (DART), innovative Japanese bottom cable projects, and the NEPTUNE-Canada geophysical bottom observatory. The specific peculiarities of seafloor longwave observations in the deep ocean are discussed and compared with those recorded in coastal regions. Tsunami detection in bottom presure observations is exemplified based on analysis of distant (22000 km) records of the 2004 Sumatra tsunami in the northeastern Pacific.
Rabinovich, A. B.
The December 2004 Indian Ocean tsunami was the worst tsunami disaster in the world's history with more than 200,000 casualties. This disaster was attributed to giant size (magnitude M ~ 9, source length >1000 km) of the earthquake, lacks of expectation of such an earthquake, tsunami warning system, knowledge and preparedness for tsunamis in the Indian Ocean countries. In the last ten years, seismology and tsunami sciences as well as tsunami disaster risk reduction have significantly developed. Progress in seismology includes implementation of earthquake early warning, real-time estimation of earthquake source parameters and tsunami potential, paleoseismological studies on past earthquakes and tsunamis, studies of probable maximum size, recurrence variability, and long-term forecast of large earthquakes in subduction zones. Progress in tsunami science includes accurate modeling of tsunami source such as contribution of horizontal components or "tsunami earthquakes", development of new types of offshore and deep ocean tsunami observation systems such as GPS buoys or bottom pressure gauges, deployments of DART gauges in the Pacific and other oceans, improvements in tsunami propagation modeling, and real-time inversion or data assimilation for the tsunami warning. These developments have been utilized for tsunami disaster reduction in the forms of tsunami early warning systems, tsunami hazard maps, and probabilistic tsunami hazard assessments. Some of the above scientific developments helped to reveal the source characteristics of the 2011 Tohoku earthquake, which caused devastating tsunami damage in Japan and Fukushima Dai-ichi Nuclear Power Station accident. Toward tsunami disaster risk reduction, interdisciplinary and trans-disciplinary approaches are needed for scientists with other stakeholders.
The 1946 Aleutian earthquake was a typical tsunami earthquake which generated abnormally larger tsunami than expected from its seismic waves. Previously, Johnson and Satake (1997) estimated the fault model of this earthquake using the tsunami waveforms observed at tide gauges. However, they did not model the second pulse of the tsunami at Honolulu although that was much larger than the first pulse. In this paper, we numerically computed the tsunami waveforms using the linear Boussinesq...
Tanioka, Y.; Seno, T.
Full Text Available Abstract Background Aboriginal injection drug users are the fastest growing group of new Human Immunodeficiency Virus cases in Canada. However, there remains a lack of comprehensive harm reduction services available to First Nation persons, particularly for First Nation people dwelling in rural and reserve communities. This paper reports findings from an exploratory study of current harm reduction practices in First Nation communities. The purpose of this study was to provide an overview of the availability and content of current harm reduction practices, as well as to identify barriers and opportunities for implementing these services in First Nation communities. Methods Key informant interviews were conducted with 13 addictions service providers from the province of British Columbia, Canada. Results Participants identified barriers to these services such as community size and limited service infrastructure, lack of financial resources, attitudes towards harm reduction services and cultural differences. Conclusion It was recommended that community education efforts be directed broadly within the community before establishing harm reduction services and that the readiness of communities be assessed.
Tsunamis are among the most terrifying natural hazards known to man and have been responsible for tre-mendous loss of life and property throughout history. In this paper by means of dimensional analysis, important non-dimensional groups in Tsunamis was studied and an equation to calculate the power of tsunamis was obtained. Also by this method and using tsunami basic physics, the height of waves near the coastline was estimated and results were compared by reported values.
Mass transport events, such as those from submarine landslides, volcanic flank collapse at convergent margins and on oceanic islands, and subaerial failure are reviewed and found to be all potential tsunami sources. The intensity and frequency of the tsunamis resulting is dependent upon the source. Most historical records are of devastating tsunamis from volcanic collapse at convergent margins. Although the database is limited, tsunamis sourced from submarine landslides and collapse on oceani...
Tappin, D. R.
This portal provides access to information on United States Geological Survey (USGS) research and resources on tsunamis and earthquakes. Materials include news and events in USGS tsunami research, an overview of the program, and basic information on the life of a tsunami. There are also links to individual research projects. The site also features an extensive set of tsunami animations of real and hypothetical events, and links to VRML models of real and hypothetical events.
Full Text Available The coasts of Turkey have been hit by tsunamis in the past. The first national earthquake-tsunami catalogues were compiled in the early 1980s while the most up-to-date tsunami catalogues are mainly the products of recent European projects. The EU projects GITEC and GITEC-TWO (Genesis and Impact of Tsunamis on the European Coasts and TRANSFER (Tsunami Risk ANd Strategies For the European Region have added important contributions in establishing and developing unified criteria for tsunami parameterisation, standards for the quality of the data, the data format and the database general architecture. On the basis of these new aspects and based on recent marine geophysical data, tsunamigenic earthquakes, tsunami intensities and their reliability have been revised. The current version of the database contains 134 events, most of which have affected the Turkish coasts seriously during the last 3500 years. The reliability index of 76 events was "probable" and "definite", so that they could be used for assessment of the risk along the Turkish coastal region and for implementation of prevention policies.
Full Text Available Hawai`i has a long, though sporadic history of deadly tsunami attacks.Since the 1946 tsunami disaster the State of Hawaii has developed increasingly sophisticated and effective mitigation strategies. The evolution and operation of these strategies is described in this paper. Tsunamis will no longer be Hawai`i’s deadliest natural hazard.
George D. Curtis
The natural disaster of the Boxing Day Tsunami of 2004 was followed by an information catastrophe. Crucial early warning information could not be delivered to the communities under imminent threat, resulting in over 240,000 casualties in 14 countries. This tragedy sparked the development of a new generation of integrated modular Tsunami Early Warning Systems (TEWS). While significant advances were accomplished in the past years, recent events, like the Chile 2010 and the Tohoku 2011 tsunami demonstrate that the key technical challenge for Tsunami Early Warning research on the supranational scale still lies in the timely issuing of status information and reliable early warning messages in a proven workflow. A second challenge stems from the main objective of the Intergovernmental Oceanographic Commission of UNESCO (IOC) Tsunami Programme, the integration of national TEWS towards ocean-wide networks: Each of the increasing number of integrated Tsunami Early Warning Centres has to cope with the continuing evolution of sensors, hardware and software while having to maintain reliable inter-center information exchange services. To avoid future information catastrophes, the performance of all components, ranging from individual sensors, to Warning Centers within their particular end-to-end Warning System Environments, and up to federated Systems of Tsunami Warning Systems has to be regularly validated against defined criteria. Since 2004, GFZ German Research Centre for Geosciences (GFZ) has built up expertise in the field of TEWS. Within GFZ, the Centre for GeoInformation Technology (CeGIT) has focused its work on the geoinformatics aspects of TEWS in two projects already, being the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS). This activity is continued in the TRIDEC project (Collaborative, Complex, and Critical Decision Processes in Evolving Crises) funded under the European Union's seventh Framework Programme (FP7). TRIDEC focuses on real-time intelligent information management in Earth management and its long-term application: The technical development is based on mature system architecture models and industry standards. The use of standards already applies to the operation of individual TRIDEC reference installations and their interlinking into an integrated service infrastructure for supranational warning services. This is a first step towards best practices and service lifecycles for Early Warning Centre IT service management, including Service Level Agreements (SLA) and Service Certification. While on a global scale the integration of TEWS progresses towards Systems of Systems (SoS), there is still an absence of accredited and reliable certifications for national TEWS or regional Tsunami Early Warning Systems of Systems (TEWSoS). Concepts for TEWS operations have already been published under the guidance of the IOC, and can now be complemented by the recent research advances concerning SoS architecture. Combined with feedback from the real world, such as the NEAMwave 2012 Tsunami exercise in the Mediterranean, this can serve as a starting point to formulate initial requirements for TEWS and TEWSoS certification: Certification activities will cover the establishment of new TEWS and TEWSoS, and also both maintenance and enhancement of existing TEWS/TEWSoS. While the IOC is expected to take a central role in the development of the certification strategy, it remains to be defined which bodies will actually conduct the certification process. Certification requirements and results are likely to become a valuable information source for various target groups, ranging from national policy decision makers, government agency planners, national and local government preparedness officials, TWC staff members, Disaster Responders, the media and the insurance industry.
Löwe, Peter; Wächter, Jochen; Hammitzsch, Martin
Full Text Available The empirical research presented in this paper focuses on concepts and perceptions of European politics and citizenship which are expressed by students and teachers in secondary schools. The qualitative study is based on semi-standardized interviews, written surveys, and classroom research (video transcripts, observation records. The results suggest that many young people are amenable towards transnational patterns of identity and they tend to combine pragmatic-optimistic expectations with European Union citizenship. Many of the students interviewed seem willing to adapt themselves to a larger European environment. However, many of the teachers voiced ambivalent notions while expressing veiled scepticism, although they rarely expressed open criticism based on their own fears towards political developments in a unified Europe. The classroom research shows that in the examined civic education lessons, the everyday concepts of students are seldom questioned and sparsely developed towards social-science-based explanatory models. Sometimes even misleading concepts are enforced in classroom interaction instead of being clarified by the development of adequate categories and models.
Full Text Available An innovative newly developed modular and standards based Decision Support System (DSS is presented which forms part of the German Indonesian Tsunami Early Warning System (GITEWS. The GITEWS project stems from the effort to implement an effective and efficient Tsunami Early Warning and Mitigation System for the coast of Indonesia facing the Sunda Arc along the islands of Sumatra, Java and Bali. The geological setting along an active continental margin which is very close to densely populated areas is a particularly difficult one to cope with, because potential tsunamis' travel times are thus inherently short. National policies require an initial warning to be issued within the first five minutes after an earthquake has occurred. There is an urgent requirement for an end-to-end solution where the decision support takes the entire warning chain into account. The system of choice is based on pre-computed scenario simulations and rule-based decision support which is delivered to the decision maker through a sophisticated graphical user interface (GUI using information fusion and fast information aggregation to create situational awareness in the shortest time possible. The system also contains risk and vulnerability information which was designed with the far end of the warning chain in mind – it enables the decision maker to base his acceptance (or refusal of the supported decision also on regionally differentiated risk and vulnerability information (see Strunz et al., 2010. While the system strives to provide a warning as quickly as possible, it is not in its proper responsibility to send and disseminate the warning to the recipients. The DSS only broadcasts its messages to a dissemination system (and possibly any other dissemination system which is operated under the responsibility of BMKG – the meteorological, climatological and geophysical service of Indonesia – which also hosts the tsunami early warning center. The system is to be seen as one step towards the development of a "system of systems" enabling all countries around the Indian Ocean to have such early warning systems in place. It is within the responsibility of the UNESCO Intergovernmental Oceonographic Commission (IOC and in particular its Intergovernmental Coordinating Group (ICG to coordinate and give recommendations for such a development. Therefore the Decision Support System presented here is designed to be modular, extensible and interoperable (Raape et al., 2010.
The Standardized Computer Analysis for Licensing Evaluation (SCALE) code system developed at Oak Ridge National Laboratory (ORNL) includes Tools for Sensitivity and Uncertainty Analysis Methodology Implementation (TSUNAMI). The TSUNAMI code suite can quantify the predicted change in system responses, such as keff, reactivity differences, or ratios of fluxes or reaction rates, due to changes in the energy-dependent, nuclide-reaction-specific cross-section data. Where uncertainties in the neutron cross-section data are available, the sensitivity of the system to the cross-section data can be applied to propagate the uncertainties in the cross-section data to an uncertainty in the system response. Uncertainty quantification is useful for identifying potential sources of computational biases and highlighting parameters important to code validation. Traditional validation techniques often examine one or more average physical parameters to characterize a system and identify applicable benchmark experiments. However, with TSUNAMI correlation coefficients are developed by propagating the uncertainties in neutron cross-section data to uncertainties in the computed responses for experiments and safety applications through sensitivity coefficients. The bias in the experiments, as a function of their correlation coefficient with the intended application, is extrapolated to predict the bias and bias uncertainty in the application through trending analysis or generalizedn through trending analysis or generalized linear least squares techniques, often referred to as 'data adjustment.' Even with advanced tools to identify benchmark experiments, analysts occasionally find that the application models include some feature or material for which adequately similar benchmark experiments do not exist to support validation. For example, a criticality safety analyst may want to take credit for the presence of fission products in spent nuclear fuel. In such cases, analysts sometimes rely on 'expert judgment' to select an additional administrative margin to account for gap in the validation data or to conclude that the impact on the calculated bias and bias uncertainty is negligible. As a result of advances in computer programs and the evolution of cross-section covariance data, analysts can use the sensitivity and uncertainty analysis tools in the TSUNAMI codes to estimate the potential impact on the application-specific bias and bias uncertainty resulting from nuclides not represented in available benchmark experiments. This paper presents the application of methods described in a companion paper.
The Tools for Sensitivity and Uncertainty Analysis Methodology Implementation (TSUNAMI) software developed at Oak Ridge National Laboratory (ORNL) as part of the Scale code system provide unique methods for code validation, gap analysis, and experiment design. For TSUNAMI analysis, sensitivity data are generated for each application and each existing or proposed experiment used in the assessment. The validation of diverse sets of applications requires potentially thousands of data files to be maintained and organized by the user, and a growing number of these files are available through the International Handbook of Evaluated Criticality Safety Benchmark Experiments (IHECSBE) distributed through the International Criticality Safety Benchmark Evaluation Program (ICSBEP). To facilitate the use of the IHECSBE benchmarks in rigorous TSUNAMI validation and gap analysis techniques, ORNL generated SCALE/TSUNAMI sensitivity data files (SDFs) for several hundred benchmarks for distribution with the IHECSBE. For the 2010 edition of IHECSBE, the sensitivity data were generated using 238-group cross-section data based on ENDF/B-VII.0 for 494 benchmark experiments. Additionally, ORNL has developed a quality assurance procedure to guide the generation of Scale inputs and sensitivity data, as well as a graphical user interface to facilitate the use of sensitivity data in identifying experiments and applying them in validation studies.
Rearden, Bradley T [ORNL; Reed, Davis Allan [ORNL; Lefebvre, Robert A [ORNL; Mueller, Don [ORNL; Marshall, William BJ J [ORNL
The objective of this study is to present a model for the short-term and long-term tsunami forecast for Galapagos Islands. For both cases the ComMIT/MOST(Titov,et al 2011) numerical model and methodology have been used. The results for the short-term model has been compared with the data from Lynett et al, 2011 surveyed from the impacts of the March/11 in the Galapagos Islands. For the case of long-term forecast, several scenarios have run along the Pacific, an extreme flooding map is obtained, the method is considered suitable for places with poor or without tsunami impact information, but under tsunami risk geographic location.
The 11 March 2011, Mw 9.0 Great East Japan Earthquake, already among the most destructive earthquakes in modern history, emanated from a fault rupture that extended an estimated 500 km along the Pacific coast of Honshu. This earthquake is the fourth among five of the strongest temblors since AD 1900 and the largest in Japan since modern instrumental recordings began 130 years ago. The earthquake triggered a huge tsunami, which invaded the seaside areas of the Pacific coast of East Japan, causing devastating damages on the coast. Artificial structures were destroyed and planted forests were thoroughly eroded. Inrush of turbulent flows washed backshore areas and dunes. Coastal materials including beach sand were transported onto inland areas by going-up currents. Just after the occurrence of the tsunami, we started field investigation of measuring thickness and distribution of sediment layers by the tsunami and the inundation depth of water in Sendai plain. Ripple marks showing direction of sediment transport were the important object of observation. We used a soil auger for collecting sediments in the field, and sediment samples were submitted for analyzing grain size and interstitial water chemistry. Satellite images and aerial photographs are very useful for estimating the hydrogeological effects of tsunami inundation. We checked the correspondence of micro-topography, vegetation and sediment covering between before and after the tsunami. The most conspicuous phenomenon is the damage of pine forests planted in the purpose of preventing sand shifting. About ninety-five percent of vegetation coverage was lost during the period of rapid currents changed from first wave. The landward slopes of seawalls were mostly damaged and destroyed. Some aerial photographs leave detailed records of wave destruction just behind seawalls, which shows the occurrence of supercritical flows. The large-scale erosion of backshore behind seawalls is interpreted to have been caused by supercritical flows, resulting in the loss of landward seawall slopes. Such erosion was also observed at landward side of footpath between rice fields. The Sendai plain was subjected just after the main shock of the earthquake. Seawater inundation resulting from tsunami run-up lasted two months. The historical document Sandai-jitsuroku, which gives a detailed history of all of Japan, describes the Jogan earthquake and subsequent tsunami which have attacked Sendai plain in AD 869. The document describes the prolonged period of flooding, and it is suggested that co-seismic subsidence of the plain took place. The inundation area of the Jogan tsunami estimated by the distribution of tsunami deposit mostly overlaps with that of the 3.11 tsunami. Considering the very similarity of seismic shocks between the both, we interpreted the Great East Japan Earthquake Tsunami is the second coming of the Jogan Earthquake Tsunami.
Iijima, Y.; Minoura, K.; Hirano, S.; Yamada, T.
Full Text Available SciELO Chile | Language: Spanish Abstract in spanish El territorio chileno cuenta con alrededor de 80.000 km de costa considerando el territorio insular, un dato relevante al momento de considerar la ocurrencia de un tsunami. Las autoridades chilenas, conscientes de este extenso territorio marítimo, han desarrollado un sistema de alerta de tsunami com [...] o una responsabilidad estatal y han depositado su control a la oficina nacional de emergencia – ministerio del interior (ONEMI) y en el servicio hidrográfico y oceanográfico de la armada de Chile (SHOA). En este artículo hemos realizado experiencias con el objetivo de activar los sistemas de advertencias generando eventos telúricos ficticios y/o eventos telúricos históricos capaces de desatar eventos de tsunami. También se ha propuesto una hipótesis de trabajo que permita, a través de los procedimientos establecidos por ley de la República de Chile, monitorear los tiempos de respuestas de los organismos estatales. Nuestro trabajo de investigación entrega resultados que nos permiten afirmar que existen zonas para eventos hipotéticos que podrían generar tsunamis a los cuales el sistema de alerta no sería eficiente en reaccionar. Para llevar a cabo esta investigación hemos utilizado un software llamado SLAT, basado en ecuaciones simplificadas de propagación de una onda de tsunami que nos permite obtener resultados rápidos y además hemos sometido a prueba el sistema con datos oficiales en los cuales se ha demostrado que el sistema de alerta no fue capaz de reaccionar al evento Atico 8,4 M. ocurrido en Perú. Abstract in english The Chilean territory has an extensive coastline -about 80.000 km of coast including the territory of its islands – which is an important fact to consider in the event of the occurrence of a tsunami. The Chilean authorities, fully aware of the vast maritime territory, have developed a tsunami warnin [...] g system. This system constitutes a state responsibility, and its control has been entrusted to the national emergency office - ministry of interior (ONEMI) and hydrographic and oceanographic service of Chilean navy (SHOA). This article deals with experiences carried out in order to activate the warning systems, generating fictional telluric events and / or historical telluric events capable of triggering tsunami occurrences. It also proposes a working hypothesis that will allow monitoring the response of the state agencies, through the procedures established by law in the Republic of Chile. Our research delivers results that allow us to affirm that there are areas for hypothetical events that could generate tsunamis in which the To carry out this research we have used a software called STLAT based on simplified equations of the propagation of a tsunami wave, which has allowed us to get quick results. We have also carried out tests with official data which have shown that the alarm system was not able to respond appropriately to the 8.4 M Atico event that occurred in Peru in 2001.
Gabriel, Alvarez; Jorge, Ramirez; Lorena, Paredes; Miguel, Canales.
This paper considers a theoretical basement for a Poissonian probability model for tsunami run-up heights, with emphasis on the tsunami recurrence function. It is shown that the tsunami recurrence function of a general type contains at least two scale parameters: asymptotic frequency of big tsunamis f related to the considered region and characteristic tsunami height H* for the considered location in the region. A method for the correct statistical evaluation of the parameters f and H*, and their variations, using observational data from tsunami catalogues, is created. The paper considers some theoretical and applied problems related to the tsunami recurrence function, an example of a two-parameter tsunami hazard map, and also the problem of probabilistic tsunami hazard estimation.
The threat of tsunamis and tsunami-like waves hitting the eastern United States is very real despite a general impression to the contrary. We have cataloged 40 tsunamis and tsunami-like waves that have occurred in the eastern United States since 1600. Tsunamis were generated from such events as the 1755 Queen Anne’s earthquake, the Grand Banks event of 1929, the Charleston earthquake of 1886, and the New Madrid earthquakes of 1811-1812. The Queen Anne tsunami was observed as far away as St....
Lander, James F.; Whiteside, Lowell S.; Lockridge, Patricia A.
The tsunami generated by the 1755.01.11 earthquake affected mainly the coasts of the Iberian Peninsula and Northwest Morocco and was observed all over the North Atlantic coasts. The catastrophic dimensions of that phenomenon had a tremendous impact on the city of Lisbon and on several villages along the south coast of Portugal. The earthquake was felt all over Europe and the seismic intensity was estimated as X-XI (Mercalli Intensity Scale) at Lisbon and Southwest Portugal (Cape S. Vicente). The most destructive waves were observed along the coast of Portugal, specially in Lisbon, in the area of the S. Vicente Cape, along the Gulf of Cadiz and Northwest Morocco. Throughout historic times, earthquakes have periodically affected the city of Lisbon causing severe damage and casualties. In spite of that, the city kept growing, so the extension of damage and the loss of human lives in 1755, was quite impressive. The down town of Lisbon was flooded by the rising of the waters of the river Tagus and most historical documents reported waves of 6 m height. At Cape S. Vicente (Southwest Portugal) the run-up height, evaluated from historical data, is greater than 15 m. The eye witness accounts from Spain and Morocco reported wave heights greater than 10 m and large flooded areas along the Gulf of Cadiz and in several harbours in Morocco, e.g. Safi and Agadir. In the city of Lisbon, the number of casualties due exclusively to the tsunami, is estimate around 900, and the penetration of the waters is evaluated to be 250 m. Most of the available literature concerning the 1755 earthquake is based on the compilation of Pereira de Sousa (1919) and, sometimes, incorporates both well established historical records and non reliable information. As the 1755 event evaluation is crucial to a quantitative approach of the tsunami hazard and risk assessment in Portugal, a new examination of the historical records was needed before the establishment of reliable tsunami parameters that can be used both in numerical models of tsunami propagation and in geodynamic studies. In this paper, we present a new compilation of almost all the available historical data from the countries affected by the tsunami. In the analysis of these records, the following tsunami parameters are inferred: travel time, polarity of the first movement, maximum run-up height, period, number of waves, duration of the sea disturbance and extent of flooding.
Baptista, M. A.; Heitor, S.; Miranda, J. M.; Miranda, P.; Victor, L. Mendes
Full Text Available A feasibility study to develop a tsunami alert system for Mexican earthquakes, using broadband seismograms from the Na-tional Seismological Service, is currently under way. A first step in this direction is a revision of the Mexican tsunami catalogs. In these catalogs, one of the largest tsunamis of this century is reported in the Port of Zihuatanejo and has been related to an earthquake which occurred on November 16, 1925. This earthquake was located at a distance of about 600 km from Zihuatanejo and had a surface-wave magnitude, Ms, of 7.0. In developing a tsunami alert system, it is important to know if the tsunami was indeed related to the earthquake of 1925. In this note we examine available evidence and find that the tsunami was not related to the earthquake. There is no evidence of a local earthquake near Zihuatanejo which may have resulted in the tsunami. We con-clude that the tsunami was either caused by slumping of the sea floor near Zihuatanejo or by a meteorological phenomenon in the region.
This study explores the practical sense of talent among top-level football coaches in Denmark, and aims to identify specific structures of the coaches' expert knowledge related to talent identification. The theoretical foundation of the study is Pierre Bourdieu's theoretical framework, in particular the concept of practical sense. The data compile from eight biographical, in-depth interviews with Danish national youth team football coaches. The interviews are analyzed through a process of coding and recoding. Thematic cross-case analyses as well as purposeful selected single-case analyses are used to explore the focus area. The results are grouped in three major themes, which characterize core elements of the coaches' practical sense: 1) visual experience and pattern recognition, 2) recognition of individual paths and personal styles, and 3) a model of top-level football coaches' classificatory schemes. Conclusively, the study supports the theory that talent identification in top-level football is strongly connected to the coach's practical sense of the game and taste for football talents. Furthermore, the study points at the importance of being aware of the person "behind" the coach, given that his practical sense will be identifying the future talents.
Christensen, Mette Krogh
Previously in geophysics, only three heat transport processes have been considered: conduction, radiation, and convection or, more generally, bouyancy-driven mass transport. As a consequence of whole-Earth decompression dynamics, I add a fourth, called mantle decompression thermal-tsunami, which may emplace heat at the base of the crust from a heretofore unanticipated source.
Herndon, J M
Full Text Available A nonlinear nested model for mudslide-induced tsunamis is proposed in which three phases of the life of the wave, i.e. the generation, far-field propagation and costal run-up are described by means of different mathematical models, that are coupled through appropriate matching procedures. The generation and run-up dynamics are simulated through a nonlinear shallow-water model with movable lateral boundaries: in the generation region two active layers are present, the lower one describing the slide descending on a sloping topography. For the intermediate phase, representing wave propagation far from the generation region, the hydrostatic assumption is not assumed as appropriate in general and, therefore, a nonlinear model allowing for weak phase dispersion, namely a Kadomtsev-Petviashvili equation, is used. This choice is made in order to assess the relevance of dispersive features such as solitary waves and dispersive tails. It is shown that in some realistic circumstances dispersive mudslide-induced tsunami waves can be produced over relatively short, distances. In such cases the use of a hydrostatic model throughout the whole tsunami history turns out to give erroneous results. In particular, when solitary waves are generated during the tsunami propagation in the open sea, the resulting run-up process yields peculiar wave forms leading to amplified coastal inundations with respect to a mere hydrostatic context.
The 29 September 2009 Samoa tsunami provided an unexpected exercise for the NOAA's tsunami forecast system, undergoing operational testing at U.S. Tsunami Warning Centers (TWCs). Both TWCs and staff of the Pacific Marine Environmental Laboratory exercised the forecast system to provide tsunami prediction for the Pacific U.S. coastal communities where forecast models have already been developed. The forecast model from a tsunameter-constrained tsunami source, giving the U.S. coastlines more than three and half hours of lead time to respond to the approaching tsunami waves. Even with this unusual and complex earthquake source, the forecast provided required accuracy for important emergency management decisions. During the event, a high-resolution inundation model was quickly developed to compute the tsunami inundation in Samoa Islands - particularly in Tutuila Island. This allowed for the first test of the real-time inundation forecast capability of the system. In addition, the model inundation estimates provided valuable guidance for disaster recovery activities and for the post-tsunami survey guidance. The results illustrate recent improvements and new capabilities of the tsunami forecast system. The problems and lessons learned for both far-field and local tsunami forecast will be discussed.
Titov, Vasily V.; Chamberlin, Chris; Wei, Yong; Moore, Christopher; Uslu, Burak; Kanoglu, Utku
Chile has records of recurring tsunamis. This is confirmed by its geological evidences, long historical records and instrumental data. However, tsunamis were always an underestimated hazard. In 2010 its coasts were affected by a large near-field tsunami and in 2011 for a far-field tsunami generated in Japan, confirming the high vulnerability of coastal communities. Both events had different magnitudes and impacts on coastal areas. The near-field tsunami was generated by an earthquake (Mw 8.8) that occurred on the 27th of February 2010, the waves arrived at the coast in a few minutes and mostly impacted small coastal communities located within the rupture area, there were 156 victims and 25 missing. While the far-field tsunami was generated by a giant earthquake (Mw 9) that occurred on the 11th of March 2011 in Japan, arriving their first waves on the coast of Chile twenty one hours later, displacing thousands of people to high ground. These two recent events have resulted in advances in tsunami hazard mitigation, mainly in the localities that were affected by both events, incorporating the tsunami risk and the emergency management in territorial planning. Example of this is the consideration of risk based on worst case scenarios, design and assessment of mitigation scenarios (e.g. tsunami forest, mitigation parks, dikes and fills) using tsunami modeling and land use policies more rigorous. This research is supported by Fondecyt 11090210.
Lagos, M.; Arenas, F.; Lillo, I.; Tamburini, L.
Following the catastrophic loss of life from the December 26, 2004, Sumatra-Andaman Islands earthquake and tsunami, the U.S. Government appropriated funds to improve monitoring along a major portion of vulnerable coastal regions in the Caribbean Sea, the Gulf of Mexico, and the Atlantic Ocean. Partners in this project include the United States Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the Puerto Rico Seismic Network (PRSN), the Seismic Research Unit of the University of the West Indies, and other collaborating institutions in the Caribbean region. As part of this effort, the USGS is coordinating with Caribbean host nations to design and deploy nine new broadband and strong-motion seismic stations. The instrumentation consists of an STS-2 seismometer, an Episensor accelerometer, and a Q330 high resolution digitizer. Six stations are currently transmitting data to the USGS National Earthquake Information Center, where the data are redistributed to the NOAA's Tsunami Warning Centers, regional monitoring partners, and the IRIS Data Management Center. Operating stations include: Isla Barro Colorado, Panama; Gun Hill Barbados; Grenville, Grenada; Guantanamo Bay, Cuba; Sabaneta Dam, Dominican Republic; and Tegucigalpa, Honduras. Three additional stations in Barbuda, Grand Turks, and Jamaica will be completed during the fall of 2007. These nine stations are affiliates of the Global Seismographic Network (GSN) and complement existing GSN stations as well as regional stations. The new seismic stations improve azimuthal coverage, increase network density, and provide on-scale recording throughout the region. Complementary to this network, NOAA has placed Deep-ocean Assessment and Reporting of Tsunami (DART) stations at sites in regions with a history of generating destructive tsunamis. Recently, NOAA completed deployment of 7 DART stations off the coasts of Montauk Pt, NY; Charleston, SC; Miami, FL; San Juan, Puerto Rico; New Orleans, LA; and Bermuda as part of the U.S. tsunami warning system expansion. DART systems consist of an anchored seafloor pressure recorder (BPR) and a companion moored surface buoy for real-time communications. The new stations are a second-generation design (DART II) equipped with two- way satellite communications that allow NOAA's Tsunami Warning Centers to set stations in event mode in anticipation of possible tsunamis or retrieve the high-resolution (15-s intervals) data in one-hour blocks for detailed analysis. Combined with development of sophisticated wave propagation and site-specific inundation models, the DART data are being used to forecast wave heights for at-risk coastal communities. NOAA expects to deploy a total of 39 DART II buoy stations by 2008 (32 in the Pacific and 7 in the Atlantic, Caribbean and Gulf regions). The seismic and DART networks are two components in a comprehensive and fully-operational global observing system to detect and warn the public of earthquake and tsunami threats. NOAA and USGS are working together to make important strides in enhancing communication networks so residents and visitors can receive earthquake and tsunami watches and warnings around the clock.
Gee, L.; Green, D.; McNamara, D.; Whitmore, P.; Weaver, J.; Huang, P.; Benz, H.
Ten years later, the Indian Ocean tsunami of 26 December 2004 still looms large in efforts to reduce tsunami risk. The disaster has spurred worldwide advances in tsunami detection and warning, risk assessment, and awareness [Satake, 2014].
Kakar, Din Mohammad; Naeem, Ghazala; Usman, Abdullah; Hasan, Haider; Lohdi, Hira Ashfaq; Srinivasalu, Seshachalam; Andrade, Vanessa; Rajendran, C. P.; Beni, Abdolmajid Naderi; Hamzeh, Mohammad Ali; Hoffmann, Goesta; Balushi, Noora Al; Gale, Nora; Kodijat, Ardito M.; Fritz, Hermann M.; Atwater, Brian F.
This U.S. Geological Survey (USGS) Open-File report presents a compilation of tsunami modeling studies for the Science Application for Risk Reduction (SAFRR) tsunami scenario. These modeling studies are based on an earthquake source specified by the SAFRR tsunami source working group (Kirby and others, 2013). The modeling studies in this report are organized into three groups. The first group relates to tsunami generation. The effects that source discretization and horizontal displacement have on tsunami initial conditions are examined in section 1 (Whitmore and others). In section 2 (Ryan and others), dynamic earthquake rupture models are explored in modeling tsunami generation. These models calculate slip distribution and vertical displacement of the seafloor as a result of realistic fault friction, physical properties of rocks surrounding the fault, and dynamic stresses resolved on the fault. The second group of papers relates to tsunami propagation and inundation modeling. Section 3 (Thio) presents a modeling study for the entire California coast that includes runup and inundation modeling where there is significant exposure and estimates of maximum velocity and momentum flux at the shoreline. In section 4 (Borrero and others), modeling of tsunami propagation and high-resolution inundation of critical locations in southern California is performed using the National Oceanic and Atmospheric Administration’s (NOAA) Method of Splitting Tsunami (MOST) model and NOAA’s Community Model Interface for Tsunamis (ComMIT) modeling tool. Adjustments to the inundation line owing to fine-scale structures such as levees are described in section 5 (Wilson). The third group of papers relates to modeling of hydrodynamics in ports and harbors. Section 6 (Nicolsky and Suleimani) presents results of the model used at the Alaska Earthquake Information Center for the Ports of Los Angeles and Long Beach, as well as synthetic time series of the modeled tsunami for other selected locales in southern California. Importantly, section 6 provides a comparison of the effect of including horizontal displacements at the source described in section 1 and differences in bottom friction on wave heights and inundation in the Ports of Los Angeles and Long Beach. Modeling described in section 7 (Lynett and Son) uses a higher order physical model to determine variations of currents during the tsunami and complex flow structures such as jets and eddies. Section 7 also uses sediment transport models to estimate scour and deposition of sediment in ports and harbors—a significant effect that was observed in southern California following the 2011 Tohoku tsunami. Together, all of the sections in this report form the basis for damage, impact, and emergency preparedness aspects of the SAFRR tsunami scenario. Three sections of this report independently calculate wave height and inundation results using the source specified by Kirby and others (2013). Refer to figure 29 in section 3, figure 52 in section 4, and figure 62 in section 6. All of these results are relative to a mean high water (MHW) vertical datum. Slight differences in the results are observed in East Basin of the Port of Los Angeles, Alamitos Bay, and the Seal Beach National Wildlife Refuge. However, given that these three modeling efforts involved different implementations of the source, different numerical wave propagation and runup models, and slight differences in the digital elevation models (DEMs), the similarity among the results is remarkable.
SAFRR Tsunami Modeling Working Group
A Tsunami Pilot Study was conducted for the area surrounding the coastal town of Seaside, Oregon, as part of the Federal Emergency Management's (FEMA) Flood Insurance Rate Map Modernization Program (Tsunami Pilot Study Working Group, 2006). The Cascadia subduction zone extends from Cape Mendocino, California, to Vancouver Island, Canada. The Seaside area was chosen because it is typical of many coastal communities subject to tsunamis generated by far- and near-field (Cascadia) earthquakes. Two goals of the pilot study were to develop probabilistic 100-year and 500-year tsunami inundation maps using Probabilistic Tsunami Hazard Analysis (PTHA) and to provide recommendations for improving tsunami hazard assessment guidelines for FEMA and state and local agencies. The study was an interagency effort by the National Oceanic and Atmospheric Administration, U.S. Geological Survey, and FEMA, in collaboration with the University of Southern California, Middle East Technical University, Portland State University, Horning Geoscience, Northwest Hydraulics Consultants, and the Oregon Department of Geological and Mineral Industries. The pilot study model data and results are published separately as a geographic information systems (GIS) data report (Wong and others, 2006). The flood maps and GIS data are briefly described here.
Wong, Florence L.; Venturato, Angie J.; Geist, Eric L.
A feasibility study to develop a tsunami alert system for Mexican earthquakes, using broadband seismograms from the Na-tional Seismological Service, is currently under way. A first step in this direction is a revision of the Mexican tsunami catalogs. In these catalogs, one of the largest tsunamis of this century is reported in the Port of Zihuatanejo and has been related to an earthquake which occurred on November 16, 1925. This earthquake was located at a distance of about 600 km from Zihuat...
Shapiro, N.; Pacheco, J. F.; Singh, S. K.
A methodology of tsunami PSA was developed in this study. A tsunami PSA consists of tsunami hazard analysis, tsunami fragility analysis and system analysis. In the case of tsunami hazard analysis, evaluation of tsunami return period is major task. For the evaluation of tsunami return period, numerical analysis and empirical method can be applied. The application of this method was applied to a nuclear power plant, Ulchin 56 NPP, which is located in the east coast of Korean peninsula. Through this study, whole tsunami PSA working procedure was established and example calculation was performed for one of real nuclear power plant in Korea
The tsunami science and engineering began in Japan, the country the most frequently hit by local and distant tsunamis. The gate to the tsunami science was opened in 1896 by a giant local tsunami of the highest run-up height of 38 m that claimed 22,000 lives. The crucial key was a tide record to conclude that this tsunami was generated by a “tsunami earthquake”. In 1933, the same area was hit again by another giant tsunami. A total system of tsunami disaster mitigation including 10 “hard...
Shuto, Nobuo; Fujima, Koji
An examination of the coastal geomorphology of bays along the Otago coastline, SE New Zealand, has identified a geomorphology consistent with tsunami inundation. A tsunami geomorphology consisting of a number of elements including dune pedestals, hummocky topography, parabolic dune systems, and post-tsunami features resulting from changes to the nearshore sediment budget is discussed. The most prominent features at Blueskin Bay are eroded pedestals although it is speculated that hummocky topo...
Goff, J. R.; Lane, E.; Arnold, J.
Since fault fracturing due to an earthquake can simultaneously cause ground motion and tsunami, it is appropriate to evaluate the ground motion and the tsunami by single fault model. However, several source models are used independently in the ground motion simulation or the tsunami simulation, because of difficulty in evaluating both phenomena simultaneously. Many source models for the 2011 off the Pacific coast of Tohoku Earthquake are proposed from the inversion analyses of seismic observations or from those of tsunami observations. Most of these models show the similar features, which large amount of slip is located at the shallower part of fault area near the Japan Trench. This indicates that the ground motion and the tsunami can be evaluated by the single source model. Therefore, we examine the possibility of the tsunami prediction, using the fault model estimated from seismic observation records. In this study, we try to carry out the tsunami simulation using the displacement field of oceanic crustal movements, which is calculated from the ground motion simulation of the 2011 off the Pacific coast of Tohoku Earthquake. We use two fault models by Yoshida et al. (2011), which are based on both the teleseismic body wave and on the strong ground motion records. Although there is the common feature in those fault models, the amount of slip near the Japan trench is lager in the fault model from the strong ground motion records than in that from the teleseismic body wave. First, the large-scale ground motion simulations applying those fault models used by the voxel type finite element method are performed for the whole eastern Japan. The synthetic waveforms computed from the simulations are generally consistent with the observation records of K-NET (Kinoshita (1998)) and KiK-net stations (Aoi et al. (2000)), deployed by the National Research Institute for Earth Science and Disaster Prevention (NIED). Next, the tsunami simulations are performed by the finite difference calculation based on the shallow water theory. The initial wave height for tsunami generation is estimated from the vertical displacement of ocean bottom due to the crustal movements, which is obtained from the ground motion simulation mentioned above. The results of tsunami simulations are compared with the observations of the GPS wave gauges to evaluate the validity for the tsunami prediction using the fault model based on the seismic observation records.
Akiyama, S.; Kawaji, K.; Fujihara, S.
A promising method of detecting imminent tsunamis and estimating their destructive potential involves the use of Global Positioning System (GPS) data in addition to seismic data. Application of the method is expected to increase the reliability of global tsunami-warning systems, making it possible to save lives while reducing the incidence of false alarms. Tsunamis kill people every year. The 2004 Indian Ocean tsunami killed about 230,000 people. The magnitude of an earthquake is not always a reliable indication of the destructive potential of a tsunami. The 2004 Indian Ocean quake generated a huge tsunami, while the 2005 Nias (Indonesia) quake did not, even though both were initially estimated to be of the similar magnitude. Between 2005 and 2007, five false tsunami alarms were issued worldwide. Such alarms result in negative societal and economic effects. GPS stations can detect ground motions of earthquakes in real time, as frequently as every few seconds. In the present method, the epicenter of an earthquake is located by use of data from seismometers, then data from coastal GPS stations near the epicenter are used to infer sea-floor displacements that precede a tsunami. The displacement data are used in conjunction with local topographical data and an advanced theory to quantify the destructive potential of a tsunami on a new tsunami scale, based on the GPS-derived tsunami energy, much like the Richter Scale used for earthquakes. An important element of the derivation of the advanced theory was recognition that horizontal sea-floor motions contribute much more to generation of tsunamis than previously believed. The method produces a reliable estimate of the destructive potential of a tsunami within minutes typically, well before the tsunami reaches coastal areas. The viability of the method was demonstrated in computational tests in which the method yielded accurate representations of three historical tsunamis for which well-documented ground-motion measurements were available. Development of a global tsunami-warning system utilizing an expanded network of coastal GPS stations was under consideration at the time of reporting the information for this article.
Song, Y. Tony
Full Text Available Tsunami sources are intimately linked to geological events. Earthquakes and landslides are shown to be part of a continuum of complicated geological phenomena. Advances in landslide tsunami research will remain coupled with marine geology research. The landslide tsunami hypothesis is shown to have originated in the scientific literature in the early 1900s. Tsunami science has been slow to embrace the hypothesis in part because of the tremendous uncertainity that it introduces into tsunami gneration. The 1998 Papua New Guyinea event sparked much controbersy regarding the landslide tsunami hypothesis despite a preponderance of the evidence in favor of one simple and consistent explanation of the tsunami source. Part of the difficulty was the unanticipated distinction between slide and slump tsunami sources. Significant controversies still exist over other aspects of the Papua New Guinea event. The landslide hypothesis will become widely acceepted once direct measurements of underwater landslide events are made. These measurements will likely be integrated into a local tsunami warning system.
Michael Mayhew and Michelle Hall, Science Education Solutions Summary The Cascadia Earthquakes and Tsunami Suite contains five case studies organized around understanding the potential for large earthquakes and ...
The tsunami warning system needs further development in Fiji. The MRD earthquake and tsunami plan of action needs to be tested and appropriate authorities drilled in putting this plan into practice. It also needs to be supplemented with an alarm system such that people near the coasts, especially in built-up areas such as Suva can be made aware of impending tsunami danger. The plan of action becomes virtually ineffective when dealing with locally generated tsunamis and for this we have to rely on public education as it is not yet possible or practical to devise a warning system which can be activated within adequate time. 3 refs, 2 figs, 1 tab
Real-time tsunami forecasting is one of the effective ways to mitigate tsunami disasters. Transmission of a tsunami warning based on rapid and accurate tsunami forecasting to coastal communities helps the residents to make the decisions about their evacuation behaviors. Offshore tsunami data take an important role in tsunami forecasting. Tsunamis can be detected at offshore stations earlier than at coastal sites, and the data provide direct information about the impeding tsunamis. When the 2011 Tohoku earthquake occurred, the large tsunamis were clearly observed at various offshore observatories around Japan, such as cabled ocean bottom pressure gauges (OBPGs), GPS buoys and DART. In this study, we retrospectively applied an algorithm of near-field tsunami forecasting (Tsushima et al., 2009, 2012, JGR) to the offshore tsunami data from the 2011 Tohoku earthquake to examine how the algorithm contributes to tsunami forecasting of M9 earthquakes. Our tsunami forecasting algorithm is based on a source estimation. For the algorithm, offshore tsunami waveform data are inverted for spatial distribution of an initial sea-surface displacement, and then coastal tsunami waveforms are synthesized from the estimated source and pre-computed Green's functions by a linear superposition. No assumptions concerning the fault geometry and the size of an earthquake are required in the algorithm. The predictions are repeated by progressively updating the offshore tsunami waveform data. Because individual predictions can be calculated within a few minutes, tsunami predictions can be updated at short intervals of time, thus providing successive tsunami predictions with improved accuracy. We retrospectively applied our algorithm to the tsunami data recorded at 13 offshore stations (6 OBPGs, 6 GPS buoys, and 1 DART) during the 2011 Tohoku tsunami event. As a result of the application made 20 minutes after the earthquake, tsunamis with heights of 5-10 m were forecasted at the coastal sites near the source area (northern Tohoku) where the sea-level increase due to the actual tsunami began to exceed 1 m after an elapsed time of 25-30 minutes. These good predictions were owing to the observation at the near-field stations, especially OBPGs. Many offshore stations are located between these coastal sites and the source area with enough azimuthal coverage to constrain the estimated source strongly. Retrospective tsunami forecast made 30 minutes after the earthquake shows that predicted tsunami waveforms agree with the observations at the coastal sites to the north of the source (Hokkaido) where the actual tsunami arrives 50 minutes after the earthquake. These results suggest a possibility that our forecasting method could have contributed to the issuing of reliable near-field tsunami warning for M9 earthquakes. On the other hand, the predictions do not match the observations at the coasts to the south of the source (southern Tohoku to Kanto). This may be because the coverage of offshore stations is relatively poor there. Addition of offshore stations is one of the solutions of the problem. We also present a method of tsunami forecasting based on joint use of offshore tsunami and onshore GPS data and its application to the 2011 Tohoku earthquake. The method is effective to improve tsunami predictions in the earlier period after an earthquake.
Tsushima, H.; Hayashi, Y.; Hirata, K.; Baba, T.; Ohta, Y.; Iinuma, T.; Hino, R.; Tanioka, Y.; Sakai, S.; Shinohara, M.; Kanazawa, T.; Maeda, K.
Tsunami detection instruments were installed along remote shoreline campgrounds of Hawaii Volcanoes National Park in August of 2009. Components include water sensing devices at elevations of about 10 feet above sea level located at distances of about 200 feet from the shoreline and satellite communicators located further inland at higher elevations that will send daily status reports and flood alerts from the water sensors as they occur to the Pacific Tsunami Warning Center in Honolulu. Such ...
Walker, Daniel A.
A series of visualizations of the tsunami generated by the 1906 earthquake. Included are maps of the San Andreas fault offshore, in San Francisco Bay, diagrams of the magnitude of the slip under the San Francisco Bay, and animations of wave height following the earthqake. Two separate animations are featured as QuickTime movies; one is centered on the Golden Gate Bridge, the other shows the whole San Francisco Bay.
Usgs, Tsunami A.
Full Text Available A report to the UN’s Economic and Social Council (ECOSOC identifies lessons learned from the humanitarian response. Recommendations stress the need for national ownership and leadership of disaster response and recovery, improved coordination, transparent use of resources, civil society engagement and greater emphasis on risk reduction.
A report to the UN’s Economic and Social Council (ECOSOC) identifies lessons learned from the humanitarian response. Recommendations stress the need for national ownership and leadership of disaster response and recovery, improved coordination, transparent use of resources, civil society engagement and greater emphasis on risk reduction.
Marion Couldrey; Tim Morris
The well-balanced, positivity-preserving scheme of Audusse et al. (SIAM J Sci Comput 25(6):2050-2065, 2004), for the solution of the Saint-Venant equations with wetting and drying, is generalised to an adaptive quadtree spatial discretisation. The scheme is validated using an analytical solution for the oscillation of a fluid in a parabolic container, as well as the classic Monai tsunami laboratory benchmark. An efficient database system able to dynamically reconstruct a multiscale bathymetry based on extremely large datasets is also described. This combination of methods is successfully applied to the adaptive modelling of the 2004 Indian ocean tsunami. Adaptivity is shown to significantly decrease the exponent of the power law describing computational cost as a function of spatial resolution. The new exponent is directly related to the fractal dimension of the geometrical structures characterising tsunami propagation. The implementation of the method as well as the data and scripts necessary to reproduce the results presented are freely available as part of the open-source Gerris Flow Solver framework.
Full Text Available Reinforced concrete (RC buildings with openings in the masonry infill panels have shown superior performance to those without openings in the devastating 2004 Indian Ocean Tsunami. Understanding the effect of openings and the resulting tsunami force is essential for an economical and safe design of vertical evacuation shelters against tsunamis. One-to-one hundred scale building models with square shape in plan were tested in a 40 m long hydraulic flume with 1 m x 1 m cross section. A mild slope of 0.5 degree representing the beach condition at Phuket, Thailand was simulated in the hydraulic laboratory. The model dimensions were 150 mm x 150 mm x 150 mm. Two opening configurations of the front and back walls were investigated, viz., 25% and 50% openings. Pressure sensors were placed on the faces of the model to measure the pressure distribution. A high frequency load cell was mounted at the base of the model to record the tsunami forces. A bi-linear pressure profile is proposed for determining the maximum tsunami force acting on solid square buildings. The influence of openings on the peak pressures on the front face of the model is found to be practically insignificant. For 25% and 50% opening models, the tsunami forces reduce by about 15% and 30% from the model without openings, respectively. The reduction in the tsunami force clearly demonstrates the benefit of openings in reducing the effect of tsunami on such buildings.
Tsunamis sind Naturereignisse, die zu den verheerendsten weltweiten Katastrophen gehören, obwohl sie relativ selten auftreten. Da Tsunamis in letzter Zeit zahlreiche Opfer und schwere Zerstörungen in grossen Küstenregionen verursacht haben, sind sie Ziel intensivierter Forschungen geworden. Die Grundlage zur Reduzierung von Tsunamiopfern ist ein kontinuierliches Monitoring der Seismizität. Da eine Erdbebenvorhersage nicht möglich ist, sind Tsunamifrühwarnungen das primäre Ziel der Fors...
Full Text Available We present prima facie evidence that upon the onset of the Tohoku tsunami of Mar. 11, 2011 infrared radiation was emitted by the tsunami and was detected by the Japanese satellite MTSAT-IR1, in agreement with our earlier findings for the Great Sumatra Tsunami of 2004. Implications for a worldwide Tsunami Early Warning System are discussed.
Frank C. Lin
Disaster recovery after the Indian Ocean tsunami in 2004 led to a number of challenges and raised issues concerning land rights and housing reconstruction in the affected countries. This paper discusses the resistance to relocation of fishing communities in Chennai, India. Qualitative research methods were used to describe complexities in the debate between the state and the community regarding relocation, and the paper draws attention to the dimensions of the state–community interface in t...
Historical and geological records both indicate tsunami inundation of New Zealand in the 700 years since the first human settlement. In addition, Maori oral traditions refer to unusual waves that might have been tsunami waves, although the accounts are open to other interpretations. Tsunami evidence has rarely been proposed from archaeological sites, primarily because of a limited understanding of the requisite evidence and environmental context. We list a criteria suggesting possible tsunami inundation of archaeological sites based upon geoarchaeological data, and use them in a case study from the Archaic Maori occupation site at Wairau Bar. The list is possibly incomplete, but indicates that archaeological investigations can gain from assessments of changing environmental conditions through time at any individual site. Our intention is not to prove tsunami inundation; rather, it is to point to archaeological sites as possible sources of information. We highlight the potential of the Wairau Bar site for further investigation.
McFadgen, B. G.; Goff, J. R.
Fukushima Daiichi and Daini Nuclear Power Stations (NPSs) were struck by the earthquake off the pacific coast in the Tohoku District, which occurred at 14:46 on March 11, 2011. Afterwards, tsunamis struck the Tohoku District. In terms of the earthquake observed at the Fukushima NPSs, the acceleration response spectra of the earthquake movement observed on the basic board of reactor buildings exceeded the acceleration response spectra of the response acceleration to the standard seismic ground motion Ss for partial periodic bands at the Fukushima Daiichi NPS. As for the Fukushima Daini NPS, the acceleration response spectra of the earthquake movement observed on the basic board of the reactor buildings was below the acceleration response spectra of the response acceleration to the standard seismic ground motion Ss. Areas inundated by Tsunami at each NPS were investigated and tsunami inversion analysis was made to build tsunami source model to reproduce tide record, tsunami height, crustal movement and inundated area, based on tsunami observation records in the wide areas from Hokkaido to Chiba prefectures. Tsunami heights of Fukushima Daiichi and Daini NPSs were recalculated as O.P. +13m and +9m respectively and tsunami peak height difference was attributed to the extent of superposition of tsunami waves of tsunami earthquake type of wave source in the area along interplane trench off the coast in the Fukushima prefecture and interplane earthquake type of wave source interplane earthquake type of wave source in rather deep interplate area off the coast in the Miyagi prefecture. (T. Tanaka)
Tsunami warning in near-field conditions is a critical issue in the Mediterranean Sea since the most important tsunami sources are situated within tsunami wave travel times starting from about five minutes. The project NEARTOWARN (2012-2013) supported by the EU-DG ECHO contributed substantially to the development of new tools for the near-field tsunami early warning in the Mediterranean. One of the main achievements is the development of a local warning system in the test-site of Rhodes island (Rhodes Early Warning System for Earthquakes and Tsunamis - REWSET). The system is composed by three main subsystems: (1) a network of eight seismic early warning devices installed in four different localities of the island, one in the civil protection, another in the Fire Brigade and another two in municipality buildings; (2) two radar-type (ultrasonic) tide-gauges installed in the eastern coastal zine of the island which was selected since research on the historical earthquake and tsunami activity has indicated that the most important, near-field tsunami sources are situated offshore to the east of Rhodes; (3) a crisis Geographic Management System (GMS), which is a web-based and GIS-based application incorporating a variety of thematic maps and other information types. The seismic early warning devices activate by strong (magnitude around 6 or more) earthquakes occurring at distances up to about 100 km from Rhodes, thus providing immediate mobilization of the civil protection. The tide-gauges transmit sea level data, while during the crisis the GMS supports decisions to be made by civil protection. In the near future it is planned the REWSET system to be integrated with national and international systems. REWSET is a prototype which certainly could be developed in other coastal areas of the Mediterranean and beyond.
Papadopoulos, Gerasimos; Argyris, Ilias; Aggelou, Savvas; Karastathis, Vasilis
[EN] Tsunamis are usually associated with submarine tectonic activity. Tsunamis transform the shore owing to their erosive and sedimentary capacity. Evidence of tsunamis can be preserved in the geological record for millions of years. The tsunami sedimentary record is a useful tool for obtaining paleoseismic information since it is the only record available that allows us to detect and to analyze ancient offshore seismicity. Three examples of tsunami deposits which contribute to the ...
Goy, Jose? Luis; Luque Ripoll, L.; Zazo, Caridad; Dabrio, Cristino J.; Gabriel Silva, Pablo; Lario, J.
This review summarizes the concepts of seismogenic tsunami waves. Principles of short-term tsunami forecasting and tsunami recording systems are discussed. The traditional approach to describing tsunami generation by earthquakes is outlined and its drawbacks are analyzed. The main and secondary effects are distinguished which are responsible for the formation of waves by underwater earthquakes. The existing numerical codes of tsunami dynamics are described.
Nosov, M. A.
The importance of tsunami hazard assessment has increased in recent years as a result of catastrophic consequences from events such as the 2004 Indian Ocean and 2011 Japan tsunamis. In particular, probabilistic tsunami hazard assessment (PTHA) methods have been emphasized to include all possible ways a tsunami could be generated. Owing to the scarcity of tsunami observations, a computational approach is used to define the hazard. This approach includes all relevant sources that may cause a ts...
Geist, Eric L.; Lynett, Patrick J.
The highly vulnerable Pacific southwest coast of Mexico has been repeatedly affected by local, regional and remote source tsunamis. Mexico presently has no national tsunami warning system in operation. The implementation of key elements of a National Program on Tsunami Detection, Monitoring, Warning and Mitigation is in progress. For local and regional events detection and monitoring, a prototype of a robust and low cost high frequency sea-level tsunami gauge, sampling every minute and equipped with 24 hours real time transmission to the Internet, was developed and is currently in operation. Statistics allow identification of low, medium and extreme hazard categories of arriving tsunamis. These categories are used as prototypes for computer simulations of coastal flooding. A finite-difference numerical model with linear wave theory for the deep ocean propagation, and shallow water nonlinear one for the near shore and interaction with the coast, and non-fixed boundaries for flooding and recession at the coast, is used. For prevention purposes, tsunami inundation maps for several coastal communities, are being produced in this way. The case of the heavily industrialized port of Lázaro Cárdenas, located on the sand shoals of a river delta, is illustrated; including a detailed vulnerability assessment study. For public education on preparedness and awareness, printed material for children and adults has been developed and published. It is intended to extend future coverage of this program to the Mexican Caribbean and Gulf of Mexico coastal areas.
Farreras, Salvador; Ortiz, Modesto; Gonzalez, Juan I.
Geological and historical records of the coast of British Columbia (BC) and orally transmitted legends from the First Nations in the area indicate the recurrence of tsunamis in this region. Recent studies show a 40% to 80% probability of a local earthquake occurring in the next 50 years over the Cascadia subduction zone, generating a tsunami run-up higher than 1.5 meters. Ocean Networks Canada (ONC) operates ocean observatories off the west coast of BC. Smart Oceans BC is a new multifaceted program to support coastal communities and decision makers by leveraging the unique capabilities of ONC's advanced cabled ocean observatories to inform public safety, marine safety, and environmental monitoring.
Insua, Tania Lado; Moran, Kate
The Second Workshop on the Technical Aspects of Tsunami Warning Systems, Tsunami Analysis, Preparedness, Observation, and Instrumentation, sponsored and convened by the Intergovernmental Oceanographic Commission (IOC), was held on 1-2 August 1989, in the modern and attractive research town of Academgorodok, which is located 20 km south from downtown Novosibirsk, the capital of Siberia, USSR. The Program was arranged in eight major areas of interest covering the following: Opening and Introduction; Survey of Existing Tsunami Warning Centers - present status, results of work, plans for future development; Survey of some existing seismic data processing systems and future projects; Methods for fast evaluation of Tsunami potential and perspectives of their implementation; Tsunami data bases; Tsunami instrumentation and observations; Tsunami preparedness; and finally, a general discussion and adoption of recommendations. The Workshop presentations not only addressed the conceptual improvements that have been made, but focused on the inner workings of the Tsunami Warning System, as well, including computer applications, on-line processing and numerical modelling. Furthermore, presentations reported on progress has been made in the last few years on data telemetry, instrumentation and communications. Emphasis was placed on new concepts and their application into operational techniques that can result in improvements in data collection, rapid processing of the data, in analysis and prediction. A Summary Report on the Second International Tsunami Workshop, containing abstracted and annotated proceedings has been published as a separate report. The present Report is a Supplement to the Summary Report and contains the full text of the papers presented at this Workshop. Refs, figs and tabs
The management of natural crises is an important application field of the technology developed in the project Collaborative, Complex, and Critical Decision-Support in Evolving Crises (TRIDEC), co-funded by the European Commission in its Seventh Framework Programme. TRIDEC is based on the development of the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS) providing a service platform for both sensor integration and warning dissemination. In TRIDEC new developments in Information and Communication Technology (ICT) are used to extend the existing platform realising a component-based technology framework for building distributed tsunami warning systems for deployment, e.g. in the North-eastern Atlantic, the Mediterranean and Connected Seas (NEAM) region. The TRIDEC system will be implemented in three phases, each with a demonstrator. Successively, the demonstrators are addressing challenges, such as the design and implementation of a robust and scalable service infrastructure supporting the integration and utilisation of existing resources with accelerated generation of large volumes of data. These include sensor systems, geo-information repositories, simulation tools and data fusion tools. In addition to conventional sensors also unconventional sensors and sensor networks play an important role in TRIDEC. The system version presented is based on service-oriented architecture (SOA) concepts and on relevant standards of the Open Geospatial Consortium (OGC), the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS). In this way the system continuously gathers, processes and displays events and data coming from open sensor platforms to enable operators to quickly decide whether an early warning is necessary and to send personalized warning messages to the authorities and the population at large through a wide range of communication channels. The system integrates OGC Sensor Web Enablement (SWE) compliant sensor systems for the rapid detection of hazardous events, like earthquakes, sea level anomalies, ocean floor occurrences, and ground displacements. Using OGC Web Map Service (WMS) and Web Feature Service (WFS) spatial data are utilized to depict the situation picture. The integration of a simulation system to identify affected areas is considered using the OGC Web Processing Service (WPS). Warning messages are compiled and transmitted in the OASIS Common Alerting Protocol (CAP) together with addressing information defined via the OASIS Emergency Data Exchange Language - Distribution Element (EDXL-DE). The first system demonstrator has been designed and implemented to support plausible scenarios demonstrating the treatment of simulated tsunami threats with an essential subset of a National Tsunami Warning Centre (NTWC). The feasibility and the potentials of the implemented approach are demonstrated covering standard operations as well as tsunami detection and alerting functions. The demonstrator presented addresses information management and decision-support processes in a hypothetical natural crisis situation caused by a tsunami in the Eastern Mediterranean. Developments of the system are based to the largest extent on free and open source software (FOSS) components and industry standards. Emphasis has been and will be made on leveraging open source technologies that support mature system architecture models wherever appropriate. All open source software produced is foreseen to be published on a publicly available software repository thus allowing others to reuse results achieved and enabling further development and collaboration with a wide community including scientists, developers, users and stakeholders. This live demonstration is linked with the talk "TRIDEC Natural Crisis Management Demonstrator for Tsunamis" (EGU2012-7275) given in the session "Architecture of Future Tsunami Warning Systems" (NH5.7/ESSI1.7).
Hammitzsch, M.; Reißland, S.; Lendholt, M.
Full Text Available In this work we present the result of a study aimed at examining the Italian earthquake sequences that occurred in the area of the central Adriatic sea with the purpose of understanding whether some of them were accompanied by tsunami effects. The motivation for this research was the update and enrichment of the Italian Tsunami Catalogue. The result was that evidence was found for two new cases of earthquake-induced tsunamis: these are the August 1916 Rimini and the October 1930 Ancona events. The bulk of the present research consisted in collecting all the available data on the earthquakes that affected the selected area in the past century and in identifying those potentially capable of generating tsunamis. During the study all the available material was gathered, which includes specific monographs and scientific papers, articles available in contemporary chronicles and in local and national newspapers. The final result of this research will improve our knowledge of the tsunamigenic activity of the central Adriatic sea and contribute to the assessment of the tsunami hazard and risk along these coasts, that especially in the peak season form one of the most densely populated areas of the Italian peninsula with flat and large beaches and water front resorts crowded of tourists.
Results are presented regarding the first commercially available, fully operational, tsunami detection system to have passed stringent U.S. government testing requirements and to have successfully demonstrated its ability to detect an actual tsunami at sea. Spurred by the devastation of the December 26, 2004, Indian Ocean tsunami that killed more than 230,000 people, the private sector actively supported the Intergovernmental Oceanographic Commission's (IOC"s) efforts to develop a tsunami warning system and mitigation plan for the Indian Ocean region. As each country in the region developed its requirements, SAIC recognized that many of these underdeveloped countries would need significant technical assistance to fully execute their plans. With the original focus on data fusion, consequence assessment tools, and warning center architecture, it was quickly realized that the cornerstone of any tsunami warning system would be reliable tsunami detection buoys that could meet very stringent operational standards. Our goal was to leverage extensive experience in underwater surveillance and oceanographic sensing to produce an enhanced and reliable deep water sensor that could meet emerging international requirements. Like the NOAA Deep-ocean Assessment and Recording of Tsunamis (DART TM ) buoy, the SAIC Tsunami Buoy (STB) system consists of three subsystems: a surfaccommunications buoy subsystem, a bottom pressure recorder subsystem, and a buoy mooring subsystem. With the operational success that DART has demonstrated, SAIC decided to build and test to the same high standards. The tsunami detection buoy system measures small changes in the depth of the deep ocean caused by tsunami waves as they propagate past the sensor. This is accomplished by using an extremely sensitive bottom pressure sensor/recorder to measure very small changes in pressure as the waves move past the buoy system. The bottom pressure recorder component includes a processor with algorithms that recognize these characteristics, and then immediately alerts a tsunami warning center through the communications buoy when the processor senses one of these waves. In addition to the tsunami detection buoy system, an end-to-end tsunami warning system was developed that builds upon the country's existing disaster warning infrastructure. This warning system includes 1) components that receive, process, and analyze buoy, seismic and tide gauge data; 2) predictive tools and a consequence assessment tool set to provide decision support; 3) operation center design and implementation; and 4) tsunami buoy operations and maintenance support. The first buoy was deployed Oct. 25, 2006, approximately 200 nautical miles west of San Diego in 3,800 meters of water. Just three weeks later, it was put to the test during an actual tsunami event. On Nov. 15, 2006, an 8.3 magnitude earthquake rocked the Kuril Islands, located between Japan and the Kamchatka Peninsula of Russia. That quake generated a small tsunami. Waves from the tsunami propagated approximately 4,000 nautical miles across the Pacific Ocean in about nine hours-- a speed of about 445 nautical miles per hour when this commercial buoy first detected them. Throughout that event, the tsunami buoy system showed excellent correlation with data collected by a NOAA DART buoy located 28 nautical miles north of it. Subsequent analysis revealed that the STB matched DART operational capabilities and performed flawlessly. The buoy proved its capabilities again on Jan. 13, 2007, when an 8.1 magnitude earthquake occurred in the same region, and the STB detected the seismic event. As a result of the successes of this entire project, SAIC recently applied for and received a license from NOAA to build DART systems.
Lawson, R. A.
Deep ocean tsunami measurements are needed to provide open ocean boundary conditions for testing numerical models in hindcast studies, and for improving our understanding of tsunami generation and propagation. Jacob (1984) has identified a portion of the Aleutian Trench which includes the Shumagin Island group as a seismic gap (the Shumagin Gap); he has computed estimates which indicate that the probability of a great earthquake occurrence (Mw > 7.8) is significantly higher for this region than any other in the U.S. Because tsunamigenic earthquakes along a major portion of the seismically active Aleutian trench threaten Hawaii and the U.S. west coast, and because a large tsunami is possible in the event of a great earthquake in the Shumagin Gap, this region has become the focus of a long-term monitoring program by the Pacific Marine Environmental Laboratory (PMEL) of the National Oceanic and Atmospheric Administration (NOAA). (author). 22 refs, 1 fig
Considering its huge magnitude and its location in a densely populated area of Chile, the Maule seism of 27 February 2010 generated a low amount of victims. However, post-seismic tsunamis were particularly devastating on that day; surprisingly, no full alert was launched, not at the national, regional or local level. This earthquake and associated tsunamis are of interest in the context of natural hazards management as well as crisis management planning. Instead of focusing exclusively on the event itself, this article places emphasis on the process, systems and long-term approach that led the tsunami alert mechanism to be ineffectual. Notably, this perspective reveals interrelated forerunner signs of vulnerability. PMID:24601922
Exact arrival time of tsunami wave at coast or/and sensor is among important parameters for tsunami risk mitigation. Among the existing methods we mention: simulation of synthetic tsunami wave propagation from the given source; permanent data check at sensor system. Both approaches require extended CPU time or data transfer. Here we suggest alternative method based only on kinematics computation. The method is based on kinematic calculation of tsunami wave front line. Precise algorithms to move the points at the front line and, in case of necessity, to add new points, have been proposed. To start with, this method was successfully tested in an area with constant depth. Then the model bathymetry with parabolic and sloping bottom relief, in which cases exact analytical solutions are available, were studied. New algorithm was proved to be precise. The method gives possibility to compute not only tsunami travel times but also the wave rays. Tsunami amplitude can be estimated by wave-ray's divergence and depth change along wave route. The wave amplitude was estimated and then compared to results of numerical tests, obtained within the shallow-water numerical modeling of tsunami propagation using the MOST software package. For the model (slope-like) bathymetry the results differs by only a few percent. The advantage of proposed method is rapidness and low computer resources requirement.
Lavrentyev, Mikhail; Romanenko, Alexey; Marchuk, Andery; Vassilyev, George
Full Text Available An examination of the coastal geomorphology of bays along the Otago coastline, SE New Zealand, has identified a geomorphology consistent with tsunami inundation. A tsunami geomorphology consisting of a number of elements including dune pedestals, hummocky topography, parabolic dune systems, and post-tsunami features resulting from changes to the nearshore sediment budget is discussed. The most prominent features at Blueskin Bay are eroded pedestals although it is speculated that hummocky topography may be present in the bay. Tsunami geomorphology at Long Beach is more comprehensive with a marked association between pedestals and a hummocky topography. A full suite of potential geomorphological features however, is not present at either site. The type of features formed by a tsunami, and the ability to detect and interpret a tsunami geomorphology, hinges on the interaction between five key variables; sand availability, embayment type, nature of the coast, accumulation space, and landward environmental conditions. An appreciation of the geomorphic setting and history of a coast is therefore of fundamental importance when identifying what to look for and where to look for tsunami evidence. It is also important to realise that these features can also be formed by other processes.
J. R. Goff
The ages of some tsunami deposits can be determined by optical dating, a key requirement being that the deposits are derived from sediment that was reworked and exposed to daylight by tidal currents, waves, wind, or bioturbation during the last years before the tsunami. Measurements have been made using 1.4 eV (infrared) excitation of K-feldspar grains separated from samples of prehistoric tsunami sand sheets and modern analogs of tsunami source sediments at four sites in Washington state and British Columbia. Source sands gave equivalent doses indicative of recent exposure to daylight. Tsunami sand at Cultus Bay, Washington, yielded an optical age of 1285 ± 95 yr (calendric years before A.D. 1995, ±1?). At 2?, this age overlaps the range of from 1030 to 1100 yr determined through a combination of high-precision radiocarbon dating and stratigraphic correlation. Tsunami sands at three sites near Tofino and Port Alberni on Vancouver Island, British Columbia, have optical ages of 260 ± 20, 325 ± 25, and 335 ± 45 yr. Historical records and radiocarbon dating show that the sand at each of the three sites is between 150 and 400 yr old. These optical ages support the hypothesis that the Vancouver Island sands were deposited by a tsunami generated by a large earthquake on the Cascadia subduction zone about 300 yr ago.
Huntley, David J.; Clague, John J.
The Geophysical Laboratory, which is also the French Polynesia Tsunami Warning Center (Centre Polynesien de Prevention des Tsunamis - CPPT) disposes of the data recorded by the Polynesian Seismic Network which includes 21 short-period stations, 4 broad-band three component long period stations and 2 tide gauge stations. These stations are, for the most, telemetred toward the CPPT in Tahiti which is equipped with data processing means. The data acquisition is performed on optic discs, tape drive recordings and graphic recordings. In the CPPT, the Tsunami Warning is based on the measurements of the Seismic Moment through the mantle magnitude Mm and the proportionality of observed tsunami height to this seismic moment. The new mantle magnitude scale, Mm used the measurement of the mantle Rayleigh and Love wave energy in the 50-300 s. period range and is directly related to the seismic moment through Mm = log Mo - 20. The knowledge of the seismic moment allows computation of an estimate of the high-seas amplitude of a range of expectable tsunami heights. In establishing seismic thresholds for tsunami warning, we assume that tsunami risk is substantial when the upper level found on the amplitude predicted at PPT reach 1 m. On this basis, the risk levels have been identified as a function of the magnitude Mm. For the Polynesian Islands the destructive tsunami danger would subsequently exist for Mm ? 8.7 (Mo ? 5 x 1028 dyn-cm), in the case of epicenters in Sam-cm), in the case of epicenters in Samoa, Tonga, Kermadec and Mm ? 9.0 (Mo ? 1029 dyn-cm) for other epicenters. This procedure is fully automatic: One computer detects, locates and estimates the seismic moment through the Mm magnitude and, in terms of moment, gives an amplitude window of the expected tsunami. These different operations are executed in real time. In addition, the operator can use the historic references and, if necessary, the acoustic T waves. 13 refs, 11 figs
A pilot project was initiated in 2009 in Humboldt Bay, about 370 kilometers (km) north of San Francisco, California, to measure the currents produced by tsunamis. Northern California is susceptible to both near- and far-field tsunamis and has a historic record of damaging events. Crescent City Harbor, located approximately 100 km north of Humboldt Bay, suffered US 20 million in damages from strong currents produced by the 2006 Kuril Islands tsunami and an additional US 20 million from the 2011 Japan tsunami. In order to better evaluate these currents in northern California, we deployed a Nortek Aquadopp 600kHz 2D Acoustic Doppler Current Profiler (ADCP) with a one-minute sampling interval in Humboldt Bay, near the existing National Oceanic and Atmospheric Administration (NOAA) National Ocean Service (NOS) tide gauge station. The instrument recorded the tsunamis produced by the Mw 8.8 Chile earthquake on February 27, 2010 and the Mw 9.0 Japan earthquake on March 11, 2011. Currents from the 2010 tsunami persisted in Humboldt Bay for at least 30 hours with peak amplitudes of about 0.3 meters per second (m/s). The 2011 tsunami signal lasted for over 86 hours with peak amplitude of 0.95 m/s. Strongest currents corresponded to the maximum change in water level as recorded on the NOAA NOS tide gauge, and occurred 90 minutes after the initial wave arrival. No damage was observed in Humboldt Bay for either event. In Crescent City, currents for the first three and a half hours of the 2011 Japan tsunami were estimated using security camera video footage from the Harbor Master building across from the entrance to the small boat basin, approximately 70 meters away from the NOAA NOS tide gauge station. The largest amplitude tide gauge water-level oscillations and most of the damage occurred within this time window. The currents reached a velocity of approximately 4.5 m/s and six cycles exceeded 3 m/s during this period. Measured current velocities both in Humboldt Bay and in Crescent City were compared to calculated velocities from the Method of Splitting Tsunamis (MOST) numerical model. For Humboldt Bay, the 2010 model tsunami frequencies matched the actual values for the first two hours after the initial arrival however the amplitudes were underestimated by approximately 65%. MOST replicated the first four hours of the 2011 tsunami signal in Humboldt Bay quite well although the peak flood currents were underestimated by about 50%. MOST predicted attenuation of the signal after four hours but the actual signal persisted at a nearly constant level for more than 48 hours. In Crescent City, the model prediction of the 2011 frequency agreed quite well with the observed signal for the first two and a half hours after the initial arrival with a 50% underestimation of the peak amplitude. The results from this project demonstrate that ADCPs can effectively record tsunami currents for small to moderate events and can be used to calibrate and validate models (i.e. MOST) in order to better predict hazardous tsunami conditions and improve planned responses to protect lives and property, especially within harbors. An ADCP will be installed in Crescent City Harbor and four additional ADCPs are being deployed in Humboldt Bay during the fall of 2012.
Admire, A. R.; Dengler, L.; Crawford, G. B.; uslu, B. U.; Montoya, J.
This monographic explain what it happened last December on Indonesia, the origin of the tsunamis, the effects on the coast, tsunami warning system, etc. To finish we want to emphasize the importance that has the knowledge of this phenomenon and the knowledge of the tsunami and earthquake safety rules. This article presents how explain risks in the classroom with examples about myths, legends, survivors’ chronicles, literature etc
Brusi I Belmonte, David; Gonza?lez, Marta; Figueras, Sara
he catalogs available in the literature show that tsunamis affecting Italian coasts are not very strong, except for a few well analyzed events, i.e. the Messina December 28, 1908 tsunami. This study aims at making a careful revision of some minor tsunamigenic events, in particular those occurred along the coasts of the Central Tyrrhenian Sea, considering tsunamis associated with earthquakes, from 1700 to 1919. These events have been poorly studied so far, and need a check to verify their reli...
Tertulliani, A.; Maramai, A.
The Method of Splitting Tsunamis (MOST) model adapted by National Oceanic and Atmospheric Administration (NOAA) for tsunami forecasting operations is praised for its computational efficiency, associated with the use of splitting technique. It will be shown, however, that splitting the computations between and directions results in specific sensitivity to the treatment of land-water boundary. Slight modification to the reflective boundary condition in MOST caused an appreciable difference in the results. This is demonstrated with simulations of the Tohoku-2011 tsunami from the source earthquake to Monterey Bay, California, and in southeast Alaska, followed by comparison with tide gage records. In the first case, the better representation of later waves (reflected from the coasts) by the modified model in a Pacific-wide simulation resulted in twice as long match between simulated and observed tsunami time histories at Monterey gage. In the second case, the modified model was able to propagate the tsunami wave and approach gage records at locations within narrow channels (Juneau, Ketchikan), to where MOST had difficulty propagating the wave. The modification was extended to include inundation computation. The resulting inundation algorithm (Cliffs) has been tested with the complete set of NOAA-recommended benchmark problems focused on inundation. The solutions are compared to the MOST solutions obtained with the version of the MOST model benchmarked for the National Tsunami Hazard Mitigation Program in 2011. In two tests, Cliffs and MOST results are very close, and in another two tests, the results are somewhat different. Very different regimes of generation/disposal of water by Cliffs and MOST inundation algorithms, which supposedly affected the benchmarking results, have been discussed.
We investigate inflation driven by the evolution of highly excited quantum states within the framework of out of equilibrium field dynamics. These states are characterized by a non-perturbatively large number of quanta in a band of momenta but with vanishing expectation value of the scalar field. They represent the situation in which initially a non-perturbatively large energy density is localized in a band of high energy quantum modes and are coined tsunami-waves. The self-consistent evolution of this quantum state and the scale factor is studied analytically and numerically. It is shown that the time evolution of these quantum states lead to two consecutive stages of inflation under conditions that are the quantum analogue of slow-roll. The evolution of the scale factor during the first stage has new features that are characteristic of the quantum state. During this initial stage the quantum fluctuations in the highly excited band build up an effective homogeneous condensate with a non-perturbatively large amplitude as a consequence of the large number of quanta. The second stage of inflation is similar to the usual classical chaotic scenario but driven by this effective condensate. The excited quantum modes are already superhorizon in the first stage and do not affect the power spectrum of scalar perturbations. Thus, this tsunami quantum state provides a field theoretical justification for chaotic scenarios driven by a classical homogeneous scalar field of large amsical homogeneous scalar field of large amplitude
The generation and propagation of the November 1, 1755 Lisbon earthquake generated tsunami is of current interest to the IOCARIBE Tsunami Scientific Steering Committee.The November 1, 1755 Lisbon earthquake generated a tsunami with a period of one hour and amplitudes of 20 meters at Lisbon and along the African and south European coasts, of 4 meters along the English coast, and of 7 meters at Saba in the Caribbean after 7 hours of travel. The modeling was performed using the SWAN code whi...
Mader, Charles L.
Full Text Available The 1946 Aleutian earthquake was a typical tsunami earthquake which generated abnormally larger tsunami than expected from its seismic waves. Previously, Johnson and Satake (1997 estimated the fault model of this earthquake using the tsunami waveforms observed at tide gauges. However, they did not model the second pulse of the tsunami at Honolulu although that was much larger than the first pulse. In this paper, we numerically computed the tsunami waveforms using the linear Boussinesq equation to determine the fault model which explains the observed tsunami waveforms including the large second pulse observed at Honolulu. The estimated fault width is 40–60 km which is much narrower than the fault widths of the typical great underthrust earthquakes, the 1957 Aleutian and the 1964 Alasuka earthquakes. A previous study of the 1896 Sanriku earthquake, another typical tsunami earthquake, suggested that the additional uplift of the sediments near the Japan Trench had a large effect on the tsunami generation. In this study, we also show that the additional uplift of the sediments near the trench, due to a large coseismic horizon-tal movement of the backstop, had a significant effect on the tsunami generation of the 1946 Aleutian earthquake. The estimated seismic moment of the 1946 Aleutian earthquake is 17–19 × 1020 20 Nm (Mw 8.1.
The tsunami in the East Sea occurred after powerful earthquake July 12, 1993 is analyzed. Data of the measured runup heights along the eastern coast of the East Sea are processed. It is shown the log-normal function is best fit for the distribution of the wave heights. Numerical simulations of tsunami propagation in the East Sea is performed and computed, results are compared with observed data. Prognostic characteristics of potential tsunamis in the East Sea are discussed. Zones of potential danger tsunami sources are selected
We evaluate here the tsunami hazard in the northwestern Indian Ocean. The maximum regional earthquake calculated from seismic hazard analysis, was used as the characteristic earthquake for our tsunami hazard assessment. This earthquake, with a moment magnitude of M w 8.3 and a return period of about 1000 years, was moved along the Makran subduction zone (MSZ) and its possible tsunami wave height along various coasts was calculated via numerical simulation. Both seismic hazard analysis and numerical modeling of the tsunami were validated using historical observations of the Makran earthquake and tsunami of the 1945. Results showed that the possible tsunami may reach a maximum height of 9.6 m in the region. The distribution of tsunami wave height along various coasts is presented. We recommend the development of a tsunami warning system in the region, and emphasize the value of education as a measure to mitigate the death toll of a possible tsunami in this region.
Heidarzadeh, Mohammad; Pirooz, Moharram D.; Zaker, Nasser H.; Synolakis, Costas E.
It is meaningful for tsunami assessment to evaluate phenomena beyond the design basis as well as seismic design. Because once we set the design basis tsunami height, we still have possibilities tsunami height may exceeds the determined design tsunami height due to uncertainties regarding the tsunami phenomena. Probabilistic tsunami risk assessment consists of estimating for tsunami hazard and fragility of structures and executing system analysis. In this report, we apply a method for probabilistic tsunami hazard analysis (PTHA). We introduce a logic tree approach to estimate tsunami hazard curves (relationships between tsunami height and probability of excess) and present an example for Japan. Examples of tsunami hazard curves are illustrated, and uncertainty in the tsunami hazard is displayed by 5-, 16-, 50-, 84- and 95-percentile and mean hazard curves. The result of PTHA will be used for quantitative assessment of the tsunami risk for important facilities located on coastal area. Tsunami hazard curves are the reasonable input data for structures and system analysis. However the evaluation method for estimating fragility of structures and the procedure of system analysis is now being developed. (authors)
The Seychelles, an archipelago in the Indian Ocean at a distance of 4,500-5,000 km from the west coast of Sumatra, were severely affected by the December 26, 2004 tsunami with wave heights up to 4 m. Since the tsunami history of small islands often remains unclear due to a young historical record, it is important to study the geological traces of high energy events preserved along their coasts. We conducted a survey of the impact of the 2004 Indian Ocean tsunami on the inner Seychelles islands. In detail we studied onshore tsunami deposits in the mangrove forest at Old Turtle Pond in the Curieuse Marine National Park on the east coast of Curieuse Island. It is thus protected from anthropogenic interference. Towards the sea it was shielded until the tsunami in 2004 by a 500 m long and 1.5 m high causeway which was set up in 1909 as a sediment trap and assuring a low energetic hydrodynamic environment for the protection of the mangroves. The causeway was destroyed by the 2004 Indian Ocean Tsunami. The tsunami caused a change of habitat by the sedimentation of sand lobes in the mangrove forest. The dark organic rich mangrove soil (1.9 ?) was covered by bimodal fine to medium carbonate sand (1.7-2.2 ?) containing coarser carbonate shell fragments and debris. Intertidal sediments and the mangrove soil acted as sources of the lobe deposits. The sand sheet deposited by the tsunami is organized into different lobes. They extend landwards to different inundation distances as a function of the morphology of the onshore area. The maximum extent of 180 m from the shoreline indicates the minimum inundation distance to the tsunami. The top parts of the sand lobes cover the pneumatophores of the mangroves. There is no landward fining trend along the sand lobes and normal grading of the deposits is rare, occurring only in 1 of 7 sites. The sand lobe deposits also lack sedimentary structures. On the surface of the sand lobes numerous mostly fragmented shells of bivalves and molluscs were distributed up to 150 m from the coastline. Intact bivalve shells were mostly found positioned with the convex side upwards. On small ledges of a granitic body at 130-150 m from the shore mostly fragmented and gravel sized shells were deposited at different elevations up to 4 m above sea level. This implies a run up height of at least 4 m above sea level up to 150 m from the present shoreline.
Nentwig, Vanessa; Bahlburg, Heinrich; Monthy, Devis
Full Text Available Livelihoods in Sri Lanka have been affected not only by the initial devastation of the tsunami but also by the policies and practices of the government and the humanitarian aid community’s post-disaster response.
Tsunami induced by earthquakes typically evolves shore-ward with a significant amplification of amplitude during the last stages of shoaling. This study focuses on tsunami evolution in shallow water under the effects of the oceanographic environment such as breaking and tsunami- swell interaction. One generally describes wave breaking directly with a discontinuity in the solution to the classical nonlinear shallow water equations (NLSW) (e.g., Stoker 1985). This wave-front steepness calculation, however, has the potential problem that for the case of the single wave defined by solitary wave, breaking occurs much closer to the wave crest so that the method is formally invalid (Madsen et. al. 2008). Li and Raichlen (2002) applied a weighted essentially non-oscillatory (WENO) shock-capturing scheme in the numerical NSWE model to capture the wave breaking process. The problem arises that a convenient hamiltonian formalism is lacking to describe wave breaking. One wants to evaluate breaking by deducing the decay of the tsunami energy in a straightforward manner. The linear effect of the tsunami background circulation on swell is well known (e.g., Madsen et. al. 2008). However, Kaihatu and El Safty(2011) hypothesized that this is only one "half" of the mutual interaction between the tsunami and the overlying swell field, which might have subtle effects on the tsunami front-face steepness and breaking process. These effects were observed in a laboratory experiments (Kaihatu and El Safty 2011). It was observed that the presence of swell affects the maximum surface amplitude of overall wave field and produces significant energy shifts to high frequencies, thus promoting tsunami breaking. The theoretical study for tsunami-swell interaction requires a phase-resolving wave-wave interaction model. In this study, we derive a Hamiltonian formulation for the tsunami-swell interaction using the quasi stream-function formulation. This formalism is better able to handle uneven bathymetries than the velocity potential formalism (Kirby 1984). The resulting quadratic Hamiltonian provides a framework for description of tsunami propagating over swell and evaluates wave breaking by calculating the decay of wave energy spectra. It also allows us to explore higher order interactions between tsunami and swell. Current efforts focus on the analysis of tsunami-swell laboratory data from Kaihatu et al. (2011). These data were taken in the Tsunami Wave Basin at Oregon State University. The water depth at the wavemaker was 75cm. A 30cm solitary wave was superimposed with random swell of 2 or 4 sec. peak period and 5 or 10 cm significant wave height; both the tsunami and swell were run together and in isolation, and allowed to propagate over a sloping bottom. Time series of free surface elevations and near bottom velocities were taken at 22 gage locations in the tank. The wave signal will be separated into the tsunami and swell parts, and the transform and decay of the energy spectrum will be calculated using our formulation.
TIAN, M.; Sheremet, A.; Kaihatu, J. M.
This compilation contains annotated citations to nearly 3000 tsunami-related publications from 1962 to 1976 in English and several other languages. The foreign-language citations have English titles and abstracts
Tsunamis and hurricanes have had a devastating impact on the population living near the coast during the year 2005. The calculation of the power and intensity of tsunamis and hurricanes are of great importance not only for engineers and meteorologists but also for governments and insurance companies. This book presents new research on the mathematical description of tsunamis and hurricanes. A combination of old and new approaches allows to derive a nonlinear partial differential equation of fifth order describing the steepening up and the propagation of tsunamis. The description includes dissipative terms and does not contain singularities or two valued functions. The equivalence principle of solutions of nonlinear large gas dynamics waves and of solutions of water wave equations will be used. An extension of the continuity equation by a source term due to evaporation rates of salt seawater will help to understand hurricanes. Detailed formula, tables and results of the calculations are given.
In contrast to far-field tsunami amplitudes that are fairly well predicted by the seismic moment of subduction zone earthquakes, there exists significant variation in the scaling of local tsunami amplitude with respect to seismic moment. From a global catalog of tsunami runup observations this variability is greatest for the most frequently occuring tsunamigenic subduction zone earthquakes in the magnitude range of 7 tsunami runup scaling can be ascribed to tsunami source parameters that are independent of seismic moment: variations in the water depth in the source region, the combination of higher slip and lower shear modulus at shallow depth, and rupture complexity in the form of heterogeneous slip distribution patterns. The focus of this study is on the effect that rupture complexity has on the local tsunami wave field. A wide range of slip distribution patterns are generated using a stochastic, self-affine source model that is consistent with the falloff of far-field seismic displacement spectra at high frequencies. The synthetic slip distributions generated by the stochastic source model are discretized and the vertical displacement fields from point source elastic dislocation expressions are superimposed to compute the coseismic vertical displacement field. For shallow subduction zone earthquakes it is demonstrated that self-affine irregularities of the slip distribution result in significant variations in local tsunami amplitude. The effects of rupture complexity are less pronounced for earthquakes at greater depth or along faults with steep dip angles. For a test region along the Pacific coast of central Mexico, peak nearshore tsunami amplitude is calculated for a large number (N = 100) of synthetic slip distribution patterns, all with identical seismic moment (Mw = 8.1). Analysis of the results indicates that for earthquakes of a fixed location, geometry, and seismic moment, peak nearshore tsunami amplitude can vary by a factor of 3 or more. These results indicate that there is substantially more variation in the local tsunami wave field derived from the inherent complexity subduction zone earthquakes than predicted by a simple elastic dislocation model. Probabilistic methods that take into account variability in earthquake rupture processes are likely to yield more accurate assessments of tsunami hazards.
California is the first US State to complete its tsunami inundation mapping. A new generation of tsunami inundation maps is now available for 17 coastal counties.. The new maps offer improved coverage for many areas, they are based on the most recent descriptions of potential tsunami farfield and nearfield sources and use the best available bathymetric and topographic data for modelling. The need for new tsunami maps for California became clear since Synolakis et al (1998) described how inundation projections derived with inundation models that fully calculate the wave evolution over dry land can be as high as twice the values predicted with earlier threshold models, for tsunamis originating from tectonic source. Since the 1998 Papua New Guinea tsunami when the hazard from offshore submarine landslides was better understood (Bardet et al, 2003), the State of California funded the development of the first generation of maps, based on local tectonic and landslide sources. Most of the hazard was dominated by offshore landslides, whose return period remains unknown but is believed to be higher than 1000 years for any given locale, at least in Southern California. The new generation of maps incorporates local and distant scenarios. The partnership between the Tsunami Research Center at USC, the California Emergency Management Agency and the California Seismic Safety Commission let the State to be the first among all US States to complete the maps. (Exceptions include the offshore islands and Newport Beach, where higher resolution maps are under way). The maps were produced with the lowest cost per mile of coastline, per resident or per map than all other States, because of the seamless integration of the USC and NOAA databases and the use of the MOST model. They are a significant improvement over earlier map generations. As part of a continuous improvement in response, mitigation and planning and community education, the California inundation maps can contribute in reducing tsunami risk. References -Bardet, JP et al (2003), Landslide tsunamis: Recent findings and research directions, Pure and Applied Geophysics, 160, (10-11), 1793-1809. -Eisner, R., Borrero, C., Synolakis, C.E. (2001) Inundation Maps for the State of California, International Tsunami Symposium, ITS 2001 Proceedings, NHTMP Review Paper #4, 67-81. -Synolakis, C.E., D. McCarthy, V.V. Titov, J.C. Borrero, (1998) Evaluating the Tsunami Risk in California, CALIFORNIA AND THE WORLD OCEAN '97, 1225-1236, Proceedings ASCE, ISBN: 0-7844-0297-3.
Barberopoulou, Aggeliki; Borrero, Jose; Uslu, Burak; Kanoglu, Utku; Synolakis, Costas
In the early 1980s, the United States National Oceanic and Atmospheric Administration Pacific Marine Environmental Laboratory established the fundamentals of the contemporary tsunameter network deployed throughout the world oceans. The decades of technological and scientific advancements that followed led to a robust network that now provides real-time deep-ocean tsunami observations routinely incorporated into operational procedures of tsunami warning centers around the globe. All aspects of the network, from research to operations, to data archive and dissemination, are conducted collaboratively between the National Data Buoy Center, the Pacific Marine Environmental Laboratory, and the National Geophysical Data Center, with oversight by the National Weather Service. The National Data Buoy Center manages and conducts all operational network activities and distributes real-time data to the public. The Pacific Marine Environmental Laboratory provides the research component in support of modeling and network enhancements for improved forecasting capability. The National Geophysical Data Center is responsible for the processing, archiving, and distribution of all retrospective data and integrates DART® tsunameter data with the National Geophysical Data Center global historical tsunami database. The role each agency plays in collecting, processing, and disseminating observations of deep-ocean bottom pressure is presented along with brief descriptions of data processing procedures. Specific examples of challenges and the approaches taken to address these are discussed. National Geophysical Data Center newly developed and available tsunami event web pages are briefly described and demonstrated with processed data for both the Tohoku 11 March 2011 and the Haiti 12 January 2010 tsunami events.
Mungov, George; Eblé, Marie; Bouchard, Richard
An innovative newly developed modular and standards based Decision Support System (DSS) is presented which forms part of the German Indonesian Tsunami Early Warning System (GITEWS). The GITEWS project stems from the effort to implement an effective and efficient Tsunami Early Warning and Mitigation System for the coast of Indonesia facing the Sunda Arc along the islands of Sumatra, Java and Bali. The geological setting along an active continental margin which is very close to densely populate...
Steinmetz, T.; Raape, U.; Teßmann, S.; Strobl, C.; Friedemann, M.; Kukofka, T.; Riedlinger, T.; Mikusch, E.; Dech, S.
Ionosphere is the layer of the atmosphere from about 85 to 600km containing electrons and electrically charged atoms that are produced by solar radiation. Perturbations - layering affected by day and night, X-rays and high-energy protons from the solar flares, geomagnetic storms, lightning, drivers-from-below. Strategic for radio-wave transmission. This project discusses the inversion of ionosphere signals, tsunami wave amplitude and coupling parameters, which improves tsunami warning systems.
Ionosphere is the layer of the atmosphere from about 85 to 600km containing electrons and electrically charged atoms that are produced by solar radiation. Perturbations - layering affected by day and night, X-rays and high-energy protons from the solar flares, geomagnetic storms, lightning, drivers-from-below. Strategic for radio-wave transmission. This project discusses the inversion of ionosphere signals, tsunami wave amplitude and coupling parameters, which improves tsunami warning systems.
Larmat, Carene [Los Alamos National Laboratory
Full Text Available This article focuses on the effect of dispersion in the field of tsunami modeling. Frequency dispersion in the linear long-wave limit is first briefly discussed from a theoretical point of view. A single parameter, denoted as "dispersion time", for the integrated effect of frequency dispersion is identified. This parameter depends on the wavelength, the water depth during propagation, and the propagation distance or time. Also the role of long-time asymptotes is discussed in this context. The wave generation by the two main tsunami sources, namely earthquakes and landslides, are briefly discussed with formulas for the surface response to the bottom sources. Dispersive effects are then exemplified through a semi-idealized study of a moderate-strength inverse thrust fault. Emphasis is put on the directivity, the role of the "dispersion time", the significance of the Boussinesq model employed (dispersive effect, and the effects of the transfer from bottom sources to initial surface elevation. Finally, the experience from a series of case studies, including earthquake- and landslide-generated tsunamis, is presented. The examples are taken from both historical (e.g. the 2011 Japan tsunami and the 2004 Indian Ocean tsunami and potential tsunamis (e.g. the tsunami after the potential La Palma volcanic flank collapse. Attention is mainly given to the role of dispersion during propagation in the deep ocean and the way the accumulation of this effect relates to the "dispersion time". It turns out that this parameter is useful as a first indication as to when frequency dispersion is important, even though ambiguity with respect to the definition of the wavelength may be a problem for complex cases. Tsunamis from most landslides and moderate earthquakes tend to display dispersive behavior, at least in some directions. On the other hand, for the mega events of the last decade dispersion during deep water propagation is mostly noticeable for transoceanic propagation.
Full Text Available The generation and propagation of the November 1, 1755 Lisbon earthquake generated tsunami is of current interest to the IOCARIBE Tsunami Scientific Steering Committee.The November 1, 1755 Lisbon earthquake generated a tsunami with a period of one hour and amplitudes of 20 meters at Lisbon and along the African and south European coasts, of 4 meters along the English coast, and of 7 meters at Saba in the Caribbean after 7 hours of travel. The modeling was performed using the SWAN code which solves the nonlinear long wave equations. The tsunami generation, and propagation was modeled using a 10. minute Mercator grid of 600 by 640 cells. The observed tsunami wavecharacteristics were approximatelyreproduced usinga source 300 kilometer in radius with a drop of 30 meters located in the region of the 1969 earthquake near the Gorringe bank. The east coast of the U.S.A. and the Caribbean received a tsunami wave off shore in deep water about 2 meters high with periods of 1.25 to 1.5 hours. The maximum wave amplitude after run-up would be about 10 feet. The Gulf of Mexico would have a wave with less than half that amplitude.
Charles L. Mader
The devastating impacts of the 2004 Indian Ocean tsunami highlighted the need for an effective end-to-end tsunami early warning system in the region that connects the scientific components of warning with preparedness of institutions and communities to respond to an emergency. Essential to preparedness planning is knowledge of tsunami risks. In this study, development of an online tool named “INSPIRE” for tsunami inundation simulation and tsunami loss estimation is presented. The tool is designed to accommodate various accuracy levels of tsunami exposure data which will support the users to undertake preliminary tsunami risk assessment from the existing data with progressive improvement with the use of more detailed and accurate datasets. Sampling survey technique is introduced to improve the local vulnerability data with lower cost and manpower. The performance of the proposed methodology and the INSPIRE tool were tested against the dataset in Kamala and Patong municipalities, Phuket province, Thailand. The estimated building type ratios from the sampling survey show the satisfactory agreement with the actual building data at the test sites. Sub-area classification by land use can improve the accuracy of the building type ratio estimation. For the resulting loss estimation, the exposure data generated from detailed field survey can provide the agreeable results when comparing to the actual building damage recorded for the Indian Ocean tsunami event in 2004. However, lower accuracy exposure data derived from sampling survey and remote sensing can still provide a comparative overview of estimated loss.
Srivihok, P.; Honda, K.; Ruangrassamee, A.; Muangsin, V.; Naparat, P.; Foytong, P.; Promdumrong, N.; Aphimaeteethomrong, P.; Intavee, A.; Layug, J. E.; Kosin, T.
With this volume of the Pure and Applied Geophysics (PAGEOPH) topical issue "Tsunamis in the Pacific Ocean: 2011-2012", we are pleased to present 21 new papers discussing tsunami events occurring in this two-year span. Owing to the profound impact resulting from the unique crossover of a natural and nuclear disaster, research into the 11 March 2011 Tohoku, Japan earthquake and tsunami continues; here we present 12 papers related to this event. Three papers report on detailed field survey results and updated analyses of the wave dynamics based on these surveys. Two papers explore the effects of the Tohoku tsunami on the coast of Russia. Three papers discuss the tsunami source mechanism, and four papers deal with tsunami hydrodynamics in the far field or over the wider Pacific basin. In addition, a series of five papers presents studies of four new tsunami and earthquake events occurring over this time period. This includes tsunamis in El Salvador, the Philippines, Japan and the west coast of British Columbia, Canada. Finally, we present four new papers on tsunami science, including discussions on tsunami event duration, tsunami wave amplitude, tsunami energy and tsunami recurrence.
Rabinovich, Alexander B.; Borrero, Jose C.; Fritz, Hermann M.
The Mediterranean Sea region is characterized by near-field tsunamis (travel times less than 30 min.). An efficient end-to-end warning system should fulfill the condition that the time needed from an earthquake detection to evacuation is less than the arrival time of the first wave, which is a very hard task in the Mediterranean. The project NEARTOWARN, which is supported by the EU DG-ECHO prevention program aims, among others, to establish a pilot system in Rhodes island, SE Aegean Sea, Greece, with the purpose to meet needs for local tsunami early warning but applicable in other coastal zones of the Mediterranean and beyond. To minimize emergency time in less than 30 sec, seismic alert devices (SEDs) make the core component of alerting. SEDs are activated and send alerting signals as soon as a P- phase of seismic wave is detected in the near-field domain and for a predetermined threshold of ground motion. Then, emergency starts while SEDs activate remotely other devices, such as computers with data bases of pre-calculated tsunami simulations, surveillance cameras etc. The system is completed with tide- gauges, simulated tsunami scenarios and emergency planning supported by a Geographical Management System. Rhodes island in Dodecanese, Greece, has been selected as a test- area for the development of the prototype system. To promote the future development of such local systems in other coastal zones of the Mediterranean the NEARTOWARN partners review current status of early warning systems, produce digital inventories of wave travel times from several tsunami sources to a number of forecasting points, standardize data bases for pre-simulated tsunami scenarios and optimize triggering thresholds for the SED alerting networks. A local system such as the one developed by NEARTOWARN is expected to function in synergy with national and regional warning systems such as the one coordinated NEAMTWS.
Papadopoulos, Gerasimos; Karastathis, Vasilis; Novikova, Tatyana; Fokaefs, Anna; Minadakis, George; Papageorgiou, Antonia; Tinti, Stefano; Armigliato, Alberto; Ausilia Paparo, Maria; Zaniboni, Filippo; Georgiou, George; Aniel Quiroga, Inigo; Gonzalez, Mauricio; Alvarez-Gomez, Jose Antonio; Lesne, Olivia; Renou, Camille; Mangin, Antoine; Schindele, Francois; Argyris, Ilias
Tsunami Probabilistic Risk Assessment (PRA) standard was issued in February 2012 by Standard Committee of Atomic Energy Society of Japan (AESJ). This article detailed tsunami fragility analysis, which calculated building and structure damage probability contributing core damage and consisted of five evaluation steps: (1) selection of evaluated element and damage mode, (2) selection of evaluation procedure, (3) evaluation of actual stiffness, (4) evaluation of actual response and (5) evaluation of fragility (damage probability and others). As an application example of the standard, calculation results of tsunami fragility analysis investigation by tsunami PRA subcommittee of AESJ were shown reflecting latest knowledge of damage state caused by wave force and others acted by tsunami from the 'off the Pacific Coast of Tohoku Earthquake'. (T. Tanaka)
Full Text Available The main goal of this study is to give the preliminary estimates of the tsunami risks for the Lesser Antilles. We investigated the available data of the tsunamis in the French West Indies using the historical data and catalogue of the tsunamis in the Lesser Antilles. In total, twenty-four (24 tsunamis were recorded in this area for last 400 years; sixteen (16 events of the seismic origin, five (5 events of volcanic origin and three (3 events of unknown source. Most of the tsunamigenic earthquakes (13 occurred in the Caribbean, and three tsunamis were generated during far away earthquakes (near the coasts of Portugal and Costa Rica. The estimates of tsunami risk are based on a preliminary analysis of the seismicity of the Caribbean area and the historical data of tsunamis. In particular, we investigate the occurrence of historical extreme runup tsunami data on Guadeloupe, and these data are revised after a survey in Guadeloupe.
The paper presents results of tsunami wave modelling based on different analytical/numerical approaches with shallow water wave theory. The results of in-house finite element code Tsunami Solution(TSUSOL) is highlighted through numerical simulation of Sumatra-2004 and Makran-1945 tsunami events. The TSUSOL code is shown to have special capability of coupled tsunami and acoustic wave simulation, which is an important feature for the early warning system
The area of the Caribbean Sea is geologically active. Earthquakes and volcanoes are common occurrences. These geologic events can generate powerful tsunamis some of which are more devastating than the earthquake or volcanic eruption itself. This document lists brief descriptions of 91 reported waves that might have been tsunamis within the Caribbean region. Of these, 27 are judged by the authors to be true, verified tsunamis and an additional nine are considered to be very likely true tsunami...
Lockridge, Patricia A.; LowellS. Whiteside; Lander, James F.
On July 17, 1998, an earthquake registering 7.1 on the richter scale caused a tsunami along the coast of Papua New Guinea, wiping out two villages. The US Geological Survey (USGS) provides a model of the tsunami along with background information and news stories about the event. The animation is available in four formats and resolutions. Those who want to learn more about tsunamis can take advantage of the site's links under the heading General Information about Tsunamis.
Following an earthquake a tsunami warning center (TWC) must determine if a coastal evacuation is necessary and must do so fast enough for the warning to be useful to affected coastlines. Once a damaging tsunami has arrived, the TWC must decide when to cancel its warning, a task often more challenging than the initial hazard assessment. Here we demonstrate the difficulties by investigating the impact of the Tohoku tsunami of 11 March 2011 on the State of Hawaii, which relies on the Pacific Tsunami Warning Center (PTWC) for tsunami hazard guidance. PTWC issued a Tsunami Watch for Hawaii at 10 March 1956 HST (10 minutes after the earthquake) and upgraded to a Tsunami Warning at 2131 HST. The tsunami arrived in Hawaii just before 0300 HST the next day, reached a maximum runup of over 5 m, and did roughly $50 million in damage throughout the state. PTWC downgraded the Warning to an Advisory at 0730 HST, and canceled the Advisory at 1140 HST. The timing of the downgrade was appropriate—by then it was safe for coastal residents to re-enter the evacuation zone but not to enter the water—but in retrospect PTWC cancelled its Advisory too early. By late morning tide gauges throughout the state had all registered maximum wave heights of 30 cm or less for a couple of hours, so PTWC cancelled. The Center was unaware, however, of ocean behavior at locations without instruments. At Ma'alaea Harbor on the Island of Maui, for example, sea level oscillations exposed the harbor bottom every 20 minutes for several hours after the cancellation. At Waikiki on Oahu, lifeguards rescued 25 swimmers (who had either ignored or were unaware of the cancellation message's caution about hazardous currents) in the hours after the cancellation and performed CPR on one near-drowning victim. Fortunately, there were no deaths. Because of dangerous surges, ocean safety officials closed Hanauma Bay, a popular snorkeling spot on Oahu, for a full day after the tsunami hit. They reassessed the bay the following morning just as waves reflected from South America started to arrive (36 hours after the earthquake), and prudently chose to keep the bay closed for two further days. The Tohoku tsunami showed that resonances and trapped waves in shallow water can last for many hours and that energy reflected from distant shorelines can rejuvenate them. PTWC's real-time simulation of the tsunami, including animation of its propagation, now helps to identify which reflections will be most troublesome and should permit the Center to specify in advance how long a Warning should remain in effect. The current open-ended warnings, which specify when the tsunami will arrive but not how long the Warning should last, should be replaced with warnings active for a specified time ("until 3 a.m. tomorrow"), with PTWC adjusting the projected cancellation time based on coastal sea-level observations. Such warnings should greatly reduce public misconceptions and state and local government expectations about how long the hazard will last. The National Weather Service, parent agency of the US TWCs, already issues weather Warnings and Advisories active for specific durations, so this message format is already familiar to both the public and emergency managers.
Fryer, G. J.; Becker, N. C.; Wang, D.; Weinstein, S.; Richards, K.
The present report introduces main results of investigations on precise tsunami evaluation methods, which were carried out from the viewpoint of safety evaluation for nuclear power facilities and deliberated by the Tsunami Evaluation Subcommittee. A framework for the probabilistic tsunami hazard analysis (PTHA) based on logic tree is proposed and calculation on the Pacific side of northeastern Japan is performed as a case study. Tsunami motions with dispersion and wave breaking were investigated both experimentally and numerically. The numerical simulation method is verified for its practicability by applying to a historical tsunami. Tsunami force is also investigated and formulae of tsunami pressure acting on breakwaters and on building due to inundating tsunami are proposed. (author)
Eighteen papers on past and recent destructive tsunamis are included in Volume II of the PAGEOPH topical issue "Historical and Recent Catastrophic Tsunamis in the World." Three papers discuss deep-sea (DART) and coastal tsunami observations, warning systems and risk management in the Pacific Ocean. Four papers examine the 1755 Lisbon, 1964 Alaska, 2003 Algeria, and 2011 Haiti tsunamis. Four more papers, as well as some papers in Volume I, report on various aspects of the 2010 Chile tsunami. Two papers present some results of field survey and modelling investigation of the 2010 Mentawai, Indonesia, tsunami. Three papers report on modelling efforts of tsunami generation by earthquake and landslide, and of tsunami propagation. Finally, two papers discuss hazard assessment using a probabilistic approach.
Satake, Kenji; Rabinovich, Alexander B.; Dominey-Howes, Dale; Borrero, José C.
Tsunamis can last a long time compared to the geophysical events that generate them. The Tohoku, Japan tsunami of March 11, 2011 was an extreme event that continued to disturb the Pacific Ocean for many days following its initiation. Historically Japan was considered a source of low tsunami wave energy for the US West Coast. However, damage in California from the last great Japan tsunami was second to that suffered during the 1964 Alaska earthquake. Computer animations of the catastrophic Japan tsunami and other recent significant tsunamis combined with seismological techniques help to identify multiple paths of tsunami waves refracted and reflected by complex bathymetry across the Pacific Ocean basin. Using recent large tsunamigenic earthquakes we demonstrate that the long duration and damage noticed during the last great Japan tsunami in the farfield is a result of several factors. Waveguides acting as tsunami lenses and mirrors, including continental margins, direct the tsunami wave energy to diverse locations around the ocean basin; directionality affected by islands and seamounts, large reflections off of South America, bathymetric features far and near the area of impact and shelf geometry may delay and further amplify the main tsunami energy. This has direct implications on the prediction of tsunami impacts since the US West Coast appears to receive maximum waves much later than first wave arrivals.
Barberopoulou, A.; Legg, M. R.; Gica, E.; Legg, G.
This page features USGS visualizations including a slide show of the sudden movement of the Pacific tectonic plate under the North American plate caused a massive earthquake and a tsunami. It also contains maps of the magnitude of shaking and predicted tsunami wave heights from the March 11, 2011 earthquake and tsunami in Japan.
Times, New Y.
We study the 2010 Mentawai earthquake, a tsunami earthquake that occurred seaward of the southern Mentawai islands of Sumatra, and produced a locally devastating tsunami, with runup commonly in excess of 6 m. As a unique tsunami earthquake case, there is a significant discrepancy between the observed small GPS displacement and the very large tsunami runup (maximum value > 16 m), which cannot be explained by the conventional GPS or seismic inversion model. The goal of this work is to infer ...
Li, L.; Huang, Z.
The Hikurangi subduction margin, where the Pacific Plate subducts beneath the North Island of New Zealand, poses a major seismic and tsunami hazard to the New Zealand region, but its seismic and tsunami potential is largely unknown because of New Zealand's short (< 170 years) historical record of seismicity. This article discusses the implications of results from GPS, paleoseismology, and tsunami modeling studies for understanding Hikurangi subduction earthquake and tsunami potential. Paleose...
Wallace, Laura M.; Cochran, Ursula A.; Power, William L.; Clark, Kate J.
Data on tsunami phenomena occurring in the East Hellenic Arc and Trench system (HA-T) from antiquity up to the present have been updated, critically evaluated and compiled in the standard GITEC format developed in the last decade for the New European Tsunami Catalogue. New field observations are presented for the tsunamis of 9 February 1948 and 24 March 2002. From the 18 tsunamis reported eight are rather well-documented while another nine remain doubtful. The mean recurrence of strong tsunam...
Papadopoulos, G. A.; Daskalaki, E.; Fokaefs, A.; Giraleas, N.
Paleotsunami deposits may prove harder to find in tidal wetlands and beach-ridge plains around the tropical Indian Ocean than in temperate but otherwise comparable settings on the Pacific Rim. The reasons for this challenge are probably unrelated to tsunami size or recurrence. Estuarine marshes and grassy beach-ridge plains provide widespread opportunities for tsunamis to lay down preservable sand sheets in northeastern Japan, Kamchatka, the northwestern United States, and south-central Chile. The small plants of these lowlands offered little resistance to tsunami flow. Coseismic subsidence and net late Holocene submergence provided caps of tidal mud that help preserve the sand. By contrast in tidal wetlands overrun by the 2004 Indian Ocean tsunami, mangrove swamps and their inhibit the formation and preservation of tsunami sand sheets. For example, in mangrove swamps along tidal inlets near Ban Nam Kem and Tab Lamu, Thailand, sandy deposits of the 2004 tsunami were probably limited to feather- shaped channel-margin areas where the tsunami lost much of its momentum to the toppling of leafy trees. When these deposits were examined in July 2006, deposit-feeding crabs were busily mixing the sand into muddy, peaty mangrove soils. Such limitations of mangrove swamps as paleotsunami recorders may help explain why a reconnaissance in May 2006 turned up no sand sheets in the soils of mangroves near Cilacap, on the south coast of Java. Thus far it is unclear whether this coast, which faces the Sunda Trench, lacks potential for tsunamis as enormous as Aceh's in 2004, or whether it has a history of enormous tsunamis that simply failed to leave a long-lasting record in the Cilacap mangroves. Disturbance by humans limits the paleotsunami targets on beach-ridge plains facing the Indian Ocean. Thai coastal plains, though apparently grassy where undisturbed, have been extensively modified by placer mining for tin. In Java and southeastern India, most coastal plains have been under the plow for centuries. The outlook for paleotsunami hunting in South and Southeast Asia probably depends on new targets that include coral boulders and scarcely disturbed beach-ridge plains in Thailand; archaeological sites that provide cultural timelines in India; lagoons of Sri Lanka; coastal rivers that offer cutbanks and oxbows on beach-ridge plains of Java; delicately laminated deposits of salt flats routinely overrun by storm surges on the arid northern shores of the Arabian Sea; and records of prehistoric land-level change close to fault-rupture areas along the Sunda Trench.
Atwater, B. F.
Full Text Available A model-based tsunami prediction system has been developed as part of the French Tsunami Warning Center (operational since 1 July 2012. It involves a precomputed unit source functions database (i.e., a number of tsunami model runs that are calculated ahead of time and stored. For the Mediterranean basin, the faults of the unit functions are placed adjacent to each other, following the discretization of the main seismogenic faults. An automated composite scenarios calculation tool is implemented to allow the simulation of any tsunami propagation scenario (i.e., of any seismic moment. Uncertainty on the magnitude of the detected event and inaccuracy of the epicenter location are taken into account in the composite scenarios calculation. Together with this forecasting system, another operational tool based on real time computing is implemented as part of the French Tsunami Warning Center. This second tsunami simulation tool takes advantage of multiprocessor approaches and more realistic seismological parameters, once the focal mechanism is established. Three examples of historical earthquakes are presented, providing warning refinement compared to the rough tsunami risk map given by the model-based decision matrix.
This chapter establishes the relationship among earthquake source parameters and the generation, propagation, and run-up of local tsunamis. In general terms, displacement of the seafloor during the earthquake rupture is modeled using the elastic dislocation theory for which the displacement field is dependent on the slip distribution, fault geometry, and the elastic response and properties of the medium. Specifically, nonlinear long-wave theory governs the propagation and run-up of tsunamis. A parametric study is devised to examine the relative importance of individual earthquake source parameters on local tsunamis, because the physics that describes tsunamis from generation through run-up is complex. Analysis of the source parameters of various tsunamigenic earthquakes have indicated that the details of the earthquake source, namely, nonuniform distribution of slip along the fault plane, have a significant effect on the local tsunami run-up. Numerical methods have been developed to address the realistic bathymetric and shoreline conditions. The accuracy of determining the run-up on shore is directly dependent on the source parameters of the earthquake, which provide the initial conditions used for the hydrodynamic models.
Geist, Eric L.
The various uncertainties in the earthquake-triggered tsunami threat assessment are difficult to quantify and/or integrate into the tsunami early warning process. Uncertainties in the (seismic) input parameters and the lack of knowledge about the earthquake slip distribution contribute most to the total uncertainty in real-time evaluated tsunami assessment. We present a method how to integrate and quantify these uncertainties in the warning process by evaluating a tsunami warning level probability distribution with a Bayesian network (BN) approach. As soon as an earthquake is detected, the seismic source parameter estimates are evaluated and a probabilistic overview on different tsunami warning levels is provided, feasible to support a decision maker at a warning center with important additional data. A BN system has been developed exemplarily for the region Sumatra. In this paper, we describe the method of BN generation by ancestral sampling, we critically analyse the assumptions made and weight the pro and cons of the BN approach. A case study demonstrates the workflow of the BN system in real-time and reveals the promising power of a BN analysis in the framework of early warning.
Blaser, L.; Ohrnberger, M.; Riggelsen, C.; Babeyko, A.; Scherbaum, F.
The Alaska Tsunami Warning Center (ATWC) has implemented many major changes in order to provide timely and effective tsunami warning services for coastal populations in Alaska, and the west coasts of Canada and the lower 48 States. The basis for these improvements was the integration of computers and associated developments into the ATWC's operations. New concepts, technique developments, procedures, computers, and equipment were implemented which resulted in a highly automated warning system which analyzes data from potential tsunamigenic earthquakes in real-time, and immediately disseminates necessary critical information to affected coastal populations. These advancements are leading toward an automated expert system. The present system has been exercised for seven recent potential tsunamigenic earthquakes and has proven to be very timely with tsunami warnings being issued in an average of 11 minutes after the origin time of an earthquake. Seismic and tide data networks have been enlarged to improve the accuracy and timeliness in locating and sizing earthquakes, and for confirming the existence of a tsunami. New techniques and equipment are being implemented to collect, analyze and process tide data via micro computers. All critical warning and watch information messages are generated by computers which are linked to a satellite and high speed teletypewriter communication systems for rapid dissemination of information. The ATWC's community preparedness efforts haveATWC's community preparedness efforts have been expanded to aid those individuals who may be caught in the immediate vicinity of a violent earthquake and its subsequent tsunami. (author). 14 refs, 6 figs
Over 75 tsunamis have been documented in the Caribbean and Adjacent Regions during the past 500 years. Since 1500, at least 4484 people are reported to have perished in these killer waves. Hundreds of thousands are currently threatened along the Caribbean coastlines. In 2005 the Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) was established. It recommended the following minimum seismic performance standards for the detection and analysis of earthquakes: 1) Earthquake detection within 1 minute, 2) Minimum magnitude threshold = M4.5, and 3) Initial hypocenter error of Caribbean and Adjacent Regions. The NOAA National Weather Service Caribbean Tsunami Warning Program prepares and distributes monthly reports on real time and archived seismic data availability of the contributing stations at the US Tsunami Warning Centers, the Puerto Rico Seismic Network and IRIS. As of early 2014, 99 of the proposed stations are being contributed by national, regional and international seismological institutions. Recent network additions (Nicaragua, Colombia, Mexico, Cayman Islands, and Venezuela) have reduced detection threshold, time and location error throughout much of the Caribbean region and Central America. Specifically, earthquakes (>M4.0) can be detected within 1 minute throughout much of the Caribbean. The remaining exceptions to this standard for detection are portions of northern South America and Mexico. Another performance criterion is 90% data availability. Currently 60-70% of the stations meet this standard. The presentation will further report on the status of the CARIBE EWS seismic capability for the timely and accurate detection and analysis of earthquakes for tsunami warning purposes for the Caribbean and Adjacent Regions.
Saurel, Jean-Marie; von Hillebrandt-Andrade, Christa; Crespo, Hector; McNamara, Dan; Huerfano, Victor
Approximately 70 minutes after the great Sumatra-Andaman Islands earthquake of 26 December 2004 and 40 to 130 minutes before the tsunami's arrival, the ground at three island stations in the Indian Ocean started to shake at periods comparable to those of the tsunami waves (~1000 s). The characteristics and timing of these very-long period waves are not those of the normal seismic phases generated by earthquakes, and strongly suggest ground deformation excited by the tsunami waves in a way similar to the generation of seismic waves by the oscillation of a heavy mass pressed against the ground, a technique often used in geophysical exploration. The arrival times of these anomalous waves are consistent with the paths of tsunami-excited seismic waves, along which the tsunami slammed into the east coast of the Indian Ocean and generated seismic waves, which then propagated in the solid earth at a velocity higher than that of the tsunami to the stations in the Indian Ocean. The observation of the same very-long period wave at Hainan, China, at the time expected for the tsunami-excited seismic waves to propagate from the west coast of northern Sumatra, reconfirms our interpretation. We can rule out the possibility that the anomalous long-period waves are the fundamental-mode wave and overtones propagating along the major arcs, because the predicted times are opposite to the observation. Additional studies are required to further understand the coupling between tsunami waves and the solid earth and the manner in which that knowledge might be used to reduce the loss and suffering in future tsunamis.
Full Text Available A new model for the global tsunami computation is constructed. It includes a high order of approximation for the spatial derivatives. The boundary condition at the shore line is controlled by the total depth and can be set either to runup or to the zero normal velocity. This model, with spatial resolution of one minute, is applied to the tsunami of 26 December 2004 in the World Ocean from 80?S to 69?N. Because the computational domain includes close to 200 million grid points, a parallel version of the code was developed and run on a supercomputer. The high spatial resolution of one minute produces very small numerical dispersion even when tsunamis wave travel over large distances. Model results for the Indonesian tsunami show that the tsunami traveled to every location of the World Ocean. In the Indian Ocean the tsunami properties are related to the source function, i.e., to the magnitude of the bottom displacement and directional properties of the source. In the Southern Ocean surrounding Antarctica, in the Pacific, and especially in the Atlantic, tsunami waves propagate over large distances by energy ducting over oceanic ridges. Tsunami energy is concentrated by long wave trapping over the oceanic ridges. Our computations show the Coriolis force plays a noticeable but secondary role in the trapping. Travel times obtained from computations as arrival of the first significant wave show a clear and consistent pattern only in the region of the high amplitude and in the simply connected domains. The tsunami traveled from Indonesia, around New Zealand, and into the Pacific Ocean. The path through the deep ocean to North America carried miniscule energy, while the stronger signal traveled a much longer distance via South Pacific ridges. The time difference between first signal and later signals strong enough to be recorded at North Pacific locations was several hours.
Correctly characterizing tsunami source generation is the most critical component of modern tsunami forecasting. Although difficult to quantify directly, a tsunami source can be modeled via different methods using a variety of measurements from deep-ocean tsunameters, seismometers, GPS, and other advanced instruments, some of which in or near real time. Here we assess the performance of different source models for the destructive 11 March 2011 Japan tsunami using model-data comparison for the generation, propagation, and inundation in the near field of Japan. This comparative study of tsunami source models addresses the advantages and limitations of different real-time measurements with potential use in early tsunami warning in the near and far field. The study highlights the critical role of deep-ocean tsunami measurements and rapid validation of the approximate tsunami source for high-quality forecasting. We show that these tsunami measurements are compatible with other real-time geodetic data, and may provide more insightful understanding of tsunami generation from earthquakes, as well as from nonseismic processes such as submarine landslide failures.
Wei, Yong; Newman, Andrew V.; Hayes, Gavin P.; Titov, Vasily V.; Tang, Liujuan
Protected areas can represent a strategic laboratory for the realisation of initiatives capable of promoting sustainable economic development models at a local level. One of the duties of national parks is to provide value and promote, even for tourism purposes, natural, historical and cultural resources subject to restrictions in the territory. This contribution describes the research process activated for the definition of a tourism development strategy in the youngest Italian national park...
Bencivenga, Angelo; Breil, Margaretha; Cassinelli, Mariaester; Chiarullo, Livio; Percoco, Annalisa
This article provides with an overview of the qualitative research methods. Over last few decades, qualitative research is getting very popular in the fields of business, sociology, psychology and others. This article, in its introduction, gives a general idea about the qualitative research. Then it discusses the main differences between qualitative and quantitative research methods. The article also discusses about the ethical issues important for qualitative research. Lastly it discusses ab...
Hossain, Dewan Mahboob
The first tsunami exercise of the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas (NEAMTWS) has been conducted on 27-28 November 2012 involving 19 of the 39 member countries of the Intergovernmental Coordination Group (ICG) for NEAMTWS. NEAMWave12 involved the simulation of the assessment of a tsunami, based on an earthquake-driven scenario followed by alert message dissemination by Candidate Tsunami Watch Provider (CTWP) (Phase A) and continued with the simulation of the National Tsunami Warning Center's/Tsunami Warning Focal Point's (NTWC/TWFP) and Civil Protection Authoritie's (CPA) actions (Phase B), as soon as the message produced in Phase A has been received. There were four earthquake triggered tsunami scenarios in NEAMWave12 in different parts of the NEAM Region, where each CTWP (CENALT-France, NOA-Greece, IPMA-Portugal and KOERI-Turkey) was responsible for a single scenario. The CENALT Scenario was based on a plausible worst-case scenario of magnitude 7.5 along the Western Mediterranean Algerian margin at a fault located close to 21-22 August 1856 Jijel earthquakes. The NOA scenario was based on an earthquake similar to the well-known Amorgos earthquake, which was followed by a tsunami that devastated the Aegean Sea on 9 July 1956. The IPMA scenario was based on the 1 November 1755 Lisbon event with the assumption that the event represents the worst-case tsunami scenario impacting the NE Atlantic region. Finally, the KOERI scenario was based on a Mw=8.4 worst-case interpretation of the 8 August 1303 Crete and Dodecanese Islands earthquake resulting in destructive inundation in the Eastern Mediterranean. Initial evaluation of the exercise indicates that all CTWPs successfully participated in the exercise, where existing operational and some future prototype systems were utilized. System end-users (NTWC/TWFP/CPA) benefited from the exercise considerably, demonstrating the first successful test of the NEAMTWS Tsunami Warning Chain.
Necmioglu, Ocal; Matias Matias, Luis; Schindelé, François; Behrens, Jörn; Tinti, Stefano; Chouliaras, Gerasimos; Melis, Nicos; Carrilho, Fernando; Santoro, Francesca; Rudloff, Alexander; Crochet, Emilie; Gonzalez, Mauricio
The early warning for near-field (local) tsunamis, with travel times of no more than about 30 min. from the tsunami source to the closest coastal zones, is today a hot topic of great importance in the international effort to reduce the loss of human lives and to mitigate other tsunami risks. Particularly, in the Mediterranean region earthquakes, and more rarely volcanic eruptions and landslides, produce near-field tsunamis threatening nearly all the coastal zones but mainly those in the Hellenic Arc and Trench (South Peloponnese, Cyclades, Crete, Rhodes, SW Turkey), in the Corinth Gulf (Central Greece), in the Messina strait and the east Sicily (Italy) in the Ligurian Sea, the Algeria and the Balearic islands, in the west Mediterranean basin, and the Cyprus-Lebanon area in the easternmost Mediterranean. The North East Atlantic and Mediterranean Tsunami Warning System (NEAMTWS), which is under construction with the supervision of the Intergovernmental Oceanographic Commission, is oriented to issue warnings only in regional scales, that is for about 1 hour of tsunami propagation time. For near-field warning it is unrealistic to rely on a unique system for the entire basin. Instead, several local systems working on the basis of some joint principles but with local adjustements is the most promising solution. This is exactly the aim of the new project NEARToWARN (Near-field Tsunami Warning) which is supported by the EU DG-ECHO. Partnership includes the National Observatory of Athens (Coordinator, Greece), the University of Bologna (Italy), the University of Cyprus, the ACRI-ST (Sophia-Antipolis, France), the University of Cantabria (Spain) and the Municipility of Rhodes. The main concept is to develop a prototype local early tsunami warning system. To minimize the time for emergency in less than 30 sec, seismic alert devices (SED's) make the core component of the system. SED's are activated and send alerting signals as soon as a P-phase of seismic wave is detected in the near-field but for a predetermined threshold of ground motion. Then, emergency starts while SED's activate remotely other devices, such as computers with data bases of pre-calculated tsunami simulations, surveillance cameras etc. The system is completed with tide-gauges, simulated tsunami scenarios and emergency planning supported by a Geographical Management System. Rhodes island in Dodecanese, South Aegean Sea, Greece, has been selected as a test-area for the development of the prototype system.
Papadopoulos, G. A.
In AD 1826 sealers reported earthquake and tsunami activity in Fiordland, although contemporary or near-contemporary accounts of tsunami inundation at the time are elusive. A detailed analysis of recent sediments fom Okarito Lagoon builds on contextual evidence provided by earlier research concerning past tsunami inundation. Sedimentological, geochemical, micropalaeontological and geochronological data are used to determine palaeoenvironments before, during and after what was most probably tsunami inundation in AD 1826. The most compelling chronological control is provided by a young cohort of trees growing on a raised shoreline bench stranded by a drop in the lagoon water level following tsunami inundation. (author). 42 refs., 9 figs., 1 tab
In this multi-part activity, students study seismograms from 3 different seismic stations recording the magnitude 9.0 Sumatra earthquake of December 26th, 2004. By comparing the arrival times of the P and S waves on each seismogram, students determine the distance from the epicenter to each station. Using that data, they can accurately map the location of the epicenter and the precise time of the earthquake. After locating the epicenter, students calculate the position of the tsunami generated by the quake at one hour intervals. From those determinations, predictions are made about how much time people had before the tsunami crashed onto their shores. Finally, students investigate some of the ways people can lessen the impact of the next great tsunami.
The devastating impacts of tsunamis have received increased focus since the Indian Ocean tsunami of 2004, the most devastating tsunami in over 400 years of recorded history. This professional reference is the first of its kind: it provides a globally inclusive review of the current state of tsunami detection technology and will be a much-needed resource for oceanographers and marine engineers working to upgrade and integrate their tsunami warning systems. It focuses on the two main tsunami warning systems (TWS): International and Regional. Featured are comparative assessments of detection, monitoring, and real-time reporting technologies. The challenges of detection through remote measuring stations are also addressed, as well as the historical and scientific aspects of tsunamis.
The Boxing Day Tsunami killed 240,000 people and inundated the affected shorelines with waves reaching heights up to 30m. Tsunami Early Warning Capabilities have improved in the meantime by continuing development of modular Tsunami Early Warning Systems (TEWS). However, recent tsunami events, like the Chile 2010 and the Honshu 2011 tsunami demonstrate that the key challenge for TEWS research still lies in the timely issuing of reliable early warning messages to areas at risk, but also to other stakeholders professionally involved in the unfolding event. Until now remote sensing products for Tsunami events, including crisis maps and change detection products, are exclusively linked to those phases of the disaster life cycle, which follow after the early warning stage: Response, recovery and mitigation. The International Charter for Space and Major Disasters has been initiated by the European Space Agency (ESA) and the Centre National d'Etudes Spatiales (CNES) in 1999. It coordinates a voluntary group of governmental space agencies and industry partners, to provide rapid crisis imaging and mapping to disaster and relief organisations to mitigate the effects of disasters on human life, property and the environment. The efficiency of this approach has been demonstrated in the field of Tsunami early warning by Charter activations following the Boxing Day Tsunami 2004, the Chile Tsunami 2010 and the Honshu Tsunami 2011. Traditional single-satellite operations allow at best bimonthly repeat rates over a given Area of Interest (AOI). This allows a lot of time for image acquisition campaign planning between imaging windows for the same AOI. The advent of constellations of identical remote sensing satellites in the early 21st century resulted both in daily AOI revisit capabilities and drastically reduced time frames for acquisition planning. However, the image acquisition planning for optical remote sensing satellite constellations is constrained by orbital and communication requirements: Defined time slots exist to commandeer the tasking of image acquisitions. If such a time slot has been missed, another attempt to image an AOI again can only be attempted ca. 24 hours later, due to the sun-synchronous satellite orbits Therefore it is critical to establish automated Disaster Early Warning dissemination services for the remote sensing community, to supply them with the timeliest opportunity to trigger the tasking process for the affected AOI. For very large events like a Tsunami in the Pacific, this approach provides the chance to gain additional pre-disaster imagery as a reference for change detection. In the case of the Tohoku earthquake, an ad-hoc warning dissemination process was manually dispatched by the Centre for Geoinformation Technology (CeGIT) at the German Research Centre for Geoscience, contacting RapidEye AG, once the severity of the earthquake event had been confirmed by the GEOFON geoseismic network. RapidEye AG decided to launch an imaging campaign which yielded 78 georectified image tiles (L3A) of Honshu island during the next imaging window. Of these, 26 tiles cover the affected coastline, resulting in 16,250km² of content for crisis mapping effort such as the Humanitarian Open Street Map (OSM) Team. This data was made available by RapidEye as a part of the Charter Activiation requested by Japan on March 11 2011.  Hoja, D., Schwinger, M.,Wendleder A.,Löwe, P., Konstanski, H., Weichelt, H.: Optimised Near-Real Time Data Acquisition for Disaster Related Rapid Mapping
Löwe, Peter; Wächter, Joachim
This video footage shows the force at which the tsunami struck Japan's coast. In the fishing port of Miyako, in Iwate prefecture, boats were overturned, while video from Kamaishi city shows cars being dragged down city streets by the water. The tsunami that followed the 8.9-magnitude earthquake wreaked havoc along a huge stretch of Japan's north-east coast, sweeping far inland and devastating a number of towns and villages. Powerful aftershocks are continuing to hit the region. Footage courtesy of TV Asahi and TBS
In this paper, we use the approximation of shallow water waves (Margaritondo G 2005 Eur. J. Phys. 26 401) to understand the behaviour of a tsunami in a variable depth. We deduce the shallow water wave equation and the continuity equation that must be satisfied when a wave encounters a discontinuity in the sea depth. A short explanation about how the tsunami hit the west coast of India is given based on the refraction phenomenon. Our procedure also includes a simple numerical calculation suitable for undergraduate students in physics and engineering
After the Fukushima Daiichi nuclear power plant (NPP) accident, standard for procedure of tsunami PRA for NPP had been established by the Standardization Committee of AESJ. Industry group had been conducting analysis of Tsunami PRA for PWR based on the standard under the cooperation with electric utilities. This article introduced overview of the standard and examples of accident sequence analysis of Tsunami PRA studied by the industry group according to the standard. The standard consisted of (1) investigation of NPP's composition, characteristics and site information, (2) selection of relevant components for Tsunami PRA and initiating events and identification of accident sequence, (3) evaluation of Tsunami hazards, (4) fragility evaluation of building and components and (5) evaluation of accident sequence. Based on the evaluation, countermeasures for further improvement of safety against Tsunami could be identified by the sensitivity analysis. (T. Tanaka)
Um die unterschiedlichen Ausprägungen von Vulnerabilität der verschiedenen sozialen Gruppen Sri Lankas, die im Dezember 2004 von einem Tsunami überrascht wurden, besser verstehen zu können, wurde eine Befragung von 500 Haushalten im eher städtisch geprägten Distrikt Galle durchgeführt. Koordiniert wurde die Befragung vom Institute of Environment and Human Security der United Nations University (UNU-EHS) in Kooperation mit verschiedenen Instituten. Erklärtes Ziel dieses Projektes ist e...
Grote, Ulrike; Engel, Stefanie; Schraven, Benjamin
The accident which was caused by a tsunami and the Great East-Japan earthquake in 2011 occurred at the Fukushima Nuclear Power Plant (NPP) site. It is obvious that the NPP accident could be incurred by the tsunami. Therefore a Probabilistic Tsunami Hazard Analysis (PTHA) for an NPP site should be required in Korea. The PTHA methodology is developed on the PSHA (Probabilistic Seismic Hazard Analysis) method which is performed by using various tsunami sources and their weights. In this study, the fault sources of northwestern part of Japan were used to analyze as the tsunami sources. These fault sources were suggested by the Atomic Energy Society of Japan (AESJ). To perform the PTHA, the calculations of maximum and minimum wave elevations from the result of tsunami simulations are required. Thus, in this study, tsunami wave propagation analysis were performed for developing the future study of the PTHA.
Rhee, Hyun Me; Kim, Min Kyu; Sheen, Dong Hoon; Choi, In Kil [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
The accident which was caused by a tsunami and the Great East-Japan earthquake in 2011 occurred at the Fukushima Nuclear Power Plant (NPP) site. It is obvious that the NPP accident could be incurred by the tsunami. Therefore a Probabilistic Tsunami Hazard Analysis (PTHA) for an NPP site should be required in Korea. The PTHA methodology is developed on the PSHA (Probabilistic Seismic Hazard Analysis) method which is performed by using various tsunami sources and their weights. In this study, the fault sources of northwestern part of Japan were used to analyze as the tsunami sources. These fault sources were suggested by the Atomic Energy Society of Japan (AESJ). To perform the PTHA, the calculations of maximum and minimum wave elevations from the result of tsunami simulations are required. Thus, in this study, tsunami wave propagation analysis were performed for developing the future study of the PTHA
Eastern Sicily is among the most exposed regions in Italy and in the whole Mediterranean to tsunami hazard and risk. The historical tsunamis recorded here were generally associated to moderate-to-large magnitude earthquakes. The largest tsunami documented in the area occurred on January 11th, 1693. It followed the highest-magnitude earthquake (7.4) of the Italian seismic history. The tsunami, whose first significant motion was a retreat along the entire eastern Sicily coastline, produced the most devastating effects at Augusta (15 meters run-up) and Catania, being relevant at Siracusa and Messina too. A lively debate exists on whether the earthquake was the only source of the tsunami, or other causes (such as submarine landslides, possibly triggered by the earthquake) contributed to the tsunami generation. In the framework of the EC funded project TRANSFER, we investigate both hypotheses, starting from suitable onshore and offshore faults as well as from offshore landslide bodies, and hence simulating numerically the ensuing tsunami and comparing the results with the available historical information. We base on the results obtained during recent offshore surveys, in particular the multichannel seismic survey MESC2001, carried out in year 2001 on board the R/V Urania of the Italian National Council of Researches (CNR), which mapped both active normal faults and a number of possible landslide bodies along the Hyblaean-Malta escarpment, the most prominent tectonic structure found just few kilometres offshore eastern Sicily. From the modelling point of view, the initial condition for the earthquake- generated tsunamis coincides with the vertical coseismic deformation of the seafloor. Instead, the landslide motion is simulated through the Lagrangian block model UBO-BLOCK2, developed at the University of Bologna. Finally, the finite-element code UBO-TSUFE, implemented by the same research team, is used to simulate the tsunami generation and propagation. The main conclusions are: 1) if the earthquake is postulated to be the only responsible for the tsunami, then the historical information can be reproduced only by assuming an offshore tectonic source; 2) taking into account the largest of the mapped landslides, we are able to reproduce quite satisfactorily both the first polarity and the size distribution of the tsunami; 3) we cannot rule out the idea that there was a concurrent contribution of the earthquake and of the landslide in generating the tsunami.
Armigliato, A.; Tinti, S.; Zaniboni, F.; Pagnoni, G.; Argnani, A.
We conduct a detailed seismological study of the large Colima, Mexico earthquake of 1932 June 3 and of its aftershocks of June 18 and 22. The latter (Event III) generated a tsunami more devastating than that of the main shock despite much smaller seismic magnitudes, thus qualifying as a so-called 'tsunami earthquake'. Relocation based on published arrival times shows that Event III took place up-dip of the main shock. The analysis of the spectral amplitude of mantle surface waves yields low-frequency moments of 24, 5.2 and 4 times 1027 dyn cm, respectively, with Event III featuring a moment growing with period, which expresses the source slowness characteristic of 'tsunami earthquakes'. This is confirmed by a deficient energy-to-moment ratio, as derived from high-frequency P waves recorded at Pasadena. Near-field hydrodynamic simulations show that the effects of the main shock's tsunami are well modelled by a standard seismic source, whereas the stronger tsunami from Event III can be modelled by rupture along a splay fault in a mechanically deficient material. All our results then fit the model for 'tsunami earthquake' aftershocks proposed for the Kuril Islands by Fukao in 1979.
Okal, Emile A.; Borrero, José C.
We investigate the currents produced by recent tsunamis in Humboldt Bay and Crescent City, California. The region is susceptible to both near-field and far-field tsunamis and has a historic record of damaging events. Crescent City Harbor, located approximately 100 kms north of Humboldt Bay, suffered US 28 million in damages from strong currents produced by the 2006 Kuril Islands tsunami and an additional US 26 million from the 2011 Japan tsunami. In order to better evaluate these currents in northern California, we deployed a Nortek Aquadopp 600 kHz 2D acoustic Doppler current profiler (ADCP) with a 1-min sampling interval in Humboldt Bay, near the existing National Oceanic and Atmospheric Administration (NOAA) National Ocean Service (NOS) tide gauge station. The instrument recorded the tsunamis produced by the Mw 8.8 Chile earthquake on February 27, 2010 and the Mw 9.0 Japan earthquake on March 11, 2011. One other tsunami was recorded on the Humboldt Bay tide gauge during the period of ADCP operation, but was not visible on the ADCP, suggesting a threshold water level value of about 0.2 m to produce an observable ADCP record. The 2010 tsunami currents persisted in Humboldt Bay for approximately 30 h with peak amplitudes of about 0.35 m/s. The 2011 tsunami signal lasted for over 40 h with peak amplitude of 0.84 m/s. The strongest currents corresponded to the maximum change in water level approximately 67 min after the initial wave arrival. No damage was observed in Humboldt Bay for either event. In Crescent City, currents for the first three and one-half hours of the 2011 Japan tsunami were estimated using security camera video footage from the Harbor Master, approximately 70 m away from the NOAA-NOS tide gauge station. The largest amplitude tide gauge water-level oscillations and most of the damage occurred within this time window. The currents reached a velocity of approximately 4.5 m/s and six cycles exceeded 3 m/s during this period. Measured current velocities both in Humboldt Bay and in Crescent City were compared to calculated velocities from the Method of Splitting Tsunamis (MOST) numerical model. The frequency and pattern of current amplification and decay at both locations are replicated by the MOST model for the first several hours after the tsunami onset. MOST generally underestimates 2011 peak current velocities by about 10-30 %, with a few peaks by as much as 50 %. At Humboldt Bay, MOST predicted attenuation of the signal after 4 h but the actual signal persisted at a nearly constant level for at least twice as long. The results from this project demonstrate that ADCPs can effectively record tsunami currents for small to moderate events and can be used to calibrate and validate models (i.e., MOST) in order to better understand hazardous tsunami conditions within harbors.
Admire, Amanda R.; Dengler, Lori A.; Crawford, Gregory B.; Uslu, Burak U.; Borrero, Jose C.; Greer, S. Dougal; Wilson, Rick I.
HySEA: An operational GPU-based model for Tsunami Early Warning Systems HySEA numerical model for the simulation of earthquake generated tsunamis is presented. The initial sea surface deformation is computed using Okada model. Wave propagation is computed using nonlinear shallow water equations in spherical coordinates, where coastal inundation and run-up are suitable treated in the numerical algorithm. Generation, propagation and inundation phases are all integrated in a single code and computed coupled and synchronously when they occur at the same time. Inundation is modelled by allowing cells to dynamically change from dry to wet and reciprocally when water retreats from wetted areas. Special effort is made in preserving model well-balanced (i.e. capturing small perturbations to the steady state of the ocean at rest). The GPU model implementation allows faster than real time (FTRT) simulation for real large-scale problems. The large speed-ups obtained make HySEA code suitable for its use in Tsunami Early Warning Systems. The Italian TEWS at INGV (Rome) has adopted HySEA GPU code for its National System. The model is verified by hindcasting the wave behaviour in several benchmark problems. Numerical results for an earthquake-generated tsunami in the Mediterranean Sea is presented and computing time analysed. The interest of using higher order methods, analysing numerical schemes from first order up to order five, in the context of TEWS, is also addressed. Tsunami codes do not usually use higher than second order methods. It is demonstrated that this should idea should be revised.
Macias, Jorge; Castro, Manuel J.; González-Vida, José Manuel; de la Asunción, Marc; Ortega, Sergio
Outreach and education save lives, and the Pacific Tsunami Warning Center (PTWC) has a new tool--a YouTube Channel--to advance its mission to protect lives and property from dangerous tsunamis. Such outreach and education is critical for coastal populations nearest an earthquake since they may not get an official warning before a tsunami reaches them and will need to know what to do when they feel strong shaking. Those who live far enough away to receive useful official warnings and react to them, however, can also benefit from PTWC's education and outreach efforts. They can better understand a tsunami warning message when they receive one, can better understand the danger facing them, and can better anticipate how events will unfold while the warning is in effect. The same holds true for emergency managers, who have the authority to evacuate the public they serve, and for the news media, critical partners in disseminating tsunami hazard information. PTWC's YouTube channel supplements its formal outreach and education efforts by making its computer animations available 24/7 to anyone with an Internet connection. Though the YouTube channel is only a month old (as of August 2013), it should rapidly develop a large global audience since similar videos on PTWC's Facebook page have reached over 70,000 viewers during organized media events, while PTWC's official web page has received tens of millions of hits during damaging tsunamis. These animations are not mere cartoons but use scientific data and calculations to render graphical depictions of real-world phenomena as accurately as possible. This practice holds true whether the animation is a simple comparison of historic earthquake magnitudes or a complex simulation cycling through thousands of high-resolution data grids to render tsunami waves propagating across an entire ocean basin. PTWC's animations fall into two broad categories. The first group illustrates concepts about seismology and how it is critical to tsunami warning operations, such as those about earthquake magnitudes, how earthquakes are located, where and how often earthquakes occur, and fault rupture length. The second group uses the PTWC-developed tsunami forecast model, RIFT (Wang et al., 2012), to show how various historic tsunamis propagated through the world's oceans. These animations illustrate important concepts about tsunami behavior such as their speed, how they bend around and bounce off of seafloor features, how their wave heights vary from place to place and in time, and how their behavior is strongly influenced by the type of earthquake that generated them. PTWC's YouTube channel also includes an animation that simulates both seismic and tsunami phenomena together as they occurred for the 2011 Japan tsunami including actual sea-level measurements and proper timing for tsunami alert status, thus serving as a video 'time line' for that event and showing the time scales involved in tsunami warning operations. Finally, PTWC's scientists can use their YouTube channel to communicate with their colleagues in the research community by supplementing their peer-reviewed papers with video 'figures' (e.g., Wang et al., 2012).
Becker, N. C.; Wang, D.; Shiro, B.; Ward, B.
Qualitative research creates mountains of words. U.S. federal funding supports mostly structured qualitative research, which is designed to test hypotheses using semi-quantitative coding and analysis. The authors have 30 years of experience in designing and completing major qualitative research projects, mainly funded by the US National Institute on Drug Abuse [NIDA]. This article reports on strategies for planning, organizing, collecting, managing, storing, retrieving, analyzing, and writing...
Johnson, Bruce D.; Dunlap, Eloise; Benoit, Ellen
On March 11, 2011 at 5:46:23 UTC (March 10 11:46:23 PM Galapagos Local Time), the Mw 9.0 Great East Japan Earthquake occurred near the Tohoku region off the east coast of Japan, spawning a Pacific-wide tsunami. Approximately 12,000 km away, the Galapagos Islands experienced moderate tsunami impacts, including flooding, structural damage, and strong currents. In this paper, we present observations and measurements of the tsunami effects in the Galapagos, focusing on the four largest islands in the archipelago; (from west to east) Isabela, Santiagio, Santa Cruz, and San Cristobal. Access to the tsunami affected areas was one of the largest challenges of the field survey. Aside from approximately ten sandy beaches open to tourists, all other shoreline locations are restricted to anyone without a research permit; open cooperation with the Galapagos National Park provided the survey team complete access to the Islands coastlines. Survey locations were guided by numerical simulations of the tsunami performed prior to the field work. This numerical guidance accurately predicted the regions of highest impact, as well as regions of relatively low impact. Tide-corrected maximum tsunami heights were generally in the range of 3-4 m with the highest runup of 6 m measured in a small pocket beach on Isla Isabela. Puerto Ayora, on Santa Cruz Island, the largest harbor in the Galapagos experienced significant flooding and damage to structures located at the shoreline. A current meter moored inside the harbor recorded relatively weak tsunami currents of less than 0.3 m/s (0.6 knot) during the event. Comparisons with detailed numerical simulations suggest that these low current speed observations are most likely the result of data averaging at 20-min intervals and that maximum instantaneous current speeds were considerably larger. Currents in the Canal de Itabaca, a natural waterway between Santa Cruz Island and a smaller island offshore, were strong enough to displace multiple 5.5-ton navigation buoys. Numerical simulations indicate that currents in the Canal de Itabaca exceeded 4 m/s (~8 knots), a very large flow speed for a navigational waterway.
Lynett, Patrick; Weiss, Robert; Renteria, Willington; De La Torre Morales, Giorgio; Son, Sangyoung; Arcos, Maria Elizabeth Martin; MacInnes, Breanyn Tiel
Highlights: ? A methodology of tsunami PSA was developed in this study. ? Tsunami return period was evaluated by empirical method using historical tsunami record and tidal gauge record. ? Procedure of tsunami fragility analysis was established and target equipments and structures for investigation of tsunami fragility assessment were selected. ? A sample fragility calculation was performed for the equipment in Nuclear Power Plant. ? Accident sequence of tsunami event is developed by according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. - Abstract: A methodology of tsunami PSA was developed in this study. A tsunami PSA consists of tsunami hazard analysis, tsunami fragility analysis and system analysis. In the case of tsunami hazard analysis, evaluation of tsunami return period is a major task. For the evaluation of tsunami return period, numerical analysis and empirical method can be applied. In this study, tsunami return period was evaluated by empirical method using historical tsunami record and tidal gauge record. For the performing a tsunami fragility analysis, procedure of tsunami fragility analysis was established and target equipments and structures for investigation of tsunami fragility assessment were selected. A sample fragility calculation was performed for the equipment in Nuclear Power Plant. In the case of system analysis, accident sequence of tsunami event is developed by according to the s developed by according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. For the application to the real Nuclear Power Plant, the Ulchin 56 NPP which located in east coast of Korean peninsula was selected. Through this study, whole tsunami PSA working procedure was established and example calculation was performed for one of real Nuclear Power Plant in Korea. But for more accurate tsunami PSA result, there are many researches needed for evaluation of hydrodynamic force, effect of debris, structural failure probability of break water structure and intake structure, functional failure criteria for offsite power.
This paper deals with the application of r-solution method to recover the initial tsunami waveform in a tsunami source area by remote water-level measurements. Wave propagation is considered within the scope of a linear shallow-water theory. An ill-posed inverse problem is regularized by means of least square inversion using a truncated SVD approach. The properties of obtained solution are determined to a large extent by the properties of an inverse operator, which were numerically investigated. The method presented allows one to control instability of the numerical solution and to obtain an acceptable result in spite of ill-posedness of the problem. It is shown that the accuracy of tsunami source reconstruction strongly depends on the signal-to-noise ratio, the azimuthal coverage of recording stations with respect to the source area and bathymetric features along the wave path. The numerical experiments were carried out with synthetic data and various computational domains including a real bathymetry. The method proposed allows us to make a preliminary prediction of the efficiency of the inversion with a given set of the recording stations and to find out the most informative part of the existing observation system. This essential property of the method can prove to be useful in designing a monitoring system for tsunamis.
Voronin, V. V.; Voronina, T. A.; Tcheverda, V. A.
The lives of many were changed forever when a tsunami struck on the morning of December 26, 2004, as a result of an earthquake off the coast of Indonesia registering 9.0 on the Richter scale. Aftershocks in the nearby Andaman and Nicobar Islands sent waves of fear among the survivors, further debilitating their spirits. The aim of this article is…
Thirumurthy, Vidya; Uma, V.; Muthuram, R. N.
Full Text Available Catastrophic tsunamis are described in historical sources for all regions around the Gulf of Cadiz, at least since 60 BC. Most of the known events are associated with moderate to large earthquakes and among them the better studied is 1 November 1755. We present here a review of the events which effects, on the coasts of the Portuguese mainland and Madeira Island, are well described in historical documents or have been measured by tide gauges since the installation of these instruments. For a few we include new relevant information for the assessment of the tsunami generation or effects, and we discard events that are included in existing compilations but are not supported by quality historical sources or instrumental records. We quote the most relevant quantitative descriptions of tsunami effects on the Portuguese coast, including in all pertinent cases a critical review of the coeval sources, to establish a homogenous event list. When available, instrumental information is presented. We complement all this information with a summary of the conclusions established by paleo-tsunami research.
M. A. Baptista
Full Text Available This paper deals with the application of r-solution method to recover the initial tsunami waveform in a tsunami source area by remote water-level measurements. Wave propagation is considered within the scope of a linear shallow-water theory. An ill-posed inverse problem is regularized by means of least square inversion using a truncated SVD approach. The properties of obtained solution are determined to a large extent by the properties of an inverse operator, which were numerically investigated. The method presented allows one to control instability of the numerical solution and to obtain an acceptable result in spite of ill-posedness of the problem. It is shown that the accuracy of tsunami source reconstruction strongly depends on the signal-to-noise ratio, the azimuthal coverage of recording stations with respect to the source area and bathymetric features along the wave path. The numerical experiments were carried out with synthetic data and various computational domains including a real bathymetry. The method proposed allows us to make a preliminary prediction of the efficiency of the inversion with a given set of the recording stations and to find out the most informative part of the existing observation system. This essential property of the method can prove to be useful in designing a monitoring system for tsunamis.
V. V. Voronin
"The first 'Workshop Qualitative Research in Psychology' took place in Blaubeuren, Germany from October 20-22, 2000. The meeting was organized by the Center for Qualitative Psychology of the University of Tübingen, Germany. The purpose of the meeting was to begin a network of qualitative psychologists. Thirty-two participants got to know each other, presented and discussed their research, discussed potential further developments within the field of qualitative psychology, and inspired each o...
A very important part of any tsunami early warning system is the numerical simulation of the wave propagation in the open sea and close to geometrically complex coastlines respecting bathymetric variations. Here we are interested in improving the numerical tools available to accurately simulate tsunami wave propagation on a Mediterranean basin scale. To this end, we need to accomplish some targets, such as: high-order numerical simulation in space and time, preserve steady state conditions to avoid spurious oscillations and describe complex geometries due to bathymetry and coastlines. We use the Arbitrary accuracy DERivatives Riemann problem method together with Finite Volume method (ADER-FV) over non-structured triangular meshes. The novelty of this method is the improvement of the ADER-FV scheme, introducing the well-balanced property when geometrical sources are considered for unstructured meshes and arbitrary high-order accuracy. In a previous work from Castro and Toro , the authors mention that ADER-FV schemes approach asymptotically the well-balanced condition, which was true for the test case mentioned in . However, new evidence shows that for real scale problems as the Mediterranean basin, and considering realistic bathymetry as ETOPO-2, this asymptotic behavior is not enough. Under these realistic conditions the standard ADER-FV scheme fails to accurately describe the propagation of gravity waves without being contaminated with spurious oscillations, also known as numerical waves. The main problem here is that at discrete level, i.e. from a numerical point of view, the numerical scheme does not correctly balance the influence of the fluxes and the sources. Numerical schemes that retain this balance are said to satisfy the well-balanced property or the exact C-property. This unbalance reduces, as we refine the spatial discretization or increase the order of the numerical method. However, the computational cost increases considerably this way. Here we show technical details on how to implement a well-balance ADER-FV scheme for the non-linear shallow water equation. Finally, we present numerical simulations of realistic scenarios where unstructured meshes and high-order accuracy are mandatory.  C.E. Castro and E.F. Toro. Solvers for the high-order Riemann problem for hyperbolic balance laws. J.Comput. Phys. 227(4):2481-2513, 2008.  C.E. Castro and M. Käser. Tsunami Simulation with the ADER-DG Numerical Method. 7-12 September 2008, ESC 2008, 31st General Assembly, Creta, Greece.  U.S. Department of Commerce. National oceanic and atmospheric administration, national geophysical data center. 2-minute gridded global relief data (etopo2v2), 2006.
Castro, C. E.; Käser, M.; Toro, E. F.
Although Tsunami events were defined as an external event in 'PRA Procedure Guide (NUREG/CR- 2300)'after 1982, a Tsunami event was not considered in a design and construction of NPP before the Sumatra earthquake in 2004. But the Madras Atomic Power Station, a commercial nuclear power plant owned and operated by the Nuclear Power Corporation of India Limited (NPCIL), and located near Chennai, India, was affected by the tsunami generated by the 2004 Sumatra earthquake (USNRC 2008). The condenser cooling pumps of Unit 2 of the installation were affected due to flooding of the pump house and subsequent submergence of the seawater pumps by tsunami waves. The turbine was tripped and the reactor shut down. The unit was brought to a cold-shutdown state, and the shutdown-cooling systems were reported as operating safely. After this event, Tsunami hazards were considered as one of the major natural disasters which can affect the safety of Nuclear Power Plants. The IAEA performed an Extrabudgetary project for Tsunami Hazard Assessment and finally an International Seismic Safety Center (ISSC) established in IAEA for protection from natural disasters like earthquake, tsunami etc. For this reason, a tsunami hazard assessment method determined in this study. At first, a procedure for tsunami hazard assessment method was established, and second target equipment and structures for investigation of Tsunami Hazard assessment were selected. Finally, a sample fragility calculation was perly, a sample fragility calculation was performed for one of equipment in Nuclear Power Plant
The global catalogue of tsunami events is examined to determine if transient variations in tsunami rates are consistent with a Poisson process commonly assumed for tsunami hazard assessments. The primary data analyzed are tsunamis with maximum sizes >1 m. The record of these tsunamis appears to be complete since approximately 1890. A secondary data set of tsunamis >0.1 m is also analyzed that appears to be complete since approximately 1960. Various kernel density estimates used to determine the rate distribution with time indicate a prominent rate change in global tsunamis during the mid-1990s. Less prominent rate changes occur in the early- and mid-20th century. To determine whether these rate fluctuations are anomalous, the distribution of annual event numbers for the tsunami catalogue is compared to Poisson and negative binomial distributions, the latter of which includes the effects of temporal clustering. Compared to a Poisson distribution, the negative binomial distribution model provides a consistent fit to tsunami event numbers for the >1 m data set, but the Poisson null hypothesis cannot be falsified for the shorter duration >0.1 m data set. Temporal clustering of tsunami sources is also indicated by the distribution of interevent times for both data sets. Tsunami event clusters consist only of two to four events, in contrast to protracted sequences of earthquakes that make up foreshock-main shock-aftershock sequences. From past studies of seismicity, it is likely that there is a physical triggering mechanism responsible for events within the tsunami source 'mini-clusters'. In conclusion, prominent transient rate increases in the occurrence of global tsunamis appear to be caused by temporal grouping of geographically distinct mini-clusters, in addition to the random preferential location of global M >7 earthquakes along offshore fault zones.
Geist, Eric L.; Parsons, Tom
Full Text Available Data on tsunamis occurring in the Black Sea and the Azov Sea from antiquity up to the present were updated, critically evaluated and compiled in the standard format developed since the 90's for the New European Tsunami Catalogue. Twenty nine events were examined but three of them, supposedly occurring in 557 AD, 815 AD and 1341 or 1343, were very likely falsely reported. Most of the remaining 26 events were generated in Crimea, offshore Bulgaria as well as offshore North Anatolia. For each of the 26 events examined, 22 events were classified as reliable ones receiving a score of 3 or 4 on a 4-grade reliability scale. Most of them were caused by earthquakes, such as the key event 544/545 of offshore Varna, but a few others were attributed either to aseismic earth slumps or to unknown causes. The tsunami intensity was estimated using the traditional 6-grade scale and the new 12-grade scale introduced by Papadopoulos and Imamura (2001. From 544/545 up to now, only two reliable events of high intensity K ? 7 have been reported, which very roughly indicates that the mean repeat time is ? 750 years. Five reliable tsunamis of moderate intensity 4 ? K < 7 have been observed from 1650 up to the present, which implies a recurrence of 72 years on the average. Although these calculations were based on a very small statistical sample of tsunami events, the repeat times found are consistent with the theoretical expectations from size-frequency relations. However, in the Black Sea there is no evidence of tsunamis of very high intensity (K ? 10 such as the AD 365, 1303 and 1956 ones associated with large earthquakes occurring along the Hellenic arc and trench, Greece, or the 1908 one in Messina strait, Italy. This observation, along with the relatively low tsunami frequency, indicates that the tsunami hazard in the Black Sea is low to moderate but not negligible. The tsunami hazard in the Azov Sea is very low because of the very low seismicity but also because of the shallow water prevailing there. In fact, only three possible tsunami events have been reported in the Azov Sea.
G. A. Papadopoulos
Since the 1970s, solitary waves have commonly been used to model tsunamis especially in experimental and mathematical studies. Unfortunately, the link to geophysical scales is not well established, and in this work we question the geophysical relevance of this paradigm. In part 1, we simulate the evolution of initial rectangular shaped humps of water propagating large distances over a constant depth. The objective is to clarify under which circumstances the front of the wave can develop into an undular bore with a leading soliton. In this connection we discuss and test various measures for the threshold distance necessary for nonlinear and dispersive effects to manifest in a transient wave train. In part 2, we simulate the shoaling of long smooth transient and periodic waves on a mild slope and conclude that these waves are effectively non-dispersive. In this connection we discuss the relevance of finite amplitude solitary wave theory in laboratory studies of tsunamis. We conclude that order-of-magnitude errors in effective temporal and spatial duration occur when this theory is used as an approximation for long waves on a sloping bottom. In part 3, we investigate the phenomenon of disintegration of long waves into shorter waves, which has been observed e.g. in connection with the Indian Ocean tsunami in 2004. This happens if the front of the tsunami becomes sufficently steep, and as a result the front turns into an undular bore. We discuss the importance of these very short waves in connection with breaking and runup, and conclude that they do not justify a solitary wave model for the bulk tsunami.
Madsen, Per A.; Fuhrman, David R.
Traditional tsunami inundation maps have focused on maximum on-land inundation. Occasionally, the inundation maps are supplemented with information about maximum water velocity or timing. We demonstrate using several case studies the utility of producing maps showing 1) on-land inundation area, 2) maximum water velocity, 3) maximum water flux, 4) time of wave arrival, 5) time of wave maximum, and 6) time of wave departure. Map attributes 1-3 are related to water motion and are of particular value to scientists involved in tsunami hazard assessment. Attributes 4-6 are related to the timing of wave events and are of particular value to emergency managers. However, this raw form of inundation mapping is not easily interpreted within the usual GIS context because water velocities and fluxes are not readily understood by lay people. To improve on the GIS approach to portraying tsunami information, we employ simple engineering models illustrating the consequences of tsunami attack in a way that lay audiences can readily understand. In particular, we present maps that depict regions where a human would be knocked down, where cars would be moved, where various sizes of sediment would be moved, where anchors would break, and where ships would be moved laterally by a significant amount. Each map is separated into three distinct layers, each layer representing a different level of hazard. For example, the car movement map shows results for three sizes of automobile. Each region is depicted as a separate GIS layer. Given the uncertainty involved in numerical simulations, as well as the many local variables that can alter the outcome during a real event, these maps are meant to provide general guidelines as to the outcome of tsunami attack.
Watts, P.; Walder, J. S.; Waythomas, C. F.
Italy is characterized by a great coastal extension, and by a series of possible tsunamigenic sources: many active faults, onshore and offshore, also near the shoreline and in shallow water, active volcanoes (Etna, Stromboli, Campi Flegrei for example), continental margins where landslides can occur. All these threats justify the establishment of a tsunami early warning system (TEWS), especially in Southern Italy where most of the sources capable of large disastrous tsunamis are located. One of the main characteristics of such sources, that however is common to other countries in not only in the Mediterranean, is their vicinity to the coast, which means that the tsunami lead time for attacking the coastal system is expected to be within 10-15 minutes in several cases. This constraint of time imposes to conceive and adopt specific plans aiming at a quick tsunami detection and alert dissemination for the TEWS, since obviously the TEWS alert must precede and not follow the tsunami first arrival. The need to be quick introduces the specific problem of uncertainty that is though inherent to any forecast system, but it is a very big issue especially when time available is short, since crucial decisions have to be taken in presence of incomplete data and incomplete processing. This is just the big problem that has to be faced by a system like the a TEWS in Italy. Uncertainties can be reduced by increasing the capabilities of the tsunami monitoring system by densifying the traditional instrumental networks (e.g. by empowering seismic and especially coastal and offshore sea-level observation systems) in the identified tsunamigenic source areas. However, uncertainties, though are expected to have a decreasing trend as time passes after the tsunami initiation, cannot be eliminated and have to be appropriately dealt with: uncertainties lead to under- and overestimation of the tsunami size and arrival times, and to missing or to false alerts, or in other terms they degrade the performance of the tsunami predictors. The role of the local communities in defining the strategies in case of uncertain data is essential: only involvement of such communities since the beginning of the planning and implementation phase of the TEWS as well as in the definition of a decision making matrix can ensure appropriate response in case of emergency, and most importantly, the acceptance of the system in the long run. The efforts to implement the Tsunami Warning System in Italy should take into proper account the above mentioned aspects. Involvement of local communities should be primarily realized through the involvement of the local components of the Civil Protection Agency that is responsible for the implementation of the system over the Italian territory. A pilot project is being conducted in cooperation between the Civil Protection Service of Sicily and the University of Bologna (UNIBO) that contemplates the empowering of the local sea-level monitoring system (TSUNET) and specific vulnerability and risk analyses, also exploiting results of national and European research projects (e.g. TRANSFER and SCHEMA) where UNIBO had a primary role.
Tinti, Stefano; Armigliato, Alberto; Zaniboni, Filippo
Tsunamis occurred in the past at the North Sea, but not frequently. There are historical and geological records of several tsunamis: the Storegga tsunami caused sediment deposits in Scotland 8,000 years ago and records of at least six earthquake-generated tsunamis exist from 842 to 1761 AC. The highest tsunami height witnessed at the German Bight is comparable to the maximum storm surge recorded and could thus cause similar or higher damage. However, there is little research on tsunami modeli...
Silvia Chacón-Barrantes; Rangaswami Narayanan; Roberto Mayerle
Two devastating tsunamis in the 21st century were caused by large megathrust earthquakes on tectonic plate boundaries; the Boxing Day tsunami in 2004 and the Great Tohoku tsunami in 2011. Both of these events have led to a focus on tsunamis caused by megathrusts when assessing risks to coastal nuclear power plants. From a longer time perspective, however, such earthquakes are not the only - or even the most significant - sources of large tsunamis. It is important that the key lesson from the impact of the Great Tohoku earthquake and associated tsunami on the Fukushima Dai-ichi power plant - that unexpected combinations of events can cause complete failure of defence in depth - is not lost by looking in too much detail at these particular incidents. Instead a wider assessment of events that can give rise to giant waves and major inundation should be considered. (author)
On 27 February 2010, a magnitude M w = 8.8 earthquake occurred off the coast of Chile's Maule region causing substantial damage and loss of life. Ancestral tsunami knowledge from the 1960 event combined with education and evacuation exercises prompted most coastal residents to spontaneously evacuate after the earthquake. Many of the tsunami victims were tourists in coastal campgrounds. The international tsunami survey team (ITST) was deployed within days of the event and surveyed 800 km of coastline from Quintero to Mehuín and the Pacific Islands of Santa María, Mocha, Juan Fernández Archipelago, and Rapa Nui (Easter). The collected survey data include more than 400 tsunami flow depth, runup and coastal uplift measurements. The tsunami peaked with a localized runup of 29 m on a coastal bluff at Constitución. The observed runup distributions exhibit significant variations on local and regional scales. Observations from the 2010 and 1960 Chile tsunamis are compared.
Fritz, Hermann M.; Petroff, Catherine M.; Catalán, Patricio A.; Cienfuegos, Rodrigo; Winckler, Patricio; Kalligeris, Nikos; Weiss, Robert; Barrientos, Sergio E.; Meneses, Gianina; Valderas-Bermejo, Carolina; Ebeling, Carl; Papadopoulos, Athanassios; Contreras, Manuel; Almar, Rafael; Dominguez, Juan Carlos; Synolakis, Costas E.
Numerous tsunamis occurred in the West Mediterranean with magnitudes ranging from m=-1 to m=2 (Imamura-Iida scale). In Algeria, tsunamis are reported from the 14th century to 2003. Northern Algeria is located at the border between the African and the Eurasian plate. Destructive earthquakes with magnitude greater than 6.7 occurred 3 times in the last century. The North Algeria western region is characterized by the Murdjadjo anticline. A destructive earthquake hit Oran city on October 1790 (Intensity: X, West of Algeria). A tsunami was triggered in the Alboran sea. The Spanish and North Africa coasts were flooded. Run-up’s of 2 meters in height are reported in historical documents (Lopez Marinas and Salord, 1990). Here, the 1790 Alboran tsunami is studied from a modelling approach. The tsunami source is determined from the Okada equations and the tsunami propagation is estimated from the SWAN code (Mader, 2004). Results show that active thrust faulting related to the Murdjadjo structure is responsible for the tsunami. In the central part of Algeria, the Algiers city (capital of Algeria) was the location of destructive earthquakes (Intensity: X) that were followed by tsunamis in 1365 and in 1773. Flooding and run-up’s of 2 meters in height are reported in historical documents for the 1365 event. The central part of Algeria is the site of the Sahel anticline. A tsunami modelling is also performed considering the Sahel fault system as a potential tsunami source. Results show that it takes less than 15 minutes for the tsunami waves to reach the Spanish coast. Run-up’s are estimated lower than 2 meters in height. Discrepancies are attributed to the resolution of the bathymetry and the limits of the modelling. In the eastern region, historical reports also reveal run-up’s up to 5 meters in height after a tsunami triggered by a destructive earthquake in 1856 in Jijel city (intensity: VIII). From tsunami catalogs, seismic and tsunami data are plotted using a tsunami vulnerability parameter. The vulnerability index is estimated from the tsunami intensity and the seismic intensity using the Papadopoulos and the EMS scale. Results show that in Algeria, tsunami damages are minor relative to seismic damages. Since the 2004 Sumatra-Andaman tsunami, intergovernmental coordinated groups are working on an Indian and a Mediterranean tsunami alert system. To reduce vulnerability and increase resilience, it is very important to implement an efficiency warning system and a communication policy for fast urbanized coastal cities. In that context, lessons from the pacific case study are of major interest. Chile is marked by a very high seismic and tsunami hazard. The Iquique area is a threaten zone for a potential earthquake of magnitude greater than 8 and a local tsunami that could generate run-up’s up to 20 meters in height. In addition to the Pacific Tsunami Warning centre based in Hawaii, the Chile has elaborated a local tsunami warning centre. The Chilean case study is presented in discussion to highlight some lessons that may serve as an example for fast urbanized coastal cities that have to face local tsunamis.
Amir, L. A.; Cisternas, A.; Vigneresse, J. D.
All available tsunami observations at tide gauges situated along the North American coast were examined to determine if there is any clear relationship between maximum amplitude and signal duration. In total, 89 historical tsunami recordings generated by 13 major earthquakes between 1952 and 2011 were investigated. Tidal variations were filtered out of the signal and the duration between the arrival time and the time at which the signals drops and stays below 0.3 m amplitude was computed. The processed tsunami time series were evaluated and a linear least-squares fit with a 95 % confidence interval was examined to compare tsunami durations with maximum tsunami amplitude in the study region. The confidence interval is roughly 20 h over the range of maximum tsunami amplitudes in which we are interested. This relatively large confidence interval likely results from variations in local resonance effects, late-arriving reflections, and other effects.
Kim, Yoo Yin; Whitmore, Paul M.
Full Text Available The 1918 tsunami that inundated northwest Puerto Rico with up to 6 m waves has been attributed to seafloor faulting associated with the 1918 Mona Canyon earthquake. During the earthquake a series of submarine cable breaks occurred directly off the northwest coast of Puerto Rico where the largest tsunami waves came ashore. Here, we use a recently compiled geophysical data set to reveal that a 9 km long landslide headwall exists in the region where cable breaks occurred during the 1918 earthquake. We incorporate our interpretations into a near-field tsunami wave model to evaluate whether the slide may have triggered the observed 1918 tsunami. Our analysis indicates that this slide could generate a tsunami with phase, arrival times, and run-ups similar to observations along the northwest coast of Puerto Rico. We therefore suggest that a submarine slide offers a plausible alternative explanation for generation of this large tsunami.
Matthew J. Hornbach
Darwin landed at Valdivia and Concepcion, Chile, just before, during, and after a great 1835 earthquake. He described his impressions and results of the earthquake-induced natural catastrophe in The Voyage of the Beagle. His description of the tsunami could easily be read as a report from Indonesia or Sri Lanka, after the catastrophic tsunami of 26 December 2004. In particular, Darwin emphasised the dependence of earthquake-induced waves on a form of the coast and the coastal depth: ‘… Talcuhano and Callao are situated at the head of great shoaling bays, and they have always suffered from this phenomenon; whereas, the town of Valparaiso, which is seated close on the border of a profound ocean... has never been overwhelmed by one of these terrific deluges…' . He reports also, that ‘… the whole body of the sea retires from the coast, and then returns in great waves of overwhelming force ...' (we cite the Darwin's sentences following researchspace. auckland. ac. nz/handle/2292/4474). The coastal evolution of a tsunami was analytically studied in many publications (see, for example, Synolakis, C.E., Bernard, E.N., 2006. Philos. Trans. R. Soc., Ser. A, 364, 2231-2265; Tinti, S., Tonini, R. 205. J.Fluid Mech., 535, 11-21). However, the Darwin's reports and the influence of the coastal depth on the formation and the evolution of the steep front and the profile of tsunami did not practically discuss. Recently, a mathematical theory of these phenomena was presented in researchspace. auckland. ac. nz/handle/2292/4474. The theory describes the waves which are excited due to nonlinear effects within a shallow coastal zone. The tsunami elevation is described by two components: . Here is the linear (prime) component. It describes the wave coming from the deep ocean. is the nonlinear component. This component may become very important near the coastal line. After that the theory of the shallow waves is used. This theory yields the linear equation for and the weakly-nonlinear equation for . The last equation contains the forcing term which is generated by nonlinearity and depends on . The nonlinear shock-like solution for is constructed which is valid within the narrow coastal zone. Then the tsunami evolution near a coast is studied. It is found that the coastal evolution strongly depends on the profile of the bottom and the distance from the coastline. Far from this the wave surface is smooth and the wave is long enough. The wave profile begins to change quickly, if the coastal water is shallow. The steep (discontinuous) front of the tsunami can be generated. The water level reduces ahead of the front, or the ebb can appear there. Then this front begins to move away from the coast - into the ocean. This direction is opposite to the motion of the whole wave. The amplitude of the front is increased. The water wall is formed. This process explains the catastrophic effect of a tsunami, when a water-wall appears instantly. The wave, having two steep peaks, may be generated in the case of very shallow water. In contrast with this, the tsunami, practically, does not change, if the coastal water is deep. On the whole, the conclusions agree with the Darwin's reports.
The Asian tsunami of December 26, 2004 wreaked havoc along the southeastern coast of India and resulted in devastating losses. The high rates of long-term mental health consequences in adult survivors predicted immediately after the disaster have not been borne out by recent surveys. This qualitative study explored the psychological impact of the tsunami on survivors with a view to gaining insights into the ethno-cultural coping mechanisms of affected communities and evaluating resilience in the face of incomprehensible adversity. We conducted focus group discussions 9 months after the tsunami with two groups of fishermen, two groups of housewives, a group of village leaders and a group of young men in four affected villages of Nagapattinam district in Tamil Nadu, India. In spite of incomplete reconstruction of their lives, participants reconstructed meaning for the causes and the aftermath of the disaster in their cultural idiom. Qualitative changes in their social structure, processes and attitudes towards different aspects of life were revealed. Survivors valued their unique individual, social and spiritual coping strategies more than formal mental health services. Their stories confirm the assertion that the collective response to massive trauma need not necessarily result in social collapse but also includes positive effects. The results of this study suggest that interventions after disaster should be grounded in ethno-cultural beliefs and practices and should be aimed at strengthening prevailing community coping strategies.
Rajamani, Anto Praveen Rajkumar; Premkumar, Titus S
Risk and vulnerability assessment is an important component of an effective End-to-End Tsunami Early Warning System and therefore contributes significantly to disaster risk reduction. Risk assessment is a key strategy to implement and design adequate disaster prevention and mitigation measures. The knowledge about expected tsunami hazard impacts, exposed elements, their susceptibility, coping and adaptation mechanisms is a precondition for the development of people-centred warning structures, local specific response and recovery policy planning. The developed risk assessment and its components reflect the disaster management cycle (disaster time line) and cover the early warning as well as the emergency response phase. Consequently the components hazard assessment, exposure (e.g. how many people/ critical facilities are affected?), susceptibility (e.g. are the people able to receive a tsunami warning?), coping capacity (are the people able to evacuate in time?) and recovery (are the people able to restore their livelihoods?) are addressed and quantified. Thereby the risk assessment encompasses three steps: (i) identifying the nature, location, intensity and probability of potential tsunami threats (hazard assessment); (ii) determining the existence and degree of exposure and susceptibility to those threats; and (iii) identifying the coping capacities and resources available to address or manage these threats. The paper presents results of the research work, which is conducted in the framework of the GITEWS project and the Joint Indonesian-German Working Group on Risk Modelling and Vulnerability Assessment. The assessment methodology applied follows a people-centred approach to deliver relevant risk and vulnerability information for the purposes of early warning and disaster management. The analyses are considering the entire coastal areas of Sumatra, Java and Bali facing the Sunda trench. Selected results and products like risk maps, guidelines, decision support information and other GIS products will be presented. The focus of the products is on the one hand to provide relevant risk assessment products as decision support to issue a tsunami warning within the early warning stage. On the other hand the maps and GIS products shall provide relevant information to enable local decision makers to act adequately concerning their local risks. It is shown that effective prevention and mitigation measures can be designed based on risk assessment results and information especially when used pro-active and beforehand a disaster strikes. The conducted hazard assessment provides the probability of an area to be affected by a tsunami threat divided into two ranked impact zones. The two divided impact zones directly relate to tsunami warning levels issued by the Early Warning Center and consequently enable the local decision maker to base their planning (e.g. evacuation) accordingly. Within the tsunami hazard assessment several hundred pre-computed tsunami scenarios are analysed. This is combined with statistical analysis of historical event data. Probabilities of tsunami occurrence considering probabilities of different earthquake magnitudes, occurrences of specific wave heights at coast and spatial inundation probability are computed. Hazard assessment is then combined with a comprehensive vulnerability assessment. Here deficits in e.g. people's ability to receive and understand a tsunami warning and deficits in their ability to respond adequately (evacuate on time) are quantified and are visualized for the respective coastal areas. Hereby socio-economic properties (determining peoples ability to understand a warning and to react) are combined with environmental conditions (land cover, slope, population density) to calculate the time needed to evacuate (reach a tsunami safe area derived through the hazard assessment). This is implemented using a newly developed GIS cost-distance weighting approach. For example, the amount of people affected in a certain area is dependent on expected tsunami intensity, inundated area, estimated tsuna
Post, J.; Zosseder, K.; Wegscheider, S.; Steinmetz, T.; Mück, M.; Strunz, G.; Riedlinger, T.; Anwar, H. Z.; Birkmann, J.; Gebert, N.
We present the results of a numerical modeling study investigating the effects of far-field tsunamis in New Zealand ports. Four sites (Marsden Point, Tauranga, Harbor, Port Taranaki and Lyttelton Harbor) were selected based on a combination of factors such as economic importance and the availability of historical and/or instrumental data. Numerical models were created using the ComMIT tsunami modeling tool and the Method Of Splitting Tsunami (MOST) hydrodynamic model. Comparison of model results to measured data from recent historical events showed that, for particular sites and events, the model correlated well with the timing and amplitude of the observed tsunami, and, in most cases, there was generally good agreement between the and modeled tsunami heights and current speeds. A sensitivity analysis for tsunami heights and current speeds was conducted using a suite of large (M W 9) tsunamigenic earthquake sources situated at regular 15° intervals in azimuth along the Pacific Rim while another set of scenarios focused on regional tsunami sources in the Southwest Pacific. Model results were analyzed for tsunami heights and current speeds as a function of the source region. In terms of currents, the analysis identified where speeds were greatest and which source was responsible. Results suggested that tsunamis originating from Central America produced the strongest response in New Zealand. The modeling was also used to determine the timing and duration of potentially dangerous current speeds as well as minimum `safe depths' for vessel evacuation offshore. This study was motivated by the desire to reduce damage and operational losses via improved forecasting of far-field tsunamis at New Zealand ports. It is important that forecasts are accurate since tsunami damage to ships and facilities is expensive and can be mitigated given timely warnings and because preventable false alarms are also costly in terms of lost productivity. The modeling presented here will underpin efforts to produce port-specific guidance and information in the event of future Pacific tsunamis.
Borrero, Jose C.; Goring, Derek G.; Greer, S. Dougal; Power, William L.
The aim of this investigation is to understand the geochemical variation in east coast of marine environment near existing and proposed DAE facilities due to Tsunami. Hence interest in the post Tsunami Environmental Impact study is on the concentration and distribution of radioelement and associated heavy metals. It is therefore essential to study the impact of Tsunami on the marine ecosystem which has been subject to to the impact of industrialization and urbanization of land
Many studies have modeled the Tohoku tsunami of March 11, 2011 as being due entirely to slip on an earthquake fault, but the following discrepancies suggest that further research is warranted. (1) Published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40 m measured along the coast of the Sanriku district in the northeast part of Honshu Island. (2) Published models cannot reproduce the timing and high-frequency content of tsunami waves recor...
Tappin, David R.; Grilli, Stephan T.; Harris, Jeffrey C.; Geller, Robert J.; Masterlark, Timothy; Kirby, James T.; Shi, Fengyan; Ma, Gangfeng; Thingbaijam, K. K. S.; Mai, P. Martin
Probabilistic hazard assessments are a fundamental tool for assessing the threats posed by hazards to communities and are important for underpinning evidence based decision making on risk mitigation activities. Indonesia has been the focus of intense tsunami risk mitigation efforts following the 2004 Indian Ocean Tsunami, but this has been largely concentrated on the Sunda Arc, with little attention to other tsunami prone areas of the country such as eastern...
Horspool, N.; Pranantyo, I.; Griffin, J.; Latief, H.; Natawidjaja, D. H.; Kongko, W.; Cipta, A.; Bustaman, B.; Anugrah, S. D.; Thio, H. K.
#Tsunami, one of the most horrible disasters in the earth, the killer wave contains incogitable powerful energy rushing to the shore and coastline. Nowadays the best way for avoiding the tragedy is to use Tsunami Warning System (TWS) to forecast. How does it work? Does it could be reliable enough? These questions attract us to find answer and make discovery. Before understanding the truth of TWS, the first important knowledge that can not be missed is Plate tectonic. Because most of tsunamis ...
Lei, Hong; Yang, Liu; Ru, Liu; Jing Jing, Liu; Shen Yuan, Wang; Hui, Zhao; Kang Min, Wu
Fostered by and embedded in the general development of information and communications technology (ICT), the evolution of tsunami warning systems (TWS) shows a significant development from seismic-centred to multi-sensor system architectures using additional sensors (e.g. tide gauges and buoys) for the detection of tsunami waves in the ocean.
Currently, the beginning implementation of regional tsunami warning infrastructures indicates a new phase in the development of TWS....
Wa?chter, J.; Babeyko, A.; Fleischer, J.; Ha?ner, R.; Hammitzsch, M.; Kloth, A.; Lendholt, M.
In 2006, the UK Department for Food and Rural affairs (DEFRA) commissioned the British Geological Survey (BGS) to establish a system capable of detecting and discriminating earthquakes which could pose a tsunami risk to the UK. Previous studies for DEFRA had shown that the UK risk from tsunamis is low, but not negligible. The system must be able to become part of an integrated tsunami warning process, if one is implemented in the future. Rather than start from scratch in developing suitabl...
Luckett, Richard; Ottemoller, Lars; Whitmore, Paul
The Algerian coastline is located at the border between the African and the Eurasian tectonic plates. The collision between these two plates is approximately 4 to 7 mm/yr. The Alps and the tellian Atlas result from this convergence. Historical and present day data show the occurrence of earthquakes with magnitude up to 7 degrees on Richter scale in the northern part of the country. Cities were destroyed and the number of victims reached millions of people. Recently, small seismic waves generated by a destructive earthquake (Epicenter: 36.90N, 3.71E; Mw=6.8; Algeria, 2003, NEIC) were recorded in the French and Spanish coasts. This event raised again the issue of tsunami hazard in western Mediterranean region. For the Algerian study case, the assessment of seismic and tsunami hazard is a matter of great interest because of fast urban development of cities like Algiers. This study aims to provide scientific arguments to help in the elaboration of the Mediterranean tsunami alert program. This is a real complex issue because (1) the western part of the sea is narrow, (2) constructions on the Algerian coastline do not respect safety standards and (3) the seismic hazard is important. The present work is based on a numerical modeling approach. Firstly, a database is created to gather and list information related to seismology, tectonic, abnormal sea level's variations recorded/observed, submarine and coastal topographic data for the western part of the Mediterranean margin. This database helped to propose series of scenario that could trigger tsunami in the Mediterranean sea. Seismic moment, rake and focal depth are the major parameters that constrain the modeling input seismic data. Then, the undersea earthquakes modeling and the seabed deformations are computed with a program adapted from the rngchn code based on Okada's analytic equations. The last task of this work consisted to calculate the initial water surface displacement and simulate the triggered tsunami. Generation and propagation of induced seismic waves were estimated with another program adapted from the swan code for the resolution of the hydrodynamic shallow water equations. The results obtained will be firstly presented. Then, based on seismic waves travel times and run up height values, a large discussion will focus on the tsunami alert program for cities marked by fast urban development.
Amir, L. A.
The ability to measure, predict, and compute tsunami flow velocities is of importance in risk assessment and hazard mitigation. Substantial damage can be done by high velocity flows, particularly in harbors and bays, even when the wave height is small. Moreover, advancing the study of sediment transport and tsunami deposits depends on the accurate interpretation and modeling of tsunami flow velocities and accelerations. Until recently, few direct measurements of tsunami velocities existed to compare with model results. During the 11 March 2011 Tohoku Tsunami 328 current meters were in place around the Hawaiian Islands, USA, that captured time series of water velocity in 18 locations, in both harbors and deep channels, at a series of depths. We compare several of these velocity records against numerical simulations performed using the GeoClaw numerical tsunami model, based on solving the depth-averaged shallow water equations with adaptive mesh refinement, to confirm that this model can accurately predict velo...
Arcos, M E M
We investigated the correlation between coastal and offshore tsunami heights by using data from the Dense Oceanfloor Network for Earthquakes and Tsunamis (DONET) observational array of ocean-bottom pressure gauges in the Nankai trough off the Kii Peninsula, Japan. For near-field earthquakes, hydrostatic pressure changes may not accurately indicate sea surface fluctuations, because ocean-bottom pressure gauges are simultaneously displaced by crustal deformation due to faulting. To avoid this problem, we focused on the average waveform of the absolute value of the hydrostatic pressure changes recorded at all the DONET stations during a tsunami. We conducted a Monte Carlo tsunami simulation that revealed a clear relationship between the average waveforms of DONET and tsunami heights at the coast. This result indicates the possibility of accurate real-time prediction of tsunamis by use of arrays of ocean-bottom pressure gauges.
Baba, Toshitaka; Takahashi, Narumi; Kaneda, Yoshiyuki
Full Text Available Most coastal locations have few if any records of tsunami wave heights obtained over various time periods. Still one sees reference to the 100- year and 500-year tsunamis. In fact, in the USA, FEMA requires that at all coastal regions, those wave heights due to tsunamis and hurricanes be specified. The same is required for stream flooding at any location where stream flooding is possible. How are the 100 and 500-year tsunami wave and stream flooding heights predicted and how defensible are they? This paper discusses these questions.
Harold G. Loomis
A massive earthquake with a magnitude of 9.0 occurred on March 11, 2011, and a powerful tsunami devastated a large area along Japan???s eastern coastline. We investigated the tsunami damage using satellite images and aerial photographs, and visited damaged sites including 27 shrines near the coast in 2011 and 2012. It was found that all but two of these shrines survived the tsunami, even though the tsunami height differed from place to place. As a memorial to people who lost their lives in pr...
Sakai, K.; Uda, T.; Nami, T. S.
The Arabian Peninsula has been affected by tsunamis in the past. The Peninsula is bounded by the Persian Gulf on its northeast side, the Red Sea on its west side, and the Arabian Sea, the Gulf of Aden, and the Indian Ocean to its east and south. Each of these areas is very different geographically, tectonically, and bathymetrically.Only two, localized tsunamis have been recorded in the Red Sea and one, doubtful, tsunami in the Persian Gulf. Almost all of the recorded tsunamis along the Arabia...
Jordan, Benjamin R.
Full Text Available On Boxing Day 2004, a severe tsunami was generated by a strong earthquake in Northern Sumatra causing a large number of casualties. At this time, neither an offshore buoy network was in place to measure tsunami waves, nor a system to disseminate tsunami warnings to local governmental entities. Since then, buoys have been developed by Indonesia and Germany, complemented by NOAA's Deep-ocean Assessment and Reporting of Tsunamis (DART buoys, and have been moored offshore Sumatra and Java. The suite of sensors for offshore tsunami detection in Indonesia has been advanced by adding GPS technology for water level measurements.
The usage of GPS buoys in tsunami warning systems is a relatively new approach. The concept of the German Indonesian Tsunami Early Warning System (GITEWS (Rudloff et al., 2009 combines GPS technology and ocean bottom pressure (OBP measurements. Especially for near-field installations where the seismic noise may deteriorate the OBP data, GPS-derived sea level heights provide additional information.
The GPS buoy technology is precise enough to detect medium to large tsunamis of amplitudes larger than 10 cm. The analysis presented here suggests that for about 68% of the time, tsunamis larger than 5 cm may be detectable.
A catalog of about ninety tsunamis in the Indian Ocean has been prepared from 326 BC to 2005 AD. In the nineteenth and twentieth centuries tsunamis have occurred once in three years or so. Sunda Arc is the most active region that has produced about seventy tsunamis. The source zones of the remaining tsunamis are Andaman-Nicobar islands, Burma-Bangladesh region in the eastern side, while Makran accretion zone and Kutch- Saurashtra region are in the west. These zones are subduction zones or zon...
Rastogi, B. K.; Jaiswal, R. K.
Full Text Available Tsunami propagation is analyzed for the Ligurian Sea with particular attention on the French coasts of the Mediterranean. Historical data of tsunami manifestation on the French coast are analyzed for the period 2000 B.C.–1991 A.D. Numerical simulations of potential and historical tsunamis in the Ligurian Sea are done in the context of the nonlinear shallow water theory. Tsunami wave heights as well as their distribution function is calculated for historical tsunamis and it is shown that the log-normal distribution describes reasonably the simulated data. This demonstrates the particular role of bottom irregularities for the wave height distribution function near the coastlines. Also, spectral analysis of numerical tide-gauge records is done for potential tsunamis, revealing the complex resonant interactions between the tsunami waves and the bottom oscillations. It is shown that for an earthquake magnitude of 6.8 (averaged value for the Mediterranean Sea the tsunami phenomenon has a very local character but with long duration. For sources located near the steep continental slope in the vicinity of the French-Italian Rivera, the tsunami tide-gauge records in the vicinity of Cannes – Imperia present irregular oscillations with a characteristic period of 20–30 min and a total duration of 10–20 h. For the western French coasts the amplitudes are significantly less with characteristic low-frequency oscillations (period of 40 min–1 h.
Most coastal locations have few if any records of tsunami wave heights obtained over various time periods. Still one sees reference to the 100- year and 500-year tsunamis. In fact, in the USA, FEMA requires that at all coastal regions, those wave heights due to tsunamis and hurricanes be specified. The same is required for stream flooding at any location where stream flooding is possible. How are the 100 and 500-year tsunami wave and stream flooding heights predicted and how defensible are th...
Loomis, Harold G.
Full Text Available A catalog of about ninety tsunamis in the Indian Ocean has been prepared from 326 BC to 2005 AD. In the nineteenth and twentieth centuries tsunamis have occurred once in three years or so. Sunda Arc is the most active region that has produced about seventy tsunamis. The source zones of the remaining tsunamis are Andaman-Nicobar islands, Burma-Bangladesh region in the eastern side, while Makran accretion zone and Kutch- Saurashtra region are in the west. These zones are subduction zones or zones of compression.
B. K. Rastogi
Full Text Available The importance of tsunami hazard assessment has increased in recent years as a result of catastrophic consequences from events such as the 2004 Indian Ocean and 2011 Japan tsunamis. In particular, probabilistic tsunami hazard assessment (PTHA methods have been emphasized to include all possible ways a tsunami could be generated. Owing to the scarcity of tsunami observations, a computational approach is used to define the hazard. This approach includes all relevant sources that may cause a tsunami to impact a site and all quantifiable uncertainty. Although only earthquakes were initially considered for PTHA, recent efforts have also attempted to include landslide tsunami sources. Including these sources into PTHA is considerably more difficult because of a general lack of information on relating landslide area and volume to mean return period. The large variety of failure types and rheologies associated with submarine landslides translates to considerable uncertainty in determining the efficiency of tsunami generation. Resolution of these and several other outstanding problems are described that will further advance PTHA methodologies leading to a more accurate understanding of tsunami hazard.
Eric L. Geist
On March 11th, 2011, a tremendous earthquake and tsunami occurred on the east coast of Japan. This 9.0 magnitude earthquake was the fifth greatest earthquake ever experienced on the planet. The most remarkable problem was that the Fukushima NPP sites, including their cores, were damaged. The term 'core damage' can be found in safety reports or textbooks on nuclear engineering. Therefore, in this study, a tsunami hazard assessment was performed for Korean NPP sites and was compared to a Japanese tsunami hazard assessment based on a previous tsunami PSA study
The main goal of this study is to give the preliminary estimates of the tsunami risks for the Lesser Antilles. We investigated the available data of the tsunamis in the French West Indies using the historical data and catalogue of the tsunamis in the Lesser Antilles. In total, twenty-four (24) tsunamis were recorded in this area for last 400 years; sixteen (16) events of the seismic origin, five (5) events of volcanic origin and three (3) events of unknown source. Most of the tsunamige...
Zahibo, N.; Pelinovsky, E. N.
After the 2004 Indian Ocean tsunami catastrophe, UNESCO through the IOC (Intergovernmental Oceanographic Commission) sponsored the establishment of Intergovernmental Coordination Groups (ICG) with the aim to devise and implement Tsunami Warning Systems (TWSs) in all the oceans exposed to tsunamis, in addition to the one already in operation in the Pacific (PTWS). In this context, since 2005, efforts have begun for the establishment of TWSs in the Indian Ocean (IOTWS), in the Caribbean area (C...
Tinti, S.; Graziani, L.; Brizuela, B.; Maramai, A.; Gallazzi, S.
The 2004 Indian Ocean tsunami caused an estimated 230,000 casualties, the worst tsunami disaster in history. A similar-sized tsunami in the Pacific Ocean, generated by the 1960 Chilean earthquake, commenced international collaborations on tsunami warning systems, and in the tsunami research community through the Tsunami Commission of International Union of Geodesy and Geophysics. The IUGG Tsunami Commission, established in 1960, has been holding the biannual International Tsunami Symposium (ITS). This volume contains selected papers mostly presented at the 22nd ITS, held in the summer of 2005. This introduction briefly summarizes the progress of tsunami and earthquake research as well as international cooperation on tsunami warning systems and the impact of the 2004 tsunami. Brief summaries of each paper are also presented.
Satake, K.; Okal, E. A.; Borrero, J. C.
Qualitative research methods play an important role in empirical research practices in practically all humanities and social science disciplines. Qualitative methods are used in many fields and make important scientific contributions. The interest of, and demand from, students and researchers in a broad education in qualitative procedures is consequently very large indeed. At most universities, however, these methods are not well established, while dubious assumptions borne of either prejudic...
Evaluation of earthquake and tsunami on JSFR has been analyzed. For seismic design, safety components are confirmed to maintain their functions even against recent strong earthquakes. As for Tsunami, some parts of reactor building might be submerged including component cooling water system whose final heat sink is sea water. However, in the JSFR design, safety grade components are independent from component cooling water system (CCWS). The JSFR emergency power supply adopts a gas turbine system with air cooling, since JSFR does not basically require quick start-up of the emergency power supply thanks to the natural convection DHRS. Even in case of long station blackout, the DHRS could be activated by emergency batteries or manually and be operated continuously by natural convection. (authors)
Evaluation of earthquake and tsunami on JSFR has been analyzed. For seismic design, safety components are confirmed to maintain their functions even against recent strong earthquakes. As for Tsunami, some parts of reactor building might be submerged including component cooling water system whose final heat sink is sea water. However, in the JSFR design, safety grade components are independent from component cooling water system (CCWS). The JSFR emergency power supply adopts a gas turbine system with air cooling, since JSFR does not basically require quick start-up of the emergency power supply thanks to the natural convection DHRS. Even in case of long station blackout, the DHRS could be activated by emergency batteries or manually and be operated continuously by natural convection. (authors)
Chikazawa, Y.; Enuma, Y.; Kisohara, N.; Yamano, H.; Kubo, S.; Hayafune, H. [Japan Atomic Energy Agency, 4002 Narita, Oarai, Higashi-ibaraki-gun, Ibaraci (Japan); Sagawa, H.; Okamura, S.; Shimakawa, Y. [Mitsubishi FBR Systems Inc., 2-34-17 Jingumae, Shibuya, Tokyo (Japan)
A subcommittee of the IUGG International Tsunami Commission was convened in 2010 to revise and update the 1998 UNESCO-IOC Post-Tsunami Survey Field Guide. The revised Guide addresses the developments in the tsunami field since 1998, the need to accommodate vastly increased amounts of data, and to incorporate disciplines that were not covered in the original guide. The Guide also advocates a systems-approach to assessing tsunami impacts that examines the full range of physical, environmental, and socio-economic effects and their interrelationship, bringing tsunami research efforts into a closer alignment with the UN International Strategy for Disaster Reduction (UNISDR). This Field Guide is intended to provide a flexible framework to facilitate the acquisition of critical data in the immediate aftermath of significant tsunamis and to balance the needs of international researchers with those of communities and agencies involved with response and recovery. It will be of use to a variety of people and organizations who may either participate in, assist in coordination, or host post-tsunami field surveys. It is hoped that this Guide will promote pre-event planning in countries at risk of tsunamis to reduce the stresses of developing organizational logistics in the post-emergency response phase and make the process of conducting an ITST easier and more productive for both participating researchers and host country organizations. A complete draft of the Guide will be presented at the meeting and members of the tsunami community invited to comment.
Dengler, L.; Dominey-Howes, D.; Yamamoto, M.; Borrero, J. C.; Dunbar, P. K.; Fritz, H. M.; Imamura, F.; Kong, L. S.; Koshimura, S.; McAdoo, B. G.; Satake, K.; Yalciner, A. C.; Yulianto, E.
Based on many recent findings such as those for geodetic data from Japan's GEONET nationwide GPS network and geological investigations of a tsunami-inundated Ryujin Lake in Kyushu, we present a revised source rupture model for the great 1707 Hoei earthquake that occurred in the Nankai Trough off southwestern Japan. The source rupture area of the new Hoei earthquake source model extends further, to the Hyuga-nada, more than 70 km beyond the currently accepted location at the westernmost end of Shikoku. Numerical simulation of the tsunami using a new source rupture model for the Hoei earthquake explains the distribution of the very high tsunami observed along the Pacific coast from western Shikoku to Kyushu more consistently. A simulation of the tsunami runup into Ryujin Lake using the onshore tsunami estimated by the new model demonstrates a tsunami inundation process; inflow and outflow speeds affect transport and deposition of sand in the lake and around the channel connecting it to the sea. Tsunamis from the 684 Tenmu, 1361 Shokei, and 1707 Hoei earthquakes deposited sand in Ryujin Lake and around the channel connecting it to the sea, but lesser tsunamis from other earthquakes were unable to reach Ryujin Lake. This irregular behavior suggests that in addition to the regular Nankai Trough earthquake cycle of 100-150 years, there is a hyperearthquake cycle of 300-500 years. These greater earthquakes produce the largest tsunamis from western Shikoku to Kyushu.
Furumura, Takashi; Imai, Kentaro; Maeda, Takuto
The development of real-time tsunami forecast and rapid tsunami warning systems is crucial in order to mitigate tsunami disasters. The present study shows that tsunami prediction from a seismic centroid moment tensor (CMT) solution would work satisfactorily for the 2013 Santa Cruz Islands earthquake (Mw 8.0) tsunami even though the earthquake source had been modeled as a complicated source characterized by two patches of slip in a past study. We numerically solved the equations for a linear dispersive wave on a spherical coordinate system from the initial tsunami height distribution derived from the CMT solution and a classical scaling law for earthquake faults. The tsunami simulations well explain the observed tsunami arrival times, polarities of initial wave, and maximum amplitudes obtained by deep-ocean pressure measurements. The comparison of the simulation results from dispersive and non-dispersive modeling indicates that the dispersive modeling reproduced the observed waveforms better than the conventional non-dispersive approach. Also, the area affected by a maximum height greater than 0.4 m is decreased by approximately 34% by using dispersion modeling. Those results indicate that the tsunami prediction based on CMT solutions is useful for early warning, and the modeling of dispersion can significantly improve performance.
Miyoshi, Takayuki; Saito, Tatsuhiko; Inazu, Daisuke; Tanaka, Sachiko
The equation of state and bulk and shear viscosities are shown to be able to affect the transverse dynamics of a central heavy ion collision. The net entropy, along with the femtoscopic radii are shown to be affected at the 10-20% level by both shear and bulk viscosity. The degree to which these effects help build a tsunami-like pulse is also discussed.
This article focuses on the effect of dispersion in the field of tsunami modeling. Frequency dispersion in the linear long-wave limit is first briefly discussed from a theoretical point of view. A single parameter, denoted as "dispersion time", for the integrated effect of frequency dispersion is identified. This parameter depends on the wavelength, the water depth during propagation, and the propagation distance or time. Also the role of long-time asymptotes is discussed in...
Glimsdal, S.; Pedersen, G. K.; Harbitz, C. B.; Løvholt, F.
Catastrophic tsunamis are described in historical sources for all regions around the Gulf of Cadiz, at least since 60 BC. Most of the known events are associated with moderate to large earthquakes and among them the better studied is 1 November 1755. We present here a review of the events which effects, on the coasts of the Portuguese mainland and Madeira Island, are well described in historical documents or have been measured by tide gauges since the installation of these instruments. For a ...
Baptista, M. A.; Miranda, J. M.
A long section of the Sunda megathrust south of the great tsunamigenic earthquakes of 2004 and 2005 is well advanced in its seismic cycle and a plausible candidate for rupture in the next few decades. Our computations of tsunami propagation and inundation yield model flow depths and inundations consistent with sparse historical accounts for the last great earthquakes there, in 1797 and 1833. Numerical model results from plausible future ruptures produce flow depths of several meters and inund...
Borrero, Jose? C.; Sieh, Kerry; Chlieh, Mohamed; Synolakis, Costas E.
Full Text Available After the Indian Ocean Tsunami 2004 in Aceh, houses and other buildings were reconstructed by government and Non-Governmental Organizations (NGO. The new buildings near the coastline are open directly to similar tsunami attack. The layout of such new residential are normally arranged and aligned as rows of buildings. The front rows of the buildings suffer more tsunami force due to their location that are closer to the beach and the effect of the reflection from the adjacent buildings. This research aims to analyze the tsunami force on buildings of different types, and the effect of other buildings nearby. The research was conducted using a physical model at the Hydraulic and Hydrology Laboratory, Research Centre for Engineering Science, Universitas Gadjah Mada Indonesia. The physical model simulations were carried out in a flume of 24 m long, 1.45 m wide, and 1.5 m high, that was facilitated with tsunami generator based on dam break system. The models of the buildings were made of plywood and were placed in a row perpendicular to the flume. The distance between the buildings was varied to observe the effect of the gaps. The results show that the force on the building depends on the gap between the buildings. Although the effect of the gap was more significant on low buildings, the effect of force on high buildings was more sensitive to the change of the gap size. Simple equation for practical use is proposed to calculate the tsunami force on building with the effect of nearby buildings.
The present article is devoted to the influence of sediment layers on the process of tsunami generation. The main scope here is to demonstrate and especially quantify the effect of sedimentation on seabed vertical displacements due to an underwater earthquake. The fault is modelled as a Volterra-type dislocation in an elastic half-space. The elastodynamics equations are integrated with a finite element method. A comparison between two cases is performed. The first one corresponds to the classical situation of an elastic homogeneous and isotropic half-space, which is traditionally used for the generation of tsunamis. The second test case takes into account the presence of a sediment layer separating the oceanic column from the hard rock. Some important differences are revealed. The results of the present study may partially explain why the great Sumatra-Andaman earthquake of 26 December 2004 produced such a big tsunami. More precisely, we conjecture that the wave amplitude in the generation region may have bee...
Full Text Available The volcanic archipelago of the Aeolian Islands (Sicily, Italy is included on the UNESCO World Heritage list and is visited by more than 200 000 tourists per year. Due to its geological characteristics, the risk related to volcanic and seismic activity is particularly high. Since 1916 the archipelago has been hit by eight local tsunamis. The most recent and intense of these events happened on 30 December 2002. It was triggered by two successive landslides along the north-western side of the Stromboli volcano (Sciara del Fuoco, which poured approximately 2–3×107 m3 of rocks and debris into the Tyrrhenian Sea. The waves impacted across the whole archipelago, but most of the damage to buildings and infrastructures occurred on the islands of Stromboli (maximum run-up 11 m and Panarea.
The aim of this study is to assess the vulnerability of buildings to damage from tsunamis located within the same area inundated by the 2002 event. The assessment is carried out by using the PTVA-3 Model (Papathoma Tsunami Vulnerability Assessment, version 3. The PTVA-3 Model calculates a Relative Vulnerability Index (RVI for every building, based on a set of selected physical and structural attributes. Run-up values within the area inundated by the 2002 tsunami were measured and mapped by the Istituto Italiano di Geofisica e Vulcanologia (INGV and the University of Bologna during field surveys in January 2003. Results of the assessment show that if the same tsunami were to occur today, 54 buildings would be affected in Stromboli, and 5 in Panarea. The overall vulnerability level obtained in this analysis for Stromboli and Panarea are "average"/"low" and "very low", respectively. Nonetheless, 14 buildings in Stromboli are classified as having a "high" or "average" vulnerability. For some buildings, we were able to validate the RVI scores calculated by the PTVA-3 Model through a qualitative comparison with photographs taken by INGV and the University of Bologna during the post-tsunami survey. With the exception of a single structure, which is partially covered by a coastal dune on the seaward side, we found a good degree of accuracy between the PTVA-3 Model forecast assessments and the actual degree of damage experienced by buildings. This validation of the model increases our confidence in its predictive capability. Given the high tsunami risk for the archipelago, our results provide a framework for prioritising investments in prevention measures and addressing the most relevant vulnerability issues of the built environment, particularly on the island of Stromboli.
The International Tsunami Survey Team (ITST-Samoa, Oct 14-23, 2009), and the Report presented to the Government of Samoa (GoS) immediately upon conclusion, was an unprecedented science effort, setting a benchmark for future coordinated international post-tsunami science surveys that will support national early recovery efforts, and through tsunami research, improve tsunami mitigation and preparedness and so build a stronger resilience of coastal communities. By working together, we achieved outcomes much stronger and more valuable than any one of us could produce alone. For the first time, strong principles of professional conduct, mutual respect, collaboration, partnership, and concern for the welfare of the affected communities, were explictly embeded in the work plan. The 29 September 2009 regional tsunami resulted in loss of life and damage to human infrastructure and environmental systems. Common to many tsunamis, international scientists expressed the intent to undertake science assessments. Traditionally, these surveys, sometimes under UNESCO-IOC auspices, have been single-discipline, and conducted individually with moderate government coordination, so that afterward, the country was left with a large integration task to produce a single coherent study. This changed in Samoa, where an integrated and coordinated approach emerged. The ITST-Samoa was comprised of more than 60 scientists (seismologists, geologists, engineers, social scientists, modellers) from Australia, Fiji, French-Polynesia, Italy, Japan, New Zealand and USA who volunteered to work in collaboration with the GoS, Samoa Red Cross Society, Samoa scientists, and non-government representatives. They worked as one survey team to collect data and assist the GoS to prioritise short- and long-term risk reduction strategies. Their novel work (1) partnered with a regional university to include South Pacific expertise and with the GoS to ensure that (a) international scientists worked in a culturally-sensitive and appropriate way and, (b) outputs achieved were relevant to both GoS and ITST scientists; (2) was interdisciplinary and multisectoral to capture a thorough understanding; and (3) used a ‘coupled human-environment systems framework’ to examine vulnerability and resilience before, during and after the tsunami. ITST succeeded because of (1) the scientists’ strong desire to share their knowledge; (2) GoS’s belief that science will improve disaster risk reduction practices; (3) immediate engagement of UN and regional organizations to provide an umbrella framework for working together; (4) local support to provide the ITST’s command center and; (5) dedicated Science Coordinators to manage the scientific planning, logistics, information sharing, and Report preparation. In 2010, UNESCO/IOC will revise its Post-Tsunami Field Survey Guide to document ITST-Samoa best practices and so provide guidance for future International Tsunami Survey Teams.
Kong, L. S.; Steffen, J.; Dominey-Howes, D.; Biukoto, L.; Titimaea, A.; Thaman, R.; Vaa, R.
Data on tsunamis occurring in the Black Sea and the Azov Sea from antiquity up to the present were updated, critically evaluated and compiled in the standard format developed since the 90's for the New European Tsunami Catalogue. Twenty nine events were examined but three of them, supposedly occurring in 557 AD, 815 AD and 1341 or 1343, were very likely falsely reported. Most of the remaining 26 events were generated in Crimea, offshore Bulgaria as well as offshore North Anatolia. For each of...
Papadopoulos, G. A.; Diakogianni, G.; Fokaefs, A.; Ranguelov, B.
Following the devastating tsunami on 26th December 2004, the nations around the Indian Ocean rim have been working together to establish a tsunami warning system (TWS). A critical component for this TWS is the availability of tsunami travel times (TTT) to various coastal and island locations around the Indian Ocean rim. Without the TTT information, no expected times of arrival (ETA) can be included in a real-time tsunami warning. The importance of ETA for the TWS motivated the computation of arrival times of the 2004 tsunami to 250 representative coastal locations from 35 countries. Numerical accuracy in computation of arrival times for the 2004 tsunami was verified from in-situ tide gauge data and satellite track data from Jason-I and Topex/Poseidon in the Indian Ocean and from coastal stations off South Africa. The resulting TTT atlas showed the feasibility of developing a TWS in a relatively short time-span which is a pre-cursor for developing an information dissemination center in the long term. The TTT atlas was widely distributed as an information database to reduce warning times in event of a future tsunami in the Indian Ocean as well as promote awareness amongst the populations dwelling in the littoral belts of the south-Asian countries. Improvements to the TWS have been made by implementing an Artificial Neural Network (ANN) for prediction of ETA at different coastal destinations. The algorithm uses earthquake locations and pre-computed travel times from the ETA database. The advantage of using ANN in a real-time tsunami travel time prediction is that it produces ETA much faster than the TTT atlas and also preserves the consistency of prediction. The ANN model performs rapid computation of ETA (on average of 4 seconds) in comparison to the conventional TTT atlas which takes approximately 60 minutes of computation time for an undetected earthquake location. The correlation is found to be very high for the new data as observed from different combinations of training and testing the ANN. The validation of the ANN model is found to be satisfactory and reliable which suggests its applicability for real-time prediction. The implementation of the ANN model into the TWS would provide faster computation of ETA resulting in critical earlier issuances of warning messages to coastal destinations. The proposed method is expected to have direct practical application for a real-time TWS for the Indian Ocean as well as for the global oceans.
Kumar, B.; Kumar, R.; Dube, S.; Murty, T.; Gangopadhyay, A.; Chaudhuri, A.; Rao, A.
Abstract:Qualitative research is a research method studying subjective meaning of participant’s world about an object researched. Steps of qualitative research in psychology are: researchers select research topic, researchers formulate research questions, researchers design the study, researchers collect data, researchers analyses data, researchers generate findings, researchers validate findings, and researchers writ...
Decision loop analysis allows us to interpret video and photograph evidence of the behavior of people in Sumatra, Thailand and Sri Lanka during the 2004 Indian Ocean earthquake and tsunami, and to identify problems in communication of tsunami warnings to the general population. Decision loop analysis identifies four steps in the response to a threat: observation (of warning signs); orientation (recognition of the significance of those warning signs); decision (on what response to make); action (implementation of that response). In the case of the Indian Ocean tsunami, lack of tsunami awareness generally caused the decision loop to break down at the orientation stage, even where observation of the incoming waves was reinforced by shouted warnings. Where the orientation step was made early, evacuations were often successful. In the zone of strongest felt seismic intensity the population was subject to information overload (even though damage was often limited) and spent the time between the earthquake and the arrival of the tsunami responding to the earthquake: this "blitzkrieg" effect is a significant obstacle to near - source tsunami mitigation. In other cases, the loop broke down at the decision stage: frequently fatal decisions about where to go emphasize the need for clearly signposted tsunami evacuation routes. Decision loop analysis therefore highlights the different components needed in Education for Self Warning and Voluntary Evacuation (ESWAVE) as part of tsunami mitigation. The abundant video and photograph recordings of the 2004 tsunami provide much material for this approach, similar to the films of volcanic eruptions by Maurice and Katia Krafft that have been used to raise awareness of volcanic hazards after the 1985 Armero lahar disaster.
Fahey, P.; Day, S. J.
We present general structure and functionality of the proposed Computerized Workstation for Tsunami Hazard Monitoring (CWTHM). The tool allows interactive monitoring of hazard, tsunami risk assessment, and mitigation - at all stages, from the period of strong tsunamigenic earthquake preparation to inundation of the defended coastal areas. CWTHM is a software-hardware complex with a set of software applications, optimized to achieve best performance on hardware platforms in use. The complex is calibrated for selected tsunami source zone(s) and coastal zone(s) to be defended. The number of zones (both source and coastal) is determined, or restricted, by available hardware resources. The presented complex performs monitoring of selected tsunami source zone via the Internet. The authors developed original algorithms, which enable detection of the preparation zone of the strong underwater earthquake automatically. For the so-determined zone the event time, magnitude and spatial location of tsunami source are evaluated by means of energy of the seismic precursors (foreshocks) analysis. All the above parameters are updated after each foreshock. Once preparing event is detected, several scenarios are forecasted for wave amplitude parameters as well as the inundation zone. Estimations include the lowest and the highest wave amplitudes and the least and the most inundation zone. In addition to that, the most probable case is calculated. In case of multiple defended coastal zones, forecasts and estimates can be done in parallel. Each time the simulated model wave reaches deep ocean buoys or tidal gauge, expected values of wave parameters and inundation zones are updated with historical events information and pre-calculated scenarios. The Method of Splitting Tsunami (MOST) software package is used for mathematical simulation. The authors suggest code acceleration for deep water wave propagation. As a result, performance is 15 times faster compared to MOST, original version. Performance gain is achieved by compiler options, use of optimized libraries, and advantages of OpenMP parallel technology. Moreover, it is possible to achieve 100 times code acceleration by using modern Graphics Processing Units (GPU). Parallel evaluation of inundation zones for multiple coastal zones is also available. All computer codes can be easily assembled under MS Windows and Unix OS family. Although software is virtually platform independent, the most performance gain is achieved while using the recommended hardware components. When the seismic event occurs, all valuable parameters are updated with seismic data and wave propagation monitoring is enabled. As soon as the wave passes each deep ocean tsunameter, parameters of the initial displacement at source are updated from direct calculations based on original algorithms. For better source reconstruction, a combination of two methods is used: optimal unit source linear combination from preliminary calculated database and direct numerical inversion along the wave ray between real source and particular measurement buoys. Specific dissipation parameter along with the wave ray is also taken into account. During the entire wave propagation process the expected wave parameters and inundation zone(s) characteristics are updated with all available information. If recommended hardware components are used, monitoring results are available in real time. The suggested version of CWTHM has been tested by analyzing seismic precursors (foreshocks) and the measured tsunami waves at North Pacific for the Central Kuril's tsunamigenic earthquake of November 15, 2006.
Lavrentiev-Jr, Mikhail; Marchuk, Andrey; Romanenko, Alexey; Simonov, Konstantin; Titov, Vasiliy
The 26 December 2004 Tsunami resulted in a death toll of >270,000 persons, making it the most lethal tsunami in recorded history. This article presents performance data observations and the lessons learned by a civilian team dispatched by the Australian government to "provide clinical and surgical functions and to make public health assessments". The team, prepared and equipped for deployment four days after the event, arrived at its destination 13 days after the Tsunami. Aspiration pneumonia, tetanus, and extensive soft tissue wounds of the lower extremities were the prominent injuries encountered. Surgical techniques had to be adapted to work in the austere environment. The lessons learned included: (1) the importance of team member selection; (2) strategies for self-sufficiency; (3) personnel readiness and health considerations; (4) face-to-face handover; (5) coordination and liaison; (6) the characteristics of injuries; (7) the importance of protocols for patient discharge and hospital staffing; and (8) requirements for interpreter services. Whereas disaster medical relief teams will be required in the future, the composition and equipment needs will differ according to the nature of the disaster. National teams should be on standby for international response. PMID:16602269
Bridgewater, Franklin H G; Aspinall, Edward T; Booth, Joy P M; Capps, Roger A; Grantham, Hugh J M; Pearce, Andrew P; Ritchie, Brett K
Full Text Available In the last years several numerical codes have been developed to analyse tsunami waves. Most of these codes use a finite difference numerical approach giving good results for tsunami wave propagation, but with limitations in modelling inundation processes. The HyFlux2 model has been developed to simulate inundation scenario due to dam break, flash flood and tsunami-wave run-up. The model solves the conservative form of the two-dimensional shallow water equations using a finite volume method. The implementation of a shoreline-tracking method provides reliable results. HyFlux2 robustness has been tested using several tsunami events. The main aim of this study is code validation by means of comparing different code results with available measurements. Another objective of the study is to evaluate how the different fault models could generate different results that should be considered for coastal planning. Several simulations have been performed to compare HyFlux2 code with SWAN-JRC code and the TUNAMI-N2. HyFlux2 has been validated taking advantage of the extensive seismic, geodetic measurements and post-tsunami field surveys performed after the Nias March 28th tsunami. Although more detailed shallow bathymetry is needed to assess the inundation, diverse results in the wave heights have been revealed when comparing the different fault mechanism. Many challenges still exist for tsunami researchers especially when concern to early warning systems as shown in this Nias March 28th tsunami.
Full Text Available Hydrostatic (HY and non-hydrostatic (NHY tsunami physics is compared by application to the Kuril Island Tsunami (KIT of November 2006 and the Japan Tsunami (JT of March 2011. Our purpose is to study the significance of dispersive vs. non-dispersive long waves on global tsunami propagation. A tool which is well suited to revealing tsunami wave transformations is the energy flux. Expressions for dispersive and non-dispersive fluxes have been formulated. This provides an understanding of the role of dispersion in tsunami propagation and dissipation. Separating the pressure field into two parts i.e., HY and NHY shows that dispersive waves extract energy from the main wave, directing the dispersive energy flux away from the wave front. The major result of the application of the energy flux to non-dispersive waves is an enhanced understanding of later tsunami wave train arrivals at distant points – with arrivals sometimes occurring several hours after an initial forerunner wave. Computations show that strong differences between non-dispersive and dispersive waves develop along the length of the main energy beam. This has important consequences for accurate tsunami prediction and warnings.
Full Text Available The sea levels recorded in the wake of Indian Ocean Tsunami of December 2004 and of the Kuril Island Tsunami of November 2006 show strong tsunami signal enhancement of the late arriving secondary waves. Using these tsunami eventswe demonstrate thatsudden changes caused by higher energy pulses in the intermittent tsunami wave trains can be assessed by energy fluxes. Therefore, to delineate the regions of tsunami wave amplification and travel time we propose to use energy flux.A series of numerical experimentsdefinedinexplicitwaythe bathymetric features which scatter tsunami signal towards ports, like Crescent City. Identification of the distant bathymetric featureswas achievable sincethe energy fluxvectordelineatedthe energy pathways that coupled distant bathymetric features to portslocated thousands of kilometers apart. Calculations of the energy flux vector involves simple formulas based on two components of velocity and sea level. The maximum of the energy flux (which has no directional properties can be evaluated from the sea level amplitude, hence both observed and computed sea level can be used for this purpose. The main task of this paper is to suggest that tsunami warning and prediction services should use numerical-hydrodynamical models with wider scope of physical processes by incorporating the energy balance equation into presently used tools.
Maximum expected tsunami amplitudes, currents, and travel times to 185 locations on the coast of British Columbia from four different earthquake epicentres are tabulated. This information is used by the regional tidal superintendent in arriving at the advice that is provided to the Provincial Emergency Program in the case of a real tsunami event. (author). 2 refs, 4 figs, 6 tabs
Recent centuries provide no precedent for the 2004 Indian Ocean tsunami, either on the coasts it devastated or within its source area. The tsunami claimed nearly all of its victims on shores that had gone 200 years or more without a tsunami disaster. The associated earthquake of magnitude 9.2 defied a Sumatra-Andaman catalogue that contains no nineteenth-century or twentieth-century earthquake larger than magnitude 7.9 (ref. 2). The tsunami and the earthquake together resulted from a fault rupture 1,500 km long that expended centuries' worth of plate convergence. Here, using sedimentary evidence for tsunamis, we identify probable precedents for the 2004 tsunami at a grassy beach-ridge plain 125 km north of Phuket. The 2004 tsunami, running 2 km across this plain, coated the ridges and intervening swales with a sheet of sand commonly 5-20 cm thick. The peaty soils of two marshy swales preserve the remains of several earlier sand sheets less than 2,800 years old. If responsible for the youngest of these pre-2004 sand sheets, the most recent full-size predecessor to the 2004 tsunami occurred about 550-700 years ago. ??2008 Macmillan Publishers Limited. All rights reserved.
Jankaew, K.; Atwater, B.F.; Sawai, Y.; Choowong, M.; Charoentitirat, T.; Martin, M.E.; Prendergast, A.
Large tsunamis cause significant changes in coastal ecosystems. They include modifications in shoreline position, sediment erosion and deposition, new initial soil formation, salination of soils and waters, removal of vegetation, as well as direct impact on humans and infrastructure. The processes and rate of coastal zone recovery from large tsunamis has been little studied but during the last decade a noteworthy progress has been made. This study focus on comparison of recovery processes in various climatic zones, namely in monsoonal-tropical, temperate and polar zone. It is based on own observation and monitoring in areas affected by 2004 Indian Ocean Tsunami in Thailand, 2011 Tohoku-oki tsunami in Japan and 2000 Paatuut landslide-generated tsunami in Vaigat Strait (west Greenland), as well as on review of published studies from those areas. The particular focus is on physical and biological recoveries of beaches, recovery of coastal vegetation, new soil formation in eroded areas and those covered by tsunami deposits, marine salt removal from soils, surface- and groundwater, as well as landscape adjustment after the tsunamis. The beach zone - typically the most tsunami-eroded zone, has been recovered already within weeks to months and has been observed to be in the pre-tsunami equilibrium stage within one year in all the climate zones, except for sediment-starved environments. The existing data on beach ecosystems point also to relatively fast recovery of meio- and macrofauna (within weeks to several months). The recovery of coastal vegetation depends on the rate of salt removal from soils or on the rate of soil formation in case of its erosion or burial by tsunami deposits. The salt removal have been observed to depend mainly on precipitation and effective water drainage. In tropical climate with seasonal rainfall of more 3000 mm the salt removal was fast, however, in temperate climate with lower precipitation and flat topography the salinities still exceeded the recommended concentrations for freshwater plants after one year. The new soil formation and vegetation recovery depends mainly on the rate of biological production. In tropical climate the vegetation largely recovered already after the first rainy season and supported the new soil formation. In temperate climate this process was much slower, in particular in flat lying areas and on coastal dunes with poor sandy soils. In polar climate only limited vegetation recovery (mainly of Salix species) has been observed after 12 years and vegetation withered due to salt stress still marked the tsunami inundation limit and the new soil formation was very slow and focused on low lying, wet areas buried with thin tsunami deposits cover. The post-tsunami recovery processes may be grouped into climate-related (vegetation recovery, removal of salts from soils) and non climate-related (e.g. beach recovery) or modified by climatic and local factors (for instance, the rate of tsunami deposits reworking and thus new soil formation). The rate of recovery varies from days / weeks as in case of beach recovery to several decades as in case of new soil formation on tsunami deposits. The study was partly funded by Polish National Science Centre grant No. 2011/01/B/ST10/01553. The review results from studies in collaboration with number of researchers from Australia, Japan, Poland, Thailand, United Kingdom and United States to whom I express sincere thanks.
This animation shows a model of the tsunami generated by the June 23, 2001 Peru earthquake. The first 33 minutes of tsunami propagation are shown. The tsunami is generated very near the coast and propagates outward to the Pacific Basin and along the coastline to the north and south. Largest offshore tsunami amplitudes are in the Chala-Camaná region of southern Peru.
At least six layers of tsunami deposit during the recent 500 years were found in a small valley on the Sanriku coast, just north of Taro (Miyako city, Iwate prefecture), where the 2011 tsunami heights from the Tohoku earthquake ranged from 17 to 34 m. The Sanriku coast is a Ria coast characterized by sawtooth-shaped coastline. Because of the steep-sloped valleys, alluvial deposits are very limited and tsunami traces are difficult to be preserved. Around the survey site, however, a marsh is separated from open sea by a beach ridge with the maximum altitude of about 4.5 m above mean sea level. In the marsh, well-decomposed peat has been developed. The sand deposits were brought by large tsunamis over the beach ridge and preserved in the marsh peat. We conducted drilling survey using the 3-m long Geo-slicer, trench survey, and outcrop observations. We sketch the sedimentary structure, conduct grain size analysis, reconstruct paleo-environment from microfossils, estimate the deposition age on the basis of radiocarbon dating and 210Pb/137Cs analysis, and correlate them with historical tsunamis. The uppermost sand layer which covers the ground surface is probably due to the 2011 tsunami. At least six event deposit layers can be identified in Geo-slicer's sample. Some sandy layers show normal or inverse grading structures and/or lamination, indicating a strong water flow. Some sand layers can be traced up to 400 m inland from the coast, while others can be identified only near the coast. The sandy layers well correlate with abrupt increases in marine microfossils floating near the sea surface. We use it as indicators of inflow of sea water into the marsh. The bottom peat layer of Geo-slicer's sample shows the AD 15th century, indicating that all the sand layers are from tsunamis in historical age during the recent 500 years. These tsunami deposits can be correlated with local tsunamis or distant tsunamis on the basis of radiocarbon dating and 210Pb/137Cs analysis. According to Japanese historical documents, candidates of tsunamis are from the 2011 Tohoku earthquake, the 1933 and 1896 Sanriku earthquakes, the 1793 Miyagi-oki earthquake, the 1763 Aomori-oki earthquake, the 1677 Boso-oki earthquake, and the 1611 Sanriku earthquake. Some trans-Pacific tsunamis such as the 1700 Cascadia and 1960 Chilean tsunamis also caused severe damage along the Sanriku coast and these tsunami deposits may be also preserved.
Goto, T.; Satake, K.; Sugai, T.; Ishibe, T.; Harada, T.; Murotani, S.
Based on recent findings of geodetic and geological investigations, we present a revised source-rupture model for the great 1707 Hoei earthquake that occurred in the Nankai Trough off southwestern Japan. Of the series Nankai Trough M8 earthquakes that recur approximately every 100 to 150 years, the Hoei earthquake is considered to be the largest shock. Its fault rupture extended from Suruga Bay to the westernmost end of Shikoku, more than 700 km. However, many recent findings, such as those based on geodetic data from Japan’s GEONET nationwide GPS network and geological investigations of a tsunami-inundated lake in Kyushu have claimed that the source rupture area of the Hoei earthquake should extend further, to the Hyuga-nada, more than 70 km beyond the currently accepted location. Numerical simulation of the tsunami using a new source-rupture model for the Hoei earthquake explains the distribution of the very high tsunami observed along the Pacific coast from western Shikoku to the Hyuga-nada more consistently than though those derived from former source models. A simulation of the tsunami run-up into Ryujin Lake using the onshore tsunami estimated by the new model demonstrates a tsunami inundation process; a larger tsunami with large amount of water flux transporting sea sand to the lake through a narrow channel connecting the sea and the lake and the sand could leave behind when the tsunami retreated back to the sea. The results of tsunami inundation simulation confirmed that Ryujin Lake could not be inundated by a tsunami unless the fault rupture of the Nankai Trough earthquake extend beyond the westernmost end of Shikoku. This is the most of the case of the Nankai Trough earthquakes such as during the 1854 Ansei Nankai and 1946 Showa Nankai earthquakes and their tsunamis were shorter and the ground surface did not subside in the area around the Ryujin Lake. The irregular sedimentation properties of tsunami-induced deposits in Ryujin Lake with unusually large tsunami such as from the 684 Tenmu and 1361 Shokei earthquakes warn that the history of Nankai Trough earthquake occurrences is not so simple. There may be a hyper-earthquake cycle of approximately 300 to 500 years that causes larger tsunamis along the Pacific coast from western Shikoku to Kyushu.
Furumura, T.; Imai, K.; Maeda, T.
Full Text Available The Tsunami Assessment Modeling System was developed by the European Commission, Joint Research Centre, in order to serve Tsunami early warning systems such as the Global Disaster Alerts and Coordination System (GDACS in the evaluation of possible consequences by a Tsunami of seismic nature. The Tsunami Assessment Modeling System is currently operational and is calculating in real time all the events occurring in the world, calculating the expected Tsunami wave height and identifying the locations where the wave height should be too high. The first part of the paper describes the structure of the system, the underlying analytical models and the informatics arrangement; the second part shows the activation of the system and the results of the calculated analyses. The final part shows future development of this modeling tool.
On March 11, 2011, the Great East Japan Earthquake and subsequent Tsunami caused a nuclear accident in Fukushima Daiichi nuclear power plants (NPPs), which led to massive social fear of the NPPs. The Japan Society of Maintenology organized a special committee to develop a methodology of assessing the safety of Japanese NPPs that the short-term measures against large tsunami had been taken after March 11. The vigorous study and discussion resulted in the 'Guideline for Assessing Large Tsunami Countermeasures in Japanese Nuclear Power Plants'. By applying it, robustness of NPPs (37 units not including TEPCO plants) against large tsunami had been assessed. This article explained background of preparing the guideline, its contents, and evaluated results by applying it, and further needed activities. Waterproofing and multiplicity of batteries and reinforcement of external power such as small-sized gas turbines installed near NPPs would contribute much to upgrade safety of NPPs against large tsunami. (T. Tanaka)
Fifteen papers are included in Volume 2 of a PAGEOPH topical issue Tsunamis in the World Ocean: Past, Present, and Future. These papers are briefly introduced. They are grouped into three categories: reports and studies of recent tsunamis, studies on tsunami statistics and application to tsunami warning, and modeling studies of tsunami runup and inundation. Most of the papers were presented at the 24th International Tsunami Symposium held 14-16 July 2009 in Novosibirsk, Russia, and reflect the current state of tsunami science.
Satake, Kenji; Rabinovich, Alexander; Kâno?lu, Utku; Tinti, Stefano
Real-time detection of a tsunami on instrumental sea-level records is quite an important task for a Tsunami Warning System (TWS), and in case of alert conditions for an ongoing tsunami it is often performed by visual inspection in operational warning centres. In this paper we stress the importance of automatic detection algorithms and apply the TEDA (Tsunami Early Detection Algorithm) to identify tsunami arrivals of the 2011 Tohoku tsunami in a real-time virtual exercise. TEDA is designed to ...
Bressan, L.; Tinti, S.
Full Text Available The potential impact of past Caribbean tsunamis generated by earthquakes and/or massive submarine slides/slumps, as well as the tsunamigenic potential and population distribution within the Intra-Americas Sea (IAS is examined to help define the optimal location for coastal sea level gauges intended to serve as elements of a regional tsunami warning system. The goal of this study is to identify the minimum number of sea level gauge locations to aid in tsunami detection and provide the most warning time to the largest number of people. We identified 12 initial, prioritized locations for coastal sea level gauge installation. Our study area approximately encompasses 7oN, 59oW to 36oN, 98oW. The results of this systematic approach to assess priority locations for coastal sea level gauges will assist in developing a tsunami warning system (TWS for the IAS by the National Oceanic and Atmospheric Administration (NOAA and the Regional Sub-Commission for the Caribbean and Adjacent Regions (IOCARIBE-GOOS.
Joshua I. Henson
Full Text Available The city of Algiers and the surrounding coastal areas in northern Algeria are vulnerable to earthquakes which range from moderate to severe. In 2006, using several possible earthquake scenarios for the Western Mediterranean, the Japan International Cooperation Agency and the Algerian National Seismic Engineering Research Center predicted that heavy damage could occur in the Algiers region. Algerian Civil Defense authorities are particularly concerned by the threat of near-field earthquakes, associated slides and rock falls, as well as for tsunamis that can be generated. The present study proposes a new tsunami risk scale that provides information about the exposed communities and infrastructure, which can be used for regional tsunami alerts and warnings. Furthermore, it evaluates the vulnerability along the Bay of Algiers from tsunamigenic earthquakes. The JMA seismic intensity scale (Shindo scale and the corresponding seismic peak ground accelerations are used in the evaluation. The results of tsunami modeling studies and of earthquake vulnerability assessment described by the present study, emphasize the significance of public education and preparedness in efforts to mitigate loss of life and damage to property.
L. A. Amir
In this study, a tsunami hazard curve was determined for a probabilistic safety assessment (PSA) induced tsunami event in Nuclear Power Plant site. A Tsunami catalogue was developed by using historical tsunami record which happen before 1900 and instrumental tsunami record after 1900. For the evaluation of return period of tsunami run-up height, power-law, uppertruncated power law and exponential function were considered for the assessment of regression curves and compared with each result. Although the total tsunami records were only 9 times at the east coast of Korea during tsunami catalogue, there was no such research like this about tsunami hazard curve evaluation and this research lay a cornerstone for probabilistic tsunami hazard assessment (PTHA) in Korea
The 2011 Tohoku earthquake caused more than 20,000 casualties, with most of the dead and missing in an enormous tsunami. Survivors had simply evacuated to higher ground within approximately 30 minutes of its arrival. This reflects the importance of public perception of tsunami risks represented by its heights. Our question is how the devastating tsunami affected people in the western Japan where a great earthquake is anticipated in near future. Existing risk analysis researches show that the experience of natural disasters increases risk perception, even with indirect experiences such as seeing photographs of disaster scenes or thinking about a major natural calamity. No doubt, we can assume that the devastating tsunami would have led people to have a greater sense of associated risks. Our result, however, shows that the destructive tsunami of Tohoku earthquake lowered the risk assessment of tsunami heights. One possible explanation to this paradoxical result is the anchoring heuristic. It defines that laypersons are highly inclined to judge based on the numbers first presented to them. Media's repeating report of record-breaking tsunamis of 30 m or more anchored people to elevate the height to evacuate. The results of our survey pose a significant problem for disaster prevention. The survey area is at high risk of giant earthquake, and according to our results, more than 50% of the people surveyed no longer sensed the danger of a 1-m-high tsunami, whereas about 70% had perceived its peril before the Tohoku earthquake. This is also of great importance in Indonesia or Chile where huge earthquakes had occurred recently. We scientists need to face up to the fact that improvement of quick calculation of tsunami heights is not sufficient at all to mitigate the tsunami disasters, but reorient how we should inform laypersons to evacuate at the emergency situation.
Oki, S.; Nakayachi, K.
Timely prediction of tsunami wave parameters is still among actual problems for tsunami risk mitigation. After the Great East Japan Earthquake (Mach 11, 2011) it takes only 20 minutes for tsunami wave to approach the cost of Japan after the quake. Existing models and software applications allow experts to simulate tsunami wave propagation rather fast. However, all the models require knowledge about initial see-face disturbance at tsunami source. Seismic data, available right after the event, provide the information about earthquake magnitude and epicenter location. There are a number of approaches to evaluate the initial see-face disturbance (using knowledge about the trench geo structure, satellite imaging, etc.). One of perspective approaches is to recalculate tsunami wave profiles, recorded by deep-ocean stations like DART buoys or GPS equipment, in terms of initial sea surface displacement. The so-called preliminary calculation strategy suggests that the targeted subduction zone is covered by a number rectangular "unit sources" 50x100 km. Wave propagation from each unit source, caused by the unified shape (typical for the given subduction zone), is calculated in advance other the entire aquatoria. After real event the wave profile, measure at certain sensor, is approximated as linear combination of model signals from the above unit sources, calculated at the same point. Method was proved to be rather accurate. However, it takes valuable time to recover initial displacement at tsunami source in case of larger zone of disturbance (e.g. about 20 minutes for processing tsunami epicenter covered with six unit-sources). We suggest new algorithm for above mentioned model. This is based on Fourier theory and involves orthogonal decomposition of simulated profiles, calculated from the unit sources. It takes only about 1 second to recover tsunami source of twenty unit-sources. This allows one to speak about possibility to develop real-time system for evaluating tsunami.
Lavrentyev, Mikhail; Titov, Vasily; Romanenko, Alexey
Tsunami and storm surges result in unusual oscillation of seal level, flooding the coastal zones and constitute the major marine disasters in China. Damage by storm surges occurs frequently. According to statistics there are 14 storm surge events exceeding 1 every year on the average. Six of them are typhoon surges and the other eight are extra-tropical surges. In general, in China, there is one severe disaster of storm surge every two years. Monitoring, forecasting and warning for storm surges, including the drop of water level, are the major part of the operational oceanographic services in China. Such a warning system has been set up and is operated by the State Oceanic Administration since 1974. The results of the historical study of tsunami in the last few years pointed out that the anomaly of sea level generated by tele-tsunamis originating in the Pacific Ocean Basin is less than 30 cm on the mainland coast, but local tsunami in the China Seas can be very dangerous. For example, more than 50,000 people were killed by a tsunami in Taiwan and in Taiwan Strait in 1781. It resulted in more deaths than any other tsunami in recorded history. However, the frequency of tsunami disaster is very low for the coast of China, averaging only one every 100 years. It is impossible to set up an independent tsunami warning system in China. It is more practical to set up an integrated warning system on tsunami and on storm surges consisting of: A sea level observing network with rg of: A sea level observing network with real time sea level data acquisition capability; A monitoring system of weather causing the storm surges and of seismic stations monitoring tsunamigenic earthquakes; A tidal prediction scheme for operational use; A forecasting scheme for storm surges and tsunami analysis; The means for warning dissemination. (author). 8 refs, 4 figs, 3 tabs
Full Text Available In this paper, we present a CONTROL volume model for tsunami incitement process by combining the Navier-Stokes equation, the jet theory and relative velocity model. We conclude that the initial condition for tsunami propagation simulation is equivalent to the static near-field seismic displacement of earthquake that induces the tsunami. The error analyzed from this method is only about 1 percent for a common seafloor earthquake, and it is consistent with the result of Ansys/Ls-dyna numerical analysis. EDGRN/EDCMP and COMCOT program provide some new acquirement for the tsunami studies. In the second part of the paper, we develop a site-selection method for anchor-grounded tsunami observation in Chinese eastern sea.
We consider recent ocean-bottom earthquakes for which detailed slip distribution data are available. Using these data and the Okada formulae, we calculate the vector fields of co-seismic bottom deformations, which allow us to determine the displaced water volume and the potential energy of initial elevation of the tsunami source. It is shown that, in the majority of cases, the horizontal components of bottom deformation provide an additional contribution to the displaced water volume and virtually never diminish the contribution of the vertical component. The absolute value of the relative contribution of the horizontal components of bottom deformation to the displaced volume varies from 0.07 to 55 %, on average amounting to 14 %. The displaced volume and the energy of initial elevation (tsunami energy) are examined as functions of the moment magnitude, and the relevant regressions (least-squares fits) are derived. The obtained relationships exhibit good correspondence with the theoretical upper limits that had been obtained under the assumption of uniform slip distribution along a rectangular fault. Tsunami energy calculated on the basis of finite fault model data is compared with the earthquake energy determined from the energy-magnitude relationship by Kanamori. It is shown that tsunami takes from 0.001 to 0.34 % of the earthquake energy, and on average 0.04 %. Finally, we analyze the Soloviev-Imamura tsunami intensity as a function of the following three quantities: (1) the moment magnitude, (2) the decimal logarithm of the absolute value of displaced volume, and (3) the decimal logarithm of the potential energy of initial elevation. The first dependence exhibits rather poor correlation, whereas the second and third dependences demonstrate noticeably higher correlation coefficients. This gives us grounds to suggest considering the displaced volume and the energy of initial elevation as measures of the tsunamigenic potential of an earthquake.
Nosov, Mikhail A.; Bolshakova, Anna V.; Kolesov, Sergey V.
Tsunami invaded the eastern coastlines of Mindanao islands several minutes after the strong ground shaking of the May 17, 1992 quake. Recent field investigations showed that tsunami intensity generally decreases southwards and northwards relative to Bunga and Zaragoza areas. There was an unusually high tsunami wave height (~6m) at Bunga that was most probably due to local site effect. Tsunami waves were generally preceded by the lowering of sea water level while the tsunami arrival times have...
Besana, Glenda M.; Masataka Ando; Ma. Hannah Mirabueno
Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish [...] Abstract in english A short compilation of the cause, characteristics and effects of the tsunami generated on the 26 of December of 2004 in Indonesia is presented here. The general context of generation of this phenomena is illustrated together with the tectonic environment in which this tsunami in particular was produ [...] ced. Finally, a brief introduction to tsunamis in Colombia including tsunami cases and areas of higher tsunami hazard is considered.
BEATRIZ ELENA, ESTRADA ROLDÁN; JOSEF, FARBIARZ FARBIARZ.
Due to lack of sufficient historical data of tsunami in the Makran subduction zone (MSZ) at the northwestern Indian Ocean, a probabilistic method is employed to assess the tsunami hazards in this region. The method employs a combination of probability evaluation of offshore earthquake occurrence and numerical modeling of tsunami to determine the probability of tsunami wave height exceeding a certain level. The method allowed us to determine the likelihood of tsunami in the region ...
Heidarzadeh, Mohammad; Kijko, Andrzej
Evaluation of the effects of tsunami damage relative to earthquake damage may help to identify critical coastal zone structures and exposed populations for near field tsunami risk. In this work, we propose to define the ratio between tsunami intensity and earthquake intensity as a measure of near field tsunami vulnerability for coastal communities. This parameter is estimated for 13 tsunami events reported in North Algeria from the 14th century to present. Although the results show that there...
ALGERIA’S VULNERABILITY TO TSUNAMIS FROM NEAR-FIELD SEISMIC SOURCES; Cisternas, A.; -l Vigneresse, J.; Dudley, W.; Mc Adoo, B.
In 2005, Dr. Robert Wiegel compiled “Tsunami Information Sources”. The compilation has been made available via a website and has been published as an issue in Science of Tsunami Hazards. The compiled references have been assigned keyword descriptions, and compiled in order to review the breath and depth of Tsunami Science publications.The review indicates that tsunami research involves eight major scientific disciplines: Geology, Seismology, Tsunami Science, Engineering, Disaster Manageme...
Keating, Barbara H.
This paper presents tsunami intensity mapping and damage patterns along the surveyed coast of Tamilnadu (India) of the deadly Indian Ocean tsunami of December 26, 2004. The tsunami caused severe damage and claimed many victims in the coastal areas of eleven countries bordering the Indian Ocean. A twelve-stage tsunami intensity scale proposed by Papadopoulos and Imamura (2001) was followed to assign the intensity at the visited localities. Along the coast of the Indian mainland, tsunami damage sustained exclusively. Most severe damage was observed in Nagapattinam Beach, Nabiyarnagar, Vellaipalyam, and the Nagapattinam Port of Nagapattinum District on the east coast and Keelamanakudy village of Kanyakumari District on the western coast of Tamilnadu. The maximum assigned tsunami intensity was X+ at these localities. Minimum intensity V+ was received along the coast of Thanjavur, Puddukkotai and Ramnathpuram Districts in Palk Strait. The general observation reported by many people was that the first arrival was a tsunami crest. The largest tsunami waves were first arrivals on the eastern coast and the second arrivals on the western coast. Along the coast, people were unaware of the tsunami, and no anomalous behavior of ocean animals was reported. Good correlation was observed between the severity of damage and the presence of shadow zone of Sri Lanka, reflected waves from Sri Lanka and the Maldives Islands, variation in the width of the continental shelf, elevation of the coast and the presence of breakwaters. The presence of medu (naturally elevated landmass very close to the sea shore and elongated parallel to the coast) reduced the impact of the tsunami on the built environment.
Narayan, J. P.; Sharma, M. L.; Maheshwari, B. K.
Full Text Available Qualitative methods and insights from other disciplines are increasingly integrated into demography's traditionally quantitative toolkit. Whereas this is not problematic for multi-disciplinary research projects difficulties may arise when quantitatively trained demographers diversify to use less familiar data collection tools. We review the scale of this recent trend and the choice of qualitative methods typically employed by demographic researchers. Using insights from a comparative qualitative study undertaken in Zimbabwe and Senegal, we discuss some problems inherent in qualitative data collection and analysis and propose ways in which such data should and should not be used. Focussing in particular on semi-structured in-depth interviews, we discuss issues of representativity, investigate respondents' silence on specific topics, and the role of interviewer characteristics in influencing the interview subject matter.
Advances in the understanding and prediction of tsunami impacts allow the development of risk reduction strategies for tsunami-prone areas. This paper presents an integral framework for the formulation of tsunami evacuation plans based on tsunami vulnerability assessment and evacuation modelling. This methodology considers (i) the hazard aspects (tsunami flooding characteristics and arrival time), (ii) the characteristics of the exposed area (people, shelter...
Gonza?lez-riancho, P.; Aguirre-ayerbe, I.; Aniel-quiroga, I.; Abad, S.; Gonza?lez, M.; Larreynaga, J.; Gavidia, F.; Gutie?rrez, O. Q.; A?lvarez-go?mez, J. A.; Medina, R.
In response to the 2004 Indian Ocean Tsunami, and in anticipation of new license applications, the United States Nuclear Regulatory Commission (US NRC) initiated a long-term research program to improve understanding of tsunami hazard levels for coastal facilities on the U.S. Atlantic and Gulf Coasts. For this effort, the US NRC organized a collaborative research program with researchers at the United States Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA). Key researchers from universities and other groups have also made important contributions to this program. The work undertaken represents the combined effort of a diverse group of marine geologists, geophysicists, geotechnical engineers, and hydrodynamic modelers. The Atlantic and Gulf coasts are the focus of this program due to the number of existing and proposed nuclear facilities located on these coasts and because less is generally known about tsunami hazard on these coasts. Because the US NRC is interested in understanding hazard associated with the rare large tsunami that may occur over long time periods (in excess of 10,000 years), the research program considers both seismic and landslide tsunamigenic sources. It also includes the study of both large far-field sources and near-field sources. The study of tsunamigenic landslides is a key difference between this research program and other tsunami hazard assessment programs. In the initial phase, significant effort was focused on identifying and characterizing offshore near-field landslides and on understanding their regional distribution along the coasts. Once early results were obtained, modeling of one of the larger slides was initiated to better understand the hazard posed by the slides identified. Important properties of the slide, such as flow velocity, were characterized through work that included analysis of the dynamic elements. The research related to far-field tsunamigenic landslides has similarly focused on collecting existing information and assessing the potential impact to the coasts. The focus of seismic sources focused on the Hispaniola-Puerto Rico-Lesser Antilles subduction zone and the enigmatic zone of large earthquakes west of Gibraltar. These source areas were investigated, an evaluation of their tsunamigenic potential was undertaken, and the potential for hazard to the U.S. coastline was considered. As part of the current phase, the USGS will conduct field investigations in key locations for the purpose of filling existing data gaps. Investigations will also continue to assess landslide potential in the Gulf of Mexico and to determine the source of the 1755 Lisbon earthquake. The potential for developing tools and data to undertake probabilistic tsunami hazard assessments (PTHA) will also be a key focus of later phases of the program. Simultaneously, the NOAA MOST tsunami generation and propagation model is being enhanced to include landslide-based initiation mechanisms and is being validated with case studies. The enhanced MOST model will be used to investigate the tsunamigenic sources characterized by the USGS, with the goal of creating an estimation of deterministic tsunami hazard levels for the length of Atlantic and Gulf Coasts.
Kammerer, A. M.; ten Brink, U. S.; Titov, V. V.
We study finite automata running over infinite binary trees and we relax the notion of accepting run by allowing a negligible set (in the sense of measure theory) of non-accepting branches. In this qualitative setting, a tree is accepted by the automaton if there exists a run over this tree in which almost every branch is accepting. This leads to a new class of tree languages, called the qualitative tree languages that enjoys many properties. Then, we replace the existential quantification --...
Carayol, Arnaud; Haddad, Axel; Serre, Olivier
A methodology of tsunami PSA was developed in this study. A tsunami PSA consists of tsunami hazard analysis, tsunami fragility analysis and system analysis. In the case of tsunami hazard analysis, evaluation of tsunami return period is a major task. For the evaluation of tsunami return period was evaluated with empirical method using historical tsunami record and tidal gauge record. For the performing a tsunami fragility analysis, procedure of tsunami fragility analysis was established and target equipment and structures for investigation of tsunami fragility assessment were selected. A sample fragility calculation was performed for the equipment in a Nuclear Power Plant. For the system analysis, accident sequence of tsunami event was developed according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. For the application to the real nuclear power plant, the Ulchin 56 NPP which is located on the east coast of Korean peninsula was selected. Through this study, whole tsunami PSA (Probabilistic Safety Assessment) working procedure was established and an example calculation was performed for one nuclear power plant in Korea
This portal provides information on the seismicity and plate tectonics of the active boundary between the North American plate and the northeast corner of the Caribbean plate, and the research program being conducted there by the United States Geological Survey (USGS). There are links to maps and remote imagery of the plate boundary and the Caribbean Trench, and to publications and news articles on seismic and tsunami hazards, seafloor mapping, plate interactions, and submarine slides. There is also a movie that describes the geologic background and USGS research efforts in the area.
Full Text Available Abstract:Qualitative research is a research method studying subjective meaning of participant’s world about an object researched. Steps of qualitative research in psychology are: researchers select research topic, researchers formulate research questions, researchers design the study, researchers collect data, researchers analyses data, researchers generate findings, researchers validate findings, and researchers write research report. Some of the qualitative research designs are grounded research, phenomenology research, case study research, and ethnography research. In some situations, researchers often meet questions that reach beyond the prescription of the APA ethical guidelines concerning human participants. Researchers of qualitative research in psychology can generalize their research findings to other people, times, or treatments to the degree to which they are similar to other people, times, or treatments in the original research (naturalistic generalization. There are some strategies for expanding qualitative research as a research approach so the methodology can be accepted as one significant method in understanding psychological phenomena. Keywords:qualitative research, psychology.
Pérdidas de vidas, viviendas, infraestructura y embarcaciones por el tsunami del 27 de Febrero de 2010 en la costa central de Chile / Casualties, housing, infrastructure and vessel losses due to the February 27, 2010 Chile tsunami on the central coast of Chile
Full Text Available SciELO Chile | Language: Spanish Abstract in spanish El terremoto Mw = 8.8 del 27 de febrero de 2010 en Chile se encuentra entre los sismos de mayor magnitud registrados por instrumentos a la fecha, posicionándose como el segundo más fuerte en la historia del país y uno de los diez más fuertes en el mundo registrados mediante instrumentos. Una de sus [...] principales consecuencias fue la generación de un tsunami destructivo por la deformación del fondo marino. Las olas asolaron casi 600 km de la costa de Chile central y fueron la causa de un tercio de las víctimas fatales (181 sobre un total de 521), convirtiéndose así en el tsunami con mayor número de muertes asociadas a este tipo de eventos en Sudamérica en los últimos 30 años. En el presente trabajo se reúnen y sistematizan una serie de antecedentes entre los que se contemplan informes, artículos y campañas de investigación y evaluación post-tsunami, realizados en el litoral afectado. Se establece una caracterización cualitativa y estadística de las pérdidas de vidas humanas, viviendas, infraestructura costera y embarcaciones, separando pérdidas asociadas al tsunami de aquellas atribuibles exclusivamente al sismo. Mediante este catastro que integra información proveniente de fuentes de diferente naturaleza, se espera contribuir a evaluar los daños asociados al tsunami. Abstract in english The Mw = 8.8 2010 Chile Earthquake is among the largest recorded by instruments to date, ranking as the second strongest in the country's history and one of the ten strongest worldwide. One of its main consequences was a destructive tsunami caused by the deformation of seafloor. The waves struck nea [...] rly 600 km of the coast of central Chile and the event caused about one third of the total casualties (181 out of 521), becoming the highest death toll due to this type of phenomena in South America in the last 30 years. In this paper the authors gather and systematize information from reports, papers and post-tsunami surveys carried out along the affected coastline. A qualitative and statistical characterization of the loss in lives, homes, infrastructure and fishing vessels is provided, separating tsunami effects to those attributable solely to the earthquake. Through the classification and integration of various data sources the authors expect to better explain and assess the damage specifically associated with the tsunami.
Manuel, Contreras; Patricio, Winckler.
The March 11, 2011 Tohoku-Oki tsunami triggered by an earthquake off the east coast of northeastern Honshu Island (Tohoku region), Japan, deposited large amounts of sediment on land, including the Sendai Plain and Sanriku Coast. This study reports on the characteristics of the tsunami deposits in Rikuzentakata City, southeastern Iwate Prefecture, northeastern Japan. A field survey identified the inundation pattern of the tsunami in this region and the facies model of the tsunami deposits at the bay-head deltas of estuarine systems. The tsunami deposits in Rikuzentakata City generally consist of one to four units that represent a discrete runup or backwash flow. Each unit is characterized by initial inverse grading and successive normal grading that correspond to the accelerating and decelerating stages of the flow, respectively. An internal erosional surface often developed between the inverse-graded and normal-graded units. It corresponds to the maximum shear velocity of the flow and truncates the underlying inverse-graded unit. In the case of the runup unit, silty fine-grained drapes overlay the graded sandy interval. A correlation of the sedimentary structures and grain fabric analysis revealed that the Tohoku-Oki tsunami inundated Rikuzentakata City at least twice and that the flow velocity exceeded 2.4 m/s. Paleontological analysis of the sediment and kriging estimation of the total volume of the tsunami deposit implied that the sediments were sourced not only from eroded beach sands but also from the seafloor of Hirota Bay or more offshore regions.
Naruse, Hajime; Arai, Kazuno; Matsumoto, Dan; Takahashi, Hiroki; Yamashita, Shota; Tanaka, Gengo; Murayama, Masafumi
The destructive Pacific Ocean tsunami generated off the east coast of Honshu, Japan, on 11 March 2011 prompted the West Coast and Alaska Tsunami Warning Center (WCATWC) to issue a tsunami warning and advisory for the coastal regions of Alaska, British Columbia, Washington, Oregon, and California. Estimating the length of time the warning or advisory would remain in effect proved difficult. To address this problem, the WCATWC developed a technique to estimate the amplitude decay of a tsunami recorded at tide stations within the Warning Center's Area of Responsibly (AOR). At many sites along the West Coast of North America, the tsunami wave amplitudes will decay exponentially following the arrival of the maximum wave ( Mofjeld et al., Nat Hazards 22:71-89, 2000). To estimate the time it will take before wave amplitudes drop to safe levels, the real-time tide gauge data are filtered to remove the effects of tidal variations. The analytic envelope is computed and a 2 h sequence of amplitude values following the tsunami peak is used to obtain a least squares fit to an exponential function. This yields a decay curve which is then combined with an average West Coast decay function to provide an initial tsunami amplitude-duration forecast. This information may then be provided to emergency managers to assist with response planning.
Nyland, David; Huang, Paul