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Sample records for tsunami generation models

  1. Tsunami Generation Modelling for Early Warning Systems

    NASA Astrophysics Data System (ADS)

    Annunziato, A.; Matias, L.; Ulutas, E.; Baptista, M. A.; Carrilho, F.

    2009-04-01

    In the frame of a collaboration between the European Commission Joint Research Centre and the Institute of Meteorology in Portugal, a complete analytical tool to support Early Warning Systems is being developed. The tool will be part of the Portuguese National Early Warning System and will be used also in the frame of the UNESCO North Atlantic Section of the Tsunami Early Warning System. The system called Tsunami Analysis Tool (TAT) includes a worldwide scenario database that has been pre-calculated using the SWAN-JRC code (Annunziato, 2007). This code uses a simplified fault generation mechanism and the hydraulic model is based on the SWAN code (Mader, 1988). In addition to the pre-defined scenario, a system of computers is always ready to start a new calculation whenever a new earthquake is detected by the seismic networks (such as USGS or EMSC) and is judged capable to generate a Tsunami. The calculation is performed using minimal parameters (epicentre and the magnitude of the earthquake): the programme calculates the rupture length and rupture width by using empirical relationship proposed by Ward (2002). The database calculations, as well the newly generated calculations with the current conditions are therefore available to TAT where the real online analysis is performed. The system allows to analyze also sea level measurements available worldwide in order to compare them and decide if a tsunami is really occurring or not. Although TAT, connected with the scenario database and the online calculation system, is at the moment the only software that can support the tsunami analysis on a global scale, we are convinced that the fault generation mechanism is too simplified to give a correct tsunami prediction. Furthermore short tsunami arrival times especially require a possible earthquake source parameters data on tectonic features of the faults like strike, dip, rake and slip in order to minimize real time uncertainty of rupture parameters. Indeed the earthquake

  2. Tsunamis: stochastic models of occurrence and generation mechanisms

    USGS Publications Warehouse

    Geist, Eric L.; Oglesby, David D.

    2014-01-01

    The devastating consequences of the 2004 Indian Ocean and 2011 Japan tsunamis have led to increased research into many different aspects of the tsunami phenomenon. In this entry, we review research related to the observed complexity and uncertainty associated with tsunami generation, propagation, and occurrence described and analyzed using a variety of stochastic methods. In each case, seismogenic tsunamis are primarily considered. Stochastic models are developed from the physical theories that govern tsunami evolution combined with empirical models fitted to seismic and tsunami observations, as well as tsunami catalogs. These stochastic methods are key to providing probabilistic forecasts and hazard assessments for tsunamis. The stochastic methods described here are similar to those described for earthquakes (Vere-Jones 2013) and volcanoes (Bebbington 2013) in this encyclopedia.

  3. Airburst-Generated Tsunamis

    NASA Astrophysics Data System (ADS)

    Berger, Marsha; Goodman, Jonathan

    2018-04-01

    This paper examines the questions of whether smaller asteroids that burst in the air over water can generate tsunamis that could pose a threat to distant locations. Such airburst-generated tsunamis are qualitatively different than the more frequently studied earthquake-generated tsunamis, and differ as well from tsunamis generated by asteroids that strike the ocean. Numerical simulations are presented using the shallow water equations in several settings, demonstrating very little tsunami threat from this scenario. A model problem with an explicit solution that demonstrates and explains the same phenomena found in the computations is analyzed. We discuss the question of whether compressibility and dispersion are important effects that should be included, and show results from a more sophisticated model problem using the linearized Euler equations that begins to addresses this.

  4. Modeling Tsunami Wave Generation Using a Two-layer Granular Landslide Model

    NASA Astrophysics Data System (ADS)

    Ma, G.; Kirby, J. T., Jr.; Shi, F.; Grilli, S. T.; Hsu, T. J.

    2016-12-01

    Tsunamis can be generated by subaerial or submarine landslides in reservoirs, lakes, fjords, bays and oceans. Compared to seismogenic tsunamis, landslide or submarine mass failure (SMF) tsunamis are normally characterized by relatively shorter wave lengths and stronger wave dispersion, and potentially may generate large wave amplitudes locally and high run-up along adjacent coastlines. Due to a complex interplay between the landslide and tsunami waves, accurate simulation of landslide motion as well as tsunami generation is a challenging task. We develop and test a new two-layer model for granular landslide motion and tsunami wave generation. The landslide is described as a saturated granular flow, accounting for intergranular stresses governed by Coulomb friction. Tsunami wave generation is simulated by the three-dimensional non-hydrostatic wave model NHWAVE, which is capable of capturing wave dispersion efficiently using a small number of discretized vertical levels. Depth-averaged governing equations for the granular landslide are derived in a slope-oriented coordinate system, taking into account the dynamic interaction between the lower-layer granular landslide and upper-layer water motion. The model is tested against laboratory experiments on impulsive wave generation by subaerial granular landslides. Model results illustrate a complex interplay between the granular landslide and tsunami waves, and they reasonably predict not only the tsunami wave generation but also the granular landslide motion from initiation to deposition.

  5. Observation and Modeling of Tsunami-Generated Gravity Waves in the Earth’s Upper Atmosphere

    DTIC Science & Technology

    2015-10-08

    Observation and modeling of tsunami -generated gravity waves in the earth’s upper atmosphere 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...ABSTRACT Build a compatible set of models which 1) calculate the spectrum of atmospheric GWs excited by a tsunami (using ocean model data as input...for public release; distribution is unlimited. Observation and modeling of tsunami -generated gravity waves in the earth’s upper atmosphere Sharon

  6. Landslide-Generated Tsunami Model for Quick Hazard Assessment

    NASA Astrophysics Data System (ADS)

    Franz, M.; Rudaz, B.; Locat, J.; Jaboyedoff, M.; Podladchikov, Y.

    2015-12-01

    Alpine regions are likely to be areas at risk regarding to landslide-induced tsunamis, because of the proximity between lakes and potential instabilities and due to the concentration of the population in valleys and on the lakes shores. In particular, dam lakes are often surrounded by steep slopes and frequently affect the stability of the banks. In order to assess comprehensively this phenomenon together with the induced risks, we have developed a 2.5D numerical model which aims to simulate the propagation of the landslide, the generation and the propagation of the wave and eventually the spread on the shores or the associated downstream flow. To perform this task, the process is done in three steps. Firstly, the geometry of the sliding mass is constructed using the Sloping Local Base Level (SLBL) concept. Secondly, the propagation of this volume is performed using a model based on viscous flow equations. Finally, the wave generation and its propagation are simulated using the shallow water equations stabilized by the Lax-Friedrichs scheme. The transition between wet and dry bed is performed by the combination of the two latter sets of equations. The proper behavior of our model is demonstrated by; (1) numerical tests from Toro (2001), and (2) by comparison with a real event where the horizontal run-up distance is known (Nicolet landslide, Quebec, Canada). The model is of particular interest due to its ability to perform quickly the 2.5D geometric model of the landslide, the tsunami simulation and, consequently, the hazard assessment.

  7. Issues and Advances in Understanding Landslide-Generated Tsunamis: Toward a Unified Model

    NASA Astrophysics Data System (ADS)

    Geist, E. L.; Locat, J.; Lee, H. J.; Lynett, P. J.; Parsons, T.; Kayen, R. E.; Hart, P. E.

    2008-12-01

    The physics of tsunamis generated from submarine landslides is highly complex, involving a cross- disciplinary exchange in geophysics. In the 10 years following the devastating Papua New Guinea tsunami, there have been significant advances in understanding landslide-generated tsunamis. However, persistent issues still remain related to submarine landslide dynamics that may be addressed with collection of new marine geologic and geophysical observations. We review critical elements of landslide tsunamis in the hope of developing a unified model that encompasses all stages of the process from triggering to tsunami runup. Because the majority of non-volcanogenic landslides that generate tsunamis are triggered seismically, advances in understanding inertial displacements and changes in strength and rheologic properties in response to strong-ground motion need to be included in a unified model. For example, interaction between compliant marine sediments and multi-direction ground motion results in greater permanent plastic displacements than predicted by traditional rigid-block analysis. When considering the coupling of the overlying water layer in the generation of tsunamis, the post-failure dynamics of landslides is important since the overall rate of seafloor deformation for landslides is less than or comparable to the phase speed of tsunami waves. As such, the rheologic and mechanical behavior of the slide material needs to be well understood. For clayey and silty debris flows, a non-linear (Herschel-Bulkley) and bilinear rheology have recently been developed to explain observed runout distances and deposit thicknesses. An additional complexity to this rheology is the inclusion of hydrate-laden sediment that commonly occurs along continental slopes. Although it has been proposed in the past that gas hydrate dissociation may provide potential failure planes for slide movement, it is unclear how zones of rigid hydrate-bearing sediment surrounded by a more viscoplastic

  8. Numerical Modelling of Tsunami Generated by Deformable Submarine Slides: Parameterisation of Slide Dynamics for Coupling to Tsunami Propagation Model

    NASA Astrophysics Data System (ADS)

    Smith, R. C.; Collins, G. S.; Hill, J.; Piggott, M. D.; Mouradian, S. L.

    2015-12-01

    Numerical modelling informs risk assessment of tsunami generated by submarine slides; however, for large-scale slides modelling can be complex and computationally challenging. Many previous numerical studies have approximated slides as rigid blocks that moved according to prescribed motion. However, wave characteristics are strongly dependent on the motion of the slide and previous work has recommended that more accurate representation of slide dynamics is needed. We have used the finite-element, adaptive-mesh CFD model Fluidity, to perform multi-material simulations of deformable submarine slide-generated waves at real world scales for a 2D scenario in the Gulf of Mexico. Our high-resolution approach represents slide dynamics with good accuracy, compared to other numerical simulations of this scenario, but precludes tracking of wave propagation over large distances. To enable efficient modelling of further propagation of the waves, we investigate an approach to extract information about the slide evolution from our multi-material simulations in order to drive a single-layer wave propagation model, also using Fluidity, which is much less computationally expensive. The extracted submarine slide geometry and position as a function of time are parameterised using simple polynomial functions. The polynomial functions are used to inform a prescribed velocity boundary condition in a single-layer simulation, mimicking the effect the submarine slide motion has on the water column. The approach is verified by successful comparison of wave generation in the single-layer model with that recorded in the multi-material, multi-layer simulations. We then extend this approach to 3D for further validation of this methodology (using the Gulf of Mexico scenario proposed by Horrillo et al., 2013) and to consider the effect of lateral spreading. This methodology is then used to simulate a series of hypothetical submarine slide events in the Arctic Ocean (based on evidence of historic

  9. Modeling for the SAFRR Tsunami Scenario-generation, propagation, inundation, and currents in ports and harbors: Chapter D in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    USGS Publications Warehouse

    ,

    2013-01-01

    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

  10. Tsunami Casualty Model

    NASA Astrophysics Data System (ADS)

    Yeh, H.

    2007-12-01

    More than 4500 deaths by tsunamis were recorded in the decade of 1990. For example, the 1992 Flores Tsunami in Indonesia took away at least 1712 lives, and more than 2182 people were victimized by the 1998 Papua New Guinea Tsunami. Such staggering death toll has been totally overshadowed by the 2004 Indian Ocean Tsunami that claimed more than 220,000 lives. Unlike hurricanes that are often evaluated by economic losses, death count is the primary measure for tsunami hazard. It is partly because tsunamis kill more people owing to its short lead- time for warning. Although exact death tallies are not available for most of the tsunami events, there exist gender and age discriminations in tsunami casualties. Significant gender difference in the victims of the 2004 Indian Ocean Tsunami was attributed to women's social norms and role behavior, as well as cultural bias toward women's inability to swim. Here we develop a rational casualty model based on humans' limit to withstand the tsunami flows. The application to simple tsunami runup cases demonstrates that biological and physiological disadvantages also make a significant difference in casualty rate. It further demonstrates that the gender and age discriminations in casualties become most pronounced when tsunami is marginally strong and the difference tends to diminish as tsunami strength increases.

  11. Landslide-generated tsunamis in a perialpine lake: Historical events and numerical models

    NASA Astrophysics Data System (ADS)

    Hilbe, Michael; Anselmetti, Flavio S.

    2014-05-01

    Many of the perialpine lakes in Central Europe - the large, glacier-carved basins formed during the Pleistocene glaciations of the Alps - have proven to be environments prone to subaquatic landsliding. Among these, Lake Lucerne (Switzerland) has a particularly well-established record of subaquatic landslides and related tsunamis. Its sedimentary archive documents numerous landslides over the entire Holocene, which have either been triggered by earthquakes, or which occurred apparently spontaneously, possibly due to rapid sediment accumulation on delta slopes. Due to their controlled boundary conditions and the possibility to be investigated on a complete basinal scale, such lacustrine tsunamis may be used as textbook analogons for their marine counterparts. Two events in the 17th century illustrate these processes and their consequences: In AD 1601, an earthquake (Mw ~ 5.9) led to widespread failure of the sediment drape covering the lateral slopes in several basins. The resulting landslides generated tsunami waves that reached a runup of several metres, as reported in historical accounts. The waves caused widespread damage as well as loss of lives in communities along the shores. In AD 1687, the apparently spontaneous collapse of a river delta in the lake led to similar waves that damaged nearby villages. Based on detailed information on topography, bathymetry and the geometry of the landslide deposits, numerical simulations combining two-dimensional, depth-averaged models for landslide propagation, as well as for tsunami generation, propagation and inundation, are able to reproduce most of the reported tsunami effects for these events. Calculated maximum runup of the waves is 6 to >10 m in the directly affected lake basins, but significantly less in neighbouring basins. Flat alluvial plains adjacent to the most heavily affected areas are inundated over distances of several hundred metres. Taken as scenarios for possible future events, these past events suggest

  12. Seismically generated tsunamis.

    PubMed

    Arcas, Diego; Segur, Harvey

    2012-04-13

    People around the world know more about tsunamis than they did 10 years ago, primarily because of two events: a tsunami on 26 December 2004 that killed more than 200,000 people around the shores of the Indian Ocean; and an earthquake and tsunami off the coast of Japan on 11 March 2011 that killed nearly 15,000 more and triggered a nuclear accident, with consequences that are still unfolding. This paper has three objectives: (i) to summarize our current knowledge of the dynamics of tsunamis; (ii) to describe how that knowledge is now being used to forecast tsunamis; and (iii) to suggest some policy changes that might protect people better from the dangers of future tsunamis.

  13. Benchmarking Multilayer-HySEA model for landslide generated tsunami. HTHMP validation process.

    NASA Astrophysics Data System (ADS)

    Macias, J.; Escalante, C.; Castro, M. J.

    2017-12-01

    Landslide tsunami hazard may be dominant along significant parts of the coastline around the world, in particular in the USA, as compared to hazards from other tsunamigenic sources. This fact motivated NTHMP about the need of benchmarking models for landslide generated tsunamis, following the same methodology already used for standard tsunami models when the source is seismic. To perform the above-mentioned validation process, a set of candidate benchmarks were proposed. These benchmarks are based on a subset of available laboratory data sets for solid slide experiments and deformable slide experiments, and include both submarine and subaerial slides. A benchmark based on a historic field event (Valdez, AK, 1964) close the list of proposed benchmarks. A total of 7 benchmarks. The Multilayer-HySEA model including non-hydrostatic effects has been used to perform all the benchmarking problems dealing with laboratory experiments proposed in the workshop that was organized at Texas A&M University - Galveston, on January 9-11, 2017 by NTHMP. The aim of this presentation is to show some of the latest numerical results obtained with the Multilayer-HySEA (non-hydrostatic) model in the framework of this validation effort.Acknowledgements. This research has been partially supported by the Spanish Government Research project SIMURISK (MTM2015-70490-C02-01-R) and University of Malaga, Campus de Excelencia Internacional Andalucía Tech. The GPU computations were performed at the Unit of Numerical Methods (University of Malaga).

  14. Physical modelling of tsunamis generated by three-dimensional deformable granular landslides on planar and conical island slopes

    PubMed Central

    2016-01-01

    Tsunamis generated by landslides and volcanic island collapses account for some of the most catastrophic events recorded, yet critically important field data related to the landslide motion and tsunami evolution remain lacking. Landslide-generated tsunami source and propagation scenarios are physically modelled in a three-dimensional tsunami wave basin. A unique pneumatic landslide tsunami generator was deployed to simulate landslides with varying geometry and kinematics. The landslides were generated on a planar hill slope and divergent convex conical hill slope to study lateral hill slope effects on the wave characteristics. The leading wave crest amplitude generated on a planar hill slope is larger on average than the leading wave crest generated on a convex conical hill slope, whereas the leading wave trough and second wave crest amplitudes are smaller. Between 1% and 24% of the landslide kinetic energy is transferred into the wave train. Cobble landslides transfer on average 43% more kinetic energy into the wave train than corresponding gravel landslides. Predictive equations for the offshore propagating wave amplitudes, periods, celerities and lengths generated by landslides on planar and divergent convex conical hill slopes are derived, which allow an initial rapid tsunami hazard assessment. PMID:27274697

  15. Physical modelling of tsunamis generated by three-dimensional deformable granular landslides on planar and conical island slopes.

    PubMed

    McFall, Brian C; Fritz, Hermann M

    2016-04-01

    Tsunamis generated by landslides and volcanic island collapses account for some of the most catastrophic events recorded, yet critically important field data related to the landslide motion and tsunami evolution remain lacking. Landslide-generated tsunami source and propagation scenarios are physically modelled in a three-dimensional tsunami wave basin. A unique pneumatic landslide tsunami generator was deployed to simulate landslides with varying geometry and kinematics. The landslides were generated on a planar hill slope and divergent convex conical hill slope to study lateral hill slope effects on the wave characteristics. The leading wave crest amplitude generated on a planar hill slope is larger on average than the leading wave crest generated on a convex conical hill slope, whereas the leading wave trough and second wave crest amplitudes are smaller. Between 1% and 24% of the landslide kinetic energy is transferred into the wave train. Cobble landslides transfer on average 43% more kinetic energy into the wave train than corresponding gravel landslides. Predictive equations for the offshore propagating wave amplitudes, periods, celerities and lengths generated by landslides on planar and divergent convex conical hill slopes are derived, which allow an initial rapid tsunami hazard assessment.

  16. Tsunami: ocean dynamo generator.

    PubMed

    Sugioka, Hiroko; Hamano, Yozo; Baba, Kiyoshi; Kasaya, Takafumi; Tada, Noriko; Suetsugu, Daisuke

    2014-01-08

    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.

  17. Physical Modeling of Landslide Generated Tsunamis and the 50th Anniversary of the Vajont Dam Disaster

    NASA Astrophysics Data System (ADS)

    McFall, Brian C.; Mohammed, Fahad; Fritz, Hermann M.

    2013-04-01

    The Vajont river is an affluent of the Piave River located in the Dolomite Alps of the Veneto Region, about 100km north of Venice. A 265.5 m high double curved arch dam was built across a V-shaped gorge creating a reservoir with a maximum storage capacity of 0.169 km3. A maximum water depth of 250 m was reached by early September 1963 during the third filling attempt of the reservoir, but as creeping on the southern flank increased the third reservoir draw down was initiated. By October 9, 1963 the water depth was lowered to 240m as the southern flank of Vajont reservoir catastrophically collapsed on a length of more than 2km. Collapse occurred during reservoir drawdown in a final attempt to reduce flank creeping and the reservoir was only about two-thirds full. The partially submerged rockslide with a volume of 0.24 km3 penetrated into the reservoir at velocities up to 30 m/s. The wave runup in direct prolongation of slide axis reached the lowest houses of Casso 270m above reservoir level before impact corresponding to 245m above dam crest (Müller, 1964). The rockslide deposit came within 50m of the left abutment and towers up to 140m above the dam crest. The lateral spreading of the surge overtopped the dam crest by more than 100m. The thin arch dam withstood the overtopping and sustained no damage to the structural shell and the abutments. The flood wave dropped more than 500m down the Vajont gorge and into the Piave Valley causing utter destruction to the villages of Longarone, Pirago, Villanova, Rivalta and Fae. More than 2000 persons perished. The Vajont disaster highlights an extreme landslide tsunami event in the narrowly confined water body of a reservoir. Landslide tsunami hazards exist even in areas not exposed to tectonic tsunamis. Source and runup scenarios based on real world events are physically modeled in the three dimensional NEES tsunami wave basin (TWB) at Oregon State University (OSU). A novel pneumatic landslide tsunami generator (LTG) was

  18. Signals in the ionosphere generated by tsunami earthquakes: observations and modeling suppor

    NASA Astrophysics Data System (ADS)

    Rolland, L.; Sladen, A.; Mikesell, D.; Larmat, C. S.; Rakoto, V.; Remillieux, M.; Lee, R.; Khelfi, K.; Lognonne, P. H.; Astafyeva, E.

    2017-12-01

    Forecasting systems failed to predict the magnitude of the 2011 great tsunami in Japan due to the difficulty and cost of instrumenting the ocean with high-quality and dense networks. Melgar et al. (2013) show that using all of the conventional data (inland seismic, geodetic, and tsunami gauges) with the best inversion method still fails to predict the correct height of the tsunami before it breaks onto a coast near the epicenter (< 500 km). On the other hand, in the last decade, scientists have gathered convincing evidence of transient signals in the ionosphere Total Electron Content (TEC) observations that are associated to open ocean tsunami waves. Even though typical tsunami waves are only a few centimeters high, they are powerful enough to create atmospheric vibrations extending all the way to the ionosphere, 300 kilometers up in the atmosphere. Therefore, we are proposing to incorporate the ionospheric signals into tsunami early-warning systems. We anticipate that the method could be decisive for mitigating "tsunami earthquakes" which trigger tsunamis larger than expected from their short-period magnitude. These events are challenging to characterize as they rupture the near-trench subduction interface, in a distant region less constrained by onshore data. As a couple of devastating tsunami earthquakes happens per decade, they represent a real threat for onshore populations and a challenge for tsunami early-warning systems. We will present the TEC observations of the recent Java 2006 and Mentawaii 2010 tsunami earthquakes and base our analysis on acoustic ray tracing, normal modes summation and the simulation code SPECFEM, which solves the wave equation in coupled acoustic (ocean, atmosphere) and elastic (solid earth) domains. Rupture histories are entered as finite source models, which will allow us to evaluate the effect of a relatively slow rupture on the surrounding ocean and atmosphere.

  19. A Hybrid Tsunami Risk Model for Japan

    NASA Astrophysics Data System (ADS)

    Haseemkunju, A. V.; Smith, D. F.; Khater, M.; Khemici, O.; Betov, B.; Scott, J.

    2014-12-01

    Around the margins of the Pacific Ocean, denser oceanic plates slipping under continental plates cause subduction earthquakes generating large tsunami waves. The subducting Pacific and Philippine Sea plates create damaging interplate earthquakes followed by huge tsunami waves. It was a rupture of the Japan Trench subduction zone (JTSZ) and the resultant M9.0 Tohoku-Oki earthquake that caused the unprecedented tsunami along the Pacific coast of Japan on March 11, 2011. EQECAT's Japan Earthquake model is a fully probabilistic model which includes a seismo-tectonic model describing the geometries, magnitudes, and frequencies of all potential earthquake events; a ground motion model; and a tsunami model. Within the much larger set of all modeled earthquake events, fault rupture parameters for about 24000 stochastic and 25 historical tsunamigenic earthquake events are defined to simulate tsunami footprints using the numerical tsunami model COMCOT. A hybrid approach using COMCOT simulated tsunami waves is used to generate inundation footprints, including the impact of tides and flood defenses. Modeled tsunami waves of major historical events are validated against observed data. Modeled tsunami flood depths on 30 m grids together with tsunami vulnerability and financial models are then used to estimate insured loss in Japan from the 2011 tsunami. The primary direct report of damage from the 2011 tsunami is in terms of the number of buildings damaged by municipality in the tsunami affected area. Modeled loss in Japan from the 2011 tsunami is proportional to the number of buildings damaged. A 1000-year return period map of tsunami waves shows high hazard along the west coast of southern Honshu, on the Pacific coast of Shikoku, and on the east coast of Kyushu, primarily associated with major earthquake events on the Nankai Trough subduction zone (NTSZ). The highest tsunami hazard of more than 20m is seen on the Sanriku coast in northern Honshu, associated with the JTSZ.

  20. Numerical modeling of landslide-generated tsunami using adaptive unstructured meshes

    NASA Astrophysics Data System (ADS)

    Wilson, Cian; Collins, Gareth; Desousa Costa, Patrick; Piggott, Matthew

    2010-05-01

    Landslides impacting into or occurring under water generate waves, which can have devastating environmental consequences. Depending on the characteristics of the landslide the waves can have significant amplitude and potentially propagate over large distances. Linear models of classical earthquake-generated tsunamis cannot reproduce the highly nonlinear generation mechanisms required to accurately predict the consequences of landslide-generated tsunamis. Also, laboratory-scale experimental investigation is limited to simple geometries and short time-scales before wave reflections contaminate the data. Computational fluid dynamics models based on the nonlinear Navier-Stokes equations can simulate landslide-tsunami generation at realistic scales. However, traditional chessboard-like structured meshes introduce superfluous resolution and hence the computing power required for such a simulation can be prohibitively high, especially in three dimensions. Unstructured meshes allow the grid spacing to vary rapidly from high resolution in the vicinity of small scale features to much coarser, lower resolution in other areas. Combining this variable resolution with dynamic mesh adaptivity allows such high resolution zones to follow features like the interface between the landslide and the water whilst minimising the computational costs. Unstructured meshes are also better suited to representing complex geometries and bathymetries allowing more realistic domains to be simulated. Modelling multiple materials, like water, air and a landslide, on an unstructured adaptive mesh poses significant numerical challenges. Novel methods of interface preservation must be considered and coupled to a flow model in such a way that ensures conservation of the different materials. Furthermore this conservation property must be maintained during successive stages of mesh optimisation and interpolation. In this paper we validate a new multi-material adaptive unstructured fluid dynamics model

  1. A computationally fast, reduced model for simulating landslide dynamics and tsunamis generated by landslides in natural terrains

    NASA Astrophysics Data System (ADS)

    Mohammed, F.

    2016-12-01

    Landslide hazards such as fast-moving debris flows, slow-moving landslides, and other mass flows cause numerous fatalities, injuries, and damage. Landslide occurrences in fjords, bays, and lakes can additionally generate tsunamis with locally extremely high wave heights and runups. Two-dimensional depth-averaged models can successfully simulate the entire lifecycle of the three-dimensional landslide dynamics and tsunami propagation efficiently and accurately with the appropriate assumptions. Landslide rheology is defined using viscous fluids, visco-plastic fluids, and granular material to account for the possible landslide source materials. Saturated and unsaturated rheologies are further included to simulate debris flow, debris avalanches, mudflows, and rockslides respectively. The models are obtained by reducing the fully three-dimensional Navier-Stokes equations with the internal rheological definition of the landslide material, the water body, and appropriate scaling assumptions to obtain the depth-averaged two-dimensional models. The landslide and tsunami models are coupled to include the interaction between the landslide and the water body for tsunami generation. The reduced models are solved numerically with a fast semi-implicit finite-volume, shock-capturing based algorithm. The well-balanced, positivity preserving algorithm accurately accounts for wet-dry interface transition for the landslide runout, landslide-water body interface, and the tsunami wave flooding on land. The models are implemented as a General-Purpose computing on Graphics Processing Unit-based (GPGPU) suite of models, either coupled or run independently within the suite. The GPGPU implementation provides up to 1000 times speedup over a CPU-based serial computation. This enables simulations of multiple scenarios of hazard realizations that provides a basis for a probabilistic hazard assessment. The models have been successfully validated against experiments, past studies, and field data

  2. Asteroid-Generated Tsunami and Impact Risk

    NASA Astrophysics Data System (ADS)

    Boslough, M.; Aftosmis, M.; Berger, M. J.; Ezzedine, S. M.; Gisler, G.; Jennings, B.; LeVeque, R. J.; Mathias, D.; McCoy, C.; Robertson, D.; Titov, V. V.; Wheeler, L.

    2016-12-01

    The justification for planetary defense comes from a cost/benefit analysis, which includes risk assessment. The contribution from ocean impacts and airbursts is difficult to quantify and represents a significant uncertainty in our assessment of the overall risk. Our group is currently working toward improved understanding of impact scenarios that can generate dangerous tsunami. The importance of asteroid-generated tsunami research has increased because a new Science Definition Team, at the behest of NASA's Planetary Defense Coordinating Office, is now updating the results of a 2003 study on which our current planetary defense policy is based Our group was formed to address this question on many fronts, including asteroid entry modeling, tsunami generation and propagation simulations, modeling of coastal run-ups, inundation, and consequences, infrastructure damage estimates, and physics-based probabilistic impact risk assessment. We also organized the Second International Workshop on Asteroid Threat Assessment, focused on asteroid-generated tsunami and associated risk (Aug. 23-24, 2016). We will summarize our progress and present the highlights of our workshop, emphasizing its relevance to earth and planetary science. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

  3. Alternative Tsunami Models

    ERIC Educational Resources Information Center

    Tan, A.; Lyatskaya, I.

    2009-01-01

    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,…

  4. Physical Modeling of Tsunamis Generated By 3D Deformable Landslides in Various Scenarios From Fjords to Conical Islands

    NASA Astrophysics Data System (ADS)

    McFall, B. C.; Fritz, H. M.

    2013-12-01

    Tsunamis generated by landslides and volcano flank collapse can be particularly devastative in the near field region due to locally high wave amplitudes and runup. The events of 1958 Lituya Bay, 1963 Vajont reservoir, 1980 Spirit Lake, 2002 Stromboli and 2010 Haiti demonstrate the danger of tsunamis generated by landslides or volcano flank collapses. Unfortunately critical field data from these events is lacking. Source and runup scenarios based on real world events are physically modeled using generalized Froude similarity in the three dimensional NEES tsunami wave basin at Oregon State University. A novel pneumatic landslide tsunami generator (LTG) was deployed to simulate landslides with varying geometry and kinematics. Two different materials are used to simulate landslides to study the granulometry effects: naturally rounded river gravel and cobble mixtures. The LTG consists of a sliding box filled with 1,350 kg of landslide material which is accelerated by means of four pneumatic pistons down a 2H:1V slope. The landslide is launched from the sliding box and continues to accelerate by gravitational forces up to velocities of 5 m/s. The landslide Froude number at impact with the water is in the range 1

  5. Peru 2007 tsunami runup observations and modeling

    NASA Astrophysics Data System (ADS)

    Fritz, H. M.; Kalligeris, N.; Borrero, J. C.

    2008-05-01

    On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a tsunami with locally focused runup heights of up to 10 m. A reconnaissance team was deployed in the immediate aftermath and investigated the tsunami effects at 51 sites. The largest runup heights were measured in a sparsely populated desert area south of the Paracas Peninsula resulting in only 3 tsunami fatalities. Numerical modeling of the earthquake source and tsunami suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the presence of the Paracas Peninsula, which blocked tsunami waves from propagating northward from the high slip region. The coast of Peru has experienced numerous deadly and destructive tsunamis throughout history, which highlights the importance of ongoing tsunami awareness and education efforts in the region. The Peru tsunami is compared against recent mega-disasters such as the 2004 Indian Ocean tsunami and Hurricane Katrina.

  6. Combining SLBL routine with landslide-generated tsunami model for a quick hazard assessment tool

    NASA Astrophysics Data System (ADS)

    Franz, Martin; Rudaz, Benjamin; Jaboyedoff, Michel; Podladchikov, Yury

    2016-04-01

    Regions with steep topography are potentially subject to landslide-induced tsunami, because of the proximity between lakes, rivers, sea shores and potential instabilities. The concentration of the population and infrastructures on the water body shores and downstream valleys could lead to catastrophic consequences. In order to assess comprehensively this phenomenon together with the induced risks, we have developed a tool which allows the construction of the landslide geometry, and which is able to simulate its propagation, the generation and the propagation of the wave and eventually the spread on the shores or the associated downstream flow. The tool is developed in the Matlab© environment, with a graphical user interface (GUI) to select the parameters in a user-friendly manner. The whole process is done in three steps implying different methods. Firstly, the geometry of the sliding mass is constructed using the Sloping Local Base Level (SLBL) concept. Secondly, the propagation of this volume is performed using a model based on viscous flow equations. Finally, the wave generation and its propagation are simulated using the shallow water equations stabilized by the Lax-Friedrichs scheme. The transition between wet and dry bed is performed by the combination of the two latter sets of equations. The intensity map is based on the criterion of flooding in Switzerland provided by the OFEG and results from the multiplication of the velocity and the depth obtained during the simulation. The tool can be used for hazard assessment in the case of well-known landslides, where the SLBL routine can be constrained and checked for realistic construction of the geometrical model. In less-known cases, various failure plane geometries can be automatically built between given range and thus a multi-scenario approach is used. In any case, less-known parameters such as the landslide velocity, its run-out distance, etc. can also be set to vary within given ranges, leading to multi

  7. Impact of a Cosmic Body into Earth's Ocean and the Generation of Large Tsunami Waves: Insight from Numerical Modeling

    NASA Astrophysics Data System (ADS)

    Wünnemann, K.; Collins, G. S.; Weiss, R.

    2010-12-01

    The strike of a cosmic body into a marine environment differs in several respects from impact on land. Oceans cover approximately 70% of the Earth's surface, implying not only that oceanic impact is a very likely scenario for future impacts but also that most impacts in Earth's history must have happened in marine environments. Therefore, the study of oceanic impact is imperative in two respects: (1) to quantify the hazard posed by future oceanic impacts, including the potential threat of large impact-generated tsunami-like waves, and (2) to reconstruct Earth's impact record by accounting for the large number of potentially undiscovered crater structures in the ocean crust. Reconstruction of the impact record is of crucial importance both for assessing the frequency of collision events in the past and for better predicting the probability of future impact. We summarize the advances in the study of oceanic impact over the last decades and focus in particular on how numerical models have improved our understanding of cratering in the oceanic environment and the generation of waves by impact. We focus on insight gleaned from numerical modeling studies into the deceleration of the projectile by the water, cratering of the ocean floor, the late stage modification of the crater due to gravitational collapse, and water resurge. Furthermore, we discuss the generation and propagation of large tsunami-like waves as a result of a strike of a cosmic body in marine environments.

  8. Modeling tsunamis induced by retrogressive submarine landslides

    NASA Astrophysics Data System (ADS)

    Løvholt, F.; Kim, J.; Harbitz, C. B.

    2015-12-01

    Enormous submarine landslides having volumes up to thousands of km3 and long run-out may cause tsunamis with widespread effects. Clay-rich landslides, such as Trænadjupet and Storegga offshore Norway commonly involve retrogressive mass and momentum release mechanisms that affect the tsunami generation. Therefore, such landslides may involve a large amount of smaller blocks. As a consequence, the failure mechanisms and release rate of the individual blocks are of importance for the tsunami generation. Previous attempts to model the tsunami generation due to retrogressive landslides are few, and limited to idealized conditions. Here, we review the basic effects of retrogression on tsunamigenesis in simple geometries. To this end, two different methods are employed for the landslide motion, a series block with pre-scribed time lags and kinematics, and a dynamic retrogressive model where the inter-block time lag is determined by the model. The effect of parameters such as time lag on wave-height, wave-length, and dispersion are discussed. Finally, we discuss how the retrogressive effects may have influenced the tsunamis due to large landslides such as the Storegga slide. The research leading to these results has received funding from the Research Council of Norway under grant number 231252 (Project TsunamiLand) and the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement 603839 (Project ASTARTE).

  9. The Global Tsunami Model (GTM)

    NASA Astrophysics Data System (ADS)

    Lorito, S.; Basili, R.; Harbitz, C. B.; Løvholt, F.; Polet, J.; Thio, H. K.

    2017-12-01

    The tsunamis occurred worldwide in the last two decades have highlighted the need for a thorough understanding of the risk posed by relatively infrequent but often disastrous tsunamis and the importance of a comprehensive and consistent methodology for quantifying the hazard. In the last few years, several methods for probabilistic tsunami hazard analysis have been developed and applied to different parts of the world. In an effort to coordinate and streamline these activities and make progress towards implementing the Sendai Framework of Disaster Risk Reduction (SFDRR) we have initiated a Global Tsunami Model (GTM) working group with the aim of i) enhancing our understanding of tsunami hazard and risk on a global scale and developing standards and guidelines for it, ii) providing a portfolio of validated tools for probabilistic tsunami hazard and risk assessment at a range of scales, and iii) developing a global tsunami hazard reference model. This GTM initiative has grown out of the tsunami component of the Global Assessment of Risk (GAR15), which has resulted in an initial global model of probabilistic tsunami hazard and risk. Started as an informal gathering of scientists interested in advancing tsunami hazard analysis, the GTM is currently in the process of being formalized through letters of interest from participating institutions. The initiative has now been endorsed by the United Nations International Strategy for Disaster Reduction (UNISDR) and the World Bank's Global Facility for Disaster Reduction and Recovery (GFDRR). We will provide an update on the state of the project and the overall technical framework, and discuss the technical issues that are currently being addressed, including earthquake source recurrence models, the use of aleatory variability and epistemic uncertainty, and preliminary results for a probabilistic global hazard assessment, which is an update of the model included in UNISDR GAR15.

  10. The Global Tsunami Model (GTM)

    NASA Astrophysics Data System (ADS)

    Løvholt, Finn

    2017-04-01

    The large tsunami disasters of the last two decades have highlighted the need for a thorough understanding of the risk posed by relatively infrequent but disastrous tsunamis and the importance of a comprehensive and consistent methodology for quantifying the hazard. In the last few years, several methods for probabilistic tsunami hazard analysis have been developed and applied to different parts of the world. In an effort to coordinate and streamline these activities and make progress towards implementing the Sendai Framework of Disaster Risk Reduction (SFDRR) we have initiated a Global Tsunami Model (GTM) working group with the aim of i) enhancing our understanding of tsunami hazard and risk on a global scale and developing standards and guidelines for it, ii) providing a portfolio of validated tools for probabilistic tsunami hazard and risk assessment at a range of scales, and iii) developing a global tsunami hazard reference model. This GTM initiative has grown out of the tsunami component of the Global Assessment of Risk (GAR15), which has resulted in an initial global model of probabilistic tsunami hazard and risk. Started as an informal gathering of scientists interested in advancing tsunami hazard analysis, the GTM is currently in the process of being formalized through letters of interest from participating institutions. The initiative has now been endorsed by the United Nations International Strategy for Disaster Reduction (UNISDR) and the World Bank's Global Facility for Disaster Reduction and Recovery (GFDRR). We will provide an update on the state of the project and the overall technical framework, and discuss the technical issues that are currently being addressed, including earthquake source recurrence models, the use of aleatory variability and epistemic uncertainty, and preliminary results for a probabilistic global hazard assessment, which is an update of the model included in UNISDR GAR15.

  11. The Global Tsunami Model (GTM)

    NASA Astrophysics Data System (ADS)

    Thio, H. K.; Løvholt, F.; Harbitz, C. B.; Polet, J.; Lorito, S.; Basili, R.; Volpe, M.; Romano, F.; Selva, J.; Piatanesi, A.; Davies, G.; Griffin, J.; Baptista, M. A.; Omira, R.; Babeyko, A. Y.; Power, W. L.; Salgado Gálvez, M.; Behrens, J.; Yalciner, A. C.; Kanoglu, U.; Pekcan, O.; Ross, S.; Parsons, T.; LeVeque, R. J.; Gonzalez, F. I.; Paris, R.; Shäfer, A.; Canals, M.; Fraser, S. A.; Wei, Y.; Weiss, R.; Zaniboni, F.; Papadopoulos, G. A.; Didenkulova, I.; Necmioglu, O.; Suppasri, A.; Lynett, P. J.; Mokhtari, M.; Sørensen, M.; von Hillebrandt-Andrade, C.; Aguirre Ayerbe, I.; Aniel-Quiroga, Í.; Guillas, S.; Macias, J.

    2016-12-01

    The large tsunami disasters of the last two decades have highlighted the need for a thorough understanding of the risk posed by relatively infrequent but disastrous tsunamis and the importance of a comprehensive and consistent methodology for quantifying the hazard. In the last few years, several methods for probabilistic tsunami hazard analysis have been developed and applied to different parts of the world. In an effort to coordinate and streamline these activities and make progress towards implementing the Sendai Framework of Disaster Risk Reduction (SFDRR) we have initiated a Global Tsunami Model (GTM) working group with the aim of i) enhancing our understanding of tsunami hazard and risk on a global scale and developing standards and guidelines for it, ii) providing a portfolio of validated tools for probabilistic tsunami hazard and risk assessment at a range of scales, and iii) developing a global tsunami hazard reference model. This GTM initiative has grown out of the tsunami component of the Global Assessment of Risk (GAR15), which has resulted in an initial global model of probabilistic tsunami hazard and risk. Started as an informal gathering of scientists interested in advancing tsunami hazard analysis, the GTM is currently in the process of being formalized through letters of interest from participating institutions. The initiative has now been endorsed by the United Nations International Strategy for Disaster Reduction (UNISDR) and the World Bank's Global Facility for Disaster Reduction and Recovery (GFDRR). We will provide an update on the state of the project and the overall technical framework, and discuss the technical issues that are currently being addressed, including earthquake source recurrence models, the use of aleatory variability and epistemic uncertainty, and preliminary results for a probabilistic global hazard assessment, which is an update of the model included in UNISDR GAR15.

  12. The 15 August 2007 Peru tsunami runup observations and modeling

    NASA Astrophysics Data System (ADS)

    Fritz, Hermann M.; Kalligeris, Nikos; Borrero, Jose C.; Broncano, Pablo; Ortega, Erick

    2008-05-01

    On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a tsunami with locally focused runup heights of up to10 m. A reconnaissance team was deployed two weeks after the event and investigated the tsunami effects at 51 sites. Three tsunami fatalities were reported south of the Paracas Peninsula in a sparsely populated desert area where the largest tsunami runup heights were measured. Numerical modeling of the earthquake source and tsunami suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the Paracas Peninsula, which blocked tsunami waves from propagating northward from the high slip region. The coast of Peru has experienced numerous deadly and destructive tsunamis throughout history, which highlights the importance of ongoing tsunami awareness and education efforts to ensure successful self-evacuation.

  13. Uncertainty in tsunami sediment transport modeling

    USGS Publications Warehouse

    Jaffe, Bruce E.; Goto, Kazuhisa; Sugawara, Daisuke; Gelfenbaum, Guy R.; La Selle, SeanPaul M.

    2016-01-01

    Erosion and deposition from tsunamis record information about tsunami hydrodynamics and size that can be interpreted to improve tsunami hazard assessment. We explore sources and methods for quantifying uncertainty in tsunami sediment transport modeling. Uncertainty varies with tsunami, study site, available input data, sediment grain size, and model. Although uncertainty has the potential to be large, published case studies indicate that both forward and inverse tsunami sediment transport models perform well enough to be useful for deciphering tsunami characteristics, including size, from deposits. New techniques for quantifying uncertainty, such as Ensemble Kalman Filtering inversion, and more rigorous reporting of uncertainties will advance the science of tsunami sediment transport modeling. Uncertainty may be decreased with additional laboratory studies that increase our understanding of the semi-empirical parameters and physics of tsunami sediment transport, standardized benchmark tests to assess model performance, and development of hybrid modeling approaches to exploit the strengths of forward and inverse models.

  14. What is the fault that has generated the earthquake on 8 September 1905 in Calabria, Italy? Source models compared by tsunami data

    NASA Astrophysics Data System (ADS)

    Pagnoni, Gianluca; Armigliato, Alberto; Tinti, Stefano; Loreto, Maria Filomena; Facchin, Lorenzo

    2014-05-01

    The earthquake that the 8 September 1905 hit Calabria in southern Italy was the second Italian earthquake for magnitude in the last century. It destroyed many villages along the coast of the Gulf of Sant'Eufemia, caused more than 500 fatalities and has also generated a tsunami with non-destructive effects. The historical reports tell us that the tsunami caused major damage in the villages of Briatico, Bivona, Pizzo and Vibo Marina, located in the south part of the Sant'Eufemia gulf and minor damage to Tropea and to Scalea, this one being village located about 100 km far from the epicenter. Other reports include accounts of fishermen at sea during the tsunami. Further, the tsunami is visible on tide gauge records in Messina, Sicily, in Naples and in Civitavecchia, a harbour located to the north of Rome (Platania, 1907) In spite of the attention devoted by researchers to this case, until now, like for other tsunamigenic Italian earthquakes, the genetic structure of the earthquake is still not identified and debate is still open. In this context, tsunami simulations can provide contributions useful to find the source model more consistent with observational data. This approach was already followed by Piatanesi and Tinti (2002), who carried out numerical simulations of tsunamis from a number of local sources. In the last decade studies on this seismogenic area were int ensified resulting in new estimates for the 1905 earthquake magnitude (7.1 according to the CPTI11 catalogue) and in the suggestion of new source models. By using an improved tsunami simulation model, more accurate bathymetry data, this work tests the source models investigated by Piatanesi and Tinti (2002) and in addition the new fault models proposed by Cucci and Tertulliani (2010) and by Loreto et al. (2013). The simulations of the tsunami are calculated by means of the code, UBO-TSUFD, that solves the linear equations of Navier-Stokes in approximation of shallow water with the finite

  15. Tsunami-Generated Atmospheric Gravity Waves and Their Atmospheric and Ionospheric Effects: a Review and Some Recent Modeling Results

    NASA Astrophysics Data System (ADS)

    Hickey, M. P.

    2017-12-01

    Tsunamis propagate on the ocean surface at the shallow water phase speed which coincides with the phase speed of fast atmospheric gravity waves. The forcing frequency also corresponds with those of internal atmospheric gravity waves. Hence, the coupling and effective forcing of gravity waves due to tsunamis is particularly effective. The fast horizontal phase speeds of the resulting gravity waves allows them to propagate well into the thermosphere before viscous dissipation becomes strong, and the waves can achieve nonlinear amplitudes at these heights resulting in large amplitude traveling ionospheric disturbances (TIDs). Additionally, because the tsunami represents a moving source able to traverse large distances across the globe, the gravity waves and associated TIDs can be detected at large distances from the original tsunami (earthquake) source. Although it was during the mid 1970s when the tsunami source of gravity waves was first postulated, only relatively recently (over the last ten to fifteen years) has there has been a surge of interest in this research arena, driven largely by significant improvements in measurement technologies and computational capabilities. For example, the use of GPS measurements to derive total electron content has been a particularly powerful technique used to monitor the propagation and evolution of TIDs. Monitoring airglow variations driven by atmospheric gravity waves has also been a useful technique. The modeling of specific events and comparison with the observed gravity waves and/or TIDs has been quite revealing. In this talk I will review some of the most interesting aspects of this research and also discuss some interesting and outstanding issues that need to be addressed. New modeling results relevant to the Tohoku tsunami event will also be presented.

  16. Asteroid Generated Tsunami Workshop: Summary of NASA/NOAA Workshop

    NASA Technical Reports Server (NTRS)

    Morrison, David; Venkatapathy, Ethiraj

    2017-01-01

    A two-day workshop on tsunami generated by asteroid impacts in the ocean resulted in a broad consensus that the asteroid impact tsunami threat is not as great as previously thought, that airburst events in particular are unlikely to produce significant damage by tsunami, and that the tsunami contribution to the global ensemble impact hazard is substantially less than the contribution from land impacts. The workshop, led by Ethiraj Venkatapathy and David Morrison of NASA Ames, was organized into three sessions: 1) Near-field wave generation by the impact; 2) Long distance wave propagation; 3) Damage from coastal run-up and inundation, and associated hazard. Workshop approaches were to compare simulations to understand differences in the results and gain confidence in the modeling for both formation and propagation of tsunami from asteroid impacts, and to use this information for preliminary global risk assessment. The workshop focus was on smaller asteroids (diameter less than 250m), which represent the most frequent impacts.

  17. Near Source 2007 Peru Tsunami Runup Observations and Modeling

    NASA Astrophysics Data System (ADS)

    Borrero, J. C.; Fritz, H. M.; Kalligeris, N.; Broncano, P.; Ortega, E.

    2008-12-01

    On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a tsunami with locally focused runup heights of up to 10 m. A reconnaissance team was deployed two weeks after the event and investigated the tsunami effects at 51 sites. Three tsunami fatalities were reported south of the Paracas Peninsula in a sparsely populated desert area where the largest tsunami runup heights and massive inundation distances up to 2 km were measured. Numerical modeling of the earthquake source and tsunami suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the Paracas Peninsula, which blocked tsunami waves from propagating northward from the high slip region. As with all near field tsunamis, the waves struck within minutes of the massive ground shaking. Spontaneous evacuations coordinated by the Peruvian Coast Guard minimized the fatalities and illustrate the importance of community-based education and awareness programs. The residents of the fishing village Lagunilla were unaware of the tsunami hazard after an earthquake and did not evacuate, which resulted in 3 fatalities. Despite the relatively benign tsunami effects at Pisco from this event, the tsunami hazard for this city (and its liquefied natural gas terminal) cannot be underestimated. Between 1687 and 1868, the city of Pisco was destroyed 4 times by tsunami waves. Since then, two events (1974 and 2007) have resulted in partial inundation and moderate damage. The fact that potentially devastating tsunami runup heights were observed immediately south of the peninsula only serves to underscore this point.

  18. Tsunami Simulators in Physical Modelling - Concept to Practical Solutions

    NASA Astrophysics Data System (ADS)

    Chandler, Ian; Allsop, William; Robinson, David; Rossetto, Tiziana; McGovern, David; Todd, David

    2017-04-01

    Whilst many researchers have conducted simple 'tsunami impact' studies, few engineering tools are available to assess the onshore impacts of tsunami, with no agreed methods available to predict loadings on coastal defences, buildings or related infrastructure. Most previous impact studies have relied upon unrealistic waveforms (solitary or dam-break waves and bores) rather than full-duration tsunami waves, or have used simplified models of nearshore and over-land flows. Over the last 10+ years, pneumatic Tsunami Simulators for the hydraulic laboratory have been developed into an exciting and versatile technology, allowing the forces of real-world tsunami to be reproduced and measured in a laboratory environment for the first time. These devices have been used to model generic elevated and N-wave tsunamis up to and over simple shorelines, and at example coastal defences and infrastructure. They have also reproduced full-duration tsunamis including Mercator 2004 and Tohoku 2011, both at 1:50 scale. Engineering scale models of these tsunamis have measured wave run-up on simple slopes, forces on idealised sea defences, pressures / forces on buildings, and scour at idealised buildings. This presentation will describe how these Tsunami Simulators work, demonstrate how they have generated tsunami waves longer than the facilities within which they operate, and will present research results from three generations of Tsunami Simulators. Highlights of direct importance to natural hazard modellers and coastal engineers include measurements of wave run-up levels, forces on single and multiple buildings and comparison with previous theoretical predictions. Multiple buildings have two malign effects. The density of buildings to flow area (blockage ratio) increases water depths and flow velocities in the 'streets'. But the increased building densities themselves also increase the cost of flow per unit area (both personal and monetary). The most recent study with the Tsunami

  19. Hydrodynamic modeling of tsunamis from the Currituck landslide

    USGS Publications Warehouse

    Geist, E.L.; Lynett, P.J.; Chaytor, J.D.

    2009-01-01

    Tsunami generation from the Currituck landslide offshore North Carolina and propagation of waves toward the U.S. coastline are modeled based on recent geotechnical analysis of slide movement. A long and intermediate wave modeling package (COULWAVE) based on the non-linear Boussinesq equations are used to simulate the tsunami. This model includes procedures to incorporate bottom friction, wave breaking, and overland flow during runup. Potential tsunamis generated from the Currituck landslide are analyzed using four approaches: (1) tsunami wave history is calculated from several different scenarios indicated by geotechnical stability and mobility analyses; (2) a sensitivity analysis is conducted to determine the effects of both landslide failure duration during generation and bottom friction along the continental shelf during propagation; (3) wave history is calculated over a regional area to determine the propagation of energy oblique to the slide axis; and (4) a high-resolution 1D model is developed to accurately model wave breaking and the combined influence of nonlinearity and dispersion during nearshore propagation and runup. The primary source parameter that affects tsunami severity for this case study is landslide volume, with failure duration having a secondary influence. Bottom friction during propagation across the continental shelf has a strong influence on the attenuation of the tsunami during propagation. The high-resolution 1D model also indicates that the tsunami undergoes nonlinear fission prior to wave breaking, generating independent, short-period waves. Wave breaking occurs approximately 40-50??km offshore where a tsunami bore is formed that persists during runup. These analyses illustrate the complex nature of landslide tsunamis, necessitating the use of detailed landslide stability/mobility models and higher-order hydrodynamic models to determine their hazard.

  20. Theoretical analysis of tsunami generation by pyroclastic flows

    USGS Publications Warehouse

    Watts, P.; Waythomas, C.F.

    2003-01-01

    Pyroclastic flows are a common product of explosive volcanism and have the potential to initiate tsunamis whenever thick, dense flows encounter bodies of water. We evaluate the process of tsunami generation by pyroclastic flow by decomposing the pyroclastic flow into two components, the dense underflow portion, which we term the pyroclastic debris flow, and the plume, which includes the surge and coignimbrite ash cloud parts of the flow. We consider five possible wave generation mechanisms. These mechanisms consist of steam explosion, pyroclastic debris flow, plume pressure, plume shear, and pressure impulse wave generation. Our theoretical analysis of tsunami generation by these mechanisms provides an estimate of tsunami features such as a characteristic wave amplitude and wavelength. We find that in most situations, tsunami generation is dominated by the pyroclastic debris flow component of a pyroclastic flow. This work presents information sufficient to construct tsunami sources for an arbitrary pyroclastic flow interacting with most bodies of water. Copyright 2003 by the American Geophysical Union.

  1. Earthquake mechanism and seafloor deformation for tsunami generation

    USGS Publications Warehouse

    Geist, Eric L.; Oglesby, David D.; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan

    2014-01-01

    Tsunamis are generated in the ocean by rapidly displacing the entire water column over a significant area. The potential energy resulting from this disturbance is balanced with the kinetic energy of the waves during propagation. Only a handful of submarine geologic phenomena can generate tsunamis: large-magnitude earthquakes, large landslides, and volcanic processes. Asteroid and subaerial landslide impacts can generate tsunami waves from above the water. Earthquakes are by far the most common generator of tsunamis. Generally, earthquakes greater than magnitude (M) 6.5–7 can generate tsunamis if they occur beneath an ocean and if they result in predominantly vertical displacement. One of the greatest uncertainties in both deterministic and probabilistic hazard assessments of tsunamis is computing seafloor deformation for earthquakes of a given magnitude.

  2. Tsunami Hazard Assessment: Source regions of concern to U.S. interests derived from NOAA Tsunami Forecast Model Development

    NASA Astrophysics Data System (ADS)

    Eble, M. C.; uslu, B. U.; Wright, L.

    2013-12-01

    Synthetic tsunamis generated from source regions around the Pacific Basin are analyzed in terms of their relative impact on United States coastal locations.. The region of tsunami origin is as important as the expected magnitude and the predicted inundation for understanding tsunami hazard. The NOAA Center for Tsunami Research has developed high-resolution tsunami models capable of predicting tsunami arrival time and amplitude of waves at each location. These models have been used to conduct tsunami hazard assessments to assess maximum impact and tsunami inundation for use by local communities in education and evacuation map development. Hazard assessment studies conducted for Los Angeles, San Francisco, Crescent City, Hilo, and Apra Harbor are combined with results of tsunami forecast model development at each of seventy-five locations. Complete hazard assessment, identifies every possible tsunami variation from a pre-computed propagation database. Study results indicate that the Eastern Aleutian Islands and Alaska are the most likely regions to produce the largest impact on the West Coast of the United States, while the East Philippines and Mariana trench regions impact Apra Harbor, Guam. Hawaii appears to be impacted equally from South America, Alaska and the Kuril Islands.

  3. Preliminary investigation of the hazard faced by Western Australia from tsunami generated along the Sunda Arc

    NASA Astrophysics Data System (ADS)

    Burbidge, D.; Cummins, P. R.

    2005-12-01

    Since the Boxing Day tsunami various countries surrounding the Indian Ocean have been investigating the potential hazard from trans-Indian Ocean tsunami generated along the Sunda Arc, south of Indonesia. This study presents some preliminary estimates of the tsunami hazard faced by Western Australia from tsunami generated along the Arc. To estimate the hazard, a suite of tsunami spaced evenly along the subduction zone to the south of Indonesia were numerically modelled. Offshore wave heights from tsunami generated in this region are significantly higher along northwestern part of the Western Australian coast from Exmouth to the Kimberly than they are along the rest of the coast south of Exmouth. Due to the offshore bathymetry, the area around Onslow in particular may face a higher tsunami than other areas the West Australian coast. Earthquakes between Java and Timor are likely to produce the greatest hazard to northwest WA. Earthquakes off Sumatra are likely the main source of tsunami hazard to locations south of Exmouth, however the hazard here is likely to be lower than that along the north western part of the West Australian coast. Tsunami generated by other sources (eg large intra-plate events, volcanoes, landslides and asteroids) could threaten other parts of the coast.

  4. Tsunami-HySEA model validation for tsunami current predictions

    NASA Astrophysics Data System (ADS)

    Macías, Jorge; Castro, Manuel J.; González-Vida, José Manuel; Ortega, Sergio

    2016-04-01

    Model ability to compute and predict tsunami flow velocities is of importance in risk assessment and hazard mitigation. Substantial damage can be produced by high velocity flows, particularly in harbors and bays, even when the wave height is small. Besides, an accurate simulation of tsunami flow velocities and accelerations is fundamental for advancing in the study of tsunami sediment transport. These considerations made the National Tsunami Hazard Mitigation Program (NTHMP) proposing a benchmark exercise focussed on modeling and simulating tsunami currents. Until recently, few direct measurements of tsunami velocities were available to compare and to validate model results. After Tohoku 2011 many current meters measurement were made, mainly in harbors and channels. In this work we present a part of the contribution made by the EDANYA group from the University of Malaga to the NTHMP workshop organized at Portland (USA), 9-10 of February 2015. We have selected three out of the five proposed benchmark problems. Two of them consist in real observed data from the Tohoku 2011 event, one at Hilo Habour (Hawaii) and the other at Tauranga Bay (New Zealand). The third one consists in laboratory experimental data for the inundation of Seaside City in Oregon. Acknowledgements: This research has been partially supported by the Junta de Andalucía research project TESELA (P11-RNM7069) and the Spanish Government Research project DAIFLUID (MTM2012-38383-C02-01) and Universidad de Málaga, Campus de Excelencia Andalucía TECH. The GPU and multi-GPU computations were performed at the Unit of Numerical Methods (UNM) of the Research Support Central Services (SCAI) of the University of Malaga.

  5. A review of mechanisms and modelling procedures for landslide tsunamis

    NASA Astrophysics Data System (ADS)

    Løvholt, Finn; Harbitz, Carl B.; Glimsdal, Sylfest

    2017-04-01

    Landslides, including volcano flank collapses or volcanically induced flows, constitute the second-most important cause of tsunamis after earthquakes. Compared to earthquakes, landslides are more diverse with respect to how they generation tsunamis. Here, we give an overview over the main tsunami generation mechanisms for landslide tsunamis. In the presentation, a mix of results using analytical models, numerical models, laboratory experiments, and case studies are used to illustrate the diversity, but also to point out some common characteristics. Different numerical modelling techniques for the landslide evolution, and the tsunami generation and propagation, as well as the effect of frequency dispersion, are also briefly discussed. Basic tsunami generation mechanisms for different types of landslides, including large submarine translational landslide, to impulsive submarine slumps, and violent subaerial landslides and volcano flank collapses, are reviewed. The importance of the landslide kinematics is given attention, including the interplay between landslide acceleration, landslide velocity to depth ratio (Froude number) and dimensions. Using numerical simulations, we demonstrate how landslide deformation and retrogressive failure development influence tsunamigenesis. Generation mechanisms for subaerial landslides, are reviewed by means of scaling relations from laboratory experiments and numerical modelling. Finally, it is demonstrated how the different degree of complexity in the landslide tsunamigenesis needs to be reflected by increased sophistication in numerical models.

  6. Tsunami Propagation Models Based on First Principles

    DTIC Science & Technology

    2012-11-21

    geodesic lines from the epicenter shown in the figure are great circles with a longitudinal separation of 90o, which define a ‘ lune ’ that covers one...past which the waves begin to converge according to Model C. A tsunami propagating in this lune does not encounter any continental landmass until...2011 Japan tsunami in a lune of angle 90o with wavefronts at intervals of 5,000 km The 2011 Japan tsunami was felt throughout the Pacific Ocean

  7. Development, testing, and applications of site-specific tsunami inundation models for real-time forecasting

    NASA Astrophysics Data System (ADS)

    Tang, L.; Titov, V. V.; Chamberlin, C. D.

    2009-12-01

    The study describes the development, testing and applications of site-specific tsunami inundation models (forecast models) for use in NOAA's tsunami forecast and warning system. The model development process includes sensitivity studies of tsunami wave characteristics in the nearshore and inundation, for a range of model grid setups, resolutions and parameters. To demonstrate the process, four forecast models in Hawaii, at Hilo, Kahului, Honolulu, and Nawiliwili are described. The models were validated with fourteen historical tsunamis and compared with numerical results from reference inundation models of higher resolution. The accuracy of the modeled maximum wave height is greater than 80% when the observation is greater than 0.5 m; when the observation is below 0.5 m the error is less than 0.3 m. The error of the modeled arrival time of the first peak is within 3% of the travel time. The developed forecast models were further applied to hazard assessment from simulated magnitude 7.5, 8.2, 8.7 and 9.3 tsunamis based on subduction zone earthquakes in the Pacific. The tsunami hazard assessment study indicates that use of a seismic magnitude alone for a tsunami source assessment is inadequate to achieve such accuracy for tsunami amplitude forecasts. The forecast models apply local bathymetric and topographic information, and utilize dynamic boundary conditions from the tsunami source function database, to provide site- and event-specific coastal predictions. Only by combining a Deep-ocean Assessment and Reporting of Tsunami-constrained tsunami magnitude with site-specific high-resolution models can the forecasts completely cover the evolution of earthquake-generated tsunami waves: generation, deep ocean propagation, and coastal inundation. Wavelet analysis of the tsunami waves suggests the coastal tsunami frequency responses at different sites are dominated by the local bathymetry, yet they can be partially related to the locations of the tsunami sources. The study

  8. Quantifying Coastal Hazard of Airburst-Generated Tsunamis

    NASA Astrophysics Data System (ADS)

    Titov, V. V.; Boslough, M.

    2017-12-01

    The effort to prevent or mitigate the effects of an impact on Earth is known as planetary defense. A significant component of planetary defense research involves risk assessment. Much of our understanding of the risk from near-Earth objects comes from the geologic record in the form of impact craters, but not all asteroid impacts are crater-forming events. Small asteroids explode before reaching the surface, generating an airburst, and most impacts into the ocean do not penetrate the water to form a crater in the sea floor. The risk from these non-crater-forming ocean impacts and airbursts is difficult to quantify and represents a significant uncertainty in our assessment of the overall threat. One of the suggested mechanisms for the production of asteroid-generated tsunami is by direct coupling of the pressure wave to the water, analogous to the means by which a moving weather front can generate a meteotsunami. To test this hypothesis, we have run a series of airburst simulations and provided time-resolved pressure and wind profiles for tsunami modelers to use as source functions. We used hydrocodes to model airburst scenarios and provide time dependent boundary conditions as input to shallow-water wave propagation codes. The strongest and most destructive meteotsunami are generated by atmospheric pressure oscillations with amplitudes of only a few hPa, corresponding to changes in sea level of a few cm. The resulting wave is strongest when there is a resonance between the ocean and the atmospheric forcing. The blast wave from an airburst propagates at a speed close to a tsunami speed only in the deepest part of the ocean, and a Proudman resonance cannot be usually achieved even though the overpressures are orders of magnitude greater. However, blast wave profiles are N-waves in which a sharp shock wave leading to overpressure is followed by a more gradual rarefaction to a much longer-duration underpressure phase. Even though the blast outruns the water wave it is

  9. Source parameters controlling the generation and propagation of potential local tsunamis along the cascadia margin

    USGS Publications Warehouse

    Geist, E.; Yoshioka, S.

    1996-01-01

    The largest uncertainty in assessing hazards from local tsunamis along the Cascadia margin is estimating the possible earthquake source parameters. We investigate which source parameters exert the largest influence on tsunami generation and determine how each parameter affects the amplitude of the local tsunami. The following source parameters were analyzed: (1) type of faulting characteristic of the Cascadia subduction zone, (2) amount of slip during rupture, (3) slip orientation, (4) duration of rupture, (5) physical properties of the accretionary wedge, and (6) influence of secondary faulting. The effect of each of these source parameters on the quasi-static displacement of the ocean floor is determined by using elastic three-dimensional, finite-element models. The propagation of the resulting tsunami is modeled both near the coastline using the two-dimensional (x-t) Peregrine equations that includes the effects of dispersion and near the source using the three-dimensional (x-y-t) linear long-wave equations. The source parameters that have the largest influence on local tsunami excitation are the shallowness of rupture and the amount of slip. In addition, the orientation of slip has a large effect on the directivity of the tsunami, especially for shallow dipping faults, which consequently has a direct influence on the length of coastline inundated by the tsunami. Duration of rupture, physical properties of the accretionary wedge, and secondary faulting all affect the excitation of tsunamis but to a lesser extent than the shallowness of rupture and the amount and orientation of slip. Assessment of the severity of the local tsunami hazard should take into account that relatively large tsunamis can be generated from anomalous 'tsunami earthquakes' that rupture within the accretionary wedge in comparison to interplate thrust earthquakes of similar magnitude. ?? 1996 Kluwer Academic Publishers.

  10. Tsunami Risk Assessment Modelling in Chabahar Port, Iran

    NASA Astrophysics Data System (ADS)

    Delavar, M. R.; Mohammadi, H.; Sharifi, M. A.; Pirooz, M. D.

    2017-09-01

    The well-known historical tsunami in the Makran Subduction Zone (MSZ) region was generated by the earthquake of November 28, 1945 in Makran Coast in the North of Oman Sea. This destructive tsunami killed over 4,000 people in Southern Pakistan and India, caused great loss of life and devastation along the coasts of Western India, Iran and Oman. According to the report of "Remembering the 1945 Makran Tsunami", compiled by the Intergovernmental Oceanographic Commission (UNESCO/IOC), the maximum inundation of Chabahar port was 367 m toward the dry land, which had a height of 3.6 meters from the sea level. In addition, the maximum amount of inundation at Pasni (Pakistan) reached to 3 km from the coastline. For the two beaches of Gujarat (India) and Oman the maximum run-up height was 3 m from the sea level. In this paper, we first use Makran 1945 seismic parameters to simulate the tsunami in generation, propagation and inundation phases. The effect of tsunami on Chabahar port is simulated using the ComMIT model which is based on the Method of Splitting Tsunami (MOST). In this process the results are compared with the documented eyewitnesses and some reports from researchers for calibration and validation of the result. Next we have used the model to perform risk assessment for Chabahar port in the south of Iran with the worst case scenario of the tsunami. The simulated results showed that the tsunami waves will reach Chabahar coastline 11 minutes after generation and 9 minutes later, over 9.4 Km2 of the dry land will be flooded with maximum wave amplitude reaching up to 30 meters.

  11. Observations and Modeling of the August 27, 2012 Earthquake and Tsunami affecting El Salvador and Nicaragua

    NASA Astrophysics Data System (ADS)

    Borrero, Jose C.; Kalligeris, Nikos; Lynett, Patrick J.; Fritz, Hermann M.; Newman, Andrew V.; Convers, Jaime A.

    2014-12-01

    On 27 August 2012 (04:37 UTC, 26 August 10:37 p.m. local time) a magnitude M w = 7.3 earthquake occurred off the coast of El Salvador and generated surprisingly large local tsunami. Following the event, local and international tsunami teams surveyed the tsunami effects in El Salvador and northern Nicaragua. The tsunami reached a maximum height of ~6 m with inundation of up to 340 m inland along a 25 km section of coastline in eastern El Salvador. Less severe inundation was reported in northern Nicaragua. In the far-field, the tsunami was recorded by a DART buoy and tide gauges in several locations of the eastern Pacific Ocean but did not cause any damage. The field measurements and recordings are compared to numerical modeling results using initial conditions of tsunami generation based on finite-fault earthquake and tsunami inversions and a uniform slip model.

  12. The TRIDEC Virtual Tsunami Atlas - customized value-added simulation data products for Tsunami Early Warning generated on compute clusters

    NASA Astrophysics Data System (ADS)

    Löwe, P.; Hammitzsch, M.; Babeyko, A.; Wächter, J.

    2012-04-01

    The development of new Tsunami Early Warning Systems (TEWS) requires the modelling of spatio-temporal spreading of tsunami waves both recorded from past events and hypothetical future cases. The model results are maintained in digital repositories for use in TEWS command and control units for situation assessment once a real tsunami occurs. Thus the simulation results must be absolutely trustworthy, in a sense that the quality of these datasets is assured. This is a prerequisite as solid decision making during a crisis event and the dissemination of dependable warning messages to communities under risk will be based on them. This requires data format validity, but even more the integrity and information value of the content, being a derived value-added product derived from raw tsunami model output. Quality checking of simulation result products can be done in multiple ways, yet the visual verification of both temporal and spatial spreading characteristics for each simulation remains important. The eye of the human observer still remains an unmatched tool for the detection of irregularities. This requires the availability of convenient, human-accessible mappings of each simulation. The improvement of tsunami models necessitates the changes in many variables, including simulation end-parameters. Whenever new improved iterations of the general models or underlying spatial data are evaluated, hundreds to thousands of tsunami model results must be generated for each model iteration, each one having distinct initial parameter settings. The use of a Compute Cluster Environment (CCE) of sufficient size allows the automated generation of all tsunami-results within model iterations in little time. This is a significant improvement to linear processing on dedicated desktop machines or servers. This allows for accelerated/improved visual quality checking iterations, which in turn can provide a positive feedback into the overall model improvement iteratively. An approach to set

  13. Mathematics of tsunami: modelling and identification

    NASA Astrophysics Data System (ADS)

    Krivorotko, Olga; Kabanikhin, Sergey

    2015-04-01

    Tsunami (long waves in the deep water) motion caused by underwater earthquakes is described by shallow water equations ( { ηtt = div (gH (x,y)-gradη), (x,y) ∈ Ω, t ∈ (0,T ); η|t=0 = q(x,y), ηt|t=0 = 0, (x,y) ∈ Ω. ( (1) Bottom relief H(x,y) characteristics and the initial perturbation data (a tsunami source q(x,y)) are required for the direct simulation of tsunamis. The main difficulty problem of tsunami modelling is a very big size of the computational domain (Ω = 500 × 1000 kilometres in space and about one hour computational time T for one meter of initial perturbation amplitude max|q|). The calculation of the function η(x,y,t) of three variables in Ω × (0,T) requires large computing resources. We construct a new algorithm to solve numerically the problem of determining the moving tsunami wave height S(x,y) which is based on kinematic-type approach and analytical representation of fundamental solution. Proposed algorithm of determining the function of two variables S(x,y) reduces the number of operations in 1.5 times than solving problem (1). If all functions does not depend on the variable y (one dimensional case), then the moving tsunami wave height satisfies of the well-known Airy-Green formula: S(x) = S(0)° --- 4H (0)/H (x). The problem of identification parameters of a tsunami source using additional measurements of a passing wave is called inverse tsunami problem. We investigate two different inverse problems of determining a tsunami source q(x,y) using two different additional data: Deep-ocean Assessment and Reporting of Tsunamis (DART) measurements and satellite altimeters wave-form images. These problems are severely ill-posed. The main idea consists of combination of two measured data to reconstruct the source parameters. We apply regularization techniques to control the degree of ill-posedness such as Fourier expansion, truncated singular value decomposition, numerical regularization. The algorithm of selecting the truncated number of

  14. Modeling Extra-Long Tsunami Propagation: Assessing Data, Model Accuracy and Forecast Implications

    NASA Astrophysics Data System (ADS)

    Titov, V. V.; Moore, C. W.; Rabinovich, A.

    2017-12-01

    Detecting and modeling tsunamis propagating tens of thousands of kilometers from the source is a formidable scientific challenge and seemingly satisfies only scientific curiosity. However, results of such analyses produce a valuable insight into the tsunami propagation dynamics, model accuracy and would provide important implications for tsunami forecast. The Mw = 9.3 megathrust earthquake of December 26, 2004 off the coast of Sumatra generated a tsunami that devastated Indian Ocean coastlines and spread into the Pacific and Atlantic oceans. The tsunami was recorded by a great number of coastal tide gauges, including those located in 15-25 thousand kilometers from the source area. To date, it is still the farthest instrumentally detected tsunami. The data from these instruments throughout the world oceans enabled to estimate various statistical parameters and energy decay of this event. High-resolution records of this tsunami from DARTs 32401 (offshore of northern Chile), 46405 and NeMO (both offshore of the US West Coast), combined with the mainland tide gauge measurements enabled us to examine far-field characteristics of the 2004 in the Pacific Ocean and to compare the results of global numerical simulations with the observations. Despite their small heights (less than 2 cm at deep-ocean locations), the records demonstrated consistent spatial and temporal structure. The numerical model described well the frequency content, amplitudes and general structure of the observed waves at deep-ocean and coastal gages. We present analysis of the measurements and comparison with model data to discuss implication for tsunami forecast accuracy. Model study for such extreme distances from the tsunami source and at extra-long times after the event is an attempt to find accuracy bounds for tsunami models and accuracy limitations of model use for forecast. We discuss results in application to tsunami model forecast and tsunami modeling in general.

  15. Volcanic Tsunami Generation in the Aleutian Arc of Alaska

    NASA Astrophysics Data System (ADS)

    Waythomas, C. F.; Watts, P.

    2003-12-01

    Many of the worlds active volcanoes are situated on or near coastlines, and during eruptions the transfer of mass from volcano to sea is a potential source mechanism for tsunamis. Flows of granular material off of volcanoes, such as pyroclastic flow, debris avalanche, and lahar, often deliver large volumes of unconsolidated debris to the ocean that have a large potential tsunami hazard. The deposits of both hot and cold volcanic grain flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and Cook Inlet indicating that the flows entered the sea and in some cases may have initiated tsunamis. We evaluate the process of tsunami generation by granular subaerial volcanic flows using examples from Aniakchak volcano in southwestern Alaska, and Augustine volcano in southern Cook Inlet. Evidence for far-field tsunami inundation coincident with a major caldera-forming eruption of Aniakchak volcano ca. 3.5 ka has been described and is the basis for one of our case studies. We perform a numerical simulation of the tsunami using a large volume pyroclastic flow as the source mechanism and compare our results to field measurements of tsunami deposits preserved along the north shore of Bristol Bay. Several attributes of the tsunami simulation, such as water flux and wave amplitude, are reasonable predictors of tsunami deposit thickness and generally agree with the field evidence for tsunami inundation. At Augustine volcano, geological investigations suggest that as many as 14 large volcanic-rock avalanches have reached the sea in the last 2000 years, and a debris avalanche emplaced during the 1883 eruption may have initiated a tsunami observed about 80 km east of the volcano at the village of English Bay (Nanwalek) on the coast of the southern Kenai Peninsula. By analogy with the 1883 event, previous studies concluded that tsunamis could have been generated many times in the past. If so

  16. Solomon Islands 2007 Tsunami Near-Field Modeling and Source Earthquake Deformation

    NASA Astrophysics Data System (ADS)

    Uslu, B.; Wei, Y.; Fritz, H.; Titov, V.; Chamberlin, C.

    2008-12-01

    The earthquake of 1 April 2007 left behind momentous footages of crust rupture and tsunami impact along the coastline of Solomon Islands (Fritz and Kalligeris, 2008; Taylor et al., 2008; McAdoo et al., 2008; PARI, 2008), while the undisturbed tsunami signals were also recorded at nearby deep-ocean tsunameters and coastal tide stations. These multi-dimensional measurements provide valuable datasets to tackle the challenging aspects at the tsunami source directly by inversion from tsunameter records in real time (available in a time frame of minutes), and its relationship with the seismic source derived either from the seismometer records (available in a time frame of hours or days) or from the crust rupture measurements (available in a time frame of months or years). The tsunami measurements in the near field, including the complex vertical crust motion and tsunami runup, are particularly critical to help interpreting the tsunami source. This study develops high-resolution inundation models for the Solomon Islands to compute the near-field tsunami impact. Using these models, this research compares the tsunameter-derived tsunami source with the seismic-derived earthquake sources from comprehensive perceptions, including vertical uplift and subsidence, tsunami runup heights and their distributional pattern among the islands, deep-ocean tsunameter measurements, and near- and far-field tide gauge records. The present study stresses the significance of the tsunami magnitude, source location, bathymetry and topography in accurately modeling the generation, propagation and inundation of the tsunami waves. This study highlights the accuracy and efficiency of the tsunameter-derived tsunami source in modeling the near-field tsunami impact. As the high- resolution models developed in this study will become part of NOAA's tsunami forecast system, these results also suggest expanding the system for potential applications in tsunami hazard assessment, search and rescue operations

  17. Tsunamis generated by subaerial mass flows

    USGS Publications Warehouse

    Walder, S.J.; Watts, P.; Sorensen, O.E.; Janssen, K.

    2003-01-01

    Tsunamis generated in lakes and reservoirs by subaerial mass flows pose distinctive problems for hazards assessment because the domain of interest is commonly the "near field," beyond the zone of complex splashing but close enough to the source that wave propagation effects are not predominant. Scaling analysis of the equations governing water wave propagation shows that near-field wave amplitude and wavelength should depend on certain measures of mass flow dynamics and volume. The scaling analysis motivates a successful collapse (in dimensionless space) of data from two distinct sets of experiments with solid block "wave makers." To first order, wave amplitude/water depth is a simple function of the ratio of dimensionless wave maker travel time to dimensionless wave maker volume per unit width. Wave amplitude data from previous laboratory investigations with both rigid and deformable wave makers follow the same trend in dimensionless parameter space as our own data. The characteristic wavelength/water depth for all our experiments is simply proportional to dimensionless wave maker travel time, which is itself given approximately by a simple function of wave maker length/water depth. Wave maker shape and rigidity do not otherwise influence wave features. Application of the amplitude scaling relation to several historical events yields "predicted" near-field wave amplitudes in reasonable agreement with measurements and observations. Together, the scaling relations for near-field amplitude, wavelength, and submerged travel time provide key inputs necessary for computational wave propagation and hazards assessment.

  18. Method to Determine Appropriate Source Models of Large Earthquakes Including Tsunami Earthquakes for Tsunami Early Warning in Central America

    NASA Astrophysics Data System (ADS)

    Tanioka, Yuichiro; Miranda, Greyving Jose Arguello; Gusman, Aditya Riadi; Fujii, Yushiro

    2017-08-01

    Large earthquakes, such as the Mw 7.7 1992 Nicaragua earthquake, have occurred off the Pacific coasts of El Salvador and Nicaragua in Central America and have generated distractive tsunamis along these coasts. It is necessary to determine appropriate fault models before large tsunamis hit the coast. In this study, first, fault parameters were estimated from the W-phase inversion, and then an appropriate fault model was determined from the fault parameters and scaling relationships with a depth dependent rigidity. The method was tested for four large earthquakes, the 1992 Nicaragua tsunami earthquake (Mw7.7), the 2001 El Salvador earthquake (Mw7.7), the 2004 El Astillero earthquake (Mw7.0), and the 2012 El Salvador-Nicaragua earthquake (Mw7.3), which occurred off El Salvador and Nicaragua in Central America. The tsunami numerical simulations were carried out from the determined fault models. We found that the observed tsunami heights, run-up heights, and inundation areas were reasonably well explained by the computed ones. Therefore, our method for tsunami early warning purpose should work to estimate a fault model which reproduces tsunami heights near the coast of El Salvador and Nicaragua due to large earthquakes in the subduction zone.

  19. Unique and remarkable dilatometer measurements of pyroclastic flow generated tsunamis

    NASA Astrophysics Data System (ADS)

    Mattioli, G. S.; Voight, B.; Linde, A. T.; Sacks, I. S.; Watts, P.; Widiwijayanti, C.; Young, S. R.; Hidayat, D.; Elsworth, D.; Malin, P. E.; Shalev, E.; van Boskirk, E.; Johnston, W.; Sparks, R. S. J.; Neuberg, J.; Bass, V.; Dunkley, P.; Herd, R.; Syers, T.; Williams, P.; Williams, D.

    2007-01-01

    Pyroclastic flows entering the sea may cause tsunamis at coastal volcanoes worldwide, but geophysically monitored field occurrences are rare. We document the process of tsunami generation during a prolonged gigantic collapse of the Soufrière Hills volcano lava dome on Montserrat on 12 13 July 2003. Tsunamis were initiated by large-volume pyroclastic flows entering the ocean. We reconstruct the collapse from seismic records and report unique and remarkable borehole dilatometer observations, which recorded clearly the passage of wave packets at periods of 250 500 s over several hours. Strain signals are consistent in period and amplitude with water loading from passing tsunamis; each wave packet can be correlated with individual pyroclastic flow packages recorded by seismic data, proving that multiple tsunamis were initiated by pyroclastic flows. Any volcano within a few kilometers of water and capable of generating hot pyroclastic flows or cold debris flows with volumes greater than 5 × 106 m3 may generate significant and possibly damaging tsunamis during future eruptions.

  20. Tsunami Source Modeling of the 2015 Volcanic Tsunami Earthquake near Torishima, South of Japan

    NASA Astrophysics Data System (ADS)

    Sandanbata, O.; Watada, S.; Satake, K.; Fukao, Y.; Sugioka, H.; Ito, A.; Shiobara, H.

    2017-12-01

    An abnormal earthquake occurred at a submarine volcano named Smith Caldera, near Torishima Island on the Izu-Bonin arc, on May 2, 2015. The earthquake, which hereafter we call "the 2015 Torishima earthquake," has a CLVD-type focal mechanism with a moderate seismic magnitude (M5.7) but generated larger tsunami waves with an observed maximum height of 50 cm at Hachijo Island [JMA, 2015], so that the earthquake can be regarded as a "tsunami earthquake." In the region, similar tsunami earthquakes were observed in 1984, 1996 and 2006, but their physical mechanisms are still not well understood. Tsunami waves generated by the 2015 earthquake were recorded by an array of ocean bottom pressure (OBP) gauges, 100 km northeastern away from the epicenter. The waves initiated with a small downward signal of 0.1 cm and reached peak amplitude (1.5-2.0 cm) of leading upward signals followed by continuous oscillations [Fukao et al., 2016]. For modeling its tsunami source, or sea-surface displacement, we perform tsunami waveform simulations, and compare synthetic and observed waveforms at the OBP gauges. The linear Boussinesq equations are adapted with the tsunami simulation code, JAGURS [Baba et al., 2015]. We first assume a Gaussian-shaped sea-surface uplift of 1.0 m with a source size comparable to Smith Caldera, 6-7 km in diameter. By shifting source location around the caldera, we found the uplift is probably located within the caldera rim, as suggested by Sandanbata et al. [2016]. However, synthetic waves show no initial downward signal that was observed at the OBP gauges. Hence, we add a ring of subsidence surrounding the main uplift, and examine sizes and amplitudes of the main uplift and the subsidence ring. As a result, the model of a main uplift of around 1.0 m with a radius of 4 km surrounded by a ring of small subsidence shows good agreement of synthetic and observed waveforms. The results yield two implications for the deformation process that help us to understanding

  1. 3D Numerical Simulation on the Rockslide Generated Tsunamis

    NASA Astrophysics Data System (ADS)

    Chuang, M.; Wu, T.; Wang, C.; Chu, C.

    2013-12-01

    The rockslide generated tsunami is one of the most devastating nature hazards. However, the involvement of the moving obstacle and dynamic free-surface movement makes the numerical simulation a difficult task. To describe both the fluid motion and solid movement at the same time, we newly developed a two-way fully-coupled moving solid algorithm with 3D LES turbulent model. The free-surface movement is tracked by volume of fluid (VOF) method. The two-step projection method is adopted to solve the Navier-Stokes type government equations. In the new moving solid algorithm, a fictitious body force is implicitly prescribed in MAC correction step to make the cell-center velocity satisfied with the obstacle velocity. We called this method the implicit velocity method (IVM). Because no extra terms are added to the pressure Poission correction, the pressure field of the fluid part is stable, which is the key of the two-way fluid-solid coupling. Because no real solid material is presented in the IVM, the time marching step is not restricted to the smallest effective grid size. Also, because the fictitious force is implicitly added to the correction step, the resulting velocity is accurate and fully coupled with the resulting pressure field. We validated the IVM by simulating a floating box moving up and down on the free-surface. We presented the time-history obstacle trajectory and compared it with the experimental data. Very accurate result can be seen in terms of the oscillating amplitude and the period (Fig. 1). We also presented the free-surface comparison with the high-speed snapshots. At the end, the IVM was used to study the rock-slide generated tsunamis (Liu et al., 2005). Good validations on the slide trajectory and the free-surface movement will be presented in the full paper. From the simulation results (Fig. 2), we observed that the rockslide generated waves are manly caused by the rebounding waves from two sides of the sliding rock after the water is dragging

  2. A simple model for calculating tsunami flow speed from tsunami deposits

    USGS Publications Warehouse

    Jaffe, B.E.; Gelfenbuam, G.

    2007-01-01

    This paper presents a simple model for tsunami sedimentation that can be applied to calculate tsunami flow speed from the thickness and grain size of a tsunami deposit (the inverse problem). For sandy tsunami deposits where grain size and thickness vary gradually in the direction of transport, tsunami sediment transport is modeled as a steady, spatially uniform process. The amount of sediment in suspension is assumed to be in equilibrium with the steady portion of the long period, slowing varying uprush portion of the tsunami. Spatial flow deceleration is assumed to be small and not to contribute significantly to the tsunami deposit. Tsunami deposits are formed from sediment settling from the water column when flow speeds on land go to zero everywhere at the time of maximum tsunami inundation. There is little erosion of the deposit by return flow because it is a slow flow and is concentrated in topographic lows. Variations in grain size of the deposit are found to have more effect on calculated tsunami flow speed than deposit thickness. The model is tested using field data collected at Arop, Papua New Guinea soon after the 1998 tsunami. Speed estimates of 14??m/s at 200??m inland from the shoreline compare favorably with those from a 1-D inundation model and from application of Bernoulli's principle to water levels on buildings left standing after the tsunami. As evidence that the model is applicable to some sandy tsunami deposits, the model reproduces the observed normal grading and vertical variation in sorting and skewness of a deposit formed by the 1998 tsunami.

  3. Explanation of temporal clustering of tsunami sources using the epidemic-type aftershock sequence model

    USGS Publications Warehouse

    Geist, Eric L.

    2014-01-01

    Temporal clustering of tsunami sources is examined in terms of a branching process model. It previously was observed that there are more short interevent times between consecutive tsunami sources than expected from a stationary Poisson process. The epidemic‐type aftershock sequence (ETAS) branching process model is fitted to tsunami catalog events, using the earthquake magnitude of the causative event from the Centennial and Global Centroid Moment Tensor (CMT) catalogs and tsunami sizes above a completeness level as a mark to indicate that a tsunami was generated. The ETAS parameters are estimated using the maximum‐likelihood method. The interevent distribution associated with the ETAS model provides a better fit to the data than the Poisson model or other temporal clustering models. When tsunamigenic conditions (magnitude threshold, submarine location, dip‐slip mechanism) are applied to the Global CMT catalog, ETAS parameters are obtained that are consistent with those estimated from the tsunami catalog. In particular, the dip‐slip condition appears to result in a near zero magnitude effect for triggered tsunami sources. The overall consistency between results from the tsunami catalog and that from the earthquake catalog under tsunamigenic conditions indicates that ETAS models based on seismicity can provide the structure for understanding patterns of tsunami source occurrence. The fractional rate of triggered tsunami sources on a global basis is approximately 14%.

  4. New Activities of the U.S. National Tsunami Hazard Mitigation Program, Mapping and Modeling Subcommittee

    NASA Astrophysics Data System (ADS)

    Wilson, R. I.; Eble, M. C.

    2013-12-01

    The U.S. National Tsunami Hazard Mitigation Program (NTHMP) is comprised of representatives from coastal states and federal agencies who, under the guidance of NOAA, work together to develop protocols and products to help communities prepare for and mitigate tsunami hazards. Within the NTHMP are several subcommittees responsible for complimentary aspects of tsunami assessment, mitigation, education, warning, and response. The Mapping and Modeling Subcommittee (MMS) is comprised of state and federal scientists who specialize in tsunami source characterization, numerical tsunami modeling, inundation map production, and warning forecasting. Until September 2012, much of the work of the MMS was authorized through the Tsunami Warning and Education Act, an Act that has since expired but the spirit of which is being adhered to in parallel with reauthorization efforts. Over the past several years, the MMS has developed guidance and best practices for states and territories to produce accurate and consistent tsunami inundation maps for community level evacuation planning, and has conducted benchmarking of numerical inundation models. Recent tsunami events have highlighted the need for other types of tsunami hazard analyses and products for improving evacuation planning, vertical evacuation, maritime planning, land-use planning, building construction, and warning forecasts. As the program responsible for producing accurate and consistent tsunami products nationally, the NTHMP-MMS is initiating a multi-year plan to accomplish the following: 1) Create and build on existing demonstration projects that explore new tsunami hazard analysis techniques and products, such as maps identifying areas of strong currents and potential damage within harbors as well as probabilistic tsunami hazard analysis for land-use planning. 2) Develop benchmarks for validating new numerical modeling techniques related to current velocities and landslide sources. 3) Generate guidance and protocols for

  5. Tsunamis

    MedlinePlus

    A tsunami is a series of huge ocean waves created by an underwater disturbance. Causes include earthquakes, landslides, volcanic ... space that strike the surface of Earth. A tsunami can move hundreds of miles per hour in ...

  6. Uncertainty in the Modeling of Tsunami Sediment Transport

    NASA Astrophysics Data System (ADS)

    Jaffe, B. E.; Sugawara, D.; Goto, K.; Gelfenbaum, G. R.; La Selle, S.

    2016-12-01

    Erosion and deposition from tsunamis record information about tsunami hydrodynamics and size that can be interpreted to improve tsunami hazard assessment. A recent study (Jaffe et al., 2016) explores sources and methods for quantifying uncertainty in tsunami sediment transport modeling. Uncertainty varies with tsunami properties, study site characteristics, available input data, sediment grain size, and the model used. Although uncertainty has the potential to be large, case studies for both forward and inverse models have shown that sediment transport modeling provides useful information on tsunami inundation and hydrodynamics that can be used to improve tsunami hazard assessment. New techniques for quantifying uncertainty, such as Ensemble Kalman Filtering inversion, and more rigorous reporting of uncertainties will advance the science of tsunami sediment transport modeling. Uncertainty may be decreased with additional laboratory studies that increase our understanding of the semi-empirical parameters and physics of tsunami sediment transport, standardized benchmark tests to assess model performance, and the development of hybrid modeling approaches to exploit the strengths of forward and inverse models. As uncertainty in tsunami sediment transport modeling is reduced, and with increased ability to quantify uncertainty, the geologic record of tsunamis will become more valuable in the assessment of tsunami hazard. Jaffe, B., Goto, K., Sugawara, D., Gelfenbaum, G., and La Selle, S., "Uncertainty in Tsunami Sediment Transport Modeling", Journal of Disaster Research Vol. 11 No. 4, pp. 647-661, 2016, doi: 10.20965/jdr.2016.p0647 https://www.fujipress.jp/jdr/dr/dsstr001100040647/

  7. A consistent model for tsunami actions on buildings

    NASA Astrophysics Data System (ADS)

    Foster, A.; Rossetto, T.; Eames, I.; Chandler, I.; Allsop, W.

    2016-12-01

    The Japan (2011) and Indian Ocean (2004) tsunami resulted in significant loss of life, buildings, and critical infrastructure. The tsunami forces imposed upon structures in coastal regions are initially due to wave slamming, after which the quasi-steady flow of the sea water around buildings becomes important. An essential requirement in both design and loss assessment is a consistent model that can accurately predict these forces. A model suitable for predicting forces in the in the quasi-steady range has been established as part of a systematic programme of research by the UCL EPICentre to understand the fundamental physical processes of tsunami actions on buildings, and more generally their social and economic consequences. Using the pioneering tsunami generator at HR Wallingford, this study considers the influence of unsteady flow conditions on the forces acting upon a rectangular building occupying 10-80% of a channel for 20-240 second wave periods. A mathematical model based upon basic open-channel flow principles is proposed, which provides empirical estimates for drag and hydrostatic coefficients. A simple force prediction equation, requiring only basic flow velocity and wave height inputs is then developed, providing good agreement with the experimental results. The results of this study demonstrate that the unsteady forces from the very long waves encountered during tsunami events can be predicted with a level of accuracy and simplicity suitable for design and risk assessment.

  8. Development of Parallel Code for the Alaska Tsunami Forecast Model

    NASA Astrophysics Data System (ADS)

    Bahng, B.; Knight, W. R.; Whitmore, P.

    2014-12-01

    The Alaska Tsunami Forecast Model (ATFM) is a numerical model used to forecast propagation and inundation of tsunamis generated by earthquakes and other means in both the Pacific and Atlantic Oceans. At the U.S. National Tsunami Warning Center (NTWC), the model is mainly used in a pre-computed fashion. That is, results for hundreds of hypothetical events are computed before alerts, and are accessed and calibrated with observations during tsunamis to immediately produce forecasts. ATFM uses the non-linear, depth-averaged, shallow-water equations of motion with multiply nested grids in two-way communications between domains of each parent-child pair as waves get closer to coastal waters. Even with the pre-computation the task becomes non-trivial as sub-grid resolution gets finer. Currently, the finest resolution Digital Elevation Models (DEM) used by ATFM are 1/3 arc-seconds. With a serial code, large or multiple areas of very high resolution can produce run-times that are unrealistic even in a pre-computed approach. One way to increase the model performance is code parallelization used in conjunction with a multi-processor computing environment. NTWC developers have undertaken an ATFM code-parallelization effort to streamline the creation of the pre-computed database of results with the long term aim of tsunami forecasts from source to high resolution shoreline grids in real time. Parallelization will also permit timely regeneration of the forecast model database with new DEMs; and, will make possible future inclusion of new physics such as the non-hydrostatic treatment of tsunami propagation. The purpose of our presentation is to elaborate on the parallelization approach and to show the compute speed increase on various multi-processor systems.

  9. Modeling tsunami damage in Aceh: a reply

    Treesearch

    Louis R. Iverson; Anantha M. Prasad

    2008-01-01

    In reply to the critique of Baird and Kerr, we emphasize that our model is a generalized vulnerability model, built from easily acquired data from anywhere in the world, to identify areas with probable susceptibility to large tsunamis--and discuss their other criticisms in detail. We also show that a rejection of the role of trees in helping protect vulnerable areas is...

  10. Contribution of Asteroid Generated Tsunami to the Impact Hazard

    NASA Technical Reports Server (NTRS)

    Morrison, David; Venkatapathy, Ethiraj

    2017-01-01

    The long-standing uncertainty about the importance of asteroid-generated tsunami was addressed at a workshop in August 2016, co-sponsored by NASA and NOAA. Experts from NASA, NOAA, the DoE tri-labs (LLNL, SNL, and LANL), DHS, FEMA, and academia addressed the hazard of tsunami created by asteroid impacts, focusing primarily on NEAs with diameter less than 250m. Participants jointly identified key issues and shared information for nearly a year to coordinate their results for discussion at the workshop. They used modern computational tools to examine 1) Near-field wave generation by the impact; 2) Long-distance wave propagation; 3) Damage from coastal run-up and inundation, and associated hazard. The workshop resulted in broad consensus that the asteroid impact tsunami threat is not as great as previously thought.

  11. Sensitivity study of the Storegga Slide tsunami using retrogressive and visco-plastic rheology models

    NASA Astrophysics Data System (ADS)

    Kim, Jihwan; Løvholt, Finn

    2016-04-01

    Enormous submarine landslides having volumes up to thousands of km3 and long run-out may cause tsunamis with widespread effects. Clay-rich landslides, such as Trænadjupet and Storegga offshore Norway commonly involve retrogressive mass and momentum release mechanisms that affect the tsunami generation. As a consequence, the failure mechanisms, soil parameters, and release rate of the retrogression are of importance for the tsunami generation. Previous attempts to model the tsunami generation due to retrogressive landslides are few, and limited to idealized conditions. Here, a visco-plastic model including additional effects such as remolding, time dependent mass release, and hydrodynamic resistance, is employed for simulating the Storegga Slide. As landslide strength parameters and their evolution in time are uncertain, it is necessary to conduct a sensitivity study to shed light on the tsunamigenic processes. The induced tsunami is simulated using Geoclaw. We also compare our tsunami simulations with recent analysis conducted using a pure retrogressive model for the landslide, as well as previously published results using a block model. The availability of paleotsunami run-up data and detailed slide deposits provides a suitable background for improved understanding of the slide mechanics and tsunami generation. The research leading to these results has received funding from the Research Council of Norway under grant number 231252 (Project TsunamiLand) and the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement 603839 (Project ASTARTE).

  12. Near Field Modeling for the Maule Tsunami from DART, GPS and Finite Fault Solutions (Invited)

    NASA Astrophysics Data System (ADS)

    Arcas, D.; Chamberlin, C.; Lagos, M.; Ramirez-Herrera, M.; Tang, L.; Wei, Y.

    2010-12-01

    The earthquake and tsunami of February, 27, 2010 in central Chile has rekindled an interest in developing techniques to predict the impact of near field tsunamis along the Chilean coastline. Following the earthquake, several initiatives were proposed to increase the density of seismic, pressure and motion sensors along the South American trench, in order to provide field data that could be used to estimate tsunami impact on the coast. However, the precise use of those data in the elaboration of a quantitative assessment of coastal tsunami damage has not been clarified. The present work makes use of seismic, Deep-ocean Assessment and Reporting of Tsunamis (DART®) systems, and GPS measurements obtained during the Maule earthquake to initiate a number of tsunami inundation models along the rupture area by expressing different versions of the seismic crustal deformation in terms of NOAA’s tsunami unit source functions. Translation of all available real-time data into a feasible tsunami source is essential in near-field tsunami impact prediction in which an impact assessment must be generated under very stringent time constraints. Inundation results from each different source are then contrasted with field and tide gauge data by comparing arrival time, maximum wave height, maximum inundation and tsunami decay rate, using field data collected by the authors.

  13. A comparison between two inundation models for the 25 Ooctober 2010 Mentawai Islands Tsunami

    NASA Astrophysics Data System (ADS)

    Huang, Z.; Borrero, J. C.; Qiu, Q.; Hill, E. M.; Li, L.; Sieh, K. E.

    2011-12-01

    On 25 October 2010, an Mw~7.8 earthquake occurred on the Sumatra megathrust seaward of the Mentawai Islands, Indonesia, generating a tsunami which killed approximately 500 people. Following the event, the Earth Observatory of Singapore (EOS) initiated a post-tsunami field survey, collecting tsunami run-up data from more than 30 sites on Pagai Selatan, Pagai Utara and Sipora. The strongest tsunami effects were observed on several small islands offshore of Pagai Selatan, where runup exceeded 16 m. This presentation will focus on a detailed comparison between two tsunami propagation and inundation models: COMCOT (Cornell Multi-grid Coupled Tsunami model) and MOST (Method of Splitting Tsunami). Simulations are initialized using fault models based on data from a 1-hz GPS system that measured co-seismic deformation throughout the region. Preliminary simulations suggest that 2-m vertical seafloor deformation over a reasonably large area is required to recreate most of the observed tsunami effects. Since the GPS data suggest that subsidence of the islands is small, this implies that the tsunami source region is somewhat narrower and located further offshore than described in recently published earthquake source models based on teleseismic inversions alone. We will also discuss issues such as bathymetric and topographic data preparation and the uncertainty in the modeling results due to the lack of high resolution bathymetry and topography in the study area.

  14. Tsunami geology in paleoseismology

    USGS Publications Warehouse

    Yuichi Nishimura,; Jaffe, Bruce E.

    2015-01-01

    The 2004 Indian Ocean and 2011 Tohoku-oki disasters dramatically demonstrated the destructiveness and deadliness of tsunamis. For the assessment of future risk posed by tsunamis it is necessary to understand past tsunami events. Recent work on tsunami deposits has provided new information on paleotsunami events, including their recurrence interval and the size of the tsunamis (e.g. [187–189]). Tsunamis are observed not only on the margin of oceans but also in lakes. The majority of tsunamis are generated by earthquakes, but other events that displace water such as landslides and volcanic eruptions can also generate tsunamis. These non-earthquake tsunamis occur less frequently than earthquake tsunamis; it is, therefore, very important to find and study geologic evidence for past eruption and submarine landslide triggered tsunami events, as their rare occurrence may lead to risks being underestimated. Geologic investigations of tsunamis have historically relied on earthquake geology. Geophysicists estimate the parameters of vertical coseismic displacement that tsunami modelers use as a tsunami's initial condition. The modelers then let the simulated tsunami run ashore. This approach suffers from the relationship between the earthquake and seafloor displacement, the pertinent parameter in tsunami generation, being equivocal. In recent years, geologic investigations of tsunamis have added sedimentology and micropaleontology, which focus on identifying and interpreting depositional and erosional features of tsunamis. For example, coastal sediment may contain deposits that provide important information on past tsunami events [190, 191]. In some cases, a tsunami is recorded by a single sand layer. Elsewhere, tsunami deposits can consist of complex layers of mud, sand, and boulders, containing abundant stratigraphic evidence for sediment reworking and redeposition. These onshore sediments are geologic evidence for tsunamis and are called ‘tsunami deposits’ (Figs. 26

  15. Modelling of historical tsunami in Eastern Indonesia: 1674 Ambon and 1992 Flores case studies

    NASA Astrophysics Data System (ADS)

    Pranantyo, Ignatius Ryan; Cummins, Phil; Griffin, Jonathan; Davies, Gareth; Latief, Hamzah

    2017-07-01

    In order to reliably assess tsunami hazard in eastern Indonesia, we need to understand how historical events were generated. Here we consider two such events: the 1674 Ambon and the 1992 Flores tsunamis. Firstly, Ambon Island suffered a devastating earthquake that generated a tsunami with 100 m run-up height on the north coast of the island in 1674. However, there is no known active fault around the island capable of generating such a gigantic wave. Rumphius' report describes that the initial wave was coming from three villages that collapsed immediately after the earthquake with width as far as a musket shot. Moreover, a very high tsunami was only observed locally. We suspect that a submarine landslide was the main cause of the gigantic tsunami on the north side of Ambon Island. Unfortunately, there is no data available to confirm if landslide have occurred in this region. Secondly, several tsunami source models for the 1992 Flores event have been suggested. However, the fault strike is quite different compare to the existing Flores back-arc thrust and has not been well validated against a tide gauge waveform at Palopo, Sulawesi. We considered a tsunami model based on Griffin, et al., 2015, extended with high resolution bathymetry laround Palopo, in order to validate the latest tsunami source model available. In general, the model produces a good agreement with tsunami waveforms, but arrives 10 minutes late compared to observed data. In addition, the source overestimates the tsunami inundation west of Maumere, and does not account for the presumed landslide tsunami on the east side of Flores Island.

  16. Generation, propagation and run-up of tsunamis due to the Chicxulub impact event

    NASA Astrophysics Data System (ADS)

    Weisz, R.; Wuennenmann, K.; Bahlburg, H.

    2003-04-01

    The Chicxulub impact event can be investigated in (1) local, (2) regional and in (3) global scales. Our investigations focus on the regional scale, especially on the influence of tsunami waves on the coast around the Gulf of Mexico caused by the impact. During an impact two types of tsunamis are generated. The first wave is known as the "rim wave" and is generated in front of the ejecta curtain. The second one is linked to the late modification stage of the impact and results from the collapsing cavity of water. We designate this wave as "collapse wave". The "rim wave" and "collapse wave" are able to propagate over long distances, without a significant loss of wave amplitude. Corresponding to the amplitudes, the waves have a potentially large influence on the coastal areas. Run-up distance and run-up height can be used as parameters for describing this influence. We are utilizing a multimaterial hydrocode (SALE) to simulate the generation of tsunami waves. The propagation of the waves is based on the non-linear shallow water theory, because tsunami waves are defined to be long waves. The position of the coast line varies according to the tsunami run-up and is implemented with open boundary conditions. We show with our investigations (1) the generation of tsunami waves due to shallow water impacts, (2) wave damping during propagation, and (3) the influence of the "rim wave" and the "collapse wave" on the coastal areas. Here, we present our first results from numerical modeling of tsunami waves owing to a Chicxulub sized impactor. The characteristics of the “rim wave” depend on the size of the bolide and the water depth. However, the amplitude and velocity of the “collapse wave” is only determined by the water depth in the impact area. The numerical modeling of the tsunami propagation and run-up is calculated along a section from the impact point towards to the west and gives the moderate damping of both waves and the run-up on the coastal area. As a first

  17. Advanced Tsunami Numerical Simulations and Energy Considerations by use of 3D-2D Coupled Models: The October 11, 1918, Mona Passage Tsunami

    NASA Astrophysics Data System (ADS)

    López-Venegas, Alberto M.; Horrillo, Juan; Pampell-Manis, Alyssa; Huérfano, Victor; Mercado, Aurelio

    2015-06-01

    The most recent tsunami observed along the coast of the island of Puerto Rico occurred on October 11, 1918, after a magnitude 7.2 earthquake in the Mona Passage. The earthquake was responsible for initiating a tsunami that mostly affected the northwestern coast of the island. Runup values from a post-tsunami survey indicated the waves reached up to 6 m. A controversy regarding the source of the tsunami has resulted in several numerical simulations involving either fault rupture or a submarine landslide as the most probable cause of the tsunami. Here we follow up on previous simulations of the tsunami from a submarine landslide source off the western coast of Puerto Rico as initiated by the earthquake. Improvements on our previous study include: (1) higher-resolution bathymetry; (2) a 3D-2D coupled numerical model specifically developed for the tsunami; (3) use of the non-hydrostatic numerical model NEOWAVE (non-hydrostatic evolution of ocean WAVE) featuring two-way nesting capabilities; and (4) comprehensive energy analysis to determine the time of full tsunami wave development. The three-dimensional Navier-Stokes model tsunami solution using the Navier-Stokes algorithm with multiple interfaces for two fluids (water and landslide) was used to determine the initial wave characteristic generated by the submarine landslide. Use of NEOWAVE enabled us to solve for coastal inundation, wave propagation, and detailed runup. Our results were in agreement with previous work in which a submarine landslide is favored as the most probable source of the tsunami, and improvement in the resolution of the bathymetry yielded inundation of the coastal areas that compare well with values from a post-tsunami survey. Our unique energy analysis indicates that most of the wave energy is isolated in the wave generation region, particularly at depths near the landslide, and once the initial wave propagates from the generation region its energy begins to stabilize.

  18. Modelling of Charles Darwin's tsunami reports

    NASA Astrophysics Data System (ADS)

    Galiev, Shamil

    2010-05-01

    -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.

  19. The July 17, 2006 Java Tsunami: Tsunami Modeling and the Probable Causes of the Extreme Run-up

    NASA Astrophysics Data System (ADS)

    Kongko, W.; Schlurmann, T.

    2009-04-01

    On 17 July 2006, an Earthquake magnitude Mw 7.8 off the south coast of west Java, Indonesia generated tsunami that affected over 300 km of south Java coastline and killed more than 600 people. Observed tsunami heights and field measurement of run-up distributions were uniformly scattered approximately 5 to 7 m along a 200 km coastal stretch; remarkably, a locally focused tsunami run-up height exceeding 20 m at Nusakambangan Island has been observed. Within the framework of the German Indonesia Tsunami Early Warning System (GITEWS) Project, a high-resolution near-shore bathymetrical survey equipped by multi-beam echo-sounder has been recently conducted. Additional geodata have been collected using Intermap Technologies STAR-4 airborne interferometric SAR data acquisition system on a 5 m ground sample distance basis in order to establish a most-sophisticated Digital Terrain Model (DTM). This paper describes the outcome of tsunami modelling approaches using high resolution data of bathymetry and topography being part of a general case study in Cilacap, Indonesia, and medium resolution data for other area along coastline of south Java Island. By means of two different seismic deformation models to mimic the tsunami source generation, a numerical code based on the 2D nonlinear shallow water equations is used to simulate probable tsunami run-up scenarios. Several model tests are done and virtual points in offshore, near-shore, coastline, as well as tsunami run-up on the coast are collected. For the purpose of validation, the model results are compared with field observations and sea level data observed at several tide gauges stations. The performance of numerical simulations and correlations with observed field data are highlighted, and probable causes for the extreme wave heights and run-ups are outlined. References Ammon, C.J., Kanamori, K., Lay, T., and Velasco, A., 2006. The July 2006 Java Tsunami Earthquake, Geophysical Research Letters, 33(L24308). Fritz, H

  20. Tsunami Simulators in Physical Modelling Laboratories - From Concept to Proven Technique

    NASA Astrophysics Data System (ADS)

    Allsop, W.; Chandler, I.; Rossetto, T.; McGovern, D.; Petrone, C.; Robinson, D.

    2016-12-01

    Before 2004, there was little public awareness around Indian Ocean coasts of the potential size and effects of tsunami. Even in 2011, the scale and extent of devastation by the Japan East Coast Tsunami was unexpected. There were very few engineering tools to assess onshore impacts of tsunami, so no agreement on robust methods to predict forces on coastal defences, buildings or related infrastructure. Modelling generally used substantial simplifications of either solitary waves (far too short durations) or dam break (unrealistic and/or uncontrolled wave forms).This presentation will describe research from EPI-centre, HYDRALAB IV, URBANWAVES and CRUST projects over the last 10 years that have developed and refined pneumatic Tsunami Simulators for the hydraulic laboratory. These unique devices have been used to model generic elevated and N-wave tsunamis up to and over simple shorelines, and at example defences. They have reproduced full-duration tsunamis including the Mercator trace from 2004 at 1:50 scale. Engineering scale models subjected to those tsunamis have measured wave run-up on simple slopes, forces on idealised sea defences and pressures / forces on buildings. This presentation will describe how these pneumatic Tsunami Simulators work, demonstrate how they have generated tsunami waves longer than the facility within which they operate, and will highlight research results from the three generations of Tsunami Simulator. Of direct relevance to engineers and modellers will be measurements of wave run-up levels and comparison with theoretical predictions. Recent measurements of forces on individual buildings have been generalized by separate experiments on buildings (up to 4 rows) which show that the greatest forces can act on the landward (not seaward) buildings. Continuing research in the 70m long 4m wide Fast Flow Facility on tsunami defence structures have also measured forces on buildings in the lee of a failed defence wall.

  1. Generation of realistic tsunami waves using a bottom-tilting wave maker

    NASA Astrophysics Data System (ADS)

    Park, Yong Sung; Hwang, Jin Hwan

    2016-11-01

    Tsunamis have caused more than 260,000 human losses and 250 billion in damage worldwide in the last ten years. Observations made during 2011 Japan Tohoku Tsunami revealed that the commonly used waves (solitary waves) to model tsunamis are at least an order-of-magnitude shorter than the real tsunamis, which calls for re-evaluation of the current understanding of tsunamis. To prompt the required paradigm shift, a new wave generator, namely the bottom-tilting wave generator, has been developed at the University of Dundee. The wave tank is fitted with an adjustable slope and a bottom flap hinged at the beginning of the slope. By moving the bottom flap up and down, we can generate very long waves. Here we will report characteristics of waves generated by simple bottom motions, either moving it upward or downward from an initial displacement ending it being horizontal. Two parameters, namely the initial displacement of the bottom and the speed of the motion, determine characteristics of the generated waves. Wave amplitudes scale well with the volume flux of the displaced water. On the other hand, due to combined effects of nonlinearity and dispersion, wavelengths show more complicated relationship with the two bottom motion parameters. We will also demonstrate that by combining simple up and down motions, it is possible to generate waves resembling the one measured during 2011 tsunami. YSP acknowledges financial support from the Royal Society of Edinburgh through the Royal Society of Edinburgh and Scottish Government Personal Research Fellowship Co-Funded by the Marie-Curie Actions.

  2. Tsunami Hockey

    NASA Astrophysics Data System (ADS)

    Weinstein, S.; Becker, N. C.; Wang, D.; Fryer, G. J.

    2013-12-01

    An important issue that vexes tsunami warning centers (TWCs) is when to cancel a tsunami warning once it is in effect. Emergency managers often face a variety of pressures to allow the public to resume their normal activities, but allowing coastal populations to return too quickly can put them at risk. A TWC must, therefore, exercise caution when cancelling a warning. Kim and Whitmore (2013) show that in many cases a TWC can use the decay of tsunami oscillations in a harbor to forecast when its amplitudes will fall to safe levels. This technique should prove reasonably robust for local tsunamis (those that are potentially dangerous within only 100 km of their source region) and for regional tsunamis (whose danger is limited to within 1000km of the source region) as well. For ocean-crossing destructive tsunamis such as the 11 March 2011 Tohoku tsunami, however, this technique may be inadequate. When a tsunami propagates across the ocean basin, it will encounter topographic obstacles such as seamount chains or coastlines, resulting in coherent reflections that can propagate great distances. When these reflections reach previously-impacted coastlines, they can recharge decaying tsunami oscillations and make them hazardous again. Warning center scientists should forecast sea-level records for 24 hours beyond the initial tsunami arrival in order to observe any potential reflections that may pose a hazard. Animations are a convenient way to visualize reflections and gain a broad geographic overview of their impacts. The Pacific Tsunami Warning Center has developed tools based on tsunami simulations using the RIFT tsunami forecast model. RIFT is a linear, parallelized numerical tsunami propagation model that runs very efficiently on a multi-CPU system (Wang et al, 2012). It can simulate 30-hours of tsunami wave propagation in the Pacific Ocean at 4 arc minute resolution in approximately 6 minutes of real time on a 12-CPU system. Constructing a 30-hour animation using 1

  3. Speeding up tsunami wave propagation modeling

    NASA Astrophysics Data System (ADS)

    Lavrentyev, Mikhail; Romanenko, Alexey

    2014-05-01

    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.

  4. Duration of Tsunami Generation Longer than Duration of Seismic Wave Generation in the 2011 Mw 9.0 Tohoku-Oki Earthquake

    NASA Astrophysics Data System (ADS)

    Fujihara, S.; Korenaga, M.; Kawaji, K.; Akiyama, S.

    2013-12-01

    We try to compare and evaluate the nature of tsunami generation and seismic wave generation in occurrence of the 2011 Tohoku-Oki earthquake (hereafter, called as TOH11), in terms of two type of moment rate functions, inferred from finite source imaging of tsunami waveforms and seismic waveforms. Since 1970's, the nature of "tsunami earthquakes" has been discussed in many researches (e.g. Kanamori, 1972; Kanamori and Kikuchi, 1993; Kikuchi and Kanamori, 1995; Ide et al., 1993; Satake, 1994) mostly based on analysis of seismic waveform data , in terms of the "slow" nature of tsunami earthquakes (e.g., the 1992 Nicaragura earthquake). Although TOH11 is not necessarily understood as a tsunami earthquake, TOH11 is one of historical earthquakes that simultaneously generated large seismic waves and tsunami. Also, TOH11 is one of earthquakes which was observed both by seismic observation network and tsunami observation network around the Japanese islands. Therefore, for the purpose of analyzing the nature of tsunami generation, we try to utilize tsunami waveform data as much as possible. In our previous studies of TOH11 (Fujihara et al., 2012a; Fujihara et al., 2012b), we inverted tsunami waveforms at GPS wave gauges of NOWPHAS to image the spatio-temporal slip distribution. The "temporal" nature of our tsunami source model is generally consistent with the other tsunami source models (e.g., Satake et al, 2013). For seismic waveform inversion based on 1-D structure, here we inverted broadband seismograms at GSN stations based on the teleseismic body-wave inversion scheme (Kikuchi and Kanamori, 2003). Also, for seismic waveform inversion considering the inhomogeneous internal structure, we inverted strong motion seismograms at K-NET and KiK-net stations, based on 3-D Green's functions (Fujihara et al., 2013a; Fujihara et al., 2013b). The gross "temporal" nature of our seismic source models are generally consistent with the other seismic source models (e.g., Yoshida et al

  5. Benchmarking an Unstructured-Grid Model for Tsunami Current Modeling

    NASA Astrophysics Data System (ADS)

    Zhang, Yinglong J.; Priest, George; Allan, Jonathan; Stimely, Laura

    2016-12-01

    We present model results derived from a tsunami current benchmarking workshop held by the NTHMP (National Tsunami Hazard Mitigation Program) in February 2015. Modeling was undertaken using our own 3D unstructured-grid model that has been previously certified by the NTHMP for tsunami inundation. Results for two benchmark tests are described here, including: (1) vortex structure in the wake of a submerged shoal and (2) impact of tsunami waves on Hilo Harbor in the 2011 Tohoku event. The modeled current velocities are compared with available lab and field data. We demonstrate that the model is able to accurately capture the velocity field in the two benchmark tests; in particular, the 3D model gives a much more accurate wake structure than the 2D model for the first test, with the root-mean-square error and mean bias no more than 2 cm s-1 and 8 mm s-1, respectively, for the modeled velocity.

  6. The Chile tsunami of 27 February 2010: Field survey and modeling

    NASA Astrophysics Data System (ADS)

    Fritz, H. M.; Petroff, C. M.; Catalan, P. A.; Cienfuegos, R.; Winckler, P.; Kalligeris, N.; Weiss, R.; Meneses, G.; Valderas-Bermejo, C.; Barrientos, S. E.; Ebeling, C. W.; Papadopoulos, A.; Contreras, M.; Almar, R.; Dominguez, J.; Synolakis, C.

    2011-12-01

    between Caleta Chome and Punta Morguilla. More than 2 m vertical uplift were measured on Santa Maria Island. Tsunami propagation in the Pacific Ocean is simulated using the benchmarked tsunami model MOST (Titov and Gonzalez, 1997; Titov and Synolakis, 1998). For initial conditions the inversion model of Lorito et al. (2011) is utilized. The model results highlight the directivity of the highest tsunami waves towards Juan Fernández and Easter Island during the transoceanic propagation. The team interviewed numerous eyewitnesses and educated residents about tsunami hazards since community-based education and awareness programs are essential to save lives in locales at risk from locally generated tsunamis.

  7. Hydraulic experiment on formation mechanism of tsunami deposit and verification of sediment transport model for tsunamis

    NASA Astrophysics Data System (ADS)

    Yamamoto, A.; Takahashi, T.; Harada, K.; Sakuraba, M.; Nojima, K.

    2017-12-01

    An underestimation of the 2011 Tohoku tsunami caused serious damage in coastal area. Reconsideration for tsunami estimation needs knowledge of paleo tsunamis. The historical records of giant tsunamis are limited, because they had occurred infrequently. Tsunami deposits may include many of tsunami records and are expected to analyze paleo tsunamis. However, present research on tsunami deposits are not able to estimate the tsunami source and its magnitude. Furthermore, numerical models of tsunami and its sediment transport are also important. Takahashi et al. (1999) proposed a model of movable bed condition due to tsunamis, although it has some issues. Improvement of the model needs basic data on sediment transport and deposition. This study investigated the formation mechanism of tsunami deposit by hydraulic experiment using a two-dimensional water channel with slope. In a fixed bed condition experiment, velocity, water level and suspended load concentration were measured at many points. In a movable bed condition, effects of sand grains and bore wave on the deposit were examined. Yamamoto et al. (2016) showed deposition range varied with sand grain sizes. In addition, it is revealed that the range fluctuated by number of waves and wave period. The measurements of velocity and water level showed that flow was clearly different near shoreline and in run-up area. Large velocity by return flow was affected the amount of sand deposit near shoreline. When a cutoff wall was installed on the slope, the amount of sand deposit repeatedly increased and decreased. Especially, sand deposit increased where velocity decreased. Takahashi et al. (1999) adapted the proposed model into Kesennuma bay when the 1960 Chilean tsunami arrived, although the amount of sand transportation was underestimated. The cause of the underestimation is inferred that the velocity of this model was underestimated. A relationship between velocity and sediment transport has to be studied in detail, but

  8. Impact-generated Tsunamis: An Over-rated Hazard

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.

    2003-01-01

    A number of authors have suggested that oceanic waves (tsunami) created by the impact of relatively small asteroids into the Earth's oceans might cause widespread devastation to coastal cities. If correct, this suggests that asteroids > 100 m in diameter may pose a serious hazard to humanity and could require a substantial expansion of the current efforts to identify earth-crossing asteroids > 1 km in diameter. The debate on this hazard was recently altered by the release of a document previously inaccessible to the scientific community. In 1968 the US Office of Naval Research commissioned a summary of several decades of research into the hazard proposed by waves generated by nuclear explosions in the ocean. Authored by tsunami expert William Van Dorn, this 173-page report entitled Handbook of Explosion-Generated Water Waves affords new insight into the process of impact wave formation, propagation, and run up onto the shoreline.

  9. Tsunami propagation modelling - a sensitivity study

    NASA Astrophysics Data System (ADS)

    Dao, M. H.; Tkalich, P.

    2007-12-01

    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.

  10. Numerical experiment on tsunami deposit distribution process by using tsunami sediment transport model in historical tsunami event of megathrust Nankai trough earthquake

    NASA Astrophysics Data System (ADS)

    Imai, K.; Sugawara, D.; Takahashi, T.

    2017-12-01

    A large flow caused by tsunami transports sediments from beach and forms tsunami deposits in land and coastal lakes. A tsunami deposit has been found in their undisturbed on coastal lakes especially. Okamura & Matsuoka (2012) found some tsunami deposits in the field survey of coastal lakes facing to the Nankai trough, and tsunami deposits due to the past eight Nankai Trough megathrust earthquakes they identified. The environment in coastal lakes is stably calm and suitable for tsunami deposits preservation compared to other topographical conditions such as plains. Therefore, there is a possibility that the recurrence interval of megathrust earthquakes and tsunamis will be discussed with high resolution. In addition, it has been pointed out that small events that cannot be detected in plains could be separated finely (Sawai, 2012). Various aspects of past tsunami is expected to be elucidated, in consideration of topographical conditions of coastal lakes by using the relationship between the erosion-and-sedimentation process of the lake bottom and the external force of tsunami. In this research, numerical examination based on tsunami sediment transport model (Takahashi et al., 1999) was carried out on the site Ryujin-ike pond of Ohita, Japan where tsunami deposit was identified, and deposit migration analysis was conducted on the tsunami deposit distribution process of historical Nankai Trough earthquakes. Furthermore, examination of tsunami source conditions is possibly investigated by comparison studies of the observed data and the computation of tsunami deposit distribution. It is difficult to clarify details of tsunami source from indistinct information of paleogeographical conditions. However, this result shows that it can be used as a constraint condition of the tsunami source scale by combining tsunami deposit distribution in lakes with computation data.

  11. Spatial modelling for tsunami evacuation route in Parangtritis Village

    NASA Astrophysics Data System (ADS)

    Juniansah, A.; Tyas, B. I.; Tama, G. C.; Febriani, K. R.; Farda, N. M.

    2018-04-01

    Tsunami is a series of huge sea waves that commonly occurs because of the oceanic plate movement or tectonic activity under the sea. As a sudden hazard, the tsunami has damaged many people over the years. Parangtritis village is one of high tsunami hazard risk area in Indonesia which needs an effective tsunami risk reduction. This study aims are modelling a tsunami susceptibility map, existing assembly points evaluation, and suggesting effective evacuation routes. The susceptibility map was created using ALOS PALSAR DEM and surface roughness coefficient. The method of tsunami modelling employed inundation model developed by Berryman (2006). The results are used to determine new assembly points based on the Sentinel 2A imagery and to determine the most effective evacuation route by using network analyst. This model can be used to create detailed scale of evacuation route, but unrepresentative for assembly point that far from road network.

  12. Post-eruptive flooding of Santorini caldera and implications for tsunami generation

    NASA Astrophysics Data System (ADS)

    Nomikou, Paraskevi; Druitt, Tim; Hübscher, Christian; Mather, Tamsin; Paulatto, Michele; Kalnins, Lara; Kelfoun, Karim; Papanikolaou, Dimitris; Bejelou, Konstantina; Lampridou, Danai; Pyle, David; Carey, Steven; Watts, Anthony; Weiß, Benedikt; Parks, Michelle

    2017-04-01

    Caldera-forming eruptions of island volcanoes generate tsunamis by the interaction of different eruptive phenomena with the sea. Such tsunamis are a major hazard, but forward models of their impacts are limited by poor understanding of source mechanisms. The eruption of Santorini 3600 years ago was one of the largest of eruptions known worldwide from the past 10,000 years - and was at least 3 times larger than the catastrophic eruption of Krakatoa. This huge eruption evacuated large volumes of magma, causing collapse of the large caldera, which is now filled with seawater. Tsunamis from this eruption have been proposed to have played a role in the demise of the Minoan culture across the southern Aegean, through damage to coastal towns, harbors, shipping and maritime trade. Before the eruption, there was an older caldera in the northern part of Santorini, partly filled with a shallow lagoon. In our study, we present bathymetric and seismic evidence showing that the caldera was not open to the sea during the main phase of the eruption, but was flooded once the eruption had finished. Following subsidence of the caldera floor, rapid inflow of seawater and landslides cut a deep 2.0-2.5 km3 submarine channel into the northern flank of the caldera wall. Hydrodynamic modelling indicates that the caldera was flooded through this breach in less than a couple of days. It was previously proposed that collapse of the caldera could have led to the formation of a major tsunami; but this is ruled out by our new evidence. Any tsunami's generated were most likely caused by entry of pyroclastic flows into the sea, combined with slumping of submarine pyroclastic accumulations. This idea is consistent with previous assertions that pyroclastic flows were the main cause of tsunamis at Krakatau.

  13. Modeling potential tsunami sources for deposits near Unalaska Island, Aleutian Islands

    NASA Astrophysics Data System (ADS)

    La Selle, S.; Gelfenbaum, G. R.

    2013-12-01

    In regions with little seismic data and short historical records of earthquakes, we can use preserved tsunami deposits and tsunami modeling to infer if, when and where tsunamigenic earthquakes have occurred. The Aleutian-Alaska subduction zone in the region offshore of Unalaska Island is one such region where the historical and paleo-seismicity is poorly understood. This section of the subduction zone is not thought to have ruptured historically in a large earthquake, leading some to designate the region as a seismic gap. By modeling various historical and synthetic earthquake sources, we investigate whether or not tsunamis that left deposits near Unalaska Island were generated by earthquakes rupturing through Unalaska Gap. Preliminary field investigations near the eastern end of Unalaska Island have identified paleotsunami deposits well above sea level, suggesting that multiple tsunamis in the last 5,000 years have flooded low-lying areas over 1 km inland. Other indicators of tsunami inundation, such as a breached cobble beach berm and driftwood logs stranded far inland, were tentatively attributed to the March 9, 1957 tsunami, which had reported runup of 13 to 22 meters on Umnak and Unimak Islands, to the west and east of Unalaska. In order to determine if tsunami inundation could have reached the runup markers observed on Unalaska, we modeled the 1957 tsunami using GeoCLAW, a numerical model that simulates tsunami generation, propagation, and inundation. The published rupture orientation and slip distribution for the MW 8.6, 1957 earthquake (Johnson et al., 1994) was used as the tsunami source, which delineates a 1200 km long rupture zone along the Aleutian trench from Delarof Island to Unimak Island. Model results indicate that runup and inundation from this particular source are too low to account for the runup markers observed in the field, because slip is concentrated in the western half of the rupture zone, far from Unalaska. To ascertain if any realistic

  14. 2011 Great East Japan tsunami in Okhotsk Sea region: numerical modelings and observation data

    NASA Astrophysics Data System (ADS)

    Kostenko, Irina; Zaytsev, Andrey; Yalciner, Ahmet; Pelinovsky, Efim

    2013-04-01

    The 11 March, 2011 Great East Japan Earthquake with Mw: 9.0 occurred at 05:46:23 UTC with its epicenter estimated at 38.322_N, 142.369_E, and focal depth of 32 km (USGS, 2011). Tsunami waves propagated in Pacific Ocean to all directions. At Russian coast the highest waves were observed in the Kuril Islands (Malokurilskoye, Kunashir Island) which located in between Pacific ocean and the Okhotsk Sea. Kuril island provides limited transmission of tsunami waves from Pacific ocean. tsunami In 2011 Great East Japan Earthquake and Tsunami event, the maximum amplitude of the tsunami was observed as 3 m in Kuril islands. However, tsunami arrived Okhotsk Sea losing a significant amount of energy. Therefore the tsunami amplitudes at the coast of the Okhotsk Sea were smaller. In order to estimate the level of energy loss while passing through the narrow straits of the Kuril Islands, a series of numerical simulations was done by using tsunami numerical code NAMI DANCE. Ten largest earthquake shocks capable of generating tsunami were used as inputs of tsunami sources in the modeling. Hence the relation between the transmission of tsunami and the dimensions of the straits are compared and discussed. Finally the characteristics of tsunami propagation (arrival time and coastal amplification) at the coast in the Okhotsk Sea. The varying grid structure is used in numerical modeling in order to make finer analysis of tsunami passing through narrow straits of the Kuril Islands. This allows to combine exactly the installation locations of stationary and computational gauges. The simulation results are compared with the observations. The linear form of shallow water equations are used in the deep ocean region offshore part of the Sea of Okhotsk. Boussinesq type equations were also used at the near shore area in simulations. Since the Okhotsk Sea Results are a semi enclosed basin, the reflection characteristics at the coastal boundaries may be important. The numerical experiments are also

  15. Tsunami Waves Joint Inversion Using Tsunami Inundation, Tsunami Deposits Distribution and Marine-Terrestrial Sediment Signal in Tsunami Deposit

    NASA Astrophysics Data System (ADS)

    Tang, H.; WANG, J.

    2017-12-01

    Population living close to coastlines is increasing, which creates higher risks due to coastal hazards, such as the tsunami. However, the generation of a tsunami is not fully understood yet, especially for paleo-tsunami. Tsunami deposits are one of the concrete evidence in the geological record which we can apply for studying paleo-tsunami. The understanding of tsunami deposits has significantly improved over the last decades. There are many inversion models (e.g. TsuSedMod, TSUFLIND, and TSUFLIND-EnKF) to study the overland-flow characteristics based on tsunami deposits. However, none of them tries to reconstruct offshore tsunami wave characteristics (wave form, wave height, and length) based on tsunami deposits. Here we present a state-of-the-art inverse approach to reconstruct offshore tsunami wave based on the tsunami inundation data, the spatial distribution of tsunami deposits and Marine-terrestrial sediment signal in the tsunami deposits. Ensemble Kalman Filter (EnKF) Method is used for assimilating both sediment transport simulations and the field observation data. While more computationally expensive, the EnKF approach potentially provides more accurate reconstructions for tsunami waveform. In addition to the improvement of inversion results, the ensemble-based method can also quantify the uncertainties of the results. Meanwhile, joint inversion improves the resolution of tsunami waves compared with inversions using any single data type. The method will be tested by field survey data and gauge data from the 2011 Tohoku tsunami on Sendai plain area.

  16. Odessa Tsunami of 27 June 2014: Observations and Numerical Modelling

    NASA Astrophysics Data System (ADS)

    Šepić, Jadranka; Rabinovich, Alexander B.; Sytov, Victor N.

    2018-04-01

    On 27 June, a 1-2-m high wave struck the beaches of Odessa, the third largest Ukrainian city, and the neighbouring port-town Illichevsk (northwestern Black Sea). Throughout the day, prominent seiche oscillations were observed in several other ports of the Black Sea. Tsunamigenic synoptic conditions were found over the Black Sea, stretching from Romania in the west to the Crimean Peninsula in the east. Intense air pressure disturbances and convective thunderstorm clouds were associated with these conditions; right at the time of the event, a 1.5-hPa air pressure jump was recorded at Odessa and a few hours earlier in Romania. We have utilized a barotropic ocean numerical model to test two hypotheses: (1) a tsunami-like wave was generated by an air pressure disturbance propagating directly over Odessa ("Experiment 1"); (2) a tsunami-like wave was generated by an air pressure disturbance propagating offshore, approximately 200 km to the south of Odessa, and along the shelf break ("Experiment 2"). Both experiments decisively confirm the meteorological origin of the tsunami-like waves on the coast of Odessa and imply that intensified long ocean waves in this region were generated via the Proudman resonance mechanism while propagating over the northwestern Black Sea shelf. The "Odessa tsunami" of 27 June 2014 was identified as a "beach meteotsunami", similar to events regularly observed on the beaches of Florida, USA, but different from the "harbour meteotsunamis", which occurred 1-3 days earlier in Ciutadella (Baleares, Spain), Mazara del Vallo (Sicily, Italy) and Vela Luka (Croatia) in the Mediterranean Sea, despite that they were associated with the same atmospheric system moving over the Mediterranean/Black Sea region on 23-27 June 2014.

  17. Rapid Determination of Appropriate Source Models for Tsunami Early Warning using a Depth Dependent Rigidity Curve: Method and Numerical Tests

    NASA Astrophysics Data System (ADS)

    Tanioka, Y.; Miranda, G. J. A.; Gusman, A. R.

    2017-12-01

    Recently, tsunami early warning technique has been improved using tsunami waveforms observed at the ocean bottom pressure gauges such as NOAA DART system or DONET and S-NET systems in Japan. However, for tsunami early warning of near field tsunamis, it is essential to determine appropriate source models using seismological analysis before large tsunamis hit the coast, especially for tsunami earthquakes which generated significantly large tsunamis. In this paper, we develop a technique to determine appropriate source models from which appropriate tsunami inundation along the coast can be numerically computed The technique is tested for four large earthquakes, the 1992 Nicaragua tsunami earthquake (Mw7.7), the 2001 El Salvador earthquake (Mw7.7), the 2004 El Astillero earthquake (Mw7.0), and the 2012 El Salvador-Nicaragua earthquake (Mw7.3), which occurred off Central America. In this study, fault parameters were estimated from the W-phase inversion, then the fault length and width were determined from scaling relationships. At first, the slip amount was calculated from the seismic moment with a constant rigidity of 3.5 x 10**10N/m2. The tsunami numerical simulation was carried out and compared with the observed tsunami. For the 1992 Nicaragua tsunami earthquake, the computed tsunami was much smaller than the observed one. For the 2004 El Astillero earthquake, the computed tsunami was overestimated. In order to solve this problem, we constructed a depth dependent rigidity curve, similar to suggested by Bilek and Lay (1999). The curve with a central depth estimated by the W-phase inversion was used to calculate the slip amount of the fault model. Using those new slip amounts, tsunami numerical simulation was carried out again. Then, the observed tsunami heights, run-up heights, and inundation areas for the 1992 Nicaragua tsunami earthquake were well explained by the computed one. The other tsunamis from the other three earthquakes were also reasonably well explained

  18. A Self-Consistent Fault Slip Model for the 2011 Tohoku Earthquake and Tsunami

    NASA Astrophysics Data System (ADS)

    Yamazaki, Yoshiki; Cheung, Kwok Fai; Lay, Thorne

    2018-02-01

    The unprecedented geophysical and hydrographic data sets from the 2011 Tohoku earthquake and tsunami have facilitated numerous modeling and inversion analyses for a wide range of dislocation models. Significant uncertainties remain in the slip distribution as well as the possible contribution of tsunami excitation from submarine slumping or anelastic wedge deformation. We seek a self-consistent model for the primary teleseismic and tsunami observations through an iterative approach that begins with downsampling of a finite fault model inverted from global seismic records. Direct adjustment of the fault displacement guided by high-resolution forward modeling of near-field tsunami waveform and runup measurements improves the features that are not satisfactorily accounted for by the seismic wave inversion. The results show acute sensitivity of the runup to impulsive tsunami waves generated by near-trench slip. The adjusted finite fault model is able to reproduce the DART records across the Pacific Ocean in forward modeling of the far-field tsunami as well as the global seismic records through a finer-scale subfault moment- and rake-constrained inversion, thereby validating its ability to account for the tsunami and teleseismic observations without requiring an exotic source. The upsampled final model gives reasonably good fits to onshore and offshore geodetic observations albeit early after-slip effects and wedge faulting that cannot be reliably accounted for. The large predicted slip of over 20 m at shallow depth extending northward to 39.7°N indicates extensive rerupture and reduced seismic hazard of the 1896 tsunami earthquake zone, as inferred to varying extents by several recent joint and tsunami-only inversions.

  19. Tsunami waves generated by dynamically triggered aftershocks of the 2010 Haiti earthquake

    NASA Astrophysics Data System (ADS)

    Ten Brink, U. S.; Wei, Y.; Fan, W.; Miller, N. C.; Granja, J. L.

    2017-12-01

    Dynamically-triggered aftershocks, thought to be set off by the passage of surface waves, are currently not considered in tsunami warnings, yet may produce enough seafloor deformation to generate tsunamis on their own, as judged from new findings about the January 12, 2010 Haiti earthquake tsunami in the Caribbean Sea. This tsunami followed the Mw7.0 Haiti mainshock, which resulted from a complex rupture along the north shore of Tiburon Peninsula, not beneath the Caribbean Sea. The mainshock, moreover, had a mixed strike-slip and thrust focal mechanism. There were no recorded aftershocks in the Caribbean Sea, only small coastal landslides and rock falls on the south shore of Tiburon Peninsula. Nevertheless, a tsunami was recorded on deep-sea DART buoy 42407 south of the Dominican Republic and on the Santo Domingo tide gauge, and run-ups of ≤3 m were observed along a 90-km-long stretch of the SE Haiti coast. Three dynamically-triggered aftershocks south of Haiti have been recently identified within the coda of the mainshock (<200 s) by analyzing P wave arrivals recorded by dense seismic arrays, parsing the arrivals into 20-s-long stacks, and back-projecting the arrivals to the vicinity of the main shock (50-300 km). Two of the aftershocks, coming 20-40 s and 40-60 s after the mainshock, plot along NW-SE-trending submarine ridges in the Caribbean Sea south of Haiti. The third event, 120-140 s was located along the steep eastern slope of Bahoruco Peninsula, which is delineated by a normal fault. Forward tsunami models show that the arrival times of the DART buoy and tide gauge times are best fit by the earliest of the three aftershocks, with a Caribbean source 60 km SW of the mainshock rupture zone. Preliminary inversion of the DART buoy time series for fault locations and orientations confirms the location of the first source, but requires an additional unidentified source closer to shore 40 km SW of the mainshock rupture zone. This overall agreement between

  20. Dynamic models of an earthquake and tsunami offshore Ventura, California

    USGS Publications Warehouse

    Kenny J. Ryan,; Geist, Eric L.; Barall, Michael; David D. Oglesby,

    2015-01-01

    The Ventura basin in Southern California includes coastal dip-slip faults that can likely produce earthquakes of magnitude 7 or greater and significant local tsunamis. We construct a 3-D dynamic rupture model of an earthquake on the Pitas Point and Lower Red Mountain faults to model low-frequency ground motion and the resulting tsunami, with a goal of elucidating the seismic and tsunami hazard in this area. Our model results in an average stress drop of 6 MPa, an average fault slip of 7.4 m, and a moment magnitude of 7.7, consistent with regional paleoseismic data. Our corresponding tsunami model uses final seafloor displacement from the rupture model as initial conditions to compute local propagation and inundation, resulting in large peak tsunami amplitudes northward and eastward due to site and path effects. Modeled inundation in the Ventura area is significantly greater than that indicated by state of California's current reference inundation line.

  1. Village Level Tsunami Threat Maps for Tamil Nadu, SE Coast of India: Numerical Modeling Technique

    NASA Astrophysics Data System (ADS)

    MP, J.; Kulangara Madham Subrahmanian, D.; V, R. M.

    2014-12-01

    The Indian Ocean tsunami (IOT) devastated several countries of North Indian Ocean. India is one of the worst affected countries after Indonesia and Sri Lanka. In India, Tamil Nadu suffered maximum with fatalities exceeding 8,000 people. Historical records show that tsunami has invaded the shores of Tamil Nadu in the past and has made people realize that the tsunami threat looms over Tamil Nadu and it is necessary to evolve strategies for tsunami threat management. The IOT has brought to light that tsunami inundation and runup varied within short distances and for the disaster management for tsunami, large scale maps showing areas that are likely to be affected by future tsunami are identified. Therefore threat assessment for six villages including Mamallapuram (also called Mahabalipuram) which is famous for its rock-cut temples, from the northern part of Tamil Nadu state of India has been carried out and threat maps categorizing the coast into areas of different degree of threat are prepared. The threat was assessed by numerical modeling using TUNAMI N2 code considering different tsunamigenic sources along the Andaman - Sumatra trench. While GEBCO and C-Map data was used for bathymetry and for land elevation data was generated by RTK - GPS survey for a distance of 1 km from shore and SRTM for the inland areas. The model results show that in addition to the Sumatra source which generated the IOT in 2004, earthquakes originating in Car Nicobar and North Andaman can inflict more damage. The North Andaman source can generate a massive tsunami and an earthquake of magnitude more than Mw 9 can not only affect Tamil Nadu but also entire south east coast of India. The runup water level is used to demarcate the tsunami threat zones in the villages using GIS.

  2. Post-eruptive flooding of Santorini caldera and implications for tsunami generation

    NASA Astrophysics Data System (ADS)

    Nomikou, P.; Druitt, T. H.; Hübscher, C.; Mather, T. A.; Paulatto, M.; Kalnins, L. M.; Kelfoun, K.; Papanikolaou, D.; Bejelou, K.; Lampridou, D.; Pyle, D. M.; Carey, S.; Watts, A. B.; Weiß, B.; Parks, M. M.

    2016-11-01

    Caldera-forming eruptions of island volcanoes generate tsunamis by the interaction of different eruptive phenomena with the sea. Such tsunamis are a major hazard, but forward models of their impacts are limited by poor understanding of source mechanisms. The caldera-forming eruption of Santorini in the Late Bronze Age is known to have been tsunamigenic, and caldera collapse has been proposed as a mechanism. Here, we present bathymetric and seismic evidence showing that the caldera was not open to the sea during the main phase of the eruption, but was flooded once the eruption had finished. Inflow of water and associated landsliding cut a deep, 2.0-2.5 km3, submarine channel, thus filling the caldera in less than a couple of days. If, as at most such volcanoes, caldera collapse occurred syn-eruptively, then it cannot have generated tsunamis. Entry of pyroclastic flows into the sea, combined with slumping of submarine pyroclastic accumulations, were the main mechanisms of tsunami production.

  3. Post-eruptive flooding of Santorini caldera and implications for tsunami generation

    PubMed Central

    Nomikou, P.; Druitt, T. H.; Hübscher, C.; Mather, T. A.; Paulatto, M.; Kalnins, L. M.; Kelfoun, K.; Papanikolaou, D.; Bejelou, K.; Lampridou, D.; Pyle, D. M.; Carey, S.; Watts, A. B.; Weiß, B.; Parks, M. M.

    2016-01-01

    Caldera-forming eruptions of island volcanoes generate tsunamis by the interaction of different eruptive phenomena with the sea. Such tsunamis are a major hazard, but forward models of their impacts are limited by poor understanding of source mechanisms. The caldera-forming eruption of Santorini in the Late Bronze Age is known to have been tsunamigenic, and caldera collapse has been proposed as a mechanism. Here, we present bathymetric and seismic evidence showing that the caldera was not open to the sea during the main phase of the eruption, but was flooded once the eruption had finished. Inflow of water and associated landsliding cut a deep, 2.0–2.5 km3, submarine channel, thus filling the caldera in less than a couple of days. If, as at most such volcanoes, caldera collapse occurred syn-eruptively, then it cannot have generated tsunamis. Entry of pyroclastic flows into the sea, combined with slumping of submarine pyroclastic accumulations, were the main mechanisms of tsunami production. PMID:27824353

  4. Post-eruptive flooding of Santorini caldera and implications for tsunami generation.

    PubMed

    Nomikou, P; Druitt, T H; Hübscher, C; Mather, T A; Paulatto, M; Kalnins, L M; Kelfoun, K; Papanikolaou, D; Bejelou, K; Lampridou, D; Pyle, D M; Carey, S; Watts, A B; Weiß, B; Parks, M M

    2016-11-08

    Caldera-forming eruptions of island volcanoes generate tsunamis by the interaction of different eruptive phenomena with the sea. Such tsunamis are a major hazard, but forward models of their impacts are limited by poor understanding of source mechanisms. The caldera-forming eruption of Santorini in the Late Bronze Age is known to have been tsunamigenic, and caldera collapse has been proposed as a mechanism. Here, we present bathymetric and seismic evidence showing that the caldera was not open to the sea during the main phase of the eruption, but was flooded once the eruption had finished. Inflow of water and associated landsliding cut a deep, 2.0-2.5 km 3 , submarine channel, thus filling the caldera in less than a couple of days. If, as at most such volcanoes, caldera collapse occurred syn-eruptively, then it cannot have generated tsunamis. Entry of pyroclastic flows into the sea, combined with slumping of submarine pyroclastic accumulations, were the main mechanisms of tsunami production.

  5. Numerical study of tsunami generated by multiple submarine slope failures in Resurrection Bay, Alaska, during the MW 9.2 1964 earthquake

    USGS Publications Warehouse

    Suleimani, E.; Hansen, R.; Haeussler, Peter J.

    2009-01-01

    We use a viscous slide model of Jiang and LeBlond (1994) coupled with nonlinear shallow water equations to study tsunami waves in Resurrection Bay, in south-central Alaska. The town of Seward, located at the head of Resurrection Bay, was hit hard by both tectonic and local landslide-generated tsunami waves during the MW 9.2 1964 earthquake with an epicenter located about 150 km northeast of Seward. Recent studies have estimated the total volume of underwater slide material that moved in Resurrection Bay during the earthquake to be about 211 million m3. Resurrection Bay is a glacial fjord with large tidal ranges and sediments accumulating on steep underwater slopes at a high rate. Also, it is located in a seismically active region above the Aleutian megathrust. All these factors make the town vulnerable to locally generated waves produced by underwater slope failures. Therefore it is crucial to assess the tsunami hazard related to local landslide-generated tsunamis in Resurrection Bay in order to conduct comprehensive tsunami inundation mapping at Seward. We use numerical modeling to recreate the landslides and tsunami waves of the 1964 earthquake to test the hypothesis that the local tsunami in Resurrection Bay has been produced by a number of different slope failures. We find that numerical results are in good agreement with the observational data, and the model could be employed to evaluate landslide tsunami hazard in Alaska fjords for the purposes of tsunami hazard mitigation. ?? Birkh??user Verlag, Basel 2009.

  6. Development of algorithms for tsunami detection by High Frequency Radar based on modeling tsunami case studies in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Grilli, S. T.; Guérin, C. A.; Grosdidier, S.

    2014-12-01

    Where coastal tsunami hazard is governed by near-field sources, Submarine Mass Failures (SMFs) or earthquakes, tsunami propagation times may be too small for a detection based on deep or shallow water buoys. To offer sufficient warning time, it has been proposed by others to implement early warning systems relying on High Frequency Radar (HFR) remote sensing, that has a dense spatial coverage far offshore. A new HFR, referred to as STRADIVARIUS, is being deployed by Diginext Inc. (in Fall 2014), to cover the "Golfe du Lion" (GDL) in the Western Mediterranean Sea. This radar uses a proprietary phase coding technology that allows detection up to 300 km, in a bistatic configuration (for which radar and antennas are separated by about 100 km). Although the primary purpose of the radar is vessel detection in relation to homeland security, the 4.5 MHz HFR will provide a strong backscattered signal for ocean surface waves at the so-called Bragg frequency (here, wavelength of 30 m). The current caused by an arriving tsunami will shift the Bragg frequency, by a value proportional to the current magnitude (projected on the local radar ray direction), which can be easily obtained from the Doppler spectrum of the HFR signal. Using state of the art tsunami generation and propagation models, we modeled tsunami case studies in the western Mediterranean basin (both seismic and SMFs) and simulated the HFR backscattered signal that would be detected for the entire GDL and beyond. Based on simulated HFR signal, we developed two types of tsunami detection algorithms: (i) one based on standard Doppler spectra, for which we found that to be detectable within the environmental and background current noises, the Doppler shift requires tsunami currents to be at least 10-15 cm/s, which typically only occurs on the continental shelf in fairly shallow water; (ii) to allow earlier detection, a second algorithm computes correlations of the HFR signals at two distant locations, shifted in time

  7. Development of algorithms for tsunami detection by High Frequency Radar based on modeling tsunami case studies in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Grilli, Stéphan; Guérin, Charles-Antoine; Grosdidier, Samuel

    2015-04-01

    Where coastal tsunami hazard is governed by near-field sources, Submarine Mass Failures (SMFs) or earthquakes, tsunami propagation times may be too small for a detection based on deep or shallow water buoys. To offer sufficient warning time, it has been proposed by others to implement early warning systems relying on High Frequency Surface Wave Radar (HFSWR) remote sensing, that has a dense spatial coverage far offshore. A new HFSWR, referred to as STRADIVARIUS, has been recently deployed by Diginext Inc. to cover the "Golfe du Lion" (GDL) in the Western Mediterranean Sea. This radar, which operates at 4.5 MHz, uses a proprietary phase coding technology that allows detection up to 300 km in a bistatic configuration (with a baseline of about 100 km). Although the primary purpose of the radar is vessel detection in relation to homeland security, it can also be used for ocean current monitoring. The current caused by an arriving tsunami will shift the Bragg frequency by a value proportional to a component of its velocity, which can be easily obtained from the Doppler spectrum of the HFSWR signal. Using state of the art tsunami generation and propagation models, we modeled tsunami case studies in the western Mediterranean basin (both seismic and SMFs) and simulated the HFSWR backscattered signal that would be detected for the entire GDL and beyond. Based on simulated HFSWR signal, we developed two types of tsunami detection algorithms: (i) one based on standard Doppler spectra, for which we found that to be detectable within the environmental and background current noises, the Doppler shift requires tsunami currents to be at least 10-15 cm/s, which typically only occurs on the continental shelf in fairly shallow water; (ii) to allow earlier detection, a second algorithm computes correlations of the HFSWR signals at two distant locations, shifted in time by the tsunami propagation time between these locations (easily computed based on bathymetry). We found that this

  8. Sedimentological effects of tsunamis, with particular reference to impact-generated and volcanogenic waves

    NASA Technical Reports Server (NTRS)

    Bourgeois, Joanne; Wiberg, Patricia L.

    1988-01-01

    Impulse-generated waves (tsunamis) may be produced, at varying scales and global recurrence intervals (RI), by several processes. Meteorite-water impacts will produce tsunamis, and asteroid-scale impacts with associated mega-tsunamis may occur. A bolide-water impact would undoubtedly produce a major tsunami, whose sedimentological effects should be recognizable. Even a bolide-land impact might trigger major submarine landslides and thus tsunamis. In all posulated scenarios for the K/T boundary event, then, tsunamis are expected, and where to look for them must be determined, and how to distinguish deposits from different tsunamis. Also, because tsunamis decrease in height as they move away from their source, the proximal effects will differ by perhaps orders of magnitude from distal effects. Data on the characteristics of tsunamis at their origin are scarce. Some observations exist for tsunamis generated by thermonuclear explosions and for seismogenic tsunamis, and experimental work was conducted on impact-generated tsunamis. All tsunamis of interest have wave-lengths of 0(100) km and thus behave as shallow-water waves in all ocean depths. Typical wave periods are 0(10 to 100) minutes. The effect of these tsunamis can be estimated in the marine and coastal realm by calculating boundary shear stresses (expressed as U*, the shear velocity). An event layer at the K/T boundary in Texas occurs in mid-shelf muds. Only a large, long-period wave with a wave height of 0(50) m, is deemed sufficient to have produced this layer. Such wave heights imply a nearby volcanic explosion on the scale of Krakatau or larger, or a nearby submarine landslide also of great size, or a bolide-water impact in the ocean.

  9. Rapid tsunami models and earthquake source parameters: Far-field and local applications

    USGS Publications Warehouse

    Geist, E.L.

    2005-01-01

    Rapid tsunami models have recently been developed to forecast far-field tsunami amplitudes from initial earthquake information (magnitude and hypocenter). Earthquake source parameters that directly affect tsunami generation as used in rapid tsunami models are examined, with particular attention to local versus far-field application of those models. First, validity of the assumption that the focal mechanism and type of faulting for tsunamigenic earthquakes is similar in a given region can be evaluated by measuring the seismic consistency of past events. Second, the assumption that slip occurs uniformly over an area of rupture will most often underestimate the amplitude and leading-wave steepness of the local tsunami. Third, sometimes large magnitude earthquakes will exhibit a high degree of spatial heterogeneity such that tsunami sources will be composed of distinct sub-events that can cause constructive and destructive interference in the wavefield away from the source. Using a stochastic source model, it is demonstrated that local tsunami amplitudes vary by as much as a factor of two or more, depending on the local bathymetry. If other earthquake source parameters such as focal depth or shear modulus are varied in addition to the slip distribution patterns, even greater uncertainty in local tsunami amplitude is expected for earthquakes of similar magnitude. Because of the short amount of time available to issue local warnings and because of the high degree of uncertainty associated with local, model-based forecasts as suggested by this study, direct wave height observations and a strong public education and preparedness program are critical for those regions near suspected tsunami sources.

  10. Post Fukushima tsunami simulations for Malaysian coasts

    SciTech Connect

    Koh, Hock Lye, E-mail: kohhl@ucsiuniversity.edu.my; Teh, Su Yean, E-mail: syteh@usm.my; Abas, Mohd Rosaidi Che

    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 formore » 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.« less

  11. Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes

    USGS Publications Warehouse

    Geist, E.L.; Bilek, S.L.; Arcas, D.; Titov, V.V.

    2006-01-01

    Source parameters affecting tsunami generation and propagation for the Mw > 9.0 December 26, 2004 and the Mw = 8.6 March 28, 2005 earthquakes are examined to explain the dramatic difference in tsunami observations. We evaluate both scalar measures (seismic moment, maximum slip, potential energy) and finite-source repre-sentations (distributed slip and far-field beaming from finite source dimensions) of tsunami generation potential. There exists significant variability in local tsunami runup with respect to the most readily available measure, seismic moment. The local tsunami intensity for the December 2004 earthquake is similar to other tsunamigenic earthquakes of comparable magnitude. In contrast, the March 2005 local tsunami was deficient relative to its earthquake magnitude. Tsunami potential energy calculations more accurately reflect the difference in tsunami severity, although these calculations are dependent on knowledge of the slip distribution and therefore difficult to implement in a real-time system. A significant factor affecting tsunami generation unaccounted for in these scalar measures is the location of regions of seafloor displacement relative to the overlying water depth. The deficiency of the March 2005 tsunami seems to be related to concentration of slip in the down-dip part of the rupture zone and the fact that a substantial portion of the vertical displacement field occurred in shallow water or on land. The comparison of the December 2004 and March 2005 Sumatra earthquakes presented in this study is analogous to previous studies comparing the 1952 and 2003 Tokachi-Oki earthquakes and tsunamis, in terms of the effect slip distribution has on local tsunamis. Results from these studies indicate the difficulty in rapidly assessing local tsunami runup from magnitude and epicentral location information alone.

  12. Coral reefs reduce tsunami impact in model simulations

    NASA Astrophysics Data System (ADS)

    Kunkel, Catherine M.; Hallberg, Robert W.; Oppenheimer, Michael

    2006-12-01

    Significant buffering of the impact of tsunamis by coral reefs is suggested by limited observations and some anecdotal reports, particularly following the 2004 Indian Ocean tsunami. Here we simulate tsunami run-up on idealized topographies in one and two dimensions using a nonlinear shallow water model and show that a sufficiently wide barrier reef within a meter or two of the surface reduces run-up on land on the order of 50%. We studied topographies representative of volcanic islands (islands with no continental shelf) but our conclusions may pertain to other topographies. Effectiveness depends on the amplitude and wavelength of the incident tsunami, as well as the geometry and health of the reef and the offshore distance of the reef. Reducing the threat to reefs from anthropogenic nutrients, sedimentation, fishing practices, channel-building, and global warming would help to protect some islands against tsunamis.

  13. Tsunami simulation using submarine displacement calculated from simulation of ground motion due to seismic source model

    NASA Astrophysics Data System (ADS)

    Akiyama, S.; Kawaji, K.; Fujihara, S.

    2013-12-01

    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.

  14. 3D numerical investigation on landslide generated tsunamis around a conical island

    NASA Astrophysics Data System (ADS)

    Montagna, Francesca; Bellotti, Giorgio

    2010-05-01

    This paper presents numerical computations of tsunamis generated by subaerial and submerged landslides falling along the flank of a conical island. The study is inspired by the tsunamis that on 30th December 2002 attacked the coast of the volcanic island of Stromboli (South Tyrrhenian sea, Italy). In particular this paper analyzes the important feature of the lateral spreading of landside generated tsunamis and the associated flooding hazard. The numerical model used in this study is the full three dimensional commercial code FLOW-3D. The model has already been successfully used (Choi et al., 2007; 2008; Chopakatla et al, 2008) to study the interaction of waves and structures. In the simulations carried out in this work a particular feature of the code has been employed: the GMO (General Moving Object) algorithm. It allows to reproduce the interaction between moving objects, as a landslide, and the water. FLOW-3D has been firstly validated using available 3D experiments reproducing tsunamis generated by landslides at the flank of a conical island. The experiments have been carried out in the LIC laboratory of the Polytechnic of Bari, Italy (Di Risio et al., 2009). Numerical and experimental time series of run-up and sea level recorded at gauges located at the flanks of the island and offshore have been successfully compared. This analysis shows that the model can accurately represent the generation, the propagation and the inundation of landslide generated tsunamis and suggests the use of the numerical model as a tool for preparing inundation maps. At the conference we will present the validation of the model and parametric analyses aimed to investigate how wave properties depend on the landslide kinematic and on further parameters such as the landslide volume and shape, as well as the radius of the island. The expected final results of the research are precomputed inundation maps that depend on the characteristics of the landslide and of the island. Finally we

  15. Modelling the tsunami threat to Sydney Harbour, Australia, with comparisons to historical events.

    NASA Astrophysics Data System (ADS)

    Wilson, O.; Power, H.

    2016-12-01

    Sydney Harbour is an iconic location with a dense population and low-lying development. On the east coast of Australia, facing the Pacific Ocean it is exposed to several tsunamigenic trenches. To date, this is the most detailed assessment of the potential for earthquake-generated tsunami impact on Sydney Harbour. The tsunami wave trains modelled include tsunami modelled from earthquakes of magnitude 7.5, 8.0, 8.5 and 9.0 MW from the Puysegur and New Hebrides trenches. Historical events from Chile in 1960 and Japan in 2011 are also modelled for comparison. Using the hydrodynamic model ANUGA, results show that the events modelled have the potential to cause high current speeds, hazardous waves and rapid changes in water level. These effects are most dramatic at pinch points such as Spit Bridge and Anzac Bridge, particularly with regard to current speeds. Large waves are shown to be a particular threat at the mouth of the harbour, where the bathymetry causes the tsunami wave train to shoal. Inundation is less of a hazard for the tsunami events modlled, although some inundation is evident at several low-lying embayments in the south of the harbour. These results will provide an evidence base for tsunami threat emergency management.

  16. Improved tsunami impact assessments: validation, comparison and the integration of hydrodynamic modeling

    NASA Astrophysics Data System (ADS)

    Tarbotton, C.; Walters, R. A.; Goff, J. R.; Dominey-Howes, D.; Turner, I. L.

    2012-12-01

    As communities become increasingly aware of the risks posed by tsunamis, it is important to develop methods for predicting the damage they can cause to the built environment. This will provide the information needed to make informed decisions regarding land-use, building codes, and evacuation. At present, a number of tsunami-building vulnerability assessment models are available, however, the relative infrequency and destructive nature of tsunamis has long made it difficult to obtain the data necessary to adequately validate and compare them. Further complicating matters is that the inundation of a tsunami in the built environment is very difficult model, as is the response of a building to the hydraulic forces that a tsunami generates. Variations in building design and condition will significantly affect a building's susceptibility to damage. Likewise, factors affecting the flow conditions at a building (i.e. surrounding structures and topography), will greatly affect its exposure. This presents significant challenges for practitioners, as they are often left in the dark on how to use hazard modeling and vulnerability assessment techniques together to conduct the community-scale impact studies required for tsunami planning. This paper presents the results of an in-depth case study of Yuriage, Miyagi Prefecture - a coastal city in Japan that was badly damaged by the 2011 Tohoku tsunami. The aim of the study was twofold: 1) To test and compare existing tsunami vulnerability assessment models and 2) To more effectively utilize hydrodynamic models in the context of tsunami impact studies. Following the 2011 Tohoku event, an unprecedented quantity of field data, imagery and video emerged. Yuriage in particular, features a comprehensive set of street level Google Street View imagery, available both before and after the event. This has enabled the collection of a large dataset describing the characteristics of the buildings existing before the event as well the

  17. Development of Physics and Control of Multiple Forcing Mechanisms for the Alaska Tsunami Forecast Model

    NASA Astrophysics Data System (ADS)

    Bahng, B.; Whitmore, P.; Macpherson, K. A.; Knight, W. R.

    2016-12-01

    The Alaska Tsunami Forecast Model (ATFM) is a numerical model used to forecast propagation and inundation of tsunamis generated by earthquakes or other mechanisms in either the Pacific Ocean, Atlantic Ocean or Gulf of Mexico. At the U.S. National Tsunami Warning Center (NTWC), the use of the model has been mainly for tsunami pre-computation due to earthquakes. That is, results for hundreds of hypothetical events are computed before alerts, and are accessed and calibrated with observations during tsunamis to immediately produce forecasts. The model has also been used for tsunami hindcasting due to submarine landslides and due to atmospheric pressure jumps, but in a very case-specific and somewhat limited manner. ATFM uses the non-linear, depth-averaged, shallow-water equations of motion with multiply nested grids in two-way communications between domains of each parent-child pair as waves approach coastal waters. The shallow-water wave physics is readily applicable to all of the above tsunamis as well as to tides. Recently, the model has been expanded to include multiple forcing mechanisms in a systematic fashion, and to enhance the model physics for non-earthquake events.ATFM is now able to handle multiple source mechanisms, either individually or jointly, which include earthquake, submarine landslide, meteo-tsunami and tidal forcing. As for earthquakes, the source can be a single unit source or multiple, interacting source blocks. Horizontal slip contribution can be added to the sea-floor displacement. The model now includes submarine landslide physics, modeling the source either as a rigid slump, or as a viscous fluid. Additional shallow-water physics have been implemented for the viscous submarine landslides. With rigid slumping, any trajectory can be followed. As for meteo-tsunami, the forcing mechanism is capable of following any trajectory shape. Wind stress physics has also been implemented for the meteo-tsunami case, if required. As an example of multiple

  18. Tsunamis generated by eruptions from mount st. Augustine volcano, alaska.

    PubMed

    Kienle, J; Kowalik, Z; Murty, T S

    1987-06-12

    During an eruption of the Alaskan volcano Mount St. Augustine in the spring of 1986, there was concern about the possibility that a tsunami might be generated by the collapse of a portion of the volcano into the shallow water of Cook Inlet. A similar edifice collapse of the volcano and ensuing sea wave occurred during an eruption in 1883. Other sea waves resulting in great loss of life and property have been generated by the eruption of coastal volcanos around the world. Although Mount St. Augustine remained intact during this eruptive cycle, a possible recurrence of the 1883 events spurred a numerical simulation of the 1883 sea wave. This simulation, which yielded a forecast of potential wave heights and travel times, was based on a method that could be applied generally to other coastal volcanos.

  19. Tsunami Generation and Propagation by 3D deformable Landslides and Application to Scenarios

    NASA Astrophysics Data System (ADS)

    McFall, Brian C.; Fritz, Hermann M.

    2014-05-01

    Tsunamis generated by landslides and volcano flank collapse account for some of the most catastrophic natural disasters recorded and can be particularly devastative in the near field region due to locally high wave amplitudes and runup. The events of 1958 Lituya Bay, 1963 Vajont reservoir, 1980 Spirit Lake, 2002 Stromboli and 2010 Haiti demonstrate the danger of tsunamis generated by landslides or volcano flank collapses. Unfortunately critical field data from these events is lacking. Source and runup scenarios based on real world events are physically modeled using generalized Froude similarity in the three dimensional NEES tsunami wave basin at Oregon State University. A novel pneumatic landslide tsunami generator (LTG) was deployed to simulate landslides with varying geometry and kinematics. The bathymetric and topographic scenarios tested with the LTG are the basin-wide propagation and runup, fjord, curved headland fjord and a conical island setting representing a landslide off an island or a volcano flank collapse. The LTG consists of a sliding box filled with 1,350 kg of landslide material which is accelerated by means of four pneumatic pistons down a 2H:1V slope. The landslide is launched from the sliding box and continues to accelerate by gravitational forces up to velocities of 5 m/s. The landslide Froude number at impact with the water is in the range 1

  20. Confirmation and calibration of computer modeling of tsunamis produced by Augustine volcano, Alaska

    USGS Publications Warehouse

    Beget, James E.; Kowalik, Zygmunt

    2006-01-01

    Numerical modeling has been used to calculate the characteristics of a tsunami generated by a landslide into Cook Inlet from Augustine Volcano. The modeling predicts travel times of ca. 50-75 minutes to the nearest populated areas, and indicates that significant wave amplification occurs near Mt. Iliamna on the western side of Cook Inlet, and near the Nanwelak and the Homer-Anchor Point areas on the east side of Cook Inlet. Augustine volcano last produced a tsunami during an eruption in 1883, and field evidence of the extent and height of the 1883 tsunamis can be used to test and constrain the results of the computer modeling. Tsunami deposits on Augustine Island indicate waves near the landslide source were more than 19 m high, while 1883 tsunami deposits in distal sites record waves 6-8 m high. Paleotsunami deposits were found at sites along the coast near Mt. Iliamna, Nanwelak, and Homer, consistent with numerical modeling indicating significant tsunami wave amplification occurs in these areas. 

  1. Modeling the mitigation effect of coastal forests on tsunami

    NASA Astrophysics Data System (ADS)

    Kh'ng, Xin Yi; Teh, Su Yean; Koh, Hock Lye

    2017-08-01

    As we have learned from the 26 Dec 2004 mega Andaman tsunami that killed 250, 000 lives worldwide, tsunami is a devastating natural disaster that can cause severe impacts including immense loss of human lives and extensive destruction of properties. The wave energy can be dissipated by the presence of coastal mangrove forests, which provide some degree of protection against tsunami waves. On the other hand, costly artificial structures such as reinforced walls can substantially diminish the aesthetic value and may cause environmental problems. To quantify the effectiveness of coastal forests in mitigating tsunami waves, an in-house 2-D model TUNA-RP is developed and used to quantify the reduction in wave heights and velocities due to the presence of coastal forests. The degree of reduction varies significantly depending on forest flow-resistant properties such as vegetation characteristics, forest density and forest width. The ability of coastal forest in reducing tsunami wave heights along the west coast of Penang Island is quantified by means of model simulations. Comparison between measured tsunami wave heights for the 2004 Andaman tsunami and 2-D TUNA-RP model simulated values demonstrated good agreement.

  2. Inter-model analysis of tsunami-induced coastal currents

    NASA Astrophysics Data System (ADS)

    Lynett, Patrick J.; Gately, Kara; Wilson, Rick; Montoya, Luis; Arcas, Diego; Aytore, Betul; Bai, Yefei; Bricker, Jeremy D.; Castro, Manuel J.; Cheung, Kwok Fai; David, C. Gabriel; Dogan, Gozde Guney; Escalante, Cipriano; González-Vida, José Manuel; Grilli, Stephan T.; Heitmann, Troy W.; Horrillo, Juan; Kânoğlu, Utku; Kian, Rozita; Kirby, James T.; Li, Wenwen; Macías, Jorge; Nicolsky, Dmitry J.; Ortega, Sergio; Pampell-Manis, Alyssa; Park, Yong Sung; Roeber, Volker; Sharghivand, Naeimeh; Shelby, Michael; Shi, Fengyan; Tehranirad, Babak; Tolkova, Elena; Thio, Hong Kie; Velioğlu, Deniz; Yalçıner, Ahmet Cevdet; Yamazaki, Yoshiki; Zaytsev, Andrey; Zhang, Y. J.

    2017-06-01

    To help produce accurate and consistent maritime hazard products, the National Tsunami Hazard Mitigation Program organized a benchmarking workshop to evaluate the numerical modeling of tsunami currents. Thirteen teams of international researchers, using a set of tsunami models currently utilized for hazard mitigation studies, presented results for a series of benchmarking problems; these results are summarized in this paper. Comparisons focus on physical situations where the currents are shear and separation driven, and are thus de-coupled from the incident tsunami waveform. In general, we find that models of increasing physical complexity provide better accuracy, and that low-order three-dimensional models are superior to high-order two-dimensional models. Inside separation zones and in areas strongly affected by eddies, the magnitude of both model-data errors and inter-model differences can be the same as the magnitude of the mean flow. Thus, we make arguments for the need of an ensemble modeling approach for areas affected by large-scale turbulent eddies, where deterministic simulation may be misleading. As a result of the analyses presented herein, we expect that tsunami modelers now have a better awareness of their ability to accurately capture the physics of tsunami currents, and therefore a better understanding of how to use these simulation tools for hazard assessment and mitigation efforts.

  3. Examination of the largest-possible tsunamis (Level 2) generated along the Nankai and Suruga troughs during the past 4000 years based on studies of tsunami deposits from the 2011 Tohoku-oki tsunami

    NASA Astrophysics Data System (ADS)

    Kitamura, Akihisa

    2016-12-01

    Japanese historical documents reveal that Mw 8 class earthquakes have occurred every 100-150 years along the Suruga and Nankai troughs since the 684 Hakuho earthquake. These earthquakes have commonly caused large tsunamis with wave heights of up to 10 m in the Japanese coastal area along the Suruga and Nankai troughs. From the perspective of tsunami disaster management, these tsunamis are designated as Level 1 tsunamis and are the basis for the design of coastal protection facilities. A Mw 9.0 earthquake (the 2011 Tohoku-oki earthquake) and a mega-tsunami with wave heights of 10-40 m struck the Pacific coast of the northeastern Japanese mainland on 11 March 2011, and far exceeded pre-disaster predictions of wave height. Based on the lessons learned from the 2011 Tohoku-oki earthquake, the Japanese Government predicted the tsunami heights of the largest-possible tsunami (termed a Level 2 tsunami) that could be generated in the Suruga and Nankai troughs. The difference in wave heights between Level 1 and Level 2 tsunamis exceeds 20 m in some areas, including the southern Izu Peninsula. This study reviews the distribution of prehistorical tsunami deposits and tsunami boulders during the past 4000 years, based on previous studies in the coastal area of Shizuoka Prefecture, Japan. The results show that a tsunami deposit dated at 3400-3300 cal BP can be traced between the Shimizu, Shizuoka and Rokken-gawa lowlands, whereas no geologic evidence related to the corresponding tsunami (the Rokken-gawa-Oya tsunami) was found on the southern Izu Peninsula. Thus, the Rokken-gawa-Oya tsunami is not classified as a Level 2 tsunami.

  4. Modeling of the 2011 Tohoku-oki Tsunami and its Impacts on Hawaii

    NASA Astrophysics Data System (ADS)

    Cheung, K.; Yamazaki, Y.; Roeber, V.; Lay, T.

    2011-12-01

    The 2011 Tohoku-oki great earthquake (Mw 9.0) generated a destructive tsunami along the entire Pacific coast of northeastern Japan. The tsunami, which registered 6.7 m amplitude at a coastal GPS gauge and 1.75 m at an open-ocean DART buoy, triggered warnings across the Pacific. The waves reached Hawaii 7 hours after the earthquake and caused localized damage and persistent coastal oscillations along the island chain. Several tide gauges and a DART buoy west of Hawaii Island recorded clear signals of the tsunami. The Tsunami Observer Program of Hawaii State Civil Defense immediately conducted field surveys to gather runup and inundation data on Kauai, Oahu, Maui, and Hawaii Island. The extensive global seismic networks and geodetic instruments allows evaluation and validation of finite fault solutions for the tsunami modeling. We reconstruct the 2011 Tohoku-oki tsunami using the long-wave model NEOWAVE (Non-hydrostatic Evolution of Ocean WAVEs) and a finite fault solution based on inversion of teleseismic P waves. The depth-integrated model describes dispersive waves through the non-hydrostatic pressure and vertical velocity, which also account for tsunami generation from time histories of seafloor deformation. The semi-implicit, staggered finite difference model captures flow discontinuities associated with bores or hydraulic jumps through the momentum-conserved advection scheme. Four levels of two-way nested grids in spherical coordinates allow description of tsunami evolution processes of different time and spatial scales for investigation of the impacts around the Hawaiian Islands. The model results are validated with DART data across the Pacific as well as tide gauge and runup measurements in Hawaii. Spectral analysis of the computed surface elevation reveals a series of resonance modes over the insular shelf and slope complex along the archipelago. Resonance oscillations provide an explanation for the localized impacts and the persistent wave activities in the

  5. Tsunami Simulations in the Western Makran Using Hypothetical Heterogeneous Source Models from World's Great Earthquakes

    NASA Astrophysics Data System (ADS)

    Rashidi, Amin; Shomali, Zaher Hossein; Keshavarz Farajkhah, Nasser

    2018-03-01

    The western segment of Makran subduction zone is characterized with almost no major seismicity and no large earthquake for several centuries. A possible episode for this behavior is that this segment is currently locked accumulating energy to generate possible great future earthquakes. Taking into account this assumption, a hypothetical rupture area is considered in the western Makran to set different tsunamigenic scenarios. Slip distribution models of four recent tsunamigenic earthquakes, i.e. 2015 Chile M w 8.3, 2011 Tohoku-Oki M w 9.0 (using two different scenarios) and 2006 Kuril Islands M w 8.3, are scaled into the rupture area in the western Makran zone. The numerical modeling is performed to evaluate near-field and far-field tsunami hazards. Heterogeneity in slip distribution results in higher tsunami amplitudes. However, its effect reduces from local tsunamis to regional and distant tsunamis. Among all considered scenarios for the western Makran, only a similar tsunamigenic earthquake to the 2011 Tohoku-Oki event can re-produce a significant far-field tsunami and is considered as the worst case scenario. The potential of a tsunamigenic source is dominated by the degree of slip heterogeneity and the location of greatest slip on the rupture area. For the scenarios with similar slip patterns, the mean slip controls their relative power. Our conclusions also indicate that along the entire Makran coasts, the southeastern coast of Iran is the most vulnerable area subjected to tsunami hazard.

  6. Tsunami Simulations in the Western Makran Using Hypothetical Heterogeneous Source Models from World's Great Earthquakes

    NASA Astrophysics Data System (ADS)

    Rashidi, Amin; Shomali, Zaher Hossein; Keshavarz Farajkhah, Nasser

    2018-04-01

    The western segment of Makran subduction zone is characterized with almost no major seismicity and no large earthquake for several centuries. A possible episode for this behavior is that this segment is currently locked accumulating energy to generate possible great future earthquakes. Taking into account this assumption, a hypothetical rupture area is considered in the western Makran to set different tsunamigenic scenarios. Slip distribution models of four recent tsunamigenic earthquakes, i.e. 2015 Chile M w 8.3, 2011 Tohoku-Oki M w 9.0 (using two different scenarios) and 2006 Kuril Islands M w 8.3, are scaled into the rupture area in the western Makran zone. The numerical modeling is performed to evaluate near-field and far-field tsunami hazards. Heterogeneity in slip distribution results in higher tsunami amplitudes. However, its effect reduces from local tsunamis to regional and distant tsunamis. Among all considered scenarios for the western Makran, only a similar tsunamigenic earthquake to the 2011 Tohoku-Oki event can re-produce a significant far-field tsunami and is considered as the worst case scenario. The potential of a tsunamigenic source is dominated by the degree of slip heterogeneity and the location of greatest slip on the rupture area. For the scenarios with similar slip patterns, the mean slip controls their relative power. Our conclusions also indicate that along the entire Makran coasts, the southeastern coast of Iran is the most vulnerable area subjected to tsunami hazard.

  7. Generation of the September 29, 2009 Samoa Tsunami: Examination of a Possible Non-Double Couple Component (Invited)

    NASA Astrophysics Data System (ADS)

    Geist, E. L.; Kirby, S. H.; Ross, S.; Dartnell, P.

    2009-12-01

    A non-double couple component associated with the Mw=8.0 September 29, 2009 Samoa earthquake is investigated to explain direct tsunami arrivals at deep-ocean pressure sensors (i.e., DART stations). In particular, we seek a tsunami generation model that correctly predicts the polarity of first motions: negative at the Apia station (#51425) NW of the epicenter and positive at the Tonga (#51426) and Aukland (#54401) stations south of the epicenter. Slip on a single, finite fault corresponding to either nodal plane of the best-fitting double couple fails to predict the positive first-motion polarity observed at the southerly (Tonga and Aukland) DART stations. The Samoa earthquake has a significant non-double component as measured by the compensated linear vector dipole (CLVD) ratio that ranges from |ɛ|=0.15 (USGS CMT) to |ɛ| =0.37 (Global CMT). To test what effect the non-double component has on tsunami generation, the static elastic displacement field at the sea floor is computed from the full moment tensor. This displacement field represents the initial conditions for tsunami propagation computed using a finite-difference approximation to the linear shallow-water wave equations. The tsunami waveforms calculated from the full moment tensor are consistent with the observed polarities at all of the DART stations. The static displacement field is then decomposed into double-couple and non-double couple components to determine the relative contribution of each to the tsunami wavefield. Although a point-source approximation to the tsunami source is typically inadequate at near-field and regional distances, finite-fault inversions of the 2009 Samoa earthquake indicate that peak slip is spatially concentrated near the hypocenter, suggesting that the point-source representation may be acceptable in this case. Generation of the 2009 Samoa tsunami may involve earthquake rupture on multiple faults and/or along curved faults, both of which are observed from multibeam bathymetry

  8. Analysis of Tsunami Evacuation Issues Using Agent Based Modeling. A Case Study of the 2011 Tohoku Tsunami in Yuriage, Natori.

    NASA Astrophysics Data System (ADS)

    Mas, E.; Takagi, H.; Adriano, B.; Hayashi, S.; Koshimura, S.

    2014-12-01

    The 2011 Great East Japan earthquake and tsunami reminded that nature can exceed structural countermeasures like seawalls, breakwaters or tsunami gates. In such situations it is a challenging task for people to find nearby haven. This event, as many others before, confirmed the importance of early evacuation, tsunami awareness and the need for developing much more resilient communities with effective evacuation plans. To support reconstruction activities and efforts on developing resilient communities in areas at risk, tsunami evacuation simulation can be applied to tsunami mitigation and evacuation planning. In this study, using the compiled information related to the evacuation behavior at Yuriage in Natori during the 2011 tsunami, we simulated the evacuation process and explored the reasons for the large number of fatalities in the area. It was found that residents did evacuate to nearby shelter areas, however after the tsunami warning was increased some evacuees decided to conduct a second step evacuation to a far inland shelter. Simulation results show the consequences of such decision and the outcomes when a second evacuation would not have been performed. The actual reported number of fatalities in the event and the results from simulation are compared to verify the model. The case study shows the contribution of tsunami evacuation models as tools to be applied for the analysis of evacuees' decisions and the related outcomes. In addition, future evacuation plans and activities for reconstruction process and urban planning can be supported by the results provided from this kind of tsunami evacuation models.

  9. Tsunami-induced morphological change of a coastal lake: comparing hydraulic experiment with numerical modeling

    NASA Astrophysics Data System (ADS)

    Sugawara, D.; Imai, K.; Mitobe, Y.; Takahashi, T.

    2016-12-01

    Coastal lakes are one of the promising environments to identify deposits of past tsunamis, and such deposits have been an important key to know the recurrence of tsunami events. In contrast to tsunami deposits on the coastal plains, however, relationship between deposit geometry and tsunami hydrodynamic character in the coastal lakes has poorly been understood. Flume experiment and numerical modeling will be important measures to clarify such relationship. In this study, data from a series of flume experiment were compared with simulations by an existing tsunami sediment transport model to examine applicability of the numerical model for tsunami-induced morphological change in a coastal lake. A coastal lake with a non-erodible beach ridge was modeled as the target geomorphology. The ridge separates the lake from the offshore part of the flume, and the lake bottom was filled by sand. Tsunami bore was generated by a dam-break flow, which is capable of generating a maximum near-bed flow speed of 2.5 m/s. Test runs with varying magnitude of the bore demonstrated that the duration of tsunami overflow controls the scouring depth of the lake bottom behind the ridge. The maximum scouring depth reached up to 7 cm, and sand deposition occurred mainly in the seaward-half of the lake. A conventional depth-averaged tsunami hydrodynamic model coupled with the sediment transport model was used to compare the simulation and experimental results. In the Simulation, scouring depth behind the ridge reached up to 6 cm. In addition, the width of the scouring was consistent between the simulation and experiment. However, sand deposition occurred mainly in a zone much far from the ridge, showing a considerable deviation from the experimental results. This may be associated with the lack of model capability to resolve some important physics, such as vortex generation behind the ridge and shoreward migration of hydraulic jump. In this presentation, the results from the flume experiment and

  10. A new physics-based modeling approach for tsunami-ionosphere coupling

    NASA Astrophysics Data System (ADS)

    Meng, X.; Komjathy, A.; Verkhoglyadova, O. P.; Yang, Y.-M.; Deng, Y.; Mannucci, A. J.

    2015-06-01

    Tsunamis can generate gravity waves propagating upward through the atmosphere, inducing total electron content (TEC) disturbances in the ionosphere. To capture this process, we have implemented tsunami-generated gravity waves into the Global Ionosphere-Thermosphere Model (GITM) to construct a three-dimensional physics-based model WP (Wave Perturbation)-GITM. WP-GITM takes tsunami wave properties, including the wave height, wave period, wavelength, and propagation direction, as inputs and time-dependently characterizes the responses of the upper atmosphere between 100 km and 600 km altitudes. We apply WP-GITM to simulate the ionosphere above the West Coast of the United States around the time when the tsunami associated with the March 2011 Tohuku-Oki earthquke arrived. The simulated TEC perturbations agree with Global Positioning System observations reasonably well. For the first time, a fully self-consistent and physics-based model has reproduced the GPS-observed traveling ionospheric signatures of an actual tsunami event.

  11. Development of Tsunami Numerical Model Considering the Disaster Debris such as Cars, Ships and Collapsed Buildings

    NASA Astrophysics Data System (ADS)

    Kozono, Y.; Takahashi, T.; Sakuraba, M.; Nojima, K.

    2016-12-01

    A lot of debris by tsunami, such as cars, ships and collapsed buildings were generated in the 2011 Tohoku tsunami. It is useful for rescue and recovery after tsunami disaster to predict the amount and final position of disaster debris. The transport form of disaster debris varies as drifting, rolling and sliding. These transport forms need to be considered comprehensively in tsunami simulation. In this study, we focused on the following three points. Firstly, the numerical model considering various transport forms of disaster debris was developed. The proposed numerical model was compared with the hydraulic experiment by Okubo et al. (2004) in order to verify transport on the bottom surface such as rolling and sliding. Secondly, a numerical experiment considering transporting on the bottom surface and drifting was studied. Finally, the numerical model was applied for Kesennuma city where serious damage occurred by the 2011 Tohoku tsunami. In this model, the influence of disaster debris was considered as tsunami flow energy loss. The hydraulic experiments conducted in a water tank which was 10 m long by 30 cm wide. The gate confined water in a storage tank, and acted as a wave generator. A slope was set at downstream section. The initial position of a block (width: 3.2 cm, density: 1.55 g/cm3) assuming the disaster debris was placed in front of the slope. The proposed numerical model simulated well the maximum transport distance and the final stop position of the block. In the second numerical experiment, the conditions were the same as the hydraulic experiment, except for the density of the block. The density was set to various values (from 0.30 to 4.20 g/cm3). This model was able to estimate various transport forms including drifting and sliding. In the numerical simulation of the 2011 Tohoku tsunami, the condition of buildings was modeled as follows: (i)the resistance on the bottom using Manning roughness coefficient (conventional method), and (ii)structure of

  12. Tsunami Modeling of Hikurangi Trench M9 Events: Case Study for Napier, New Zealand

    NASA Astrophysics Data System (ADS)

    Williams, C. R.; Nyst, M.; Farahani, R.; Bryngelson, J.; Lee, R.; Molas, G.

    2015-12-01

    RMS has developed a tsunami model for New Zealand for the insurance industry to price and to manage their tsunami risks. A key tsunamigenic source for New Zealand is the Hikurangi Trench that lies offshore on the eastside of the North Island. The trench is the result of the subduction of the Pacific Plate beneath the North Island at a rate of 40-45 mm/yr. Though there have been no M9 historical events on the Hikurangi Trench, events in this magnitude range are considered in the latest version of the National Seismic Hazard Maps for New Zealand (Stirling et al., 2012). The RMS modeling approaches the tsunami lifecycle in three stages: event generation, ocean wave propagation, and coastal inundation. The tsunami event generation is modeled based on seafloor deformation resulting from an event rupture model. The ocean wave propagation and coastal inundation are modeled using a RMS-developed numerical solver, implemented on graphic processing units using a finite-volume approach to approximate two-dimensional, shallow-water wave equations over the ocean and complex topography. As the tsunami waves enter shallow water and approach the coast, the RMS model calculates the propagation of the waves along the wet-dry interface considering variable land friction. The initiation and characteristics of the tsunami are based on the event rupture model. As there have been no historical M9 events on the Hikurangi Trench, this rupture characterization posed unique challenges. This study examined the impacts of a suite of event rupture models to understand the key drivers in the variations in the tsunami inundation footprints. The goal was to develop a suite of tsunamigenic event characterizations that represent a range of potential tsunami outcomes for M9 events on the Hikurangi Trench. The focus of this case study is the Napier region as it represents an important exposure concentration in the region and has experience tsunami inundations in the past including during the 1931 Ms7

  13. Defining Tsunami Magnitude as Measure of Potential Impact

    NASA Astrophysics Data System (ADS)

    Titov, V. V.; Tang, L.

    2016-12-01

    The goal of tsunami forecast, as a system for predicting potential impact of a tsunami at coastlines, requires quick estimate of a tsunami magnitude. This goal has been recognized since the beginning of tsunami research. The work of Kajiura, Soloviev, Abe, Murty, and many others discussed several scales for tsunami magnitude based on estimates of tsunami energy. However, difficulties of estimating tsunami energy based on available tsunami measurements at coastal sea-level stations has carried significant uncertainties and has been virtually impossible in real time, before tsunami impacts coastlines. The slow process of tsunami magnitude estimates, including collection of vast amount of available coastal sea-level data from affected coastlines, made it impractical to use any tsunami magnitude scales in tsunami warning operations. Uncertainties of estimates made tsunami magnitudes difficult to use as universal scale for tsunami analysis. Historically, the earthquake magnitude has been used as a proxy of tsunami impact estimates, since real-time seismic data is available of real-time processing and ample amount of seismic data is available for an elaborate post event analysis. This measure of tsunami impact carries significant uncertainties in quantitative tsunami impact estimates, since the relation between the earthquake and generated tsunami energy varies from case to case. In this work, we argue that current tsunami measurement capabilities and real-time modeling tools allow for establishing robust tsunami magnitude that will be useful for tsunami warning as a quick estimate for tsunami impact and for post-event analysis as a universal scale for tsunamis inter-comparison. We present a method for estimating the tsunami magnitude based on tsunami energy and present application of the magnitude analysis for several historical events for inter-comparison with existing methods.

  14. Optimizing Tsunami Forecast Model Accuracy

    NASA Astrophysics Data System (ADS)

    Whitmore, P.; Nyland, D. L.; Huang, P. Y.

    2015-12-01

    Recent tsunamis provide a means to determine the accuracy that can be expected of real-time tsunami forecast models. Forecast accuracy using two different tsunami forecast models are compared for seven events since 2006 based on both real-time application and optimized, after-the-fact "forecasts". Lessons learned by comparing the forecast accuracy determined during an event to modified applications of the models after-the-fact provide improved methods for real-time forecasting for future events. Variables such as source definition, data assimilation, and model scaling factors are examined to optimize forecast accuracy. Forecast accuracy is also compared for direct forward modeling based on earthquake source parameters versus accuracy obtained by assimilating sea level data into the forecast model. Results show that including assimilated sea level data into the models increases accuracy by approximately 15% for the events examined.

  15. Nearshore Tsunami Inundation Model Validation: Toward Sediment Transport Applications

    USGS Publications Warehouse

    Apotsos, Alex; Buckley, Mark; Gelfenbaum, Guy; Jaffe, Bruce; Vatvani, Deepak

    2011-01-01

    Model predictions from a numerical model, Delft3D, based on the nonlinear shallow water equations are compared with analytical results and laboratory observations from seven tsunami-like benchmark experiments, and with field observations from the 26 December 2004 Indian Ocean tsunami. The model accurately predicts the magnitude and timing of the measured water levels and flow velocities, as well as the magnitude of the maximum inundation distance and run-up, for both breaking and non-breaking waves. The shock-capturing numerical scheme employed describes well the total decrease in wave height due to breaking, but does not reproduce the observed shoaling near the break point. The maximum water levels observed onshore near Kuala Meurisi, Sumatra, following the 26 December 2004 tsunami are well predicted given the uncertainty in the model setup. The good agreement between the model predictions and the analytical results and observations demonstrates that the numerical solution and wetting and drying methods employed are appropriate for modeling tsunami inundation for breaking and non-breaking long waves. Extension of the model to include sediment transport may be appropriate for long, non-breaking tsunami waves. Using available sediment transport formulations, the sediment deposit thickness at Kuala Meurisi is predicted generally within a factor of 2.

  16. The El Salvador and Philippines Tsunamis of August 2012: Insights from Sea Level Data Analysis and Numerical Modeling

    NASA Astrophysics Data System (ADS)

    Heidarzadeh, Mohammad; Satake, Kenji

    2014-12-01

    We studied two tsunamis from 2012, one generated by the El Salvador earthquake of 27 August ( Mw 7.3) and the other generated by the Philippines earthquake of 31 August ( Mw 7.6), using sea level data analysis and numerical modeling. For the El Salvador tsunami, the largest wave height was observed in Baltra, Galapagos Islands (71.1 cm) located about 1,400 km away from the source. The tsunami governing periods were around 9 and 19 min. Numerical modeling indicated that most of the tsunami energy was directed towards the Galapagos Islands, explaining the relatively large wave height there. For the Philippines tsunami, the maximum wave height of 30.5 cm was observed at Kushimoto in Japan located about 2,700 km away from the source. The tsunami governing periods were around 8, 12 and 29 min. Numerical modeling showed that a significant part of the far-field tsunami energy was directed towards the southern coast of Japan. Fourier and wavelet analyses as well as numerical modeling suggested that the dominant period of the first wave at stations normal to the fault strike is related to the fault width, while the period of the first wave at stations in the direction of fault strike is representative of the fault length.

  17. Ionospheric Method of Detecting Tsunami-Generating Earthquakes.

    ERIC Educational Resources Information Center

    Najita, Kazutoshi; Yuen, Paul C.

    1978-01-01

    Reviews the earthquake phenomenon and its possible relation to ionospheric disturbances. Discusses the basic physical principles involved and the methods upon which instrumentation is being developed for possible use in a tsunami disaster warning system. (GA)

  18. The exposure of Sydney (Australia) to earthquake-generated tsunamis, storms and sea level rise: a probabilistic multi-hazard approach

    PubMed Central

    Dall'Osso, F.; Dominey-Howes, D.; Moore, C.; Summerhayes, S.; Withycombe, G.

    2014-01-01

    Approximately 85% of Australia's population live along the coastal fringe, an area with high exposure to extreme inundations such as tsunamis. However, to date, no Probabilistic Tsunami Hazard Assessments (PTHA) that include inundation have been published for Australia. This limits the development of appropriate risk reduction measures by decision and policy makers. We describe our PTHA undertaken for the Sydney metropolitan area. Using the NOAA NCTR model MOST (Method for Splitting Tsunamis), we simulate 36 earthquake-generated tsunamis with annual probabilities of 1:100, 1:1,000 and 1:10,000, occurring under present and future predicted sea level conditions. For each tsunami scenario we generate a high-resolution inundation map of the maximum water level and flow velocity, and we calculate the exposure of buildings and critical infrastructure. Results indicate that exposure to earthquake-generated tsunamis is relatively low for present events, but increases significantly with higher sea level conditions. The probabilistic approach allowed us to undertake a comparison with an existing storm surge hazard assessment. Interestingly, the exposure to all the simulated tsunamis is significantly lower than that for the 1:100 storm surge scenarios, under the same initial sea level conditions. The results have significant implications for multi-risk and emergency management in Sydney. PMID:25492514

  19. The exposure of Sydney (Australia) to earthquake-generated tsunamis, storms and sea level rise: a probabilistic multi-hazard approach.

    PubMed

    Dall'Osso, F; Dominey-Howes, D; Moore, C; Summerhayes, S; Withycombe, G

    2014-12-10

    Approximately 85% of Australia's population live along the coastal fringe, an area with high exposure to extreme inundations such as tsunamis. However, to date, no Probabilistic Tsunami Hazard Assessments (PTHA) that include inundation have been published for Australia. This limits the development of appropriate risk reduction measures by decision and policy makers. We describe our PTHA undertaken for the Sydney metropolitan area. Using the NOAA NCTR model MOST (Method for Splitting Tsunamis), we simulate 36 earthquake-generated tsunamis with annual probabilities of 1:100, 1:1,000 and 1:10,000, occurring under present and future predicted sea level conditions. For each tsunami scenario we generate a high-resolution inundation map of the maximum water level and flow velocity, and we calculate the exposure of buildings and critical infrastructure. Results indicate that exposure to earthquake-generated tsunamis is relatively low for present events, but increases significantly with higher sea level conditions. The probabilistic approach allowed us to undertake a comparison with an existing storm surge hazard assessment. Interestingly, the exposure to all the simulated tsunamis is significantly lower than that for the 1:100 storm surge scenarios, under the same initial sea level conditions. The results have significant implications for multi-risk and emergency management in Sydney.

  20. Tsunami Modeling to Validate Slip Models of the 2007 M w 8.0 Pisco Earthquake, Central Peru

    NASA Astrophysics Data System (ADS)

    Ioualalen, M.; Perfettini, H.; Condo, S. Yauri; Jimenez, C.; Tavera, H.

    2013-03-01

    Following the 2007, August 15th, M w 8.0, Pisco earthquake in central Peru, Sladen et al. (J Geophys Res 115: B02405, 2010) have derived several slip models of this event. They inverted teleseismic data together with geodetic (InSAR) measurements to look for the co-seismic slip distribution on the fault plane, considering those data sets separately or jointly. But how close to the real slip distribution are those inverted slip models? To answer this crucial question, the authors generated some tsunami records based on their slip models and compared them to DART buoys, tsunami records, and available runup data. Such an approach requires a robust and accurate tsunami model (non-linear, dispersive, accurate bathymetry and topography, etc.) otherwise the differences between the data and the model may be attributed to the slip models themselves, though they arise from an incomplete tsunami simulation. The accuracy of a numerical tsunami simulation strongly depends, among others, on two important constraints: (i) A fine computational grid (and thus the bathymetry and topography data sets used) which is not always available, unfortunately, and (ii) a realistic tsunami propagation model including dispersion. Here, we extend Sladen's work using newly available data, namely a tide gauge record at Callao (Lima harbor) and the Chilean DART buoy record, while considering a complete set of runup data along with a more realistic tsunami numerical that accounts for dispersion, and also considering a fine-resolution computational grid, which is essential. Through these accurate numerical simulations we infer that the InSAR-based model is in better agreement with the tsunami data, studying the case of the Pisco earthquake indicating that geodetic data seems essential to recover the final co-seismic slip distribution on the rupture plane. Slip models based on teleseismic data are unable to describe the observed tsunami, suggesting that a significant amount of co-seismic slip may have

  1. Numerical simulation of the 2002 Northern Rhodes Slide (Greece) and evaluation of the generated tsunami

    NASA Astrophysics Data System (ADS)

    Zaniboni, Filippo; Armigliato, Alberto; Pagnoni, Gianluca; Tinti, Stefano

    2013-04-01

    Small landslides are very common along the submarine margins, due to steep slopes and continuous material deposition that increment mass instability and supply collapse occurrences, even without earthquake triggering. This kind of events can have relevant consequences when occurring close to the coast, because they are characterized by sudden change of velocity and relevant speed achievement, reflecting into high tsunamigenic potential. This is the case for example of the slide of Rhodes Island (Greece), named Northern Rhodes Slide (NRS), where unusual 3-4 m waves were registered on 24 March 2002, provoking some damage in the coastal stretch of the city of Rhodes (Papadopoulos et al., 2007). The event was not associated with earthquake occurrence, and eyewitnesses supported the hypothesis of a non-seismic source for the tsunami, placed 1 km offshore. Subsequent marine geophysical surveys (Sakellariou et al., 2002) evidenced the presence of several detachment niches at about 300-400 m depth along the northern steep slope, one of which can be considered responsible of the observed tsunami, fitting with the previously mentioned supposition. In this work, that is carried out in the frame of the European funded project NearToWarn, we evaluated the tsunami effects due to the NRS by means of numerical modelling: after having reconstructed the sliding body basing on morphological assumptions (obtaining an esteemed volume of 33 million m3), we simulated the sliding motion through the in-house built code UBO-BLOCK1, adopting a Lagrangian approach and splitting the sliding mass into a "chain" of interacting blocks. This provides the complete dynamics of the landslide, including the shape changes that relevantly influence the tsunami generation. After the application of an intermediate code, accounting for the slide impulse filtering through the water depth, the tsunami propagation in the sea around the island of Rhodes and up to near coasts of Turkey was simulated via the

  2. Tsunami evacuation mathematical model for the city of Padang

    SciTech Connect

    Kusdiantara, R.; Hadianti, R.; Badri Kusuma, M. S.

    2012-05-22

    Tsunami is a series of wave trains which travels with high speed on the sea surface. This traveling wave is caused by the displacement of a large volume of water after the occurrence of an underwater earthquake or volcano eruptions. The speed of tsunami decreases when it reaches the sea shore along with the increase of its amplitudes. Two large tsunamis had occurred in the last decades in Indonesia with huge casualties and large damages. Indonesian Tsunami Early Warning System has been installed along the west coast of Sumatra. This early warning system will give about 10-15 minutes to evacuatemore » people from high risk regions to the safe areas. Here in this paper, a mathematical model for Tsunami evacuation is presented with the city of Padang as a study case. In the model, the safe areas are chosen from the existing and selected high rise buildings, low risk region with relatively high altitude and (proposed to be built) a flyover ring road. Each gathering points are located in the radius of approximately 1 km from the ring road. The model is formulated as an optimization problem with the total normalized evacuation time as the objective function. The constraints consist of maximum allowable evacuation time in each route, maximum capacity of each safe area, and the number of people to be evacuated. The optimization problem is solved numerically using linear programming method with Matlab. Numerical results are shown for various evacuation scenarios for the city of Padang.« less

  3. A tsunami early warning system for the coastal area modeling

    NASA Astrophysics Data System (ADS)

    Soebroto, Arief Andy; Sunaryo, Suhartanto, Ery

    2015-04-01

    The tsunami disaster is a potential disaster in the territory of Indonesia. Indonesia is an archipelago country and close to the ocean deep. The tsunami occurred in Aceh province in 2004. Early prevention efforts have been carried out. One of them is making "tsunami buoy" which has been developed by BPPT. The tool puts sensors on the ocean floor near the coast to detect earthquakes on the ocean floor. Detection results are transmitted via satellite by a transmitter placed floating on the sea surface. The tool will cost billions of dollars for each system. Another constraint was the transmitter theft "tsunami buoy" in the absence of guard. In this study of the system has a transmission system using radio frequency and focused on coastal areas where costs are cheaper, so that it can be applied at many beaches in Indonesia are potentially affected by the tsunami. The monitoring system sends the detection results to the warning system using a radio frequency with a capability within 3 Km. Test results on the sub module sensor monitoring system generates an error of 0.63% was taken 10% showed a good quality sensing. The test results of data transmission from the transceiver of monitoring system to the receiver of warning system produces 100% successful delivery and reception of data. The test results on the whole system to function 100% properly.

  4. Observations and Numerical Modeling of the 2012 Haida Gwaii Tsunami off the Coast of British Columbia

    NASA Astrophysics Data System (ADS)

    Fine, Isaac V.; Cherniawsky, Josef Y.; Thomson, Richard E.; Rabinovich, Alexander B.; Krassovski, Maxim V.

    2015-03-01

    A major ( M w 7.7) earthquake occurred on October 28, 2012 along the Queen Charlotte Fault Zone off the west coast of Haida Gwaii (formerly the Queen Charlotte Islands). The earthquake was the second strongest instrumentally recorded earthquake in Canadian history and generated the largest local tsunami ever recorded on the coast of British Columbia. A field survey on the Pacific side of Haida Gwaii revealed maximum runup heights of up to 7.6 m at sites sheltered from storm waves and 13 m in a small inlet that is less sheltered from storms (L eonard and B ednarski 2014). The tsunami was recorded by tide gauges along the coast of British Columbia, by open-ocean bottom pressure sensors of the NEPTUNE facility at Ocean Networks Canada's cabled observatory located seaward of southwestern Vancouver Island, and by several DART stations located in the northeast Pacific. The tsunami observations, in combination with rigorous numerical modeling, enabled us to determine the physical properties of this event and to correct the location of the tsunami source with respect to the initial geophysical estimates. The initial model results were used to specify sites of particular interest for post-tsunami field surveys on the coast of Moresby Island (Haida Gwaii), while field survey observations (L eonard and B ednarski 2014) were used, in turn, to verify the numerical simulations based on the corrected source region.

  5. Tsunami hazard assessment along the French Mediterranean coast : detailed modeling of tsunami impacts for the ALDES project

    NASA Astrophysics Data System (ADS)

    Quentel, E.; Loevenbruck, A.; Hébert, H.

    2012-04-01

    The catastrophic 2004 tsunami drew the international community's attention to tsunami risk in all basins where tsunamis occurred but no warning system exists. Consequently, under the coordination of UNESCO, France decided to create a regional center, called CENALT, for the north-east Atlantic and the western Mediterranean. This warning system, which should be operational by 2012, is set up by the CEA in collaboration with the SHOM and the CNRS. The French authorities are in charge of the top-down alert system including the local alert dissemination. In order to prepare the appropriate means and measures, they initiated the ALDES (Alerte Descendante) project to which the CEA also contributes. It aims at examining along the French Mediterranean coast the tsunami risk related to earthquakes and landslides. In addition to the evaluation at regional scale, it includes the detailed studies of 3 selected sites; the local alert system will be designed for one of them : the French Riviera. In this project, our main task at CEA consists in assessing tsunami hazard related to seismic sources using numerical modeling. Past tsunamis have affected the west Mediterranean coast but are too few and poorly documented to provide a suitable database. Thus, a synthesis of earthquakes representative of the tsunamigenic seismic activity and prone to induce the largest impact to the French coast is performed based on historical data, seismotectonics and first order models. The North Africa Margin, the Ligurian and the South Tyrrhenian Seas are considered as the main tsunamigenic zones. In order to forecast the most important plausible effects, the magnitudes are estimated by enhancing to some extent the largest known values. Our hazard estimation is based on the simulation of the induced tsunamis scenarios performed with the CEA code. The 3 sites have been chosen according to the regional hazard studies, coastal typology elements and the appropriate DTMs (Digital Terrain Models). The

  6. A Tsunami Model for Chile for (Re) Insurance Purposes

    NASA Astrophysics Data System (ADS)

    Arango, Cristina; Rara, Vaclav; Puncochar, Petr; Trendafiloski, Goran; Ewing, Chris; Podlaha, Adam; Vatvani, Deepak; van Ormondt, Maarten; Chandler, Adrian

    2014-05-01

    Catastrophe models help (re)insurers to understand the financial implications of catastrophic events such as earthquakes and tsunamis. In earthquake-prone regions such as Chile,(re)insurers need more sophisticated tools to quantify the risks facing their businesses, including models with the ability to estimate secondary losses. The 2010 (M8.8) Maule (Chile) earthquake highlighted the need for quantifying losses from secondary perils such as tsunamis, which can contribute to the overall event losses but are not often modelled. This paper presents some key modelling aspects of a new earthquake catastrophe model for Chile developed by Impact Forecasting in collaboration with Aon Benfield Research partners, focusing on the tsunami component. The model has the capability to model tsunami as a secondary peril - losses due to earthquake (ground-shaking) and induced tsunamis along the Chilean coast are quantified in a probabilistic manner, and also for historical scenarios. The model is implemented in the IF catastrophe modelling platform, ELEMENTS. The probabilistic modelling of earthquake-induced tsunamis uses a stochastic event set that is consistent with the seismic (ground shaking) hazard developed for Chile, representing simulations of earthquake occurrence patterns for the region. Criteria for selecting tsunamigenic events (from the stochastic event set) are proposed which take into consideration earthquake location, depth and the resulting seabed vertical displacement and tsunami inundation depths at the coast. The source modelling software RuptGen by Babeyko (2007) was used to calculate static seabed vertical displacement resulting from earthquake slip. More than 3,600 events were selected for tsunami simulations. Deep and shallow water wave propagation is modelled using the Delft3D modelling suite, which is a state-of-the-art software developed by Deltares. The Delft3D-FLOW module is used in 2-dimensional hydrodynamic simulation settings with non-steady flow

  7. Role of sediment transport model to improve the tsunami numerical simulation

    NASA Astrophysics Data System (ADS)

    Sugawara, D.; Yamashita, K.; Takahashi, T.; Imamura, F.

    2015-12-01

    Are we overlooking an important factor for improved numerical prediction of tsunamis in shallow sea to onshore? In this presentation, several case studies on numerical modeling of tsunami-induced sediment transport are reviewed, and the role of sediment transport models for tsunami inundation simulation is discussed. Large-scale sediment transport and resulting geomorphological change occurred in the coastal areas of Tohoku, Japan, due to the 2011 Tohoku Earthquake Tsunami. Datasets obtained after the tsunami, including geomorphological and sedimentological data as well as hydrodynamic records, allows us to validate the numerical model in detail. The numerical modeling of the sediment transport by the 2011 tsunami depicted the severest erosion of sandy beach, as well as characteristic spatial patterns of erosion and deposition on the seafloor, which have taken place in Hirota Bay, Sanriku Coast. Quantitative comparisons of observation and simulation of the geomorphological changes in Sanriku Coast and Sendai Bay showed that the numerical model can predict the volumes of erosion and deposition with a right order. In addition, comparison of the simulation with aerial video footages demonstrated the numerical model is capable of tracking the overall processes of tsunami sediment transport. Although tsunami-induced sediment erosion and deposition sometimes cause significant geomorphological change, and may enhance tsunami hydrodynamic impact to the coastal zones, most tsunami simulations do not include sediment transport modeling. A coupled modeling of tsunami hydrodynamics and sediment transport draws a different picture of tsunami hazard, comparing with simple hydrodynamic modeling of tsunami inundation. Since tsunami-induced erosion, deposition and geomorphological change sometimes extend more than several kilometers across the coastline, two-dimensional horizontal model are typically used for the computation of tsunami hydrodynamics and sediment transport

  8. Scenario-based numerical modelling and the palaeo-historic record of tsunamis in Wallis and Futuna, Southwest Pacific

    NASA Astrophysics Data System (ADS)

    Lamarche, G.; Popinet, S.; Pelletier, B.; Mountjoy, J.; Goff, J.; Delaux, S.; Bind, J.

    2015-08-01

    We investigated the tsunami hazard in the remote French territory of Wallis and Futuna, Southwest Pacific, using the Gerris flow solver to produce numerical models of tsunami generation, propagation and inundation. Wallis consists of the inhabited volcanic island of Uvéa that is surrounded by a lagoon delimited by a barrier reef. Futuna and the island of Alofi form the Horn Archipelago located ca. 240 km east of Wallis. They are surrounded by a narrow fringing reef. Futuna and Alofi emerge from the North Fiji Transform Fault that marks the seismically active Pacific-Australia plate boundary. We generated 15 tsunami scenarios. For each, we calculated maximum wave elevation (MWE), inundation distance and expected time of arrival (ETA). The tsunami sources were local, regional and distant earthquake faults located along the Pacific Rim. In Wallis, the outer reef may experience 6.8 m-high MWE. Uvéa is protected by the barrier reef and the lagoon, but inundation depths of 2-3 m occur in several coastal areas. In Futuna, flow depths exceeding 2 m are modelled in several populated areas, and have been confirmed by a post-September 2009 South Pacific tsunami survey. The channel between the islands of Futuna and Alofi amplified the 2009 tsunami, which resulted in inundation distance of almost 100 m and MWE of 4.4 m. This first ever tsunami hazard modelling study of Wallis and Futuna compares well with palaeotsunamis recognised on both islands and observation of the impact of the 2009 South Pacific tsunami. The study provides evidence for the mitigating effect of barrier and fringing reefs from tsunamis.

  9. Scenario-based numerical modelling and the palaeo-historic record of tsunamis in Wallis and Futuna, Southwest Pacific

    NASA Astrophysics Data System (ADS)

    Lamarche, G.; Popinet, S.; Pelletier, B.; Mountjoy, J.; Goff, J.; Delaux, S.; Bind, J.

    2015-04-01

    We investigated the tsunami hazard in the remote French territory of Wallis and Futuna, Southwest Pacific, using the Gerris flow solver to produce numerical models of tsunami generation, propagation and inundation. Wallis consists of the inhabited volcanic island of Uvéa that is surrounded by a lagoon delimited by a barrier reef. Futuna and the island of Alofi forms the Horn Archipelago located ca. 240 km east of Wallis. They are surrounded by a narrow fringing reef. Futuna and Alofi emerge from the North Fiji Transform Fault that marks the seismically active Pacific-Australia plate boundary. We generated fifteen tsunami scenarios. For each, we calculated maximum wave elevation (MWE), inundation distance, and Expected Time of Arrival (ETA). The tsunami sources were local, regional and distant earthquake faults located along the Pacific Rim. In Wallis, the outer reef may experience 6.8 m-high MWE. Uvéa is protected by the barrier reef and the lagoon, but inundation depths of 2-3 m occur in several coastal areas. In Futuna, flow depths exceeding 2 m are modelled in several populated areas, and have been confirmed by a post-September 2009 South Pacific tsunami survey. The channel between the islands of Futuna and Alofi amplified the 2009 tsunami, which resulted in inundation distance of almost 100 m and MWE of 4.4 m. This first-ever tsunami hazard modelling study of Wallis and Futuna compares well with palaeotsunamis recognised on both islands and observation of the impact of the 2009 South Pacific tsunami. The study provides evidence for the mitigating effect of barrier and fringing reefs from tsunamis.

  10. Assessing tsunami-induced groundwater salinization and its temporal change: a numerical modelling study on the Niijima Island, Japan

    NASA Astrophysics Data System (ADS)

    Liu, Jiaqi; Tokunaga, Tomochika

    2016-04-01

    Groundwater is vulnerable to many natural hazards, including tsunami. As reported after the 2004 Indian Ocean earthquake and the 2011 Great East Japan earthquake, the generated massive tsunami inundations resulted in unexpected groundwater salinization in coastal areas. Water supply was strongly disturbed due to the significantly elevated salinity in groundwater. Supplying fresh water is one of the prioritized concerns in the immediate aftermath of disaster, and during long-term post-disaster reconstruction as well. The aim of this study is to assess the impact of tsunami on coastal groundwater system and provide guidelines on managing water resources in post-tsunami period. We selected the study area as the Niijima Island, a tsunami-prone area in Japan, which is under the risk of being attacked by a devastated tsunami with its wave height up to 30 m. A three-dimension (3-D) numerical model of the groundwater system on the Niijima Island was developed by using the simulation code FEFLOW which can handle both density- dependent groundwater flow and saturated-unsaturated flow processes. The model was justified by the measured water table data obtained from the field work in July, 2015. By using this model, we investigated saltwater intrusion and aquifer recovery process under different tsunami scenarios. Modelling results showed that saltwater could fully saturate the vadose zone and come into contact with groundwater table in just 10 mins. The 0.6 km2 of inundation area introduced salt mass equivalent to approximately 9×104 t of NaCl into the vadose zone. After the retreat of tsunami waves, the remained saltwater in vadose zone continuously intruded into the groundwater and dramatically salinized the aquifer up to about 10,000 mg/L. In the worst tsunami scenario, it took more than 10 years for the polluted aquifer to be entirely recovered by natural rainfall. Given that the groundwater is the only freshwater source on the Niijima Island, we can provide suggestions

  11. Modelling tsunami inundation for risk analysis at the Andaman Sea Coast of Thailand

    NASA Astrophysics Data System (ADS)

    Kaiser, G.; Kortenhaus, A.

    2009-04-01

    The mega-tsunami of Dec. 26, 2004 strongly impacted the Andaman Sea coast of Thailand and devastated coastal ecosystems as well as towns, settlements and tourism resorts. In addition to the tragic loss of many lives, the destruction or damage of life-supporting infrastructure, such as buildings, roads, water & power supply etc. caused high economic losses in the region. To mitigate future tsunami impacts there is a need to assess the tsunami hazard and vulnerability in flood prone areas at the Andaman Sea coast in order to determine the spatial distribution of risk and to develop risk management strategies. In the bilateral German-Thai project TRAIT research is performed on integrated risk assessment for the Provinces Phang Nga and Phuket in southern Thailand, including a hazard analysis, i.e. modelling tsunami propagation to the coast, tsunami wave breaking and inundation characteristics, as well as vulnerability analysis of the socio-economic and the ecological system in order to determine the scenario-based, specific risk for the region. In this presentation results of the hazard analysis and the inundation simulation are presented and discussed. Numerical modelling of tsunami propagation and inundation simulation is an inevitable tool for risk analysis, risk management and evacuation planning. While numerous investigations have been made to model tsunami wave generation and propagation in the Indian Ocean, there is still a lack in determining detailed inundation patterns, i.e. water depth and flow dynamics. However, for risk management and evacuation planning this knowledge is essential. As the accuracy of the inundation simulation is strongly depending on the available bathymetric and the topographic data, a multi-scale approach is chosen in this work. The ETOPO Global Relief Model as a bathymetric basis and the Shuttle Radar Topography Mission (SRTM90) have been widely applied in tsunami modelling approaches as these data are free and almost world

  12. A well-balanced meshless tsunami propagation and inundation model

    NASA Astrophysics Data System (ADS)

    Brecht, Rüdiger; Bihlo, Alexander; MacLachlan, Scott; Behrens, Jörn

    2018-05-01

    We present a novel meshless tsunami propagation and inundation model. We discretize the nonlinear shallow-water equations using a well-balanced scheme relying on radial basis function based finite differences. For the inundation model, radial basis functions are used to extrapolate the dry region from nearby wet points. Numerical results against standard one- and two-dimensional benchmarks are presented.

  13. The November 15, 2006 Kuril Islands-Generated Tsunami in Crescent City, California

    NASA Astrophysics Data System (ADS)

    Dengler, L.; Uslu, B.; Barberopoulou, A.; Yim, S. C.; Kelly, A.

    2009-02-01

    On November 15, 2006, Crescent City in Del Norte County, California was hit by a tsunami generated by a M w 8.3 earthquake in the central Kuril Islands. Strong currents that persisted over an eight-hour period damaged floating docks and several boats and caused an estimated 9.2 million in losses. Initial tsunami alert bulletins issued by the West Coast Alaska Tsunami Warning Center (WCATWC) in Palmer, Alaska were cancelled about three and a half hours after the earthquake, nearly five hours before the first surges reached Crescent City. The largest amplitude wave, 1.76-meter peak to trough, was the sixth cycle and arrived over two hours after the first wave. Strong currents estimated at over 10 knots, damaged or destroyed three docks and caused cracks in most of the remaining docks. As a result of the November 15 event, WCATWC changed the definition of Advisory from a region-wide alert bulletin meaning that a potential tsunami is 6 hours or further away to a localized alert that tsunami water heights may approach warning- level thresholds in specific, vulnerable locations like Crescent City. On January 13, 2007 a similar Kuril event occurred and hourly conferences between the warning center and regional weather forecasts were held with a considerable improvement in the flow of information to local coastal jurisdictions. The event highlighted the vulnerability of harbors from a relatively modest tsunami and underscored the need to improve public education regarding the duration of the tsunami hazards, improve dialog between tsunami warning centers and local jurisdictions, and better understand the currents produced by tsunamis in harbors.

  14. Holocene tsunamigenic sediments and tsunami modelling in the Thermaikos Gulf area (northern Greece)

    NASA Astrophysics Data System (ADS)

    Reicherter, Klaus; Papanikolaou, Ioannis D.; Roger, Jean; Grützner, Christoph; Stamatis, Georgios; Papanikolaou, Dimitrios

    2010-05-01

    Shallow drill cores in flat and southerly exposed coastal areas around the Thermaikos Gulf (Thessalonica, northern Greece) provided evidence for past high energy sedimentary events, which are interpreted as tsunamites. A tsunamigenic source is located along the western tip of the North Anatolian Fault Zone (NAFZ) in the North Aegean Basin, where water depths ranging between 1.200 and 1.650 m are sufficiently deep to generate tsunamis. However, the event layers up to now cannot be assigned to individual seismic or landslide sources, but the potential of a tsunami threat in the Thermaikos Gulf area can now be tested, following both sedimentological and modelling processes. Such potential threat regarding the Thermaikos Gulf has only recently been notified but never tested and studied in depth. As a result, several Holocene coarse clastic layers have been found intercalated in clayey or gypsiferous lagoonal deposits. These layers have erosive bases, show fining-up and thinning-up sequences, and include shell debris, foraminifera and rip-up clasts of lagoonal sediments. A widely observed significant feature of these layers involves mud-coated beach clasts, clasts that rework the high-plasticity clays of lagoons. Such features that indicate highly disturbed sedimentological condition (hyperpyncal flows) are rarely described elsewhere. Multiple intercalations of these layers with all the mentioned indicative features downhole are interpreted paleotsunami deposits from tsunamis generated by earthquakes or earthquake-triggered submarine landslides triggered by seismic shaking in the Thermaikos Gulf. Modelling of the tsunami potential of the basin-bounding fault southwards of the Thermaikos Gulf provides an example for possible tsunami generation at only one segment of NAFZ along an approx. 55 km normal fault at the southern fault-bound margin of the North Aegean Basin. The Herodotus Histories report on inundations and sea withdrawals occurring during the Greek-Persian war

  15. Non-linear resonant coupling of tsunami edge waves using stochastic earthquake source models

    USGS Publications Warehouse

    Geist, Eric L.

    2016-01-01

    Non-linear resonant coupling of edge waves can occur with tsunamis generated by large-magnitude subduction zone earthquakes. Earthquake rupture zones that straddle beneath the coastline of continental margins are particularly efficient at generating tsunami edge waves. Using a stochastic model for earthquake slip, it is shown that a wide range of edge-wave modes and wavenumbers can be excited, depending on the variability of slip. If two modes are present that satisfy resonance conditions, then a third mode can gradually increase in amplitude over time, even if the earthquake did not originally excite that edge-wave mode. These three edge waves form a resonant triad that can cause unexpected variations in tsunami amplitude long after the first arrival. An M ∼ 9, 1100 km-long continental subduction zone earthquake is considered as a test case. For the least-variable slip examined involving a Gaussian random variable, the dominant resonant triad includes a high-amplitude fundamental mode wave with wavenumber associated with the along-strike dimension of rupture. The two other waves that make up this triad include subharmonic waves, one of fundamental mode and the other of mode 2 or 3. For the most variable slip examined involving a Cauchy-distributed random variable, the dominant triads involve higher wavenumbers and modes because subevents, rather than the overall rupture dimension, control the excitation of edge waves. Calculation of the resonant period for energy transfer determines which cases resonant coupling may be instrumentally observed. For low-mode triads, the maximum transfer of energy occurs approximately 20–30 wave periods after the first arrival and thus may be observed prior to the tsunami coda being completely attenuated. Therefore, under certain circumstances the necessary ingredients for resonant coupling of tsunami edge waves exist, indicating that resonant triads may be observable and implicated in late, large-amplitude tsunami arrivals.

  16. Submarine landslide as the source for the October 11, 1918 Mona Passage tsunami: Observations and modeling

    USGS Publications Warehouse

    López-Venegas, A.M.; ten Brink, Uri S.; Geist, Eric L.

    2008-01-01

    The October 11, 1918 ML 7.5 earthquake in the Mona Passage between Hispaniola and Puerto Rico generated a local tsunami that claimed approximately 100 lives along the western coast of Puerto Rico. The area affected by this tsunami is now significantly more populated. Newly acquired high-resolution bathymetry and seismic reflection lines in the Mona Passage show a fresh submarine landslide 15 km northwest of Rinćon in northwestern Puerto Rico and in the vicinity of the first published earthquake epicenter. The landslide area is approximately 76 km2 and probably displaced a total volume of 10 km3. The landslide's headscarp is at a water depth of 1200 m, with the debris flow extending to a water depth of 4200 m. Submarine telegraph cables were reported cut by a landslide in this area following the earthquake, further suggesting that the landslide was the result of the October 11, 1918 earthquake. On the other hand, the location of the previously suggested source of the 1918 tsunami, a normal fault along the east wall of Mona Rift, does not show recent seafloor rupture. Using the extended, weakly non-linear hydrodynamic equations implemented in the program COULWAVE, we modeled the tsunami as generated by a landslide with a duration of 325 s (corresponding to an average speed of ~ 27 m/s) and with the observed dimensions and location. Calculated marigrams show a leading depression wave followed by a maximum positive amplitude in agreement with the reported polarity, relative amplitudes, and arrival times. Our results suggest this newly-identified landslide, which was likely triggered by the 1918 earthquake, was the primary cause of the October 11, 1918 tsunami and not the earthquake itself. Results from this study should be useful to help discern poorly constrained tsunami sources in other case studies.

  17. Implications of the 26 December 2004 Sumatra-Andaman earthquake on tsunami forecast and assessment models for great subduction-zone earthquakes

    USGS Publications Warehouse

    Geist, Eric L.; Titov, Vasily V.; Arcas, Diego; Pollitz, Fred F.; Bilek, Susan L.

    2007-01-01

    Results from different tsunami forecasting and hazard assessment models are compared with observed tsunami wave heights from the 26 December 2004 Indian Ocean tsunami. Forecast models are based on initial earthquake information and are used to estimate tsunami wave heights during propagation. An empirical forecast relationship based only on seismic moment provides a close estimate to the observed mean regional and maximum local tsunami runup heights for the 2004 Indian Ocean tsunami but underestimates mean regional tsunami heights at azimuths in line with the tsunami beaming pattern (e.g., Sri Lanka, Thailand). Standard forecast models developed from subfault discretization of earthquake rupture, in which deep- ocean sea level observations are used to constrain slip, are also tested. Forecast models of this type use tsunami time-series measurements at points in the deep ocean. As a proxy for the 2004 Indian Ocean tsunami, a transect of deep-ocean tsunami amplitudes recorded by satellite altimetry is used to constrain slip along four subfaults of the M >9 Sumatra–Andaman earthquake. This proxy model performs well in comparison to observed tsunami wave heights, travel times, and inundation patterns at Banda Aceh. Hypothetical tsunami hazard assessments models based on end- member estimates for average slip and rupture length (Mw 9.0–9.3) are compared with tsunami observations. Using average slip (low end member) and rupture length (high end member) (Mw 9.14) consistent with many seismic, geodetic, and tsunami inversions adequately estimates tsunami runup in most regions, except the extreme runup in the western Aceh province. The high slip that occurred in the southern part of the rupture zone linked to runup in this location is a larger fluctuation than expected from standard stochastic slip models. In addition, excess moment release (∼9%) deduced from geodetic studies in comparison to seismic moment estimates may generate additional tsunami energy, if the

  18. Numerical modeling of marine Gravity data for tsunami hazard zone mapping

    NASA Astrophysics Data System (ADS)

    Porwal, Nipun

    2012-07-01

    Tsunami is a series of ocean wave with very high wavelengths ranges from 10 to 500 km. Therefore tsunamis act as shallow water waves and hard to predict from various methods. Bottom Pressure Recorders of Poseidon class considered as a preeminent method to detect tsunami waves but Acoustic Modem in Ocean Bottom Pressure (OBP) sensors placed in the vicinity of trenches having depth of more than 6000m fails to propel OBP data to Surface Buoys. Therefore this paper is developed for numerical modeling of Gravity field coefficients from Bureau Gravimetric International (BGI) which do not play a central role in the study of geodesy, satellite orbit computation, & geophysics but by mathematical transformation of gravity field coefficients using Normalized Legendre Polynomial high resolution ocean bottom pressure (OBP) data is generated. Real time sea level monitored OBP data of 0.3° by 1° spatial resolution using Kalman filter (kf080) for past 10 years by Estimating the Circulation and Climate of the Ocean (ECCO) has been correlated with OBP data from gravity field coefficients which attribute a feasible study on future tsunami detection system from space and in identification of most suitable sites to place OBP sensors near deep trenches. The Levitus Climatological temperature and salinity are assimilated into the version of the MITGCM using the ad-joint method to obtain the sea height segment. Then TOPEX/Poseidon satellite altimeter, surface momentum, heat, and freshwater fluxes from NCEP reanalysis product and the dynamic ocean topography DOT_DNSCMSS08_EGM08 is used to interpret sea-bottom elevation. Then all datasets are associated under raster calculator in ArcGIS 9.3 using Boolean Intersection Algebra Method and proximal analysis tools with high resolution sea floor topographic map. Afterward tsunami prone area and suitable sites for set up of BPR as analyzed in this research is authenticated by using Passive microwave radiometry system for Tsunami Hazard Zone

  19. Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska

    USGS Publications Warehouse

    Waythomas, C.F.; Watts, P.; Walder, J.S.

    2006-01-01

    Many of the world's active volcanoes are situated on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, and lahars, can deliver large volumes of unconsolidated debris to the ocean in a short period of time and thereby generate tsunamis. Deposits of both hot and cold volcanic mass flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and Cook Inlet, indicating that the flows entered the sea and in some cases may have initiated tsunamis. We evaluate the process of tsunami generation by cold granular subaerial volcanic mass flows using examples from Augustine Volcano in southern Cook Inlet. Augustine Volcano is the most historically active volcano in the Cook Inlet region, and future eruptions, should they lead to debris-avalanche formation and tsunami generation, could be hazardous to some coastal areas. Geological investigations at Augustine Volcano suggest that as many as 12-14 debris avalanches have reached the sea in the last 2000 years, and a debris avalanche emplaced during an A.D. 1883 eruption may have initiated a tsunami that was observed about 80 km east of the volcano at the village of English Bay (Nanwalek) on the coast of the southern Kenai Peninsula. Numerical simulation of mass-flow motion, tsunami generation, propagation, and inundation for Augustine Volcano indicate only modest wave generation by volcanic mass flows and localized wave effects. However, for east-directed mass flows entering Cook Inlet, tsunamis are capable of reaching the more populated coastlines of the southwestern Kenai Peninsula, where maximum water amplitudes of several meters are possible.

  20. Combined effects of tectonic and landslide-generated Tsunami Runup at Seward, Alaska during the Mw 9.2 1964 earthquake

    USGS Publications Warehouse

    Suleimani, E.; Nicolsky, D.J.; Haeussler, Peter J.; Hansen, R.

    2011-01-01

    We apply a recently developed and validated numerical model of tsunami propagation and runup to study the inundation of Resurrection Bay and the town of Seward by the 1964 Alaska tsunami. Seward was hit by both tectonic and landslide-generated tsunami waves during the Mw 9.2 1964 mega thrust earthquake. The earthquake triggered a series of submarine mass failures around the fjord, which resulted in land sliding of part of the coastline into the water, along with the loss of the port facilities. These submarine mass failures generated local waves in the bay within 5 min of the beginning of strong ground motion. Recent studies estimate the total volume of underwater slide material that moved in Resurrection Bay to be about 211 million m3 (Haeussler et al. in Submarine mass movements and their consequences, pp 269-278, 2007). The first tectonic tsunami wave arrived in Resurrection Bay about 30 min after the main shock and was about the same height as the local landslide-generated waves. Our previous numerical study, which focused only on the local land slide generated waves in Resurrection Bay, demonstrated that they were produced by a number of different slope failures, and estimated relative contributions of different submarine slide complexes into tsunami amplitudes (Suleimani et al. in Pure Appl Geophys 166:131-152, 2009). This work extends the previous study by calculating tsunami inundation in Resurrection Bay caused by the combined impact of landslide-generated waves and the tectonic tsunami, and comparing the composite inundation area with observations. To simulate landslide tsunami runup in Seward, we use a viscous slide model of Jiang and LeBlond (J Phys Oceanogr 24(3):559-572, 1994) coupled with nonlinear shallow water equations. The input data set includes a high resolution multibeam bathymetry and LIDAR topography grid of Resurrection Bay, and an initial thickness of slide material based on pre- and post-earthquake bathymetry difference maps. For

  1. The 2017 México Tsunami Record, Numerical Modeling and Threat Assessment in Costa Rica

    NASA Astrophysics Data System (ADS)

    Chacón-Barrantes, Silvia

    2018-03-01

    An M w 8.2 earthquake and tsunami occurred offshore the Pacific coast of México on 2017-09-08, at 04:49 UTC. Costa Rican tide gauges have registered a total of 21 local, regional and far-field tsunamis. The Quepos gauge registered 12 tsunamis between 1960 and 2014 before it was relocated inside a harbor by late 2014, where it registered two more tsunamis. This paper analyzes the 2017 México tsunami as recorded by the Quepos gauge. It took 2 h for the tsunami to arrive to Quepos, with a first peak height of 9.35 cm and a maximum amplitude of 18.8 cm occurring about 6 h later. As a decision support tool, this tsunami was modeled for Quepos in real time using ComMIT (Community Model Interface for Tsunami) with the finer grid having a resolution of 1 arcsec ( 30 m). However, the model did not replicate the tsunami record well, probably due to the lack of a finer and more accurate bathymetry. In 2014, the National Tsunami Monitoring System of Costa Rica (SINAMOT) was created, acting as a national tsunami warning center. The occurrence of the 2017 México tsunami raised concerns about warning dissemination mechanisms for most coastal communities in Costa Rica, due to its short travel time.

  2. Multi-scale modeling of tsunami flows and tsunami-induced forces

    NASA Astrophysics Data System (ADS)

    Qin, X.; Motley, M. R.; LeVeque, R. J.; Gonzalez, F. I.

    2016-12-01

    The modeling of tsunami flows and tsunami-induced forces in coastal communities with the incorporation of the constructed environment is challenging for many numerical modelers because of the scale and complexity of the physical problem. A two-dimensional (2D) depth-averaged model can be efficient for modeling of waves offshore but may not be accurate enough to predict the complex flow with transient variance in vertical direction around constructed environments on land. On the other hand, using a more complex three-dimensional model is much more computational expensive and can become impractical due to the size of the problem and the meshing requirements near the built environment. In this study, a 2D depth-integrated model and a 3D Reynolds Averaged Navier-Stokes (RANS) model are built to model a 1:50 model-scale, idealized community, representative of Seaside, OR, USA, for which existing experimental data is available for comparison. Numerical results from the two numerical models are compared with each other as well as experimental measurement. Both models predict the flow parameters (water level, velocity, and momentum flux in the vicinity of the buildings) accurately, in general, except for time period near the initial impact, where the depth-averaged models can fail to capture the complexities in the flow. Forces predicted using direct integration of predicted pressure on structural surfaces from the 3D model and using momentum flux from the 2D model with constructed environment are compared, which indicates that force prediction from the 2D model is not always reliable in such a complicated case. Force predictions from integration of the pressure are also compared with forces predicted from bare earth momentum flux calculations to reveal the importance of incorporating the constructed environment in force prediction models.

  3. The October 11, 1918 Mona Passage tsunami modeled using new submarine landslide evidence.

    NASA Astrophysics Data System (ADS)

    López, A. M.; ten Brink, U.; Geist, E.

    2007-12-01

    The October 11, 1918 ML 7.5 earthquake in the Mona Passage betweeen Hispaniola and Puerto Rico generated a local tsunami that claimed approximately 100 lives along the western coast of Puerto Rico. The area affected by this tsunami is now many-fold more populated. Although the exact cause of the tsunami is still unclear, newly-acquired high-resolution bathymetry of the Mona Passage and seismic reflection lines show a fresh submarine landslide 12 km northwest of Rincón in northwestern Puerto Rico and in the vicinity of the earthquake epicenter determined by Doser et al., (2005). The landslide area is approximately 76 km2 and probably displaced a total volume of 10 km3. The landslide's head scarp is at a water depth of 1.2 km, with the debris flow extending down to a water depth of 4.5 km. The seismic profiles and multibeam bathymetry indicate that the previously suggested source of the 1918 tsunami, a normal fault along the east side of Mona Rift (Mercado and McCann, 1998), was not active recently. The fault escarpment along Desecheo Ridge, which is near the Doser et al., (2005) epicenter, and our landslide appear, on the other hand, to be rather fresh. Using the extended, weakly non-linear hydrodynamic equations implemented in the program COULWAVE (Lynett and Liu, 2002), we modeled the tsunami by a landslide with a finite duration and with the observed dimensions and location. Marigrams (time series of sea level) were calculated at locations near to reported locations of runup. The marigrams show a leading depression wave followed by a maximum positive amplitude in good agreement with the reported polarity, relative amplitudes, and arrival times. Our results suggest this newly-identified landslide, which was likely triggered by the 1918 earthquake, was the probable cause of the October 11, 1918 tsunami and not a normal fault rupture as previously suggested.

  4. Sensitivity of Tsunami Waves and Coastal Inundation/Runup to Seabed Displacement Models: Application to the Cascadia Subduction zone

    NASA Astrophysics Data System (ADS)

    Jalali Farahani, R.; Fitzenz, D. D.; Nyst, M.

    2015-12-01

    Major components of tsunami hazard modeling include earthquake source characterization, seabed displacement, wave propagation, and coastal inundation/run-up. Accurate modeling of these components is essential to identify the disaster risk exposures effectively, which would be crucial for insurance industry as well as policy makers to have tsunami resistant design of structures and evacuation planning (FEMA, 2008). In this study, the sensitivity and variability of tsunami coastal inundation due to Cascadia megathrust subduction earthquake are studied by considering the different approaches for seabed displacement model. The first approach is the analytical expressions that were proposed by Okada (1985, 1992) for the surface displacements and strains of rectangular sources. The second approach was introduced by Meade (2006) who introduced analytical solutions for calculating displacements, strains, and stresses on triangular sources. In this study, the seabed displacement using triangular representation of geometrically complex fault surfaces is compared with the Okada rectangular representations for the Cascadia subduction zone. In the triangular dislocation algorithm, the displacement is calculated using superposition of two angular dislocations for each of the three triangle legs. The triangular elements could give a better and gap-free representation of the fault surfaces. In addition, the rectangular representation gives large unphysical vertical displacement along the shallow-depth fault edge that generates unrealistic short-wavelength waves. To study the impact of these two different algorithms on the final tsunami inundation, the initial tsunami wave as well as wave propagation and the coastal inundation are simulated. To model the propagation of tsunami waves and coastal inundation, 2D shallow water equations are modeled using the seabed displacement as the initial condition for the numerical model. Tsunami numerical simulation has been performed on high

  5. Simulations and analysis of asteroid-generated tsunamis using the shallow water equations

    NASA Astrophysics Data System (ADS)

    Berger, M. J.; LeVeque, R. J.; Weiss, R.

    2016-12-01

    We discuss tsunami propagation for asteroid-generated air bursts and water impacts. We present simulations for a range of conditions using the GeoClaw simulation software. Examples include meteors that span 5 to 250 MT of kinetic energy, and use bathymetry from the U.S. coastline. We also study radially symmetric one-dimensional equations to better explore the nature and decay rate of waves generated by air burst pressure disturbances traveling at the speed of sound in air, which is much greater than the gravity wave speed of the tsunami generated. One-dimensional simulations along a transect of bathymetry are also used to explore the resolution needed for the full two-dimensional simulations, which are much more expensive even with the use of adaptive mesh refinement due to the short wave lengths of these tsunamis. For this same reason, shallow water equations may be inadequate and we also discuss dispersive effects.

  6. Modeling the propagation, transformation and the impact of tsunami on urban areas using the coupling STOC-ML/IC/CADMAS in nested grids - Application to specific sites of Chile to improve the tsunami induced loads prediction.

    NASA Astrophysics Data System (ADS)

    Mokrani, C.; Catalan, P. A.; Cienfuegos, R.; Arikawa, T.

    2016-02-01

    A large part of coasts around the world are affected by tsunami impacts, which supposes a challenge when designing coastal protection structures. Numerical models provide predictions of tsunami-induced loads and there time evolution, which can be used to improve sizing rules of coastal structures. However, the numerical assessment of impact loads is an hard stake. Indeed, recent experimental studies have shown that pressure dynamics generated during tsunami impacts are highly sensitive to the incident local shape of the tsunami. Therefore, high numerical resolutions and very accurate models are required to model all stages during which the tsunami shape is modified before the impact. Given the large distances involved in tsunami events, this can be disregarded in favor of computing time. The Port and Airport Research Institute (PARI) has recently developed a three-way coupled model which allows to accurately model the incident tsunami shape while maintaining reasonable computational time. This coupling approach uses three models used in nested grids (cf. Figure 1). The first one (STOC-ML) solves Nonlinear Shallow Water Equations with hydrostatic pressure. It is used to model the tsunami propagation off the coast. The second one (STOC-IC) is a 3D non-hydrostatic model, on which the free-surface position is estimated through the integrated continuity equation. It has shown to accurately describe dispersive and weakly linear effects occurring at the coast vicinity. The third model (CADMAS-SURF) solves fully three-dimensional Navier-Stokes equations and use a VOF method. Highly nonlinear, dispersive effects and wave breaking processes can be included at the wave scale and therefore, a very accurate description of the incident tsunami is provided. Each model have been separately validated from analytical and/or experimental data. The present objective is to highlight recent advances in Coastal Ocean modeling for tsunami modeling and loads prediction by applying this

  7. Sedimentary Record and Morphological Effects of a Landslide-Generated Tsunami in a Polar Region: The 2000 AD Tsunami in Vaigat Strait, West Greenland

    NASA Astrophysics Data System (ADS)

    Szczucinski, W.; Rosser, N. J.; Strzelecki, M. C.; Long, A. J.; Lawrence, T.; Buchwal, A.; Chague-Goff, C.; Woodroffe, S.

    2012-12-01

    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

  8. Tsunami Hazard in La Réunion Island (SW Indian Ocean): Scenario-Based Numerical Modelling on Vulnerable Coastal Sites

    NASA Astrophysics Data System (ADS)

    Allgeyer, S.; Quentel, É.; Hébert, H.; Gailler, A.; Loevenbruck, A.

    2017-08-01

    Several major tsunamis have affected the southwest Indian Ocean area since the 2004 Sumatra event, and some of them (2005, 2006, 2007 and 2010) have hit La Réunion Island in the southwest Indian Ocean. However, tsunami hazard is not well defined for La Réunion Island where vulnerable coastlines can be exposed. This study offers a first tsunami hazard assesment for La Réunion Island. We first review the historical tsunami observations made on the coastlines, where high tsunami waves (2-3 m) have been reported on the western coast, especially during the 2004 Indian Ocean tsunami. Numerical models of historical scenarios yield results consistent with available observations on the coastal sites (the harbours of La Pointe des Galets and Saint-Paul). The 1833 Pagai earthquake and tsunami can be considered as the worst-case historical scenario for this area. In a second step, we assess the tsunami exposure by covering the major subduction zones with syntethic events of constant magnitude (8.7, 9.0 and 9.3). The aggregation of magnitude 8.7 scenarios all generate strong currents in the harbours (3-7 m s^{-1}) and about 2 m of tsunami maximum height without significant inundation. The analysis of the magnitude 9.0 events confirms that the main commercial harbour (Port Est) is more vulnerable than Port Ouest and that flooding in Saint-Paul is limited to the beach area and the river mouth. Finally, the magnitude 9.3 scenarios show limited inundations close to the beach and in the riverbed in Saint-Paul. More generally, the results confirm that for La Runion, the Sumatra subduction zone is the most threatening non-local source area for tsunami generation. This study also shows that far-field coastal sites should be prepared for tsunami hazard and that further work is needed to improve operational warning procedures. Forecast methods should be developed to provide tools to enable the authorities to anticipate the local effects of tsunamis and to evacuate the harbours in

  9. Tsunami Defense Efforts at Samcheok Port, Korea

    NASA Astrophysics Data System (ADS)

    Cho, Y. S.

    2016-02-01

    Tsunamis mainly triggered by impulsive undersea motions are long waves and can propagate a long distance. Thus, they can cause huge casualties not only neighboring countries but also distant countries. Recently, several devastating tsunamis have been occurred around the Pacific Ocean rim. Among them, the Great East Japan tsunami occurred on March 11, 2011 is probably recorded as one of the most destructive tsunamis during last several decades. The Tsunami killed more than 20,000 people (including missing people) and deprived of property damage of approximately 300 billion USD. The eastern coast of the Korean Peninsula has been attacked historically by unexpected tsunami events. These tsunamis were generated by undersea earthquakes occurred off the west coast of Japan. For example, the Central East Sea Tsunami occurred on May 26, 1983 killed 3 people and caused serious property damage at Samcheok Port located at the eastern coast of Korea. Thus, a defense plan against unexpected tsunami strikes is an essential task for the port authority to protect lives of human beings and port facilities. In this study, a master plan of tsunami defense is introduced at Samcheok Port. A tsunami hazard map is also made by employing both propagation and inundation models. Detailed defense efforts are described including the procedure of development of a tsunami hazard map. Keywords: tsunami, hazard map, run-up height, emergency action plan

  10. The magnetic fields generated by the tsunami of February 27, 2010

    NASA Astrophysics Data System (ADS)

    Nair, M. C.; Maus, S.; Neetu, S.; Kuvshinov, A. V.; Chulliat, A.

    2010-12-01

    It has long been speculated that tsunamis produce measurable perturbations in the magnetic field. Recent deployments of highly accurate magnetometers and the exceptionally deep solar minimum provided ideal conditions to identify these small signals for the tsunami resulting from the strong Chilean earthquake on February 27, 2010. We find that the magnetic observatory measurements on Easter Island, 3500 km west of the epicenter, show a periodic signal of 1 nT, coincident in time with recordings from the local tide gauge. The amplitude of this signal is consistent with the sea level variation caused by the tsunami in the open ocean near Easter Island through a scaling method proposed by Tyler (2005). In order to have a better understanding of this process, we predict the magnetic fields induced by the Chile tsunami using a barotropic-shallow-water model along with a three-dimensional electromagnetic induction code (Kuvshinov et al., 2002). Initial results indicate good agreement between the predicted and observed magnetic signals at Easter Island. The detection of these magnetic signals represents a milestone in understanding tsunami-induced electromagnetic effects. However, magnetospheric disturbances could limit the practical utility of tsunami electromagnetic monitoring to periods of low solar activity.

  11. Stakeholder-driven geospatial modeling for assessing tsunami vertical-evacuation strategies in the U.S. Pacific Northwest

    NASA Astrophysics Data System (ADS)

    Wood, N. J.; Schmidtlein, M.; Schelling, J.; Jones, J.; Ng, P.

    2012-12-01

    Recent tsunami disasters, such as the 2010 Chilean and 2011 Tohoku events, demonstrate the significant life loss that can occur from tsunamis. Many coastal communities in the world are threatened by near-field tsunami hazards that may inundate low-lying areas only minutes after a tsunami begins. Geospatial integration of demographic data and hazard zones has identified potential impacts on populations in communities susceptible to near-field tsunami threats. Pedestrian-evacuation models build on these geospatial analyses to determine if individuals in tsunami-prone areas will have sufficient time to reach high ground before tsunami-wave arrival. Areas where successful evacuations are unlikely may warrant vertical-evacuation (VE) strategies, such as berms or structures designed to aid evacuation. The decision of whether and where VE strategies are warranted is complex. Such decisions require an interdisciplinary understanding of tsunami hazards, land cover conditions, demography, community vulnerability, pedestrian-evacuation models, land-use and emergency-management policy, and decision science. Engagement with the at-risk population and local emergency managers in VE planning discussions is critical because resulting strategies include permanent structures within a community and their local ownership helps ensure long-term success. We present a summary of an interdisciplinary approach to assess VE options in communities along the southwest Washington coast (U.S.A.) that are threatened by near-field tsunami hazards generated by Cascadia subduction zone earthquakes. Pedestrian-evacuation models based on an anisotropic approach that uses path-distance algorithms were merged with population data to forecast the distribution of at-risk individuals within several communities as a function of travel time to safe locations. A series of community-based workshops helped identify potential VE options in these communities, collectively known as "Project Safe Haven" at the

  12. A Collaborative Effort Between Caribbean States for Tsunami Numerical Modeling: Case Study CaribeWave15

    NASA Astrophysics Data System (ADS)

    Chacón-Barrantes, Silvia; López-Venegas, Alberto; Sánchez-Escobar, Rónald; Luque-Vergara, Néstor

    2018-04-01

    Historical records have shown that tsunami have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for Tsunamis and Other Coastal Threats for the Caribbean Sea and Adjacent Regions) of IOC/UNESCO has a modeling subgroup, which seeks to develop a modeling platform to assess the effects of possible tsunami sources within the basin. The CaribeWave tsunami exercise is carried out annually in the Caribbean region to increase awareness and test tsunami preparedness of countries within the basin. In this study we present results of tsunami inundation using the CaribeWave15 exercise scenario for four selected locations within the Caribbean basin (Colombia, Costa Rica, Panamá and Puerto Rico), performed by tsunami modeling researchers from those selected countries. The purpose of this study was to provide the states with additional results for the exercise. The results obtained here were compared to co-seismic deformation and tsunami heights within the basin (energy plots) provided for the exercise to assess the performance of the decision support tools distributed by PTWC (Pacific Tsunami Warning Center), the tsunami service provider for the Caribbean basin. However, comparison of coastal tsunami heights was not possible, due to inconsistencies between the provided fault parameters and the modeling results within the provided exercise products. Still, the modeling performed here allowed to analyze tsunami characteristics at the mentioned states from sources within the North Panamá Deformed Belt. The occurrence of a tsunami in the Caribbean may affect several countries because a great variety of them share coastal zones in this basin. Therefore, collaborative efforts similar to the one presented in this study, particularly between neighboring

  13. A Collaborative Effort Between Caribbean States for Tsunami Numerical Modeling: Case Study CaribeWave15

    NASA Astrophysics Data System (ADS)

    Chacón-Barrantes, Silvia; López-Venegas, Alberto; Sánchez-Escobar, Rónald; Luque-Vergara, Néstor

    2017-10-01

    Historical records have shown that tsunami have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for Tsunamis and Other Coastal Threats for the Caribbean Sea and Adjacent Regions) of IOC/UNESCO has a modeling subgroup, which seeks to develop a modeling platform to assess the effects of possible tsunami sources within the basin. The CaribeWave tsunami exercise is carried out annually in the Caribbean region to increase awareness and test tsunami preparedness of countries within the basin. In this study we present results of tsunami inundation using the CaribeWave15 exercise scenario for four selected locations within the Caribbean basin (Colombia, Costa Rica, Panamá and Puerto Rico), performed by tsunami modeling researchers from those selected countries. The purpose of this study was to provide the states with additional results for the exercise. The results obtained here were compared to co-seismic deformation and tsunami heights within the basin (energy plots) provided for the exercise to assess the performance of the decision support tools distributed by PTWC (Pacific Tsunami Warning Center), the tsunami service provider for the Caribbean basin. However, comparison of coastal tsunami heights was not possible, due to inconsistencies between the provided fault parameters and the modeling results within the provided exercise products. Still, the modeling performed here allowed to analyze tsunami characteristics at the mentioned states from sources within the North Panamá Deformed Belt. The occurrence of a tsunami in the Caribbean may affect several countries because a great variety of them share coastal zones in this basin. Therefore, collaborative efforts similar to the one presented in this study, particularly between neighboring

  14. Large Historical Earthquakes and Tsunami Hazards in the Western Mediterranean: Source Characteristics and Modelling

    NASA Astrophysics Data System (ADS)

    Harbi, Assia; Meghraoui, Mustapha; Belabbes, Samir; Maouche, Said

    2010-05-01

    The western Mediterranean region was the site of numerous large earthquakes in the past. Most of these earthquakes are located at the East-West trending Africa-Eurasia plate boundary and along the coastline of North Africa. The most recent recorded tsunamigenic earthquake occurred in 2003 at Zemmouri-Boumerdes (Mw 6.8) and generated ~ 2-m-high tsunami wave. The destructive wave affected the Balearic Islands and Almeria in southern Spain and Carloforte in southern Sardinia (Italy). The earthquake provided a unique opportunity to gather instrumental records of seismic waves and tide gauges in the western Mediterranean. A database that includes a historical catalogue of main events, seismic sources and related fault parameters was prepared in order to assess the tsunami hazard of this region. In addition to the analysis of the 2003 records, we study the 1790 Oran and 1856 Jijel historical tsunamigenic earthquakes (Io = IX and X, respectively) that provide detailed observations on the heights and extension of past tsunamis and damage in coastal zones. We performed the modelling of wave propagation using NAMI-DANCE code and tested different fault sources from synthetic tide gauges. We observe that the characteristics of seismic sources control the size and directivity of tsunami wave propagation on both northern and southern coasts of the western Mediterranean.

  15. Operational Tsunami Modelling with TsunAWI for the German-Indonesian Tsunami Early Warning System: Recent Developments

    NASA Astrophysics Data System (ADS)

    Rakowsky, N.; Harig, S.; Androsov, A.; Fuchs, A.; Immerz, A.; Schröter, J.; Hiller, W.

    2012-04-01

    Starting in 2005, the GITEWS project (German-Indonesian Tsunami Early Warning System) established from scratch a fully operational tsunami warning system at BMKG in Jakarta. Numerical simulations of prototypic tsunami scenarios play a decisive role in a priori risk assessment for coastal regions and in the early warning process itself. Repositories with currently 3470 regional tsunami scenarios for GITEWS and 1780 Indian Ocean wide scenarios in support of Indonesia as a Regional Tsunami Service Provider (RTSP) were computed with the non-linear shallow water modell TsunAWI. It is based on a finite element discretisation, employs unstructured grids with high resolution along the coast and includes inundation. This contribution gives an overview on the model itself, the enhancement of the model physics, and the experiences gained during the process of establishing an operational code suited for thousands of model runs. Technical aspects like computation time, disk space needed for each scenario in the repository, or post processing techniques have a much larger impact than they had in the beginning when TsunAWI started as a research code. Of course, careful testing on artificial benchmarks and real events remains essential, but furthermore, quality control for the large number of scenarios becomes an important issue.

  16. Modeling of influence from remote tsunami at the coast of Sakhalin and Kuriles islands.

    NASA Astrophysics Data System (ADS)

    Zaytsev, Andrey; Pelinovsky, Efim; Yalciner, Ahmet; Chernov, Anton; Kostenko, Irina

    2010-05-01

    The Far East coast of Russia (Kuriles islands, Sakhalin, Kamchatka) is the area where the dangerous natural phenomena as tsunami is located. A lot of works are established for decreasing of tsunami's influence. Tsunami mapping and mitigation strategy are given for some regions. The centers of Tsunami Warning System are opened, enough plenty of records of a tsunami are collected. The properties of local tsunami are studied well. At the same time, the catastrophic event of the Indonesian tsunami, which had happened in December, 2004, when the sufficient waves have reached the coasts of Africa and South America, it is necessary to note, that the coats, which was far from the epicenter of earthquakes can be effected by catastrophic influence. Moreover, it is practically unique case, when using Tsunami Warning System can reduce the number of human victims to zero. Development of the computer technologies, numerical methods for the solution of systems of the nonlinear differential equations makes computer modeling real and hypothetical tsunamis is the basic method of studying features of distribution of waves in water areas and their influence at coast. Numerical modeling of distribution of historical tsunami from the seismic sources in the Pacific Ocean was observed. The events with an epicenter, remote from Far East coast of Russia were considered. The estimation of the remote tsunami waves propagation was developed. Impact force of tsunamis was estimated. The features of passage of tsunami through Kuril Straits were considered. The spectral analysis of records in settlements of Sakhalin and Kuriles is lead. NAMI-DANCE program was used for tsunami propagation numerical modeling. It is used finite element numerical schemes for Shallow Water Equations and Nonlinear-Dispersive Equations, with use Nested Grid.

  17. Chapter 3 – Phenomenology of Tsunamis: Statistical Properties from Generation to Runup

    USGS Publications Warehouse

    Geist, Eric L.

    2015-01-01

    Observations related to tsunami generation, propagation, and runup are reviewed and described in a phenomenological framework. In the three coastal regimes considered (near-field broadside, near-field oblique, and far field), the observed maximum wave amplitude is associated with different parts of the tsunami wavefield. The maximum amplitude in the near-field broadside regime is most often associated with the direct arrival from the source, whereas in the near-field oblique regime, the maximum amplitude is most often associated with the propagation of edge waves. In the far field, the maximum amplitude is most often caused by the interaction of the tsunami coda that develops during basin-wide propagation and the nearshore response, including the excitation of edge waves, shelf modes, and resonance. Statistical distributions that describe tsunami observations are also reviewed, both in terms of spatial distributions, such as coseismic slip on the fault plane and near-field runup, and temporal distributions, such as wave amplitudes in the far field. In each case, fundamental theories of tsunami physics are heuristically used to explain the observations.

  18. The Solomon Islands Tsunami of 6 February 2013 in the Santa Cruz Islands: Field Survey and Modeling

    NASA Astrophysics Data System (ADS)

    Fritz, Hermann M.; Papantoniou, Antonios; Biukoto, Litea; Albert, Gilly; Wei, Yong

    2014-05-01

    observed on volcanic Tinakula Island and on Ndendo Island. Observations from the 2013 Santa Cruz tsunami are compared against the 2007 and 2010 Solomon Islands tsunamis. The field observations in the Santa Cruz Islands present an important dataset to assess tsunami impact in the near-source region. The tsunami was also recorded at deep-ocean tsunameters and tide gauges throughout the Pacific. These observations allow us to further investigate the physics of tsunami generation caused by the seismic process (or other non-seismic mechanisms). We use numerical model MOST to analyze the large runup and complex impact distribution caused by the Santa Cruz tsunami. Source models obtained using seismic data / tsunami data are carried out to initialize the tsunami model. MOST uses two sets of numerical grids to investigate both the near- and far-field aspects of the tsunami. The basin-scale modeling results are computed using a spatial resolution of 4 arc min (approx. 7,200 m) and compared with measurements at deep-ocean tsunameters. The near-field modeling is carried out using a series of telescoped grids up to a grid resolution of tens of meters to compare with the tsunami runup and flooding extent obtained through the field survey in the Solomon Islands. The modeling results emphasize the contrast between the tsunami impact on the exposed coastline and the sheltered Lata Bay stressing the problematic interpretation of a tsunami in progress based solely on near-source tide-gauge measurements. The team also interviewed eyewitnesses and educated residents about the tsunami hazard in numerous ad hoc presentations and discussions. The combination of ancestral knowledge and recent Solomon Islands wide geohazards education programs triggered an immediate spontaneous self-evacuation containing the death toll in the small evacuation window of few minutes between the end of the ground shaking and the onslaught of the tsunami. Fortunately school children were shown a video on the 1 April

  19. Geological Evidences for a Large Tsunami Generated by the 7.3 ka Kikai Caldera Eruption, Southern Japan

    NASA Astrophysics Data System (ADS)

    Yamada, M.; Fujino, S.; Satake, K.

    2017-12-01

    The 7.3 ka eruption of Kikai volcano, southern Kyushu, Japan, is one of the largest caldera-forming eruption in the world. Given that a huge caldera was formed in shallow sea area during the eruption, a tsunami must have been generated by a sea-level change associated. Pyroclastic flow and tsunami deposits by the eruption have been studied around the caldera, but they are not enough to evaluate the tsunami size. The goal of this study is to unravel sizes of tsunami and triggering caldera collapse by numerical simulations based on a widely-distributed tsunami deposit associated with the eruption. In this presentation, we will provide an initial data on distribution of the 7.3 ka tsunami deposit contained in sediment cores taken at three coastal lowlands in Wakayama, Tokushima, and Oita prefectures (560 km, 520 km, and 310 km north-east from the caldera, respectively). A volcanic ash from the eruption (Kikai Akahoya tephra: K-Ah) is evident in organic-rich muddy sedimentary sequence in all sediment cores. Up to 6-cm-thick sand layer, characterized by a grading structure and sharp bed boundary with lower mud, is observed immediately beneath the K-Ah tephra in all study sites. These sedimentary characteristics and broad distribution indicate that the sand layer was most likely deposited by a tsunami which can propagate to a wide area, but not by a local storm surge. Furthermore, the stratigraphic relationship implies that the study sites must have been inundated by the tsunami prior to the ash fall. A sand layer is also evident within the K-Ah tephra layer, suggesting that the sand layer was probably formed by a subsequent tsunami wave during the ash fall. These geological evidences for the 7.3 ka tsunami inundation will contribute to a better understanding of the caldera collapse and the resultant tsunami, but also of the tsunami generating system in the eruptive process.

  20. On the characteristics of landslide tsunamis

    PubMed Central

    Løvholt, F.; Pedersen, G.; Harbitz, C. B.; Glimsdal, S.; Kim, J.

    2015-01-01

    This review presents modelling techniques and processes that govern landslide tsunami generation, with emphasis on tsunamis induced by fully submerged landslides. The analysis focuses on a set of representative examples in simplified geometries demonstrating the main kinematic landslide parameters influencing initial tsunami amplitudes and wavelengths. Scaling relations from laboratory experiments for subaerial landslide tsunamis are also briefly reviewed. It is found that the landslide acceleration determines the initial tsunami elevation for translational landslides, while the landslide velocity is more important for impulsive events such as rapid slumps and subaerial landslides. Retrogressive effects stretch the tsunami, and in certain cases produce enlarged amplitudes due to positive interference. In an example involving a deformable landslide, it is found that the landslide deformation has only a weak influence on tsunamigenesis. However, more research is needed to determine how landslide flow processes that involve strong deformation and long run-out determine tsunami generation. PMID:26392615

  1. On the characteristics of landslide tsunamis.

    PubMed

    Løvholt, F; Pedersen, G; Harbitz, C B; Glimsdal, S; Kim, J

    2015-10-28

    This review presents modelling techniques and processes that govern landslide tsunami generation, with emphasis on tsunamis induced by fully submerged landslides. The analysis focuses on a set of representative examples in simplified geometries demonstrating the main kinematic landslide parameters influencing initial tsunami amplitudes and wavelengths. Scaling relations from laboratory experiments for subaerial landslide tsunamis are also briefly reviewed. It is found that the landslide acceleration determines the initial tsunami elevation for translational landslides, while the landslide velocity is more important for impulsive events such as rapid slumps and subaerial landslides. Retrogressive effects stretch the tsunami, and in certain cases produce enlarged amplitudes due to positive interference. In an example involving a deformable landslide, it is found that the landslide deformation has only a weak influence on tsunamigenesis. However, more research is needed to determine how landslide flow processes that involve strong deformation and long run-out determine tsunami generation. © 2015 The Authors.

  2. A Probabilistic Tsunami Hazard Study of the Auckland Region, Part I: Propagation Modelling and Tsunami Hazard Assessment at the Shoreline

    NASA Astrophysics Data System (ADS)

    Power, William; Wang, Xiaoming; Lane, Emily; Gillibrand, Philip

    2013-09-01

    Regional source tsunamis represent a potentially devastating threat to coastal communities in New Zealand, yet are infrequent events for which little historical information is available. It is therefore essential to develop robust methods for quantitatively estimating the hazards posed, so that effective mitigation measures can be implemented. We develop a probabilistic model for the tsunami hazard posed to the Auckland region of New Zealand from the Kermadec Trench and the southern New Hebrides Trench subduction zones. An innovative feature of our model is the systematic analysis of uncertainty regarding the magnitude-frequency distribution of earthquakes in the source regions. The methodology is first used to estimate the tsunami hazard at the coastline, and then used to produce a set of scenarios that can be applied to produce probabilistic maps of tsunami inundation for the study region; the production of these maps is described in part II. We find that the 2,500 year return period regional source tsunami hazard for the densely populated east coast of Auckland is dominated by events originating in the Kermadec Trench, while the equivalent hazard to the sparsely populated west coast is approximately equally due to events on the Kermadec Trench and the southern New Hebrides Trench.

  3. Two regions of seafloor deformation generated the tsunami for the 13 November 2016, Kaikoura, New Zealand earthquake

    NASA Astrophysics Data System (ADS)

    Bai, Yefei; Lay, Thorne; Cheung, Kwok Fai; Ye, Lingling

    2017-07-01

    The 13 November 2016 Kaikoura, New Zealand, Mw 7.8 earthquake ruptured multiple crustal faults in the transpressional Marlborough and North Canterbury tectonic domains of northeastern South Island. The Hikurangi trench and underthrust Pacific slab terminate in the region south of Kaikoura, as the subdution zone transitions to the Alpine fault strike-slip regime. It is difficult to establish whether any coseismic slip occurred on the megathrust from on-land observations. The rupture generated a tsunami well recorded at tide gauges along the eastern coasts and in Chatham Islands, including a 4 m crest-to-trough signal at Kaikoura where coastal uplift was about 1 m, and at multiple gauges in Wellington Harbor. Iterative modeling of teleseismic body waves and the regional water-level recordings establishes that two regions of seafloor motion produced the tsunami, including an Mw 7.6 rupture on the megathrust below Kaikoura and comparable size transpressional crustal faulting extending offshore near Cook Strait.

  4. Statistical Modeling of Fire Occurrence Using Data from the Tōhoku, Japan Earthquake and Tsunami.

    PubMed

    Anderson, Dana; Davidson, Rachel A; Himoto, Keisuke; Scawthorn, Charles

    2016-02-01

    In this article, we develop statistical models to predict the number and geographic distribution of fires caused by earthquake ground motion and tsunami inundation in Japan. Using new, uniquely large, and consistent data sets from the 2011 Tōhoku earthquake and tsunami, we fitted three types of models-generalized linear models (GLMs), generalized additive models (GAMs), and boosted regression trees (BRTs). This is the first time the latter two have been used in this application. A simple conceptual framework guided identification of candidate covariates. Models were then compared based on their out-of-sample predictive power, goodness of fit to the data, ease of implementation, and relative importance of the framework concepts. For the ground motion data set, we recommend a Poisson GAM; for the tsunami data set, a negative binomial (NB) GLM or NB GAM. The best models generate out-of-sample predictions of the total number of ignitions in the region within one or two. Prefecture-level prediction errors average approximately three. All models demonstrate predictive power far superior to four from the literature that were also tested. A nonlinear relationship is apparent between ignitions and ground motion, so for GLMs, which assume a linear response-covariate relationship, instrumental intensity was the preferred ground motion covariate because it captures part of that nonlinearity. Measures of commercial exposure were preferred over measures of residential exposure for both ground motion and tsunami ignition models. This may vary in other regions, but nevertheless highlights the value of testing alternative measures for each concept. Models with the best predictive power included two or three covariates. © 2015 Society for Risk Analysis.

  5. Modeling the 1958 Lituya Bay mega-tsunami with a PVM-IFCP GPU-based model

    NASA Astrophysics Data System (ADS)

    González-Vida, José M.; Arcas, Diego; de la Asunción, Marc; Castro, Manuel J.; Macías, Jorge; Ortega, Sergio; Sánchez-Linares, Carlos; Titov, Vasily

    2013-04-01

    In this work we present a numerical study, performed in collaboration with the NOAA Center for Tsunami Research (USA), that uses a GPU version of the PVM-IFCP landslide model for the simulation of the 1958 landslide generated tsunami of Lituya Bay. In this model, a layer composed of fluidized granular material is assumed to flow within an upper layer of an inviscid fluid (e. g. water). The model is discretized using a two dimensional PVM-IFCP [Fernández - Castro - Parés. On an Intermediate Field Capturing Riemann Solver Based on a Parabolic Viscosity Matrix for the Two-Layer Shallow Water System, J. Sci. Comput., 48 (2011):117-140] finite volume scheme implemented on GPU cards for increasing the speed-up. This model has been previously validated by using the two-dimensional physical laboratory experiments data from H. Fritz [Lituya Bay Landslide Impact Generated Mega-Tsunami 50th Anniversary. Pure Appl. Geophys., 166 (2009) pp. 153-175]. In the present work, the first step was to reconstruct the topobathymetry of the Lituya Bay before this event ocurred, this is based on USGS geological surveys data. Then, a sensitivity analysis of some model parameters has been performed in order to determine the parameters that better fit to reality, when model results are compared against available event data, as run-up areas. In this presentation, the reconstruction of the pre-tsunami scenario will be shown, a detailed simulation of the tsunami presented and several comparisons with real data (runup, wave height, etc.) shown.

  6. Physical experiments and analysis on the generation and evolution of tsunami-induced turbulent coherent structures

    NASA Astrophysics Data System (ADS)

    Kalligeris, Nikos; Lynett, Patrick

    2017-11-01

    Numerous historical accounts describe the formation of ``whirpools'' inside ports and harbors during tsunami events, causing port operation disruptions. Videos from the Japan 2011 tsunami revealed complex nearshore flow patters, resulting from the interaction of tsunami-induced currents with the man-made coastline, and the generation of large eddies (or turbulent coherent structures) in numerous ports and harbors near the earthquake epicenter. The aim of this work is to study the generation and evolution of tsunami-induced turbulent coherent structures (TCS) in a well-controlled environment using realistic scaling. A physical configuration is created in the image of a port entrance at a scale of 1:27 and a small-amplitude, long period wave creates a transient flow through the asymmetric harbor channel. A separated region forms, which coupled with the transient flow, leads to the formation of a stable monopolar TCS. The surface flow is examined through mono- and stereo-PTV techniques to extract surface velocity vectors. Surface velocity maps and vortex flow profiles are used to study the experimental TCS generation and evolution, and characterize the TCS structure. Analytical tools are used to describe the TCS growth rate and kinetic energy decay. This work was funded by the National Science Foundation NEES Research program, with Award Number 1135026.

  7. Sensitivity of the coastal tsunami simulation to the complexity of the 2011 Tohoku earthquake source model

    NASA Astrophysics Data System (ADS)

    Monnier, Angélique; Loevenbruck, Anne; Gailler, Audrey; Hébert, Hélène

    2016-04-01

    The 11 March 2011 Tohoku-Oki event, whether earthquake or tsunami, is exceptionally well documented. A wide range of onshore and offshore data has been recorded from seismic, geodetic, ocean-bottom pressure and sea level sensors. Along with these numerous observations, advance in inversion technique and computing facilities have led to many source studies. Rupture parameters inversion such as slip distribution and rupture history permit to estimate the complex coseismic seafloor deformation. From the numerous published seismic source studies, the most relevant coseismic source models are tested. The comparison of the predicted signals generated using both static and cinematic ruptures to the offshore and coastal measurements help determine which source model should be used to obtain the more consistent coastal tsunami simulations. This work is funded by the TANDEM project, reference ANR-11-RSNR-0023-01 of the French Programme Investissements d'Avenir (PIA 2014-2018).

  8. Pyroclastic Flow Generated Tsunami Waves Detected by CALIPSO Borehole Strainmeters at Soufriere Hills, Montserrat During Massive Dome Collapse: Numerical Simulations and Observations

    NASA Astrophysics Data System (ADS)

    van Boskirk, E. J.; Voight, B.; Watts, P.; Widiwijayanti, C.; Mattioli, G. S.; Elsworth, D.; Hidayat, D.; Linde, A.; Malin, P.; Neuberg, J.; Sacks, S.; Shalev, E.; Sparks, R. J.; Young, S. R.

    2004-12-01

    The July 12-13, 2003 eruption (dome collapse plus explosions) of Soufriere Hills Volcano in Montserrat, WI, is the largest historical lava dome collapse with ˜120 million cubic meters of the dome lost. Pyroclastic flows entered the sea at 18:00 AST 12 July at the Tar River Valley (TRV) and continued until the early hours of 13 July. Low-amplitude tsunamis were reported at Antigua and Guadaloupe soon after the dome collapse. At the time of eruption, four CALIPSO borehole-monitoring stations were in the process of being installed, and three very-broad-band Sacks-Evertson dilatometers were operational and recorded the event at 50 sps. The strongest strain signals were recorded at the Trants site, 5 km north of the TRV entry zone, suggesting tsunami waves >1 m high. Debris strandlines closer to TRV recorded runup heights as much as 8 m. We test the hypothesis that the strain signal is related to tsunami waves generated by successive pyroclastic flows induced during the dome collapse. Tsunami simulation models have been generated using GEOWAVE, which uses simple physics to recreate waves generated by idealized pyroclastic flows entering the sea at TRV. Each simulation run contains surface wave amplitude gauges located in key positions to the three borehole sites. These simulated wave amplitudes and periods are compared quantitatively with the data recorded by the dilatometers and with field observations of wave runup, to elucidate the dynamics of pyroclastic flow tsunami genesis and its propagation in shallow ocean water.

  9. Tsunami Impact Computed from Offshore Modeling and Coastal Amplification Laws: Insights from the 2004 Indian Ocean Tsunami

    NASA Astrophysics Data System (ADS)

    Hébert, H.; Schindelé, F.

    2015-12-01

    The 2004 Indian Ocean tsunami gave the opportunity to gather unprecedented tsunami observation databases for various coastlines. We present here an analysis of such databases gathered for 3 coastlines, among the most impacted in 2004 in the intermediate- and far field: Thailand-Myanmar, SE India-Sri Lanka, and SE Madagascar. Non-linear shallow water tsunami modeling performed on a single 4' coarse bathymetric grid is compared to these observations, in order to check to which extent a simple approach based on the usual energy conservation laws (either Green's or Synolakis laws) can explain the data. The idea is to fit tsunami data with numerical modeling carried out without any refined coastal bathymetry/topography. To this end several parameters are discussed, namely the bathymetric depth to which model results must be extrapolated (using the Green's law), or the mean bathymetric slope to consider near the studied coast (when using the Synolakis law). Using extrapolation depths from 1 to 10 m generally allows a good fit; however, a 0.1 m is required for some others, especially in the far field (Madagascar) possibly due to enhanced numerical dispersion. Such a method also allows describing the tsunami impact variability along a given coastline. Then, using a series of scenarios, we propose a preliminary statistical assessment of tsunami impact for a given earthquake magnitude along the Indonesian subduction. Conversely, the sources mostly contributing to a specific hazard can also be mapped onto the sources, providing a first order definition of which sources are threatening the 3 studied coastlines.

  10. Anatomy of Historical Tsunamis: Lessons Learned for Tsunami Warning

    NASA Astrophysics Data System (ADS)

    Igarashi, Y.; Kong, L.; Yamamoto, M.; McCreery, C. S.

    2011-11-01

    Tsunamis are high-impact disasters that can cause death and destruction locally within a few minutes of their occurrence and across oceans hours, even up to a day, afterward. Efforts to establish tsunami warning systems to protect life and property began in the Pacific after the 1946 Aleutian Islands tsunami caused casualties in Hawaii. Seismic and sea level data were used by a central control center to evaluate tsunamigenic potential and then issue alerts and warnings. The ensuing events of 1952, 1957, and 1960 tested the new system, which continued to expand and evolve from a United States system to an international system in 1965. The Tsunami Warning System in the Pacific (ITSU) steadily improved through the decades as more stations became available in real and near-real time through better communications technology and greater bandwidth. New analysis techniques, coupled with more data of higher quality, resulted in better detection, greater solution accuracy, and more reliable warnings, but limitations still exist in constraining the source and in accurately predicting propagation of the wave from source to shore. Tsunami event data collected over the last two decades through international tsunami science surveys have led to more realistic models for source generation and inundation, and within the warning centers, real-time tsunami wave forecasting will become a reality in the near future. The tsunami warning system is an international cooperative effort amongst countries supported by global and national monitoring networks and dedicated tsunami warning centers; the research community has contributed to the system by advancing and improving its analysis tools. Lessons learned from the earliest tsunamis provided the backbone for the present system, but despite 45 years of experience, the 2004 Indian Ocean tsunami reminded us that tsunamis strike and kill everywhere, not just in the Pacific. Today, a global intergovernmental tsunami warning system is coordinated

  11. Modeling the 2004Indian Ocean Tsunami for Introductory Physics Students

    NASA Astrophysics Data System (ADS)

    DiLisi, Gregory A.; Rarick, Richard A.

    2006-12-01

    In this paper we develop materials to address student interest in the Indian Ocean tsunami of December 2004. We discuss the physical characteristics of tsunamis and some of the specific data regarding the 2004 event. Finally, we create an easy-to-make tsunami tank to run simulations in the classroom. The simulations exhibit three dramatic signatures of tsunamis, namely, as a tsunami moves into shallow water its amplitude increases, its wavelength and speed decrease, and its leading edge becomes increasingly steep as if to "break" or "crash." Using our tsunami tank, these realistic features were easy to observe in the classroom and evoked an enthusiastic response from our students.

  12. How much does geometry of seismic sources matter in tsunami modeling? A sensitivity analysis for the Calabrian subduction interface

    NASA Astrophysics Data System (ADS)

    Tonini, R.; Maesano, F. E.; Tiberti, M. M.; Romano, F.; Scala, A.; Lorito, S.; Volpe, M.; Basili, R.

    2017-12-01

    The geometry of seismogenic sources could be one of the most important factors concurring to control the generation and the propagation of earthquake-generated tsunamis and their effects on the coasts. Since the majority of potentially tsunamigenic earthquakes occur offshore, the corresponding faults are generally poorly constrained and, consequently, their geometry is often oversimplified as a planar fault. The rupture area of mega-thrust earthquakes in subduction zones, where most of the greatest tsunamis have occurred, extends for tens to hundreds of kilometers both down dip and along strike, and generally deviates from the planar geometry. Therefore, the larger the earthquake size is, the weaker the planar fault assumption become. In this work, we present a sensitivity analysis aimed to explore the effects on modeled tsunamis generated by seismic sources with different degrees of geometric complexities. We focused on the Calabrian subduction zone, located in the Mediterranean Sea, which is characterized by the convergence between the African and European plates, with rates of up to 5 mm/yr. This subduction zone has been considered to have generated some past large earthquakes and tsunamis, despite it shows only in-slab significant seismic activity below 40 km depth and no relevant seismicity in the shallower portion of the interface. Our analysis is performed by defining and modeling an exhaustive set of tsunami scenarios located in the Calabrian subduction and using different models of the subduction interface with increasing geometrical complexity, from a planar surface to a highly detailed 3D surface. The latter was obtained from the interpretation of a dense network of seismic reflection profiles coupled with the analysis of the seismicity distribution. The more relevant effects due to the inclusion of 3D complexities in the seismic source geometry are finally highlighted in terms of the resulting tsunami impact.

  13. Analysis of the tsunami generated by the MW 7.8 1906 San Francisco earthquake

    USGS Publications Warehouse

    Geist, E.L.; Zoback, M.L.

    1999-01-01

    We examine possible sources of a small tsunami produced by the 1906 San Francisco earthquake, recorded at a single tide gauge station situated at the opening to San Francisco Bay. Coseismic vertical displacement fields were calculated using elastic dislocation theory for geodetically constrained horizontal slip along a variety of offshore fault geometries. Propagation of the ensuing tsunami was calculated using a shallow-water hydrodynamic model that takes into account the effects of bottom friction. The observed amplitude and negative pulse of the first arrival are shown to be inconsistent with small vertical displacements (~4-6 cm) arising from pure horizontal slip along a continuous right bend in the San Andreas fault offshore. The primary source region of the tsunami was most likely a recently recognized 3 km right step in the San Andreas fault that is also the probable epicentral region for the 1906 earthquake. Tsunami models that include the 3 km right step with pure horizontal slip match the arrival time of the tsunami, but underestimate the amplitude of the negative first-arrival pulse. Both the amplitude and time of the first arrival are adequately matched by using a rupture geometry similar to that defined for the 1995 MW (moment magnitude) 6.9 Kobe earthquake: i.e., fault segments dipping toward each other within the stepover region (83??dip, intersecting at 10 km depth) and a small component of slip in the dip direction (rake=-172??). Analysis of the tsunami provides confirming evidence that the 1906 San Francisco earthquake initiated at a right step in a right-lateral fault and propagated bilaterally, suggesting a rupture initiation mechanism similar to that for the 1995 Kobe earthquake.

  14. Standards and Guidelines for Numerical Models for Tsunami Hazard Mitigation

    NASA Astrophysics Data System (ADS)

    Titov, V.; Gonzalez, F.; Kanoglu, U.; Yalciner, A.; Synolakis, C. E.

    2006-12-01

    An increased number of nations around the workd need to develop tsunami mitigation plans which invariably involve inundation maps for warning guidance and evacuation planning. There is the risk that inundation maps may be produced with older or untested methodology, as there are currently no standards for modeling tools. In the aftermath of the 2004 megatsunami, some models were used to model inundation for Cascadia events with results much larger than sediment records and existing state-of-the-art studies suggest leading to confusion among emergency management. Incorrectly assessing tsunami impact is hazardous, as recent events in 2006 in Tonga, Kythira, Greece and Central Java have suggested (Synolakis and Bernard, 2006). To calculate tsunami currents, forces and runup on coastal structures, and inundation of coastlines one must calculate the evolution of the tsunami wave from the deep ocean to its target site, numerically. No matter what the numerical model, validation (the process of ensuring that the model solves the parent equations of motion accurately) and verification (the process of ensuring that the model used represents geophysical reality appropriately) both are an essential. Validation ensures that the model performs well in a wide range of circumstances and is accomplished through comparison with analytical solutions. Verification ensures that the computational code performs well over a range of geophysical problems. A few analytic solutions have been validated themselves with laboratory data. Even fewer existing numerical models have been both validated with the analytical solutions and verified with both laboratory measurements and field measurements, thus establishing a gold standard for numerical codes for inundation mapping. While there is in principle no absolute certainty that a numerical code that has performed well in all the benchmark tests will also produce correct inundation predictions with any given source motions, validated codes

  15. Landslide tsunami hazard in New South Wales, Australia: novel observations from 3D modelling

    NASA Astrophysics Data System (ADS)

    Power, Hannah; Clarke, Samantha; Hubble, Tom

    2015-04-01

    This paper examines the potential of tsunami inundation generated from two case study sites of submarine mass failures on the New South Wales coast of Australia. Two submarine mass failure events are investigated: the Bulli Slide and the Shovel Slide. Both slides are located approximately 65 km southeast of Sydney and 60 km east of the township of Wollongong. The Bulli Slide (~20 km3) and the Shovel Slide (7.97 km3) correspond to the two largest identified erosional surface submarine landslides scars of the NSW continental margin (Glenn et al. 2008; Clarke 2014) and represent examples of large to very large submarine landslide scars. The Shovel Slide is a moderately thick (80-165 m), moderately wide to wide (4.4 km) slide, and is located in 880 m water depth; and the Bulli Slide is an extremely thick (200-425 m), very wide (8.9 km) slide, and is located in 1500 m water depth. Previous work on the east Australian margin (Clarke et al., 2014) and elsewhere (Harbitz et al., 2013) suggests that submarine landslides similar to the Bulli Slide or the Shovel Slide are volumetrically large enough and occur at shallow enough water depths (400-2500 m) to generate substantial tsunamis that could cause widespread damage on the east Australian coast and threaten coastal communities (Burbidge et al. 2008; Clarke 2014; Talukder and Volker 2014). Currently, the tsunamogenic potential of these two slides has only been investigated using 2D modelling (Clarke 2014) and to date it has been difficult to establish the onshore tsunami surge characteristics for the submarine landslides with certainty. To address this knowledge gap, the forecast inundation as a result of these two mass failure events was investigated using a three-dimensional model (ANUGA) that predicts water flow resulting from natural hazard events such as tsunami (Nielsen et al., 2005). The ANUGA model solves the two-dimensional shallow water wave equations and accurately models the process of wetting and drying thus

  16. Modeling the 2004 Indian Ocean Tsunami for Introductory Physics Students

    ERIC Educational Resources Information Center

    DiLisi, Gregory A.; Rarick, Richard A.

    2006-01-01

    In this paper we develop materials to address student interest in the Indian Ocean tsunami of December 2004. We discuss the physical characteristics of tsunamis and some of the specific data regarding the 2004 event. Finally, we create an easy-to-make tsunami tank to run simulations in the classroom. The simulations exhibit three dramatic…

  17. Modeling influence of tide stages on forecasts of the 2010 Chilean tsunami

    NASA Astrophysics Data System (ADS)

    Uslu, B. U.; Chamberlin, C.; Walsh, D.; Eble, M. C.

    2010-12-01

    The impact of the 2010 Chilean tsunami is studied using the NOAA high-resolution tsunami forecast model augmented to include modeled tide heights in addition to deep-water tsunami propagation as boundary-condition input. The Chilean tsunami was observed at the Los Angeles tide station at mean low water, Hilo at low, Pago Pago at mid tide and Wake Island near high tide. Because the tsunami arrived at coastal communities at a representative variety of tide stages, 2010 Chile tsunami provides opportunity to study the tsunami impacts at different tide levels to different communities. The current forecast models are computed with a constant tidal stage, and this study evaluates techniques for adding an additional varying predicted tidal component in a forecasting context. Computed wave amplitudes, wave currents and flooding are compared at locations around the Pacific, and the difference in tsunami impact due to tidal stage is studied. This study focuses on how tsunami impacts vary with different tide levels, and helps us understand how the inclusion of tidal components can improve real-time forecast accuracy.

  18. Modeling of Grain Size Distribution of Tsunami Sand Deposits in V-shaped Valley of Numanohama During the 2011 Tohoku Tsunami

    NASA Astrophysics Data System (ADS)

    Gusman, A. R.; Satake, K.; Goto, T.; Takahashi, T.

    2016-12-01

    Estimating tsunami amplitude from tsunami sand deposit has been a challenge. The grain size distribution of tsunami sand deposit may have correlation with tsunami inundation process, and further with its source characteristics. In order to test this hypothesis, we need a tsunami sediment transport model that can accurately estimate grain size distribution of tsunami deposit. Here, we built and validate a tsunami sediment transport model that can simulate grain size distribution. Our numerical model has three layers which are suspended load layer, active bed layer, and parent bed layer. The two bed layers contain information about the grain size distribution. This numerical model can handle a wide range of grain sizes from 0.063 (4 ϕ) to 5.657 mm (-2.5 ϕ). We apply the numerical model to simulate the sedimentation process during the 2011 Tohoku earthquake in Numanohama, Iwate prefecture, Japan. The grain size distributions at 15 sample points along a 900 m transect from the beach are used to validate the tsunami sediment transport model. The tsunami deposits are dominated by coarse sand with diameter of 0.5 - 1 mm and their thickness are up to 25 cm. Our tsunami model can well reproduce the observed tsunami run-ups that are ranged from 16 to 34 m along the steep valley in Numanohama. The shapes of the simulated grain size distributions at many sample points located within 300 m from the shoreline are similar to the observations. The differences between observed and simulated peak of grain size distributions are less than 1 ϕ. Our result also shows that the simulated sand thickness distribution along the transect is consistent with the observation.

  19. Model validation and error estimation of tsunami runup using high resolution data in Sadeng Port, Gunungkidul, Yogyakarta

    NASA Astrophysics Data System (ADS)

    Basith, Abdul; Prakoso, Yudhono; Kongko, Widjo

    2017-07-01

    A tsunami model using high resolution geometric data is indispensable in efforts to tsunami mitigation, especially in tsunami prone areas. It is one of the factors that affect the accuracy results of numerical modeling of tsunami. Sadeng Port is a new infrastructure in the Southern Coast of Java which could potentially hit by massive tsunami from seismic gap. This paper discusses validation and error estimation of tsunami model created using high resolution geometric data in Sadeng Port. Tsunami model validation uses the height wave of Tsunami Pangandaran 2006 recorded by Tide Gauge of Sadeng. Tsunami model will be used to accommodate the tsunami numerical modeling involves the parameters of earthquake-tsunami which is derived from the seismic gap. The validation results using t-test (student) shows that the height of the tsunami modeling results and observation in Tide Gauge of Sadeng are considered statistically equal at 95% confidence level and the value of the RMSE and NRMSE are 0.428 m and 22.12%, while the differences of tsunami wave travel time is 12 minutes.

  20. Using Multi-Scenario Tsunami Modelling Results combined with Probabilistic Analyses to provide Hazard Information for the South-WestCoast of Indonesia

    NASA Astrophysics Data System (ADS)

    Zosseder, K.; Post, J.; Steinmetz, T.; Wegscheider, S.; Strunz, G.

    2009-04-01

    Indonesia is located at one of the most active geological subduction zones in the world. Following the most recent seaquakes and their subsequent tsunamis in December 2004 and July 2006 it is expected that also in the near future tsunamis are likely to occur due to increased tectonic tensions leading to abrupt vertical seafloor alterations after a century of relative tectonic silence. To face this devastating threat tsunami hazard maps are very important as base for evacuation planning and mitigation strategies. In terms of a tsunami impact the hazard assessment is mostly covered by numerical modelling because the model results normally offer the most precise database for a hazard analysis as they include spatially distributed data and their influence to the hydraulic dynamics. Generally a model result gives a probability for the intensity distribution of a tsunami at the coast (or run up) and the spatial distribution of the maximum inundation area depending on the location and magnitude of the tsunami source used. The boundary condition of the source used for the model is mostly chosen by a worst case approach. Hence the location and magnitude which are likely to occur and which are assumed to generate the worst impact are used to predict the impact at a specific area. But for a tsunami hazard assessment covering a large coastal area, as it is demanded in the GITEWS (German Indonesian Tsunami Early Warning System) project in which the present work is embedded, this approach is not practicable because a lot of tsunami sources can cause an impact at the coast and must be considered. Thus a multi-scenario tsunami model approach is developed to provide a reliable hazard assessment covering large areas. For the Indonesian Early Warning System many tsunami scenarios were modelled by the Alfred Wegener Institute (AWI) at different probable tsunami sources and with different magnitudes along the Sunda Trench. Every modelled scenario delivers the spatial distribution of

  1. Using landscape analysis to assess and model tsunami damage in Aceh province, Sumatra

    Treesearch

    Louis R. Iverson; Anantha Prasad

    2007-01-01

    The nearly unprecedented loss of life resulting from the earthquake and tsunami of December 26,2004, was greatest in the province of Aceh, Sumatra (Indonesia). We evaluated tsunami damage and built empirical vulnerability models of damage/no damage based on elevation, distance from shore, vegetation, and exposure. We found that highly predictive models are possible and...

  2. The role of deposits in tsunami risk assessment

    USGS Publications Warehouse

    Jaffe, B.

    2008-01-01

    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.

  3. Introduction to "Global Tsunami Science: Past and Future, Volume II"

    NASA Astrophysics Data System (ADS)

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2017-08-01

    Twenty-two papers on the study of tsunamis are included in Volume II of the PAGEOPH topical issue "Global Tsunami Science: Past and Future". Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 (Eds., E. L. Geist, H. M. Fritz, A. B. Rabinovich, and Y. Tanioka). Three papers in Volume II focus on details of the 2011 and 2016 tsunami-generating earthquakes offshore of Tohoku, Japan. The next six papers describe important case studies and observations of recent and historical events. Four papers related to tsunami hazard assessment are followed by three papers on tsunami hydrodynamics and numerical modelling. Three papers discuss problems of tsunami warning and real-time forecasting. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: volcanic explosions, landslides, and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  4. The UBO-TSUFD tsunami inundation model: validation and application to a tsunami case study focused on the city of Catania, Italy

    NASA Astrophysics Data System (ADS)

    Tinti, S.; Tonini, R.

    2013-07-01

    Nowadays numerical models are a powerful tool in tsunami research since they can be used (i) to reconstruct modern and historical events, (ii) to cast new light on tsunami sources by inverting tsunami data and observations, (iii) to build scenarios in the frame of tsunami mitigation plans, and (iv) to produce forecasts of tsunami impact and inundation in systems of early warning. In parallel with the general recognition of the importance of numerical tsunami simulations, the demand has grown for reliable tsunami codes, validated through tests agreed upon by the tsunami community. This paper presents the tsunami code UBO-TSUFD that has been developed at the University of Bologna, Italy, and that solves the non-linear shallow water (NSW) equations in a Cartesian frame, with inclusion of bottom friction and exclusion of the Coriolis force, by means of a leapfrog (LF) finite-difference scheme on a staggered grid and that accounts for moving boundaries to compute sea inundation and withdrawal at the coast. Results of UBO-TSUFD applied to four classical benchmark problems are shown: two benchmarks are based on analytical solutions, one on a plane wave propagating on a flat channel with a constant slope beach; and one on a laboratory experiment. The code is proven to perform very satisfactorily since it reproduces quite well the benchmark theoretical and experimental data. Further, the code is applied to a realistic tsunami case: a scenario of a tsunami threatening the coasts of eastern Sicily, Italy, is defined and discussed based on the historical tsunami of 11 January 1693, i.e. one of the most severe events in the Italian history.

  5. Tsunami modelling with adaptively refined finite volume methods

    USGS Publications Warehouse

    LeVeque, R.J.; George, D.L.; Berger, M.J.

    2011-01-01

    Numerical modelling of transoceanic tsunami propagation, together with the detailed modelling of inundation of small-scale coastal regions, poses a number of algorithmic challenges. The depth-averaged shallow water equations can be used to reduce this to a time-dependent problem in two space dimensions, but even so it is crucial to use adaptive mesh refinement in order to efficiently handle the vast differences in spatial scales. This must be done in a 'wellbalanced' manner that accurately captures very small perturbations to the steady state of the ocean at rest. Inundation can be modelled by allowing cells to dynamically change from dry to wet, but this must also be done carefully near refinement boundaries. We discuss these issues in the context of Riemann-solver-based finite volume methods for tsunami modelling. Several examples are presented using the GeoClaw software, and sample codes are available to accompany the paper. The techniques discussed also apply to a variety of other geophysical flows. ?? 2011 Cambridge University Press.

  6. Tsunami hazard assessment in El Salvador, Central America, from seismic sources through flooding numerical models

    NASA Astrophysics Data System (ADS)

    Álvarez-Gómez, J. A.; Aniel-Quiroga, Í.; Gutiérrez-Gutiérrez, O. Q.; Larreynaga, J.; González, M.; Castro, M.; Gavidia, F.; Aguirre-Ayerbe, I.; González-Riancho, P.; Carreño, E.

    2013-05-01

    El Salvador is the smallest and most densely populated country in Central America; its coast has approximately a length of 320 km, 29 municipalities and more than 700 000 inhabitants. In El Salvador there have been 15 recorded tsunamis between 1859 and 2012, 3 of them causing damages and hundreds of victims. The hazard assessment is commonly based on propagation numerical models for earthquake-generated tsunamis and can be approached from both Probabilistic and Deterministic Methods. A deterministic approximation has been applied in this study as it provides essential information for coastal planning and management. The objective of the research was twofold, on the one hand the characterization of the threat over the entire coast of El Salvador, and on the other the computation of flooding maps for the three main localities of the Salvadorian coast. For the latter we developed high resolution flooding models. For the former, due to the extension of the coastal area, we computed maximum elevation maps and from the elevation in the near-shore we computed an estimation of the run-up and the flooded area using empirical relations. We have considered local sources located in the Middle America Trench, characterized seismotectonically, and distant sources in the rest of Pacific basin, using historical and recent earthquakes and tsunamis. We used a hybrid finite differences - finite volumes numerical model in this work, based on the Linear and Non-linear Shallow Water Equations, to simulate a total of 24 earthquake generated tsunami scenarios. In the western Salvadorian coast, run-up values higher than 5 m are common, while in the eastern area, approximately from La Libertad to the Gulf of Fonseca, the run-up values are lower. The more exposed areas to flooding are the lowlands in the Lempa River delta and the Barra de Santiago Western Plains. The results of the empirical approximation used for the whole country are similar to the results obtained with the high resolution

  7. Tsunami hazard assessment in El Salvador, Central America, from seismic sources through flooding numerical models.

    NASA Astrophysics Data System (ADS)

    Álvarez-Gómez, J. A.; Aniel-Quiroga, Í.; Gutiérrez-Gutiérrez, O. Q.; Larreynaga, J.; González, M.; Castro, M.; Gavidia, F.; Aguirre-Ayerbe, I.; González-Riancho, P.; Carreño, E.

    2013-11-01

    El Salvador is the smallest and most densely populated country in Central America; its coast has an approximate length of 320 km, 29 municipalities and more than 700 000 inhabitants. In El Salvador there were 15 recorded tsunamis between 1859 and 2012, 3 of them causing damages and resulting in hundreds of victims. Hazard assessment is commonly based on propagation numerical models for earthquake-generated tsunamis and can be approached through both probabilistic and deterministic methods. A deterministic approximation has been applied in this study as it provides essential information for coastal planning and management. The objective of the research was twofold: on the one hand the characterization of the threat over the entire coast of El Salvador, and on the other the computation of flooding maps for the three main localities of the Salvadorian coast. For the latter we developed high-resolution flooding models. For the former, due to the extension of the coastal area, we computed maximum elevation maps, and from the elevation in the near shore we computed an estimation of the run-up and the flooded area using empirical relations. We have considered local sources located in the Middle America Trench, characterized seismotectonically, and distant sources in the rest of Pacific Basin, using historical and recent earthquakes and tsunamis. We used a hybrid finite differences-finite volumes numerical model in this work, based on the linear and non-linear shallow water equations, to simulate a total of 24 earthquake-generated tsunami scenarios. Our results show that at the western Salvadorian coast, run-up values higher than 5 m are common, while in the eastern area, approximately from La Libertad to the Gulf of Fonseca, the run-up values are lower. The more exposed areas to flooding are the lowlands in the Lempa River delta and the Barra de Santiago Western Plains. The results of the empirical approximation used for the whole country are similar to the results

  8. Introduction to "Global Tsunami Science: Past and Future, Volume III"

    NASA Astrophysics Data System (ADS)

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2018-04-01

    Twenty papers on the study of tsunamis are included in Volume III of the PAGEOPH topical issue "Global Tsunami Science: Past and Future". Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 and Volume II as PAGEOPH, vol. 174, No. 8, 2017. Two papers in Volume III focus on specific details of the 2009 Samoa and the 1923 northern Kamchatka tsunamis; they are followed by three papers related to tsunami hazard assessment for three different regions of the world oceans: South Africa, Pacific coast of Mexico and the northwestern part of the Indian Ocean. The next six papers are on various aspects of tsunami hydrodynamics and numerical modelling, including tsunami edge waves, resonant behaviour of compressible water layer during tsunamigenic earthquakes, dispersive properties of seismic and volcanically generated tsunami waves, tsunami runup on a vertical wall and influence of earthquake rupture velocity on maximum tsunami runup. Four papers discuss problems of tsunami warning and real-time forecasting for Central America, the Mediterranean coast of France, the coast of Peru, and some general problems regarding the optimum use of the DART buoy network for effective real-time tsunami warning in the Pacific Ocean. Two papers describe historical and paleotsunami studies in the Russian Far East. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: asteroid airburst and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  9. Destructive tsunami-like wave generated by surf beat over a coral reef during Typhoon Haiyan.

    PubMed

    Roeber, Volker; Bricker, Jeremy D

    2015-08-06

    Storm surges cause coastal inundation due to setup of the water surface resulting from atmospheric pressure, surface winds and breaking waves. Here we show that during Typhoon Haiyan, the setup generated by breaking waves near the fringing-reef-protected town of Hernani, the Philippines, oscillated with the incidence of large and small wave groups, and steepened into a tsunami-like wave that caused extensive damage and casualties. Though fringing reefs usually protect coastal communities from moderate storms, they can exacerbate flooding during strong events with energetic waves. Typical for reef-type bathymetries, a very short wave-breaking zone over the steep reef face facilitates the freeing of infragravity-period fluctuations (surf beat) with little energy loss. Since coastal flood planning relies on phase-averaged wave modelling, infragravity surges are not being accounted for. This highlights the necessity for a policy change and the adoption of phase-resolving wave models for hazard assessment in regions with fringing reefs.

  10. Destructive tsunami-like wave generated by surf beat over a coral reef during Typhoon Haiyan

    PubMed Central

    Roeber, Volker; Bricker, Jeremy D.

    2015-01-01

    Storm surges cause coastal inundation due to setup of the water surface resulting from atmospheric pressure, surface winds and breaking waves. Here we show that during Typhoon Haiyan, the setup generated by breaking waves near the fringing-reef-protected town of Hernani, the Philippines, oscillated with the incidence of large and small wave groups, and steepened into a tsunami-like wave that caused extensive damage and casualties. Though fringing reefs usually protect coastal communities from moderate storms, they can exacerbate flooding during strong events with energetic waves. Typical for reef-type bathymetries, a very short wave-breaking zone over the steep reef face facilitates the freeing of infragravity-period fluctuations (surf beat) with little energy loss. Since coastal flood planning relies on phase-averaged wave modelling, infragravity surges are not being accounted for. This highlights the necessity for a policy change and the adoption of phase-resolving wave models for hazard assessment in regions with fringing reefs. PMID:26245839

  11. Comparison of the seafloor displacement from uniform and non-uniform slip models on tsunami simulation of the 2011 Tohoku-Oki earthquake

    NASA Astrophysics Data System (ADS)

    Ulutas, Ergin

    2013-01-01

    The numerical simulations of recent tsunami caused by 11 March 2011 off-shore Pacific coast of Tohoku-Oki earthquake (Mw 9.0) using diverse co-seismic source models have been performed. Co-seismic source models proposed by various observational agencies and scholars are further used to elucidate the effects of uniform and non-uniform slip models on tsunami generation and propagation stages. Non-linear shallow water equations are solved with a finite difference scheme, using a computational grid with different cell sizes over GEBCO30 bathymetry data. Overall results obtained and reported by various tsunami simulation models are compared together with the available real-time kinematic global positioning system (RTK-GPS) buoys, cabled deep ocean-bottom pressure gauges (OBPG), and Deep-ocean Assessment and Reporting of Tsunami (DART) buoys. The purpose of this study is to provide a brief overview of major differences between point-source and finite-fault methodologies on generation and simulation of tsunamis. Tests of the assumptions of uniform and non-uniform slip models designate that the average uniform slip models may be used for the tsunami simulations off-shore, and far from the source region. Nevertheless, the heterogeneities of the slip distribution within the fault plane are substantial for the wave amplitude in the near field which should be investigated further.

  12. A 2D-3D strategy for resolving tsunami-generated debris flow in urban environments

    NASA Astrophysics Data System (ADS)

    Birjukovs Canelas, Ricardo; Conde, Daniel; Garcia-Feal, Orlando; João Telhado, Maria; Ferreira, Rui M. L.

    2017-04-01

    The incorporation of solids, either sediment from the natural environment or remains from buildings or infrastructures is a relevant feature of tsunami run-up in urban environments, greatly increasing the destructive potential of tsunami propagation. Two-dimensional (2D) models have been used to assess the propagation of the bore, even in dense urban fronts. Computational advances are introduced in this work, namely a fully lagrangian, 3D description of the fluid-solid flow, coupled with a high performance meshless implementation capable of dealing with large domains and fine discretizations. A Smoothed Particle Hydrodynamics (SPH) Navier-Stokes discretization and a Distributed Contact Discrete Element Method (DCDEM) description of solid-solid interactions provide a state-of the-art fluid-solid flow description. Together with support for arbitrary geometries, centimetre scale resolution simulations of a city section in Lisbon downtown are presented. 2D results are used as boundary conditions for the 3D model, characterizing the incoming wave as it approaches the coast. It is shown that the incoming bore is able to mobilize and incorporate standing vehicles and other urban hardware. Such fully featured simulation provides explicit description of the interactions among fluid, floating debris (vehicles and urban furniture), the buildings and the pavement. The proposed model presents both an innovative research tool for the study of these flows and a powerful and robust approach to study, design and test mitigation solutions at the local scale. At the same time, due to the high time and space resolution of these methodologies, new questions are raised: scenario-building and initial configurations play a crucial role but they do not univocally determine the final configuration of the simulation, as the solution of the Navier-Stokes equations for high Reynolds numbers possesses a high number of degrees of freedom. This calls for conducting the simulations in a

  13. A Probabilistic Tsunami Hazard Study of the Auckland Region, Part II: Inundation Modelling and Hazard Assessment

    NASA Astrophysics Data System (ADS)

    Lane, E. M.; Gillibrand, P. A.; Wang, X.; Power, W.

    2013-09-01

    Regional source tsunamis pose a potentially devastating hazard to communities and infrastructure on the New Zealand coast. But major events are very uncommon. This dichotomy of infrequent but potentially devastating hazards makes realistic assessment of the risk challenging. Here, we describe a method to determine a probabilistic assessment of the tsunami hazard by regional source tsunamis with an "Average Recurrence Interval" of 2,500-years. The method is applied to the east Auckland region of New Zealand. From an assessment of potential regional tsunamigenic events over 100,000 years, the inundation of the Auckland region from the worst 100 events is modelled using a hydrodynamic model and probabilistic inundation depths on a 2,500-year time scale were determined. Tidal effects on the potential inundation were included by coupling the predicted wave heights with the probability density function of tidal heights at the inundation site. Results show that the more exposed northern section of the east coast and outer islands in the Hauraki Gulf face the greatest hazard from regional tsunamis in the Auckland region. Incorporating tidal effects into predictions of inundation reduced the predicted hazard compared to modelling all the tsunamis arriving at high tide giving a more accurate hazard assessment on the specified time scale. This study presents the first probabilistic analysis of dynamic modelling of tsunami inundation for the New Zealand coast and as such provides the most comprehensive assessment of tsunami inundation of the Auckland region from regional source tsunamis available to date.

  14. Lessons from the Tōhoku tsunami: A model for island avifauna conservation prioritization.

    PubMed

    Reynolds, Michelle H; Berkowitz, Paul; Klavitter, John L; Courtot, Karen N

    2017-08-01

    Earthquake-generated tsunamis threaten coastal areas and low-lying islands with sudden flooding. Although human hazards and infrastructure damage have been well documented for tsunamis in recent decades, the effects on wildlife communities rarely have been quantified. We describe a tsunami that hit the world's largest remaining tropical seabird rookery and estimate the effects of sudden flooding on 23 bird species nesting on Pacific islands more than 3,800 km from the epicenter. We used global positioning systems, tide gauge data, and satellite imagery to quantify characteristics of the Tōhoku earthquake-generated tsunami (11 March 2011) and its inundation extent across four Hawaiian Islands. We estimated short-term effects of sudden flooding to bird communities using spatially explicit data from Midway Atoll and Laysan Island, Hawai'i. We describe variation in species vulnerability based on breeding phenology, nesting habitat, and life history traits. The tsunami inundated 21%-100% of each island's area at Midway Atoll and Laysan Island. Procellariformes (albatrosses and petrels) chick and egg losses exceeded 258,500 at Midway Atoll while albatross chick losses at Laysan Island exceeded 21,400. The tsunami struck at night and during the peak of nesting for 14 colonial seabird species. Strongly philopatric Procellariformes were vulnerable to the tsunami. Nonmigratory, endemic, endangered Laysan Teal ( Anas laysanensis ) were sensitive to ecosystem effects such as habitat changes and carcass-initiated epizootics of avian botulism, and its populations declined approximately 40% on both atolls post-tsunami. Catastrophic flooding of Pacific islands occurs periodically not only from tsunamis, but also from storm surge and rainfall; with sea-level rise, the frequency of sudden flooding events will likely increase. As invasive predators occupy habitat on higher elevation Hawaiian Islands and globally important avian populations are concentrated on low-lying islands

  15. Lessons from the Tōhoku tsunami: A model for island avifauna conservation prioritization

    USGS Publications Warehouse

    Reynolds, Michelle H.; Berkowitz, Paul; Klavitter, John; Courtot, Karen

    2017-01-01

    Earthquake-generated tsunamis threaten coastal areas and low-lying islands with sudden flooding. Although human hazards and infrastructure damage have been well documented for tsunamis in recent decades, the effects on wildlife communities rarely have been quantified. We describe a tsunami that hit the world's largest remaining tropical seabird rookery and estimate the effects of sudden flooding on 23 bird species nesting on Pacific islands more than 3,800 km from the epicenter. We used global positioning systems, tide gauge data, and satellite imagery to quantify characteristics of the Tōhoku earthquake-generated tsunami (11 March 2011) and its inundation extent across four Hawaiian Islands. We estimated short-term effects of sudden flooding to bird communities using spatially explicit data from Midway Atoll and Laysan Island, Hawai'i. We describe variation in species vulnerability based on breeding phenology, nesting habitat, and life history traits. The tsunami inundated 21%–100% of each island's area at Midway Atoll and Laysan Island. Procellariformes (albatrosses and petrels) chick and egg losses exceeded 258,500 at Midway Atoll while albatross chick losses at Laysan Island exceeded 21,400. The tsunami struck at night and during the peak of nesting for 14 colonial seabird species. Strongly philopatric Procellariformes were vulnerable to the tsunami. Nonmigratory, endemic, endangered Laysan Teal (Anas laysanensis) were sensitive to ecosystem effects such as habitat changes and carcass-initiated epizootics of avian botulism, and its populations declined approximately 40% on both atolls post-tsunami. Catastrophic flooding of Pacific islands occurs periodically not only from tsunamis, but also from storm surge and rainfall; with sea-level rise, the frequency of sudden flooding events will likely increase. As invasive predators occupy habitat on higher elevation Hawaiian Islands and globally important avian populations are concentrated on low-lying islands

  16. Challenges in Defining Tsunami Wave Height

    NASA Astrophysics Data System (ADS)

    Stroker, K. J.; Dunbar, P. K.; Mungov, G.; Sweeney, A.; Arcos, N. P.

    2017-12-01

    The NOAA National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global tsunami archive consisting of the historical tsunami database, imagery, and raw and processed water level data. The historical tsunami database incorporates, where available, maximum wave heights for each coastal tide gauge and deep-ocean buoy that recorded a tsunami signal. These data are important because they are used for tsunami hazard assessment, model calibration, validation, and forecast and warning. There have been ongoing discussions in the tsunami community about the correct way to measure and report these wave heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum wave height. On September 16, 2015, an 8.3 Mw earthquake located 48 km west of Illapel, Chile generated a tsunami that was observed all over the Pacific region. We processed the time-series water level data for 57 tide gauges that recorded this tsunami and compared the maximum wave heights determined from different definitions. We also compared the maximum wave heights from the NCEI-processed data with the heights reported by the NOAA Tsunami Warning Centers. We found that in the near field different methods of determining the maximum tsunami wave heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were <20 cm. For this event, the maximum tsunami wave heights determined by either definition (maximum peak or amplitude) would have validated the forecasts issued by the NOAA Tsunami Warning Centers. Since there is currently only one field in the NCEI historical tsunami database to store the maximum tsunami wave height, NCEI will consider adding an additional field for the maximum peak measurement.

  17. Coastal Amplification Laws for the French Tsunami Warning Center: Numerical Modeling and Fast Estimate of Tsunami Wave Heights Along the French Riviera

    NASA Astrophysics Data System (ADS)

    Gailler, A.; Hébert, H.; Schindelé, F.; Reymond, D.

    2017-11-01

    Tsunami modeling tools in the French tsunami Warning Center operational context provide rapidly derived warning levels with a dimensionless variable at basin scale. A new forecast method based on coastal amplification laws has been tested to estimate the tsunami onshore height, with a focus on the French Riviera test-site (Nice area). This fast prediction tool provides a coastal tsunami height distribution, calculated from the numerical simulation of the deep ocean tsunami amplitude and using a transfer function derived from the Green's law. Due to a lack of tsunami observations in the western Mediterranean basin, coastal amplification parameters are here defined regarding high resolution nested grids simulations. The preliminary results for the Nice test site on the basis of nine historical and synthetic sources show a good agreement with the time-consuming high resolution modeling: the linear approximation is obtained within 1 min in general and provides estimates within a factor of two in amplitude, although the resonance effects in harbors and bays are not reproduced. In Nice harbor especially, variation in tsunami amplitude is something that cannot be really assessed because of the magnitude range and maximum energy azimuth of possible events to account for. However, this method is well suited for a fast first estimate of the coastal tsunami threat forecast.

  18. Coastal amplification laws for the French tsunami Warning Center: numerical modeling and fast estimate of tsunami wave heights along the French Riviera

    NASA Astrophysics Data System (ADS)

    Gailler, A.; Schindelé, F.; Hebert, H.; Reymond, D.

    2017-12-01

    Tsunami modeling tools in the French tsunami Warning Center operational context provide for now warning levels with a no dimension scale, and at basin scale. A new forecast method based on coastal amplification laws has been tested to estimate the tsunami onshore height, with a focus on the French Riviera test-site (Nice area). This fast prediction tool provides a coastal tsunami height distribution, calculated from the numerical simulation of the deep ocean tsunami amplitude and using a transfer function derived from the Green's law. Due to a lack of tsunami observation in the western Mediterranean basin, coastal amplification parameters are here defined regarding high resolution nested grids simulations. The first encouraging results for the Nice test site on the basis of 9 historical and fake sources show a good agreement with the time-consuming high resolution modeling: the linear approximation provides within in general 1 minute estimates less a factor of 2 in amplitude, although the resonance effects in harbors and bays are not reproduced. In Nice harbor especially, variation in tsunami amplitude is something that cannot be really appreciated because of the magnitude range and maximum energy azimuth of possible events to account for. However, this method suits well for a fast first estimate of the coastal tsunami threat forecast.

  19. Coastal Amplification Laws for the French Tsunami Warning Center: Numerical Modeling and Fast Estimate of Tsunami Wave Heights Along the French Riviera

    NASA Astrophysics Data System (ADS)

    Gailler, A.; Hébert, H.; Schindelé, F.; Reymond, D.

    2018-04-01

    Tsunami modeling tools in the French tsunami Warning Center operational context provide rapidly derived warning levels with a dimensionless variable at basin scale. A new forecast method based on coastal amplification laws has been tested to estimate the tsunami onshore height, with a focus on the French Riviera test-site (Nice area). This fast prediction tool provides a coastal tsunami height distribution, calculated from the numerical simulation of the deep ocean tsunami amplitude and using a transfer function derived from the Green's law. Due to a lack of tsunami observations in the western Mediterranean basin, coastal amplification parameters are here defined regarding high resolution nested grids simulations. The preliminary results for the Nice test site on the basis of nine historical and synthetic sources show a good agreement with the time-consuming high resolution modeling: the linear approximation is obtained within 1 min in general and provides estimates within a factor of two in amplitude, although the resonance effects in harbors and bays are not reproduced. In Nice harbor especially, variation in tsunami amplitude is something that cannot be really assessed because of the magnitude range and maximum energy azimuth of possible events to account for. However, this method is well suited for a fast first estimate of the coastal tsunami threat forecast.

  20. Research to Operations: From Point Positions, Earthquake and Tsunami Modeling to GNSS-augmented Tsunami Early Warning

    NASA Astrophysics Data System (ADS)

    Stough, T.; Green, D. S.

    2017-12-01

    This collaborative research to operations demonstration brings together the data and algorithms from NASA research, technology, and applications-funded projects to deliver relevant data streams, algorithms, predictive models, and visualization tools to the NOAA National Tsunami Warning Center (NTWC) and Pacific Tsunami Warning Center (PTWC). Using real-time GNSS data and models in an operational environment, we will test and evaluate an augmented capability for tsunami early warning. Each of three research groups collect data from a selected network of real-time GNSS stations, exchange data consisting of independently processed 1 Hz station displacements, and merge the output into a single, more accurate and reliable set. The resulting merged data stream is delivered from three redundant locations to the TWCs with a latency of 5-10 seconds. Data from a number of seismogeodetic stations with collocated GPS and accelerometer instruments are processed for displacements and seismic velocities and also delivered. Algorithms for locating and determining the magnitude of earthquakes as well as algorithms that compute the source function of a potential tsunami using this new data stream are included in the demonstration. The delivered data, algorithms, models and tools are hosted on NOAA-operated machines at both warning centers, and, once tested, the results will be evaluated for utility in improving the speed and accuracy of tsunami warnings. This collaboration has the potential to dramatically improve the speed and accuracy of the TWCs local tsunami information over the current seismometer-only based methods. In our first year of this work, we have established and deployed an architecture for data movement and algorithm installation at the TWC's. We are addressing data quality issues and porting algorithms into the TWCs operating environment. Our initial module deliveries will focus on estimating moment magnitude (Mw) from Peak Ground Displacement (PGD), within 2

  1. Should tsunami models use a nonzero initial condition for horizontal velocity?

    NASA Astrophysics Data System (ADS)

    Nava, G.; Lotto, G. C.; Dunham, E. M.

    2017-12-01

    Tsunami propagation in the open ocean is most commonly modeled by solving the shallow water wave equations. These equations require two initial conditions: one on sea surface height and another on depth-averaged horizontal particle velocity or, equivalently, horizontal momentum. While most modelers assume that initial velocity is zero, Y.T. Song and collaborators have argued for nonzero initial velocity, claiming that horizontal displacement of a sloping seafloor imparts significant horizontal momentum to the ocean. They show examples in which this effect increases the resulting tsunami height by a factor of two or more relative to models in which initial velocity is zero. We test this claim with a "full-physics" integrated dynamic rupture and tsunami model that couples the elastic response of the Earth to the linearized acoustic-gravitational response of a compressible ocean with gravity; the model self-consistently accounts for seismic waves in the solid Earth, acoustic waves in the ocean, and tsunamis (with dispersion at short wavelengths). We run several full-physics simulations of subduction zone megathrust ruptures and tsunamis in geometries with a sloping seafloor, using both idealized structures and a more realistic Tohoku structure. Substantial horizontal momentum is imparted to the ocean, but almost all momentum is carried away in the form of ocean acoustic waves. We compare tsunami propagation in each full-physics simulation to that predicted by an equivalent shallow water wave simulation with varying assumptions regarding initial conditions. We find that the initial horizontal velocity conditions proposed by Song and collaborators consistently overestimate the tsunami amplitude and predict an inconsistent wave profile. Finally, we determine tsunami initial conditions that are rigorously consistent with our full-physics simulations by isolating the tsunami waves (from ocean acoustic and seismic waves) at some final time, and backpropagating the tsunami

  2. Modeling Earthquake Rupture and Corresponding Tsunamis Along a Segment of the Alaskan-Aleutian Megathrust

    NASA Astrophysics Data System (ADS)

    Ryan, K. J.; Geist, E. L.; Oglesby, D. D.; Kyriakopoulos, C.

    2016-12-01

    Motivated by the 2011 Mw 9 Tohoku-Oki event, we explore the effects of realistic fault dynamics on slip, free surface deformation, and the resulting tsunami generation and local propagation from a hypothetical Mw 9 megathrust earthquake along the Alaskan-Aleutian (A-A) Megathrust. We demonstrate three scenarios: a spatially-homogenous prestress and frictional parameter model and two models with rate-strengthening-like friction (e.g., Dieterich, 1992). We use a dynamic finite element code to model 3-D ruptures, using time-weakening friction (Andrews, 2004) as a proxy for rate-strengthening friction, along a portion of the A-A subduction zone. Given geometric, material, and plate-coupling data along the A-A megathrust assembled from the Science Application for Risk Reduction (SAFRR) team (e.g., Bruns et al., 1987; Hayes et al., 2012; Johnson et al., 2004; Santini et al., 2003; Wells at al., 2003), we are able to dynamically model rupture. Adding frictional-strengthening to a region of the fault reduces both average slip and free surface displacement above the strengthening zone, with the magnitude of the reductions depending on the strengthening zone location. Corresponding tsunami models, which use a finite difference method to solve the long-wave equations (e.g., Liu et al., 1995; Satake, 2002; Shuto, 1991), match sea floor displacement, in time, to the free surface displacement from the rupture models. Tsunami models show changes in local peak amplitudes and beaming patterns for each slip distribution. Given these results, other heterogeneous parameterizations, with respect to prestress and friction, still need to be examined. Additionally, a more realistic fault geometry will likely affect the rupture dynamics. Thus, future work will incorporate stochastic stress and friction distributions as well as a more complex fault geometry based on Slab 1.0 (Hayes et al., 2012).

  3. Three-dimensional splay fault geometry and implications for tsunami generation.

    PubMed

    Moore, G F; Bangs, N L; Taira, A; Kuramoto, S; Pangborn, E; Tobin, H J

    2007-11-16

    Megasplay faults, very long thrust faults that rise from the subduction plate boundary megathrust and intersect the sea floor at the landward edge of the accretionary prism, are thought to play a role in tsunami genesis. We imaged a megasplay thrust system along the Nankai Trough in three dimensions, which allowed us to map the splay fault geometry and its lateral continuity. The megasplay is continuous from the main plate interface fault upwards to the sea floor, where it cuts older thrust slices of the frontal accretionary prism. The thrust geometry and evidence of large-scale slumping of surficial sediments show that the fault is active and that the activity has evolved toward the landward direction with time, contrary to the usual seaward progression of accretionary thrusts. The megasplay fault has progressively steepened, substantially increasing the potential for vertical uplift of the sea floor with slip. We conclude that slip on the megasplay fault most likely contributed to generating devastating historic tsunamis, such as the 1944 moment magnitude 8.1 Tonankai event, and it is this geometry that makes this margin and others like it particularly prone to tsunami genesis.

  4. Field Survey in French Polynesia and Numerical Modeling of the 11 March 2011 Japan Tsunami

    NASA Astrophysics Data System (ADS)

    Hyvernaud, O.; Reymond, D.; Okal, E.; Hebert, H.; Clément, J.; Wong, K.

    2011-12-01

    We present the field survey and observations of the Japan tsunami of March 2011, in Society and Marquesas islands. Without being catastrophic the tsunami produced some damages in the Marquesas, which are always the most prone to tsunami amplification in French Polynesia: 8 houses were destroyed and inundated (up to 4.5 m of run-up measured). Surprisingly, the maximum run-up was observed on the South-West coast of Nuku Hiva island (a bay open to the opposite direction of the wave-front). In Tahiti, the tsunami was much more moderate, with a maximum height observed on the North coast: about 3 m of run-up observed, corresponding to the highest level of the seasonal oceanic swell without damage (just the main road inundated). These observations are well explained and reproduced by the numerical modeling of the tsunami. The results obtained confirm the exceptional source dimensions. Concerning the real time aspect, the tsunami height has been also rapidly predicted during the context of tsunami warning, with 2 methods: the first uses a database of pre-computed numeric simulations, and the second one uses a formula giving the tsunami amplitude in deep ocean in function of the source parameters (coordinates of the source, scalar moment and fault azimuth) and of the coordinates of the receiver. The population responded responsibly to the evacuation order on the 19 islands involved, helped in part by a favourable arrival time of the wave (7:30 a.m., local time).

  5. The 2004 Sumatra tsunami in the southeastern Pacific: Coastal and offshore measurements and numerical modeling

    NASA Astrophysics Data System (ADS)

    Moore, C. W.; Eble, M. C.; Rabinovich, A.; Titov, V. V.

    2016-12-01

    The Mw = 9.3 megathrust earthquake of December 26, 2004 off the coast of Sumatra generated a catastrophic tsunami that crossed the Indian Ocean and was widespread in the Pacific and Atlantic oceans being recorded by a great number of coastal tide gauges located in 15-25 thousand kilometers from the source area. The data from these instruments throughout the world oceans enabled estimates of various statistical parameters and energy decay of this event. However, only very few open-ocean records of this tsunami had been obtained. A unique high-resolution record of this tsunami from DART 32401 located offshore of northern Chile, combined with the South American mainland tide gauge measurements and the data from three island stations (San Felix, Juan Fernandez and Easter) enabled us to examine far-field characteristics of the event in the southeastern Pacific and to compare the results of global numerical simulations with observations. The maximum wave height measured at DART 32401 was only 1.8 cm but the signal was very clear and reliable. Despite their small heights, the waves demonstrated consistent spatial and temporal structure and good agreement with DART 46405/NeMO records in the NE Pacific. The travel time from the source area to DART 32401 was 25h 55min in good agreement with the computed travel time (25h 45min) and consistent with the times obtained from the nearby coastal tide gauges. This agreement was much better than it followed from the direct travel time estimation based classical kinematic theory that gave the travel time approximately 1.5 hrs shorter than observed. The later actual arrival of the 2004 tsunami waves corresponds to the most energetically economic path along the mid-ocean ridge wave-guides, which is distinctly reproduced by the numerical model. Also, the numerical model described well the frequency content, amplitudes and general structure of the observed waves at this DART and the three island stations. Maximum wave heights in this

  6. Incorporation of experimentally derived friction laws in numerical simulations of earthquake generated tsunamis

    NASA Astrophysics Data System (ADS)

    Murphy, Shane; Spagnuolo, Elena; Lorito, Stefano; Di Toro, Giulio; Scala, Antonio; Festa, Gaetano; Nielsen, Stefan; Piatanesi, Alessio; Romano, Fabrizio; Aretusini, Stefano

    2016-04-01

    Seismological, tsunami and geodetic observations have shown that subduction zones are complex systems where the properties of earthquake rupture vary with depth. For example nucleation and high frequency radiation generally occur at depth but low frequency radiation and large tsunami-genic slip appear to occur in the shallow crustal depth. Numerical simulations used to describe these features predominantly use standardised theoretical equations or experimental observations often assuming that their validity extends to all slip-rates, lithologies and tectonic environments. However recent rotary-shear experiments performed on a range of diverse materials and experimental conditions highlighted the large variability of the evolution of friction during slipping pointing to a more complex relationship between material type, slip rate and normal stress. Simulating dynamic rupture using a 2D spectral element methodology on a Tohoku like fault, we apply experimentally derived friction laws (i.e. thermal slip distance friction law, Di Toro et al. 2011) Choice of parameters for the friction law are based on expected material type (e.g. cohesive and non-cohesive clay rich material representative of an accretionary wedge), the normal stress which is controlled by the interaction between the regional stress field and the fault geometry. The shear stress distribution on the fault plane is fractal with the yield stress dependent on the static coefficient of friction and the normal stress, parameters that are dependent on the material type and geometry. We use metrics such as the slip distribution, ground motion and fracture energy to explore the effect of frictional behaviour, fault geometry and stress perturbations and its potential role in tsunami generation. Preliminary results will be presented. This research is funded by the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603839 (Project ASTARTE - Assessment, Strategy and Risk Reduction

  7. Tsunami Forecast Progress Five Years After Indonesian Disaster

    NASA Astrophysics Data System (ADS)

    Titov, Vasily V.; Bernard, Eddie N.; Weinstein, Stuart A.; Kanoglu, Utku; Synolakis, Costas E.

    2010-05-01

    Almost five years after the 26 December 2004 Indian Ocean tragedy, tsunami warnings are finally benefiting from decades of research toward effective model-based forecasts. Since the 2004 tsunami, two seminal advances have been (i) deep-ocean tsunami measurements with tsunameters and (ii) their use in accurately forecasting tsunamis after the tsunami has been generated. Using direct measurements of deep-ocean tsunami heights, assimilated into numerical models for specific locations, greatly improves the real-time forecast accuracy over earthquake-derived magnitude estimates of tsunami impact. Since 2003, this method has been used to forecast tsunamis at specific harbors for different events in the Pacific and Indian Oceans. Recent tsunamis illustrated how this technology is being adopted in global tsunami warning operations. The U.S. forecasting system was used by both research and operations to evaluate the tsunami hazard. Tests demonstrated the effectiveness of operational tsunami forecasting using real-time deep-ocean data assimilated into forecast models. Several examples also showed potential of distributed forecast tools. With IOC and USAID funding, NOAA researchers at PMEL developed the Community Model Interface for Tsunami (ComMIT) tool and distributed it through extensive capacity-building sessions in the Indian Ocean. Over hundred scientists have been trained in tsunami inundation mapping, leading to the first generation of inundation models for many Indian Ocean shorelines. These same inundation models can also be used for real-time tsunami forecasts as was demonstrated during several events. Contact Information Vasily V. Titov, Seattle, Washington, USA, 98115

  8. Analysis of geodetic interseismic coupling models to estimate tsunami inundation and runup: a study case of Maule seismic gap, Chile

    NASA Astrophysics Data System (ADS)

    González-Carrasco, J. F.; Gonzalez, G.; Aránguiz, R.; Catalan, P. A.; Cienfuegos, R.; Urrutia, A.; Shrivastava, M. N.; Yagi, Y.; Moreno, M.

    2015-12-01

    Tsunami inundation maps are a powerful tool to design evacuation plans of coastal communities, additionally can be used as a guide to territorial planning and assessment of structural damages in port facilities and critical infrastructure (Borrero et al., 2003; Barberopoulou et al., 2011; Power et al., 2012; Mueller et al., 2015). The accuracy of inundation estimation is highly correlated with tsunami initial conditions, e.g. seafloor vertical deformation, displaced water volume and potential energy (Bolshakova et al., 2011). Usually, the initial conditions are estimated using homogeneous rupture models based in historical worst-case scenario. However tsunamigenic events occurred in central Chilean continental margin showed a heterogeneous slip distribution of source with patches of high slip, correlated with fully-coupled interseismic zones (Moreno et al., 2012). The main objective of this work is to evaluate the predictive capacity of interseismic coupling models based on geodetic data comparing them with homogeneous fault slip model constructed using scaling laws (Blaser et al., 2010) to estimate inundation and runup in coastal areas. To test our hypothesis we select a seismic gap of Maule, where occurred the last large tsunamigenic earthquake in the chilean subduction zone, using the interseismic coupling models (ISC) proposed by Moreno et al., 2011 and Métois et al., 2013. We generate a slip deficit distribution to build a tsunami source supported by geological information such as slab depth (Hayes et al., 2012), strike, rake and dip (Dziewonski et al., 1981; Ekström et al., 2012) to model tsunami generation, propagation and shoreline impact using Neowave 2D (Yamazaki et al., 2009). We compare the tsunami scenario of Mw 8.8, Maule based in coseismic slip distribution proposed by Moreno et al., 2012 with homogeneous and heterogeneous models to identify the accuracy of our results with sea level time series and regional runup data (Figure 1). The estimation of

  9. Estimation of the Characterized Tsunami Source Model considering the Complicated Shape of Tsunami Source by Using the observed waveforms of GPS Buoys in the Nankai Trough

    NASA Astrophysics Data System (ADS)

    Seto, S.; Takahashi, T.

    2017-12-01

    In the 2011 Tohoku earthquake tsunami disaster, the delay of understanding damage situation increased the human damage. To solve this problem, it is important to search the severe damaged areas. The tsunami numerical modeling is useful to estimate damages and the accuracy of simulation depends on the tsunami source. Seto and Takahashi (2017) proposed a method to estimate the characterized tsunami source model by using the limited observed data of GPS buoys. The model consists of Large slip zone (LSZ), Super large slip zone (SLSZ) and background rupture zone (BZ) as the Cabinet Office, Government of Japan (below COGJ) reported after the Tohoku tsunami. At the beginning of this method, the rectangular fault model is assumed based on the seismic magnitude and hypocenter reported right after an earthquake. By using the fault model, tsunami propagation is simulated numerically, and the fault model is improved after comparing the computed data with the observed data repeatedly. In the comparison, correlation coefficient and regression coefficient are used as indexes. They are calculated with the observed and the computed tsunami wave profiles. This repetition is conducted to get the two coefficients close to 1.0, which makes the precise of the fault model higher. However, it was indicated as the improvement that the model did not examine a complicated shape of tsunami source. In this study, we proposed an improved model to examine the complicated shape. COGJ(2012) assumed that possible tsunami source region in the Nankai trough consisted of the several thousands small faults. And, we use these small faults to estimate the targeted tsunami source in this model. Therefore, we can estimate the complicated tsunami source by using these small faults. The estimation of BZ is carried out as a first step, and LSZ and SLSZ are estimated next as same as the previous model. The proposed model by using GPS buoy was applied for a tsunami scenario in the Nankai Trough. As a result

  10. Scenarios for earthquake-generated tsunamis on a complex tectonic area of diffuse deformation and low velocity: The Alboran Sea, Western Mediterranean

    USGS Publications Warehouse

    Alvarez-Gomez, J. A.; Aniel-Quiroga, I.; Gonzalez, M.; Olabarrieta, Maitane; Carreno, E.

    2011-01-01

    The tsunami impact on the Spanish and North African coasts of the Alboran Sea generated by several reliable seismic tsunamigenic sources in this area was modeled. The tectonic setting is complex and a study of the potential sources from geological data is basic to obtain probable source characteristics. The tectonic structures considered in this study as potentially tsunamigenic are: the Alboran Ridge associated structures, the Carboneras Fault Zone and the Yusuf Fault Zone. We characterized 12 probable tsunamigenic seismic sources in the Alboran Basin based on the results of recent oceanographical studies. The strain rate in the area is low and therefore its seismicity is moderate and cannot be used to infer characteristics of the major seismic sources. These sources have been used as input for the numerical simulation of the wave propagation, based on the solution of the nonlinear shallow water equations through a finite-difference technique. We calculated the Maximum Wave Elevations, and Tsunami Travel Times using the numerical simulations. The results are shown as maps and profiles along the Spanish and African coasts. The sources associated with the Alboran Ridge show the maximum potential to generate damaging tsunamis, with maximum wave elevations in front of the coast exceeding 1.5 m. The Carboneras and Yusuf faults are not capable of generating disastrous tsunamis on their own, although their proximity to the coast could trigger landslides and associated sea disturbances. The areas which are more exposed to the impact of tsunamis generated in the Alboran Sea are the Spanish coast between Malaga and Adra, and the African coast between Alhoceima and Melilla.

  11. Tsunami hazard assessment at Port Alberni, BC, Canada: preliminary model results

    NASA Astrophysics Data System (ADS)

    Grilli, S. T.; Insua, T. L.; Grilli, A. R.; Douglas, K. L.; Shelby, M. R.; Wang, K.; Gao, D.

    2016-12-01

    Located in the heart of Vancouver Island, BC, Port Alberni has a well-known history of tsunamis. Many of the Nuu-Chah-Nulth First Nations share oral stories about a strong fight between a thunderbird and a whale that caused big waves in a winter night, a story that is compatible with the recently recognized great Cascadia tsunami in January, 1700. Port Alberni, with a total population of approximately 20,000 people, lies beside the Somass River, at the very end of Barkley Sound Inlet. The narrow canal connecting this town to the Pacific Ocean runs for more than 64 km ( 40 miles) between steep mountains, providing an ideal setting for the amplification of tsunami waves through funnelling effects. The devastating effects of tsunamis are still fresh in residents' memories from the impact of the 1964 Alaska tsunami that caused serious damage to the city. In June 2016, Emergency Management BC ran a coastal exercise in Port Alberni, simulating the response to an earthquake and a tsunami. During three days, the emergency teams in the City of Port Alberni practiced and learned from the experience. Ocean Networks Canada contributed to this exercise with the development of preliminary simulations of tsunami impact on the city from a buried rupture of the Cascadia Subduction Zone, including the Explorer segment. Wave propagation was simulated with the long-wave model FUNWAVE-TVD. Preliminary results indicate a strong amplification of tsunami waves in the Port Alberni area. The inundation zone in Port Alberni had a footprint similar to that of the 1700 Cascadia and 1964 Alaska tsunamis, inundating the area surrounding the Somass river and preferentially following the Kitsuksis and Roger Creek river margins into the city. Several other tsunami source scenarios, including splay faulting and trench-breaching ruptures are currently being modeled for the city of Port Alberni following a similar approach. These results will be presented at the conference.

  12. Heterogeneous slip distribution on faults responsible for large earthquakes: characterization and implications for tsunami modelling

    NASA Astrophysics Data System (ADS)

    Baglione, Enrico; Armigliato, Alberto; Pagnoni, Gianluca; Tinti, Stefano

    2017-04-01

    The fact that ruptures on the generating faults of large earthquakes are strongly heterogeneous has been demonstrated over the last few decades by a large number of studies. The effort to retrieve reliable finite-fault models (FFMs) for large earthquakes occurred worldwide, mainly by means of the inversion of different kinds of geophysical data, has been accompanied in the last years by the systematic collection and format homogenisation of the published/proposed FFMs for different earthquakes into specifically conceived databases, such as SRCMOD. The main aim of this study is to explore characteristic patterns of the slip distribution of large earthquakes, by using a subset of the FFMs contained in SRCMOD, covering events with moment magnitude equal or larger than 6 and occurred worldwide over the last 25 years. We focus on those FFMs that exhibit a single and clear region of high slip (i.e. a single asperity), which is found to represent the majority of the events. For these FFMs, it sounds reasonable to best-fit the slip model by means of a 2D Gaussian distributions. Two different methods are used (least-square and highest-similarity) and correspondingly two "best-fit" indexes are introduced. As a result, two distinct 2D Gaussian distributions for each FFM are obtained. To quantify how well these distributions are able to mimic the original slip heterogeneity, we calculate and compare the vertical displacements at the Earth surface in the near field induced by the original FFM slip, by an equivalent uniform-slip model, by a depth-dependent slip model, and by the two "best" Gaussian slip models. The coseismic vertical surface displacement is used as the metric for comparison. Results show that, on average, the best results are the ones obtained with 2D Gaussian distributions based on similarity index fitting. Finally, we restrict our attention to those single-asperity FFMs associated to earthquakes which generated tsunamis. We choose few events for which tsunami

  13. Tsunamis generated by long and thin granular landslides in a large flume

    NASA Astrophysics Data System (ADS)

    Miller, Garrett S.; Andy Take, W.; Mulligan, Ryan P.; McDougall, Scott

    2017-01-01

    In this experimental study, granular material is released down slope to investigate landslide-generated waves. Starting with a known volume and initial position of the landslide source, detailed data are obtained on the velocity and thickness of the granular flow, the shape and location of the submarine landslide deposit, the amplitude and shape of the near-field wave, the far-field wave evolution, and the wave runup elevation on a smooth impermeable slope. The experiments are performed on a 6.7 m long 30° slope on which gravity accelerates the landslides into a 2.1 m wide and 33.0 m long wave flume that terminates with a 27° runup ramp. For a fixed landslide volume of 0.34 m3, tests are conducted in a range of still water depths from 0.05 to 0.50 m. Observations from high-speed cameras and measurements from wave probes indicate that the granular landslide moves as a long and thin train of material, and that only a portion of the landslide (termed the "effective mass") is engaged in activating the leading wave. The wave behavior is highly dependent on the water depth relative to the size of the landslide. In deeper water, the near-field wave behaves as a stable solitary-like wave, while in shallower water, the wave behaves as a breaking dissipative bore. Overall, the physical model observations are in good agreement with the results of existing empirical equations when the effective mass is used to predict the maximum near-field wave amplitude, the far-field amplitude, and the runup of tsunamis generated by granular landslides.

  14. Tsunami Source Model of the 2004 Sumatra-Andaman Earthquake inferred from Tide Gauge and Satellite Data

    NASA Astrophysics Data System (ADS)

    Fujii, Y.; Satake, K.

    2005-12-01

    The tsunami generation process of the 2004 Sumatra-Andaman earthquake were estimated from the tsunami waveforms recorded on tide gauges and sea surface heights captured by satellite altimetry measurements over the Indian Ocean. The earthquake (0:58:53, 26, Dec., 2004, UTC), the largest in the last 40 years, caused devastating tsunami damages to the countries around the Indian Ocean. One of the important questions is the source length; the aftershocks were distributed along the Sunda trench for 1000 to 1200 km, from off northwestern part of Sumatra island through Nicobar islands to Andaman island, while seismic wave analyses indicate much shorter source length (several hundred km). We used instrumental data of this tsunami, tide gauges and sea surface heights. Tide gauge data have been collected by Global Sea Level Observing System (GLOSS). We have also used another tide gauges data for tsunami simulation analysis. Tsunami propagation was captured as sea surface heights of Jason-1 satellite altimetry measurements over the Indian Ocean for the first time (Gower, 2005). We numerically compute tsunami propagation on actually bathymetry. ETOPO2 (Smith and Sandwell, 1997), the gridded data of global ocean depth from bathymetry soundings and satellite gravity data, are less reliable in the shallow ocean. To improve the accuracy, we have digitized the charts near coasts and merged the digitized data with the ETOPO2 data. The long-wave equation and the equation of motion were numerically solved by finite-difference method (Satake, 1995). As the initial condition, a static deformation of seafloor has been calculated using rectangular fault model (Okada, 1985). The source region is divided into 22 subfaults. We fixed the size and geometry of each subfault, and varied the slip amount and rise time (or slip duration) for each subfault, and rupture velocity. Tsunami waveforms or Greens functions for each subfault were calculated for the rise times of 3, 10, 30 and 60 minutes

  15. Evaluation of W Phase CMT Based PTWC Real-Time Tsunami Forecast Model Using DART Observations: Events of the Last Decade

    NASA Astrophysics Data System (ADS)

    Wang, D.; Becker, N. C.; Weinstein, S.; Duputel, Z.; Rivera, L. A.; Hayes, G. P.; Hirshorn, B. F.; Bouchard, R. H.; Mungov, G.

    2017-12-01

    The Pacific Tsunami Warning Center (PTWC) began forecasting tsunamis in real-time using source parameters derived from real-time Centroid Moment Tensor (CMT) solutions in 2009. Both the USGS and PTWC typically obtain W-Phase CMT solutions for large earthquakes less than 30 minutes after earthquake origin time. Within seconds, and often before waves reach the nearest deep ocean bottom pressure sensor (DARTs), PTWC then generates a regional tsunami propagation forecast using its linear shallow water model. The model is initialized by the sea surface deformation that mimics the seafloor deformation based on Okada's (1985) dislocation model of a rectangular fault with a uniform slip. The fault length and width are empirical functions of the seismic moment. How well did this simple model perform? The DART records provide a very valuable dataset for model validation. We examine tsunami events of the last decade with earthquake magnitudes ranging from 6.5 to 9.0 including some deep events for which tsunamis were not expected. Most of the forecast results were obtained during the events. We also include events from before the implementation of the WCMT method at USGS and PTWC, 2006-2009. For these events, WCMTs were computed retrospectively (Duputel et al. 2012). We also re-ran the model with a larger domain for some events to include far-field DARTs that recorded a tsunami with identical source parameters used during the events. We conclude that our model results, in terms of maximum wave amplitude, are mostly within a factor of two of the observed at DART stations, with an average error of less than 40% for most events, including the 2010 Maule and the 2011 Tohoku tsunamis. However, the simple fault model with a uniform slip is too simplistic for the Tohoku tsunami. We note model results are sensitive to centroid location and depth, especially if the earthquake is close to land or inland. For the 2016 M7.8 New Zealand earthquake the initial forecast underestimated the

  16. Source mechanisms of volcanic tsunamis.

    PubMed

    Paris, Raphaël

    2015-10-28

    Volcanic tsunamis are generated by a variety of mechanisms, including volcano-tectonic earthquakes, slope instabilities, pyroclastic flows, underwater explosions, shock waves and caldera collapse. In this review, we focus on the lessons that can be learnt from past events and address the influence of parameters such as volume flux of mass flows, explosion energy or duration of caldera collapse on tsunami generation. The diversity of waves in terms of amplitude, period, form, dispersion, etc. poses difficulties for integration and harmonization of sources to be used for numerical models and probabilistic tsunami hazard maps. In many cases, monitoring and warning of volcanic tsunamis remain challenging (further technical and scientific developments being necessary) and must be coupled with policies of population preparedness. © 2015 The Author(s).

  17. Application and Validation of a GIS Model for Local Tsunami Vulnerability and Mortality Risk Analysis

    NASA Astrophysics Data System (ADS)

    Harbitz, C. B.; Frauenfelder, R.; Kaiser, G.; Glimsdal, S.; Sverdrup-thygeson, K.; Løvholt, F.; Gruenburg, L.; Mc Adoo, B. G.

    2015-12-01

    The 2011 Tōhoku tsunami caused a high number of fatalities and massive destruction. Data collected after the event allow for retrospective analyses. Since 2009, NGI has developed a generic GIS model for local analyses of tsunami vulnerability and mortality risk. The mortality risk convolves the hazard, exposure, and vulnerability. The hazard is represented by the maximum tsunami flow depth (with a corresponding likelihood), the exposure is described by the population density in time and space, while the vulnerability is expressed by the probability of being killed as a function of flow depth and building class. The analysis is further based on high-resolution DEMs. Normally a certain tsunami scenario with a corresponding return period is applied for vulnerability and mortality risk analysis. Hence, the model was first employed for a tsunami forecast scenario affecting Bridgetown, Barbados, and further developed in a forecast study for the city of Batangas in the Philippines. Subsequently, the model was tested by hindcasting the 2009 South Pacific tsunami in American Samoa. This hindcast was based on post-tsunami information. The GIS model was adapted for optimal use of the available data and successfully estimated the degree of mortality.For further validation and development, the model was recently applied in the RAPSODI project for hindcasting the 2011 Tōhoku tsunami in Sendai and Ishinomaki. With reasonable choices of building vulnerability, the estimated expected number of fatalities agree well with the reported death toll. The results of the mortality hindcast for the 2011 Tōhoku tsunami substantiate that the GIS model can help to identify high tsunami mortality risk areas, as well as identify the main risk drivers.The research leading to these results has received funding from CONCERT-Japan Joint Call on Efficient Energy Storage and Distribution/Resilience against Disasters (http://www.concertjapan.eu; project RAPSODI - Risk Assessment and design of

  18. Probabilistic tsunami inundation map based on stochastic earthquake source model: A demonstration case in Macau, the South China Sea

    NASA Astrophysics Data System (ADS)

    Li, Linlin; Switzer, Adam D.; Wang, Yu; Chan, Chung-Han; Qiu, Qiang; Weiss, Robert

    2017-04-01

    Current tsunami inundation maps are commonly generated using deterministic scenarios, either for real-time forecasting or based on hypothetical "worst-case" events. Such maps are mainly used for emergency response and evacuation planning and do not include the information of return period. However, in practice, probabilistic tsunami inundation maps are required in a wide variety of applications, such as land-use planning, engineer design and for insurance purposes. In this study, we present a method to develop the probabilistic tsunami inundation map using a stochastic earthquake source model. To demonstrate the methodology, we take Macau a coastal city in the South China Sea as an example. Two major advances of this method are: it incorporates the most updated information of seismic tsunamigenic sources along the Manila megathrust; it integrates a stochastic source model into a Monte Carlo-type simulation in which a broad range of slip distribution patterns are generated for large numbers of synthetic earthquake events. When aggregated the large amount of inundation simulation results, we analyze the uncertainties associated with variability of earthquake rupture location and slip distribution. We also explore how tsunami hazard evolves in Macau in the context of sea level rise. Our results suggest Macau faces moderate tsunami risk due to its low-lying elevation, extensive land reclamation, high coastal population and major infrastructure density. Macau consists of four districts: Macau Peninsula, Taipa Island, Coloane island and Cotai strip. Of these Macau Peninsula is the most vulnerable to tsunami due to its low-elevation and exposure to direct waves and refracted waves from the offshore region and reflected waves from mainland. Earthquakes with magnitude larger than Mw8.0 in the northern Manila trench would likely cause hazardous inundation in Macau. Using a stochastic source model, we are able to derive a spread of potential tsunami impacts for earthquakes

  19. Validation of tsunami inundation model TUNA-RP using OAR-PMEL-135 benchmark problem set

    NASA Astrophysics Data System (ADS)

    Koh, H. L.; Teh, S. Y.; Tan, W. K.; Kh'ng, X. Y.

    2017-05-01

    A standard set of benchmark problems, known as OAR-PMEL-135, is developed by the US National Tsunami Hazard Mitigation Program for tsunami inundation model validation. Any tsunami inundation model must be tested for its accuracy and capability using this standard set of benchmark problems before it can be gainfully used for inundation simulation. The authors have previously developed an in-house tsunami inundation model known as TUNA-RP. This inundation model solves the two-dimensional nonlinear shallow water equations coupled with a wet-dry moving boundary algorithm. This paper presents the validation of TUNA-RP against the solutions provided in the OAR-PMEL-135 benchmark problem set. This benchmark validation testing shows that TUNA-RP can indeed perform inundation simulation with accuracy consistent with that in the tested benchmark problem set.

  20. Tsunami forecast by joint inversion of real-time tsunami waveforms and seismic of GPS data: application to the Tohoku 2011 tsunami

    USGS Publications Warehouse

    Yong, Wei; Newman, Andrew V.; Hayes, Gavin P.; Titov, Vasily V.; Tang, Liujuan

    2014-01-01

    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.

  1. Mathematical modelling of tsunami impacts on critical infrastructures: exposure and severity associated with debris transport at Sines port, Portugal.

    NASA Astrophysics Data System (ADS)

    Conde, Daniel; Baptista, Maria Ana; Sousa Oliveira, Carlos; Ferreira, Rui M. L.

    2015-04-01

    Global energy production is still significantly dependant on the coal supply chain, justifying huge investments on building infrastructures, capable of stocking very large quantities of this natural resource. Most of these infrastructures are located at deep-sea ports and are therefore exposed to extreme coastal hazards, such as tsunami impacts. The 2011 Tohoku tsunami is reported to have inflicted severe damage to Japan's coal-fired power stations and related infrastructure. Sines, located in the Portuguese coast, hosts a major commercial port featuring an exposed coal stockpile area extending over more than 24 ha and a container terminal currently under expansion up to 100ha. It is protected against storm surges but tsunamis have not been considered in the design criteria. The dominant wind-generated wave direction is N to NW, while the main tsunamigenic faults are located S to SW of the port. This configuration potentially exposes sensitive facilities, such as the new terminal container and the coal stockpile area. According to a recent revision of the national tsunami catalogue (Baptista, 2009), Portugal has been affected by numerous major tsunamis over the last two millennia, with the most notorious event being the Great Lisbon Earthquake and Tsunami occurred on the 1st November 1755. The aim of this work is to simulate the open ocean propagation and overland impact of a tsunami on the Sines port, similar to the historical event of 1755, based on the different tsunamigenic faults and magnitudes proposed in the current literature. Open ocean propagation was modelled with standard simulation tools like TUNAMI and GeoClaw. Near-shore and overland propagation was carried out using a recent 2DH mathematical model for solid-fluid flows, STAV-2D from CERIS-IST (Ferreira et al., 2009; Canelas, 2013). STAV-2D is particularly suited for tsunami propagation over complex and morphodynamic geometries, featuring a discretization scheme based on a finite-volume method using

  2. Probabilistic tsunami hazard analysis: Multiple sources and global applications

    USGS Publications Warehouse

    Grezio, Anita; Babeyko, Andrey; Baptista, Maria Ana; Behrens, Jörn; Costa, Antonio; Davies, Gareth; Geist, Eric L.; Glimsdal, Sylfest; González, Frank I.; Griffin, Jonathan; Harbitz, Carl B.; LeVeque, Randall J.; Lorito, Stefano; Løvholt, Finn; Omira, Rachid; Mueller, Christof; Paris, Raphaël; Parsons, Thomas E.; Polet, Jascha; Power, William; Selva, Jacopo; Sørensen, Mathilde B.; Thio, Hong Kie

    2017-01-01

    Applying probabilistic methods to infrequent but devastating natural events is intrinsically challenging. For tsunami analyses, a suite of geophysical assessments should be in principle evaluated because of the different causes generating tsunamis (earthquakes, landslides, volcanic activity, meteorological events, and asteroid impacts) with varying mean recurrence rates. Probabilistic Tsunami Hazard Analyses (PTHAs) are conducted in different areas of the world at global, regional, and local scales with the aim of understanding tsunami hazard to inform tsunami risk reduction activities. PTHAs enhance knowledge of the potential tsunamigenic threat by estimating the probability of exceeding specific levels of tsunami intensity metrics (e.g., run-up or maximum inundation heights) within a certain period of time (exposure time) at given locations (target sites); these estimates can be summarized in hazard maps or hazard curves. This discussion presents a broad overview of PTHA, including (i) sources and mechanisms of tsunami generation, emphasizing the variety and complexity of the tsunami sources and their generation mechanisms, (ii) developments in modeling the propagation and impact of tsunami waves, and (iii) statistical procedures for tsunami hazard estimates that include the associated epistemic and aleatoric uncertainties. Key elements in understanding the potential tsunami hazard are discussed, in light of the rapid development of PTHA methods during the last decade and the globally distributed applications, including the importance of considering multiple sources, their relative intensities, probabilities of occurrence, and uncertainties in an integrated and consistent probabilistic framework.

  3. Probabilistic Tsunami Hazard Analysis: Multiple Sources and Global Applications

    NASA Astrophysics Data System (ADS)

    Grezio, Anita; Babeyko, Andrey; Baptista, Maria Ana; Behrens, Jörn; Costa, Antonio; Davies, Gareth; Geist, Eric L.; Glimsdal, Sylfest; González, Frank I.; Griffin, Jonathan; Harbitz, Carl B.; LeVeque, Randall J.; Lorito, Stefano; Løvholt, Finn; Omira, Rachid; Mueller, Christof; Paris, Raphaël.; Parsons, Tom; Polet, Jascha; Power, William; Selva, Jacopo; Sørensen, Mathilde B.; Thio, Hong Kie

    2017-12-01

    Applying probabilistic methods to infrequent but devastating natural events is intrinsically challenging. For tsunami analyses, a suite of geophysical assessments should be in principle evaluated because of the different causes generating tsunamis (earthquakes, landslides, volcanic activity, meteorological events, and asteroid impacts) with varying mean recurrence rates. Probabilistic Tsunami Hazard Analyses (PTHAs) are conducted in different areas of the world at global, regional, and local scales with the aim of understanding tsunami hazard to inform tsunami risk reduction activities. PTHAs enhance knowledge of the potential tsunamigenic threat by estimating the probability of exceeding specific levels of tsunami intensity metrics (e.g., run-up or maximum inundation heights) within a certain period of time (exposure time) at given locations (target sites); these estimates can be summarized in hazard maps or hazard curves. This discussion presents a broad overview of PTHA, including (i) sources and mechanisms of tsunami generation, emphasizing the variety and complexity of the tsunami sources and their generation mechanisms, (ii) developments in modeling the propagation and impact of tsunami waves, and (iii) statistical procedures for tsunami hazard estimates that include the associated epistemic and aleatoric uncertainties. Key elements in understanding the potential tsunami hazard are discussed, in light of the rapid development of PTHA methods during the last decade and the globally distributed applications, including the importance of considering multiple sources, their relative intensities, probabilities of occurrence, and uncertainties in an integrated and consistent probabilistic framework.

  4. Seismic Shaking, Tsunami Wave Erosion And Generation of Seismo-Turbidites in the Ionian Sea

    NASA Astrophysics Data System (ADS)

    Polonia, Alina; Nelson, Hans; Romano, Stefania; Vaiani, Stefano Claudio; Colizza, Ester; Gasparotto, Giorgio; Gasperini, Luca

    2016-04-01

    We are investigating the effects of earthquakes and tsunamis on the sedimentary record in the Ionian Sea through the analysis of turbidite deposits. A comparison between radiometric dating and historical earthquake catalogs suggests that recent turbidite generation is triggered by great earthquakes in the Calabrian and hellenic Arcs such as the AD 1908 Messina, AD 1693 Catania, AD 1169 Eastern Sicily and AD 365 Crete earthquakes. Textural, micropaleontological, geochemical and mineralogical signatures of the youngest three seismo-turbidites reveal cyclic patterns of sedimentary units. The basal stacked turbidites result from multiple slope failure sources as shown by different sedimentary structures as well as mineralogic, geochemical and micropaleontological compositions. The homogenite units, are graded muds deposited from the waning flows of the multiple turbidity currents that are trapped in the Ionian Sea confined basin. The uppermost unit is divided into two parts. The lower marine sourced laminated part without textural gradation, we interpret to result from seiching of the confined water mass that appears to be generated by earthquake ruptures combined with tsunami waves. The uppermost part we interpret as the tsunamite cap that is deposited by the slow settling suspension cloud created by tsunami wave backwash erosion of the shoreline and continental shelf. This tsunami process interpretation is based on the final textural gradation of the upper unit and a more continental source of the tsunami cap which includes C/N >10, the lack of abyssal foraminifera species wirth the local occurrence of inner shelf foraminifera. Seismic reflection images show that some deeper turbidite beds are very thick and marked by acoustic transparent homogenite mud layers at their top. Based on a high resolution study of the most recent of such megabeds (Homogenite/Augias turbidite, i.e. HAT), we show that it was triggered by the AD 365 Crete earthquake. Radiometric dating

  5. The 2004 Sumatra tsunami in the Southeastern Pacific Ocean: New Global Insight from Observations and Modeling

    NASA Astrophysics Data System (ADS)

    Rabinovich, A. B.; Titov, V. V.; Moore, C. W.; Eblé, M. C.

    2017-10-01

    The 2004 Sumatra tsunami was an unprecedented global disaster measured throughout the world oceans. The present study focused on a region of the southeastern Pacific Ocean where the "westward" circumferentially propagating tsunami branch converged with the "eastward" branch, based on data from fortuitously placed Chilean DART 32401 and tide gauges along the coast of South America. By comparison of the tsunami and background spectra, we suppressed the influence of topography and reconstructed coastal "spectral ratios" that were in close agreement with a ratio at DART 32401 and spectral ratios in other oceans. Findings indicate that even remote tsunami records carry spectral source signatures ("birth-marks"). The 2004 tsunami waves were found to occupy the broad frequency band of 0.25-10 cph with the prominent ratio peak at period of 40 min related to the southern fast-slip source domain. This rupture "hot-spot" of ˜350 km was responsible for the global impact of the 2004 tsunami. Data from DART 32401 provided validation of model results: the simulated maximum tsunami wave height of 2.25 cm was a conservative approximation to the measured height of 2.05 cm; the computed tsunami travel time of 25 h 35 min to DART 32401, although 20 min earlier than the actual travel time, provided a favorable result in comparison with 24 h 25 min estimated from classical kinematic theory. The numerical simulations consistently reproduced the wave height changes observed along the coast of South America, including local amplification of tsunami waves at the northern stations of Arica (72 cm) and Callao (67 cm).

  6. NOAA/West coast and Alaska Tsunami warning center Atlantic Ocean response criteria

    USGS Publications Warehouse

    Whitmore, P.; Refidaff, C.; Caropolo, M.; Huerfano-Moreno, V.; Knight, W.; Sammler, W.; Sandrik, A.

    2009-01-01

    West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakesoccurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake's location, magnitude, depth, distance from coastal locations, and precomputed threat estimates based on tsunami models computed from similar events. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of sub-sea landslides).The new criteria require development of a threat data base which sets warning or advisory zones based on location, magnitude, and pre-computed tsunami models. The models determine coastal tsunami amplitudes based on likely tsunami source parameters for a given event. Based on the computed amplitude, warning and advisory zones are pre-set.

  7. Effect of Sediments on Rupture Dynamics of Shallow Subduction Zone Earthquakes and Tsunami Generation

    NASA Astrophysics Data System (ADS)

    Ma, S.

    2011-12-01

    Low-velocity fault zones have long been recognized for crustal earthquakes by using fault-zone trapped waves and geodetic observations on land. However, the most pronounced low-velocity fault zones are probably in the subduction zones where sediments on the seafloor are being continuously subducted. In this study I focus on shallow subduction zone earthquakes; these earthquakes pose a serious threat to human society in their ability in generating large tsunamis. Numerous observations indicate that these earthquakes have unusually long rupture durations, low rupture velocities, and/or small stress drops near the trench. However, the underlying physics is unclear. I will use dynamic rupture simulations with a finite-element method to investigate the dynamic stress evolution on faults induced by both sediments and free surface, and its relations with rupture velocity and slip. I will also explore the effect of off-fault yielding of sediments on the rupture characteristics and seafloor deformation. As shown in Ma and Beroza (2008), the more compliant hanging wall combined with free surface greatly increases the strength drop and slip near the trench. Sediments in the subduction zone likely have a significant role in the rupture dynamics of shallow subduction zone earthquakes and tsunami generation.

  8. Tsunami simulation method initiated from waveforms observed by ocean bottom pressure sensors for real-time tsunami forecast; Applied for 2011 Tohoku Tsunami

    NASA Astrophysics Data System (ADS)

    Tanioka, Yuichiro

    2017-04-01

    After tsunami disaster due to the 2011 Tohoku-oki great earthquake, improvement of the tsunami forecast has been an urgent issue in Japan. National Institute of Disaster Prevention is installing a cable network system of earthquake and tsunami observation (S-NET) at the ocean bottom along the Japan and Kurile trench. This cable system includes 125 pressure sensors (tsunami meters) which are separated by 30 km. Along the Nankai trough, JAMSTEC already installed and operated the cable network system of seismometers and pressure sensors (DONET and DONET2). Those systems are the most dense observation network systems on top of source areas of great underthrust earthquakes in the world. Real-time tsunami forecast has depended on estimation of earthquake parameters, such as epicenter, depth, and magnitude of earthquakes. Recently, tsunami forecast method has been developed using the estimation of tsunami source from tsunami waveforms observed at the ocean bottom pressure sensors. However, when we have many pressure sensors separated by 30km on top of the source area, we do not need to estimate the tsunami source or earthquake source to compute tsunami. Instead, we can initiate a tsunami simulation from those dense tsunami observed data. Observed tsunami height differences with a time interval at the ocean bottom pressure sensors separated by 30 km were used to estimate tsunami height distribution at a particular time. In our new method, tsunami numerical simulation was initiated from those estimated tsunami height distribution. In this paper, the above method is improved and applied for the tsunami generated by the 2011 Tohoku-oki great earthquake. Tsunami source model of the 2011 Tohoku-oki great earthquake estimated using observed tsunami waveforms, coseimic deformation observed by GPS and ocean bottom sensors by Gusman et al. (2012) is used in this study. The ocean surface deformation is computed from the source model and used as an initial condition of tsunami

  9. Concerns over modeling and warning capabilities in wake of Tohoku Earthquake and Tsunami

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2011-04-01

    Improved earthquake models, better tsunami modeling and warning capabilities, and a review of nuclear power plant safety are all greatly needed following the 11 March Tohoku earthquake and tsunami, according to scientists at the European Geosciences Union's (EGU) General Assembly, held 3-8 April in Vienna, Austria. EGU quickly organized a morning session of oral presentations and an afternoon panel discussion less than 1 month after the earthquake and the tsunami and the resulting crisis at Japan's Fukushima nuclear power plant, which has now been identified as having reached the same level of severity as the 1986 Chernobyl disaster. Many of the scientists at the EGU sessions expressed concern about the inability to have anticipated the size of the earthquake and the resulting tsunami, which appears likely to have caused most of the fatalities and damage, including damage to the nuclear plant.

  10. Widespread tsunami-like waves of 23-27 June in the Mediterranean and Black Seas generated by high-altitude atmospheric forcing.

    PubMed

    Šepić, Jadranka; Vilibić, Ivica; Rabinovich, Alexander B; Monserrat, Sebastian

    2015-06-29

    A series of tsunami-like waves of non-seismic origin struck several southern European countries during the period of 23 to 27 June 2014. The event caused considerable damage from Spain to Ukraine. Here, we show that these waves were long-period ocean oscillations known as meteorological tsunamis which are generated by intense small-scale air pressure disturbances. An unique atmospheric synoptic pattern was tracked propagating eastward over the Mediterranean and the Black seas in synchrony with onset times of observed tsunami waves. This pattern favoured generation and propagation of atmospheric gravity waves that induced pronounced tsunami-like waves through the Proudman resonance mechanism. This is the first documented case of a chain of destructive meteorological tsunamis occurring over a distance of thousands of kilometres. Our findings further demonstrate that these events represent potentially dangerous regional phenomena and should be included in tsunami warning systems.

  11. Widespread tsunami-like waves of 23-27 June in the Mediterranean and Black Seas generated by high-altitude atmospheric forcing

    PubMed Central

    Šepić, Jadranka; Vilibić, Ivica; Rabinovich, Alexander B.; Monserrat, Sebastian

    2015-01-01

    A series of tsunami-like waves of non-seismic origin struck several southern European countries during the period of 23 to 27 June 2014. The event caused considerable damage from Spain to Ukraine. Here, we show that these waves were long-period ocean oscillations known as meteorological tsunamis which are generated by intense small-scale air pressure disturbances. An unique atmospheric synoptic pattern was tracked propagating eastward over the Mediterranean and the Black seas in synchrony with onset times of observed tsunami waves. This pattern favoured generation and propagation of atmospheric gravity waves that induced pronounced tsunami-like waves through the Proudman resonance mechanism. This is the first documented case of a chain of destructive meteorological tsunamis occurring over a distance of thousands of kilometres. Our findings further demonstrate that these events represent potentially dangerous regional phenomena and should be included in tsunami warning systems. PMID:26119833

  12. Geodetic Imaging and Tsunami Modeling of the 2017 Coupled Landslide-Tsunami Event in Karrat Fjord, West Greenland.

    NASA Astrophysics Data System (ADS)

    Barba, M.; Willis, M. J.; Tiampo, K. F.; Lynett, P. J.; Mätzler, E.; Thorsøe, K.; Higman, B. M.; Thompson, J. A.; Morin, P. J.

    2017-12-01

    We use a combination of geodetic imaging techniques and modelling efforts to examine the June 2017 Karrat Fjord, West Greenland, landslide and tsunami event. Our efforts include analysis of pre-cursor motions extracted from Sentinal SAR interferometry that we improved with high-resolution Digital Surface Models derived from commercial imagery and geo-coded Structure from Motion analyses. We produce well constrained estimates of landslide volume through DSM differencing by improving the ArcticDEM coverage of the region, and provide modeled tsunami run-up estimates at villages around the region, constrained with in-situ observations provided by the Greenlandic authorities. Estimates of run-up at unoccupied coasts are derived using a blend of high resolution imagery and elevation models. We further detail post-failure slope stability for areas of interest around the Karrat Fjord region. Warming trends in the region from model and satellite analysis are combined with optical imagery to ascertain whether the influence of melting permafrost and the formation of small springs on a slight bench on the mountainside that eventually failed can be used as indicators of future events.

  13. Introduction to "Global Tsunami Science: Past and Future, Volume I"

    NASA Astrophysics Data System (ADS)

    Geist, Eric L.; Fritz, Hermann M.; Rabinovich, Alexander B.; Tanioka, Yuichiro

    2016-12-01

    Twenty-five papers on the study of tsunamis are included in Volume I of the PAGEOPH topical issue "Global Tsunami Science: Past and Future". Six papers examine various aspects of tsunami probability and uncertainty analysis related to hazard assessment. Three papers relate to deterministic hazard and risk assessment. Five more papers present new methods for tsunami warning and detection. Six papers describe new methods for modeling tsunami hydrodynamics. Two papers investigate tsunamis generated by non-seismic sources: landslides and meteorological disturbances. The final three papers describe important case studies of recent and historical events. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  14. An evaluation of onshore digital elevation models for tsunami inundation modelling

    NASA Astrophysics Data System (ADS)

    Griffin, J.; Latief, H.; Kongko, W.; Harig, S.; Horspool, N.; Hanung, R.; Rojali, A.; Maher, N.; Fountain, L.; Fuchs, A.; Hossen, J.; Upi, S.; Dewanto, S. E.; Cummins, P. R.

    2012-12-01

    Tsunami inundation models provide fundamental information about coastal areas that may be inundated in the event of a tsunami along with additional parameters such as flow depth and velocity. This can inform disaster management activities including evacuation planning, impact and risk assessment and coastal engineering. A fundamental input to tsunami inundation models is adigital elevation model (DEM). Onshore DEMs vary widely in resolution, accuracy, availability and cost. A proper assessment of how the accuracy and resolution of DEMs translates into uncertainties in modelled inundation is needed to ensure results are appropriately interpreted and used. This assessment can in turn informdata acquisition strategies depending on the purpose of the inundation model. For example, lower accuracy elevation data may give inundation results that are sufficiently accurate to plan a community's evacuation route but not sufficient to inform engineering of a vertical evacuation shelters. A sensitivity study is undertaken to assess the utility of different available onshore digital elevation models for tsunami inundation modelling. We compare airborne interferometric synthetic aperture radar (IFSAR), ASTER and SRTM against high resolution (<1 m horizontal resolution, < 0.15 m vertical accuracy) LiDAR or stereo-camera data in three Indonesian locations with different coastal morphologies (Padang, West Sumatra; Palu, Central Sulawesi; and Maumere, Flores), using three different computational codes (ANUGA, TUNAMI-N3 and TsunAWI). Tsunami inundation extents modelled with IFSAR are comparable with those modelled with the high resolution datasets and with historical tsunami run-up data. Large vertical errors (> 10 m) and poor resolution of the coastline in the ASTER and SRTM elevation models cause modelled inundation to be much less compared with models using better data and with observations. Therefore we recommend that ASTER and SRTM should not be used for modelling tsunami

  15. Modeling the 16 September 2015 Chile tsunami source with the inversion of deep-ocean tsunami records by means of the r - solution method

    NASA Astrophysics Data System (ADS)

    Voronina, Tatyana; Romanenko, Alexey; Loskutov, Artem

    2017-04-01

    The key point in the state-of-the-art in the tsunami forecasting is constructing a reliable tsunami source. In this study, we present an application of the original numerical inversion technique to modeling the tsunami sources of the 16 September 2015 Chile tsunami. The problem of recovering a tsunami source from remote measurements of the incoming wave in the deep-water tsunameters is considered as an inverse problem of mathematical physics in the class of ill-posed problems. This approach is based on the least squares and the truncated singular value decomposition techniques. The tsunami wave propagation is considered within the scope of the linear shallow-water theory. As in inverse seismic problem, the numerical solutions obtained by mathematical methods become unstable due to the presence of noise in real data. A method of r-solutions makes it possible to avoid instability in the solution to the ill-posed problem under study. This method seems to be attractive from the computational point of view since the main efforts are required only once for calculating the matrix whose columns consist of computed waveforms for each harmonic as a source (an unknown tsunami source is represented as a part of a spatial harmonics series in the source area). Furthermore, analyzing the singular spectra of the matrix obtained in the course of numerical calculations one can estimate the future inversion by a certain observational system that will allow offering a more effective disposition for the tsunameters with the help of precomputations. In other words, the results obtained allow finding a way to improve the inversion by selecting the most informative set of available recording stations. The case study of the 6 February 2013 Solomon Islands tsunami highlights a critical role of arranging deep-water tsunameters for obtaining the inversion results. Implementation of the proposed methodology to the 16 September 2015 Chile tsunami has successfully produced tsunami source model

  16. Applications of acoustic-gravity waves numerical modeling to tsunami signals observed by gravimetry satellites in very low orbit

    NASA Astrophysics Data System (ADS)

    Brissaud, Q.; Garcia, R.; Sladen, A.; Martin, R.; Komatitsch, D.

    2016-12-01

    Acoustic and gravity waves propagating in planetary atmospheres have been studied intensively as markers of specific phenomena (tectonic events, explosions) or as contributors to atmosphere dynamics. To get a better understanding of the physics behind these dynamic processes, both acoustic and gravity waves propagation should be modeled in an attenuating and windy 3D atmosphere from the ground all the way to the upper thermosphere. Thus, in order to provide an efficient numerical tool at the regional or global scale we introduce a high-order finite-difference time domain (FDTD) approach that relies on the linearized compressible Navier-Stokes equations with spatially non constant physical parameters (density, viscosities and speed of sound) and background velocities (wind). We present applications of these simulations to the propagation of gravity waves generated by tsunamis for realistic cases for which atmospheric models are extracted from empirical models including variations with altitude of atmospheric parameters, and tsunami forcing at the ocean surface is extracted from shallow water simulations. We describe the specific difficulties induced by the size of the simulation, the boundary conditions and the spherical geometry and compare the simulation outputs to data gathered by gravimetric satellites crossing gravity waves generated by tsunamis.

  17. Interdisciplinary modeling and analysis to reduce loss of life from tsunamis

    NASA Astrophysics Data System (ADS)

    Wood, N. J.

    2016-12-01

    Recent disasters have demonstrated the significant loss of life and community impacts that can occur from tsunamis. Minimizing future losses requires an integrated understanding of the range of potential tsunami threats, how individuals are specifically vulnerable to these threats, what is currently in place to improve their chances of survival, and what risk-reduction efforts could be implemented. This presentation will provide a holistic perspective of USGS research enabled by recent advances in geospatial modeling to assess and communicate population vulnerability to tsunamis and the range of possible interventions to reduce it. Integrated research includes efforts to characterize the magnitude and demography of at-risk individuals in tsunami-hazard zones, their evacuation potential based on landscape conditions, nature-based mitigation to improve evacuation potential, evacuation pathways and population demand at assembly areas, siting considerations for vertical-evacuation refuges, community implications of multiple evacuation zones, car-based evacuation modeling for distant tsunamis, and projected changes in population exposure to tsunamis over time. Collectively, this interdisciplinary research supports emergency managers in their efforts to implement targeted risk-reduction efforts based on local conditions and needs, instead of generic regional strategies that only focus on hazard attributes.

  18. Tsunami evacuation analysis, modelling and planning: application to the coastal area of El Salvador

    NASA Astrophysics Data System (ADS)

    Gonzalez-Riancho, Pino; Aguirre-Ayerbe, Ignacio; Aniel-Quiroga, Iñigo; Abad Herrero, Sheila; González Rodriguez, Mauricio; Larreynaga, Jeniffer; Gavidia, Francisco; Quetzalcoalt Gutiérrez, Omar; Álvarez-Gómez, Jose Antonio; Medina Santamaría, Raúl

    2014-05-01

    Advances in the understanding and prediction of tsunami impacts allow the development of risk reduction strategies for tsunami-prone areas. Conducting adequate tsunami risk assessments is essential, as the hazard, vulnerability and risk assessment results allow the identification of adequate, site-specific and vulnerability-oriented risk management options, with the formulation of a tsunami evacuation plan being one of the main expected results. An evacuation plan requires the analysis of the territory and an evaluation of the relevant elements (hazard, population, evacuation routes, and shelters), the modelling of the evacuation, and the proposal of alternatives for those communities located in areas with limited opportunities for evacuation. Evacuation plans, which are developed by the responsible authorities and decision makers, would benefit from a clear and straightforward connection between the scientific and technical information from tsunami risk assessments and the subsequent risk reduction options. Scientifically-based evacuation plans would translate into benefits for the society in terms of mortality reduction. This work presents a comprehensive framework for the formulation of tsunami evacuation plans based on tsunami vulnerability assessment and evacuation modelling. This framework considers (i) the hazard aspects (tsunami flooding characteristics and arrival time), (ii) the characteristics of the exposed area (people, shelters and road network), (iii) the current tsunami warning procedures and timing, (iv) the time needed to evacuate the population, and (v) the identification of measures to improve the evacuation process, such as the potential location for vertical evacuation shelters and alternative routes. The proposed methodological framework aims to bridge the gap between risk assessment and risk management in terms of tsunami evacuation, as it allows for an estimation of the degree of evacuation success of specific management options, as well as

  19. Simulation of landslide and tsunami of the 1741 Oshima-Oshima eruption in Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Ioki, K.; Yanagisawa, H.; Tanioka, Y.; Kawakami, G.; Kase, Y.; Nishina, K.; Hirose, W.; Ishimaru, S.

    2017-12-01

    The 1741 tsunami was generated by the Oshima-Oshima sector collapse in the southwestern Hokkaido, Japan. The tsunami caused great damage along the coast of Japan Sea in Oshima and Tsugaru peninsula and was the largest scale generated in the Japan sea. By the survey of tsunami deposits, at the coast of Okushiri Island and Hiyama in Hokkaido, tsunami deposits of this tsunami were found. In this study, the landslide and tsunami by the Oshima-Oshima eruption were modeled to explain distribution of debris deposits, tsunami heights by historical records, and distribution of tsunami deposits. First, region of landslide and debris deposits were made out from the bathymetry based on the bathymetry survey data (Satake and Kato, 2001) in the north slope of Oshima-Oshima. In addition, topography before the sector collapse and landslide volume were re-estimated. The volume of landslide was estimated at 2.2 km3. Based on those data, the landslide and tsunami were simulated using two-layer model considered soil mass and water mass. The model was made improvements the integrated model of landslide and tsunami (Yanagisawa et al., 2014). The angle of internal friction was calculated 4 cases, included the bottom friction term in soil mass, to affect the movement of landslide. The Manning's roughness coefficient was calculated 5 cases, included the bottom friction term in soil mass, to affect the generation of tsunami. By the parameter study, optimal solutions were found. As the results, soil mass slid slowly submarine slope and stopped after about 15 minutes. Distribution of computed debris deposits agree relatively well with region of debris deposits made out from the bathymetry. On the other hand, the first wave of tsunami was generated during 1 minute that soil mass was sliding. Calculated tsunami heights match with historical records along the coast of Okushiri and Hiyama in Hokkaido. Calculated inundation area of tsunami cover distribution of tsunami deposits found by tsunami

  20. New Measurements and Modeling Capability to Improve Real-time Forecast of Cascadia Tsunamis along U.S. West Coast

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Titov, V. V.; Bernard, E. N.; Spillane, M. C.

    2014-12-01

    The tragedies of 2004 Sumatra and 2011 Tohoku tsunamis exposed the limits of our knowledge in preparing for devastating tsunamis, especially in the near field. The 1,100-km coastline of the Pacific coast of North America has tectonic and geological settings similar to Sumatra and Japan. The geological records unambiguously show that the Cascadia fault had caused devastating tsunamis in the past and this geological process will cause tsunamis in the future. Existing observational instruments along the Cascadia Subduction Zone are capable of providing tsunami data within minutes of tsunami generation. However, this strategy requires separation of the tsunami signals from the overwhelming high-frequency seismic waves produced during a strong earthquake- a real technical challenge for existing operational tsunami observational network. A new-generation of nano-resolution pressure sensors can provide high temporal resolution of the earthquake and tsunami signals without loosing precision. The nano-resolution pressure sensor offers a state-of the-science ability to separate earthquake vibrations and other oceanic noise from tsunami waveforms, paving the way for accurate, early warnings of local tsunamis. This breakthrough underwater technology has been tested and verified for a couple of micro-tsunami events (Paros et al., 2011). Real-time forecast of Cascadia tsunamis is becoming a possibility with the development of nano-tsunameter technology. The present study provides an investigation on optimizing the placement of these new sensors so that the forecast time can be shortened.. The presentation will cover the optimization of an observational array to quickly detect and forecast a tsunami generated by a strong Cascadia earthquake, including short and long rupture scenarios. Lessons learned from the 2011 Tohoku tsunami will be examined to demonstrate how we can improve the local forecast using the new technology We expect this study to provide useful guideline for

  1. Introduction to “Global tsunami science: Past and future, Volume II”

    USGS Publications Warehouse

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2017-01-01

    Twenty-two papers on the study of tsunamis are included in Volume II of the PAGEOPH topical issue “Global Tsunami Science: Past and Future”. Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 (Eds., E. L. Geist, H. M. Fritz, A. B. Rabinovich, and Y. Tanioka). Three papers in Volume II focus on details of the 2011 and 2016 tsunami-generating earthquakes offshore of Tohoku, Japan. The next six papers describe important case studies and observations of recent and historical events. Four papers related to tsunami hazard assessment are followed by three papers on tsunami hydrodynamics and numerical modelling. Three papers discuss problems of tsunami warning and real-time forecasting. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: volcanic explosions, landslides, and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  2. Performance Comparison of NAMI DANCE and FLOW-3D® Models in Tsunami Propagation, Inundation and Currents using NTHMP Benchmark Problems

    NASA Astrophysics Data System (ADS)

    Velioglu Sogut, Deniz; Yalciner, Ahmet Cevdet

    2018-06-01

    Field observations provide valuable data regarding nearshore tsunami impact, yet only in inundation areas where tsunami waves have already flooded. Therefore, tsunami modeling is essential to understand tsunami behavior and prepare for tsunami inundation. It is necessary that all numerical models used in tsunami emergency planning be subject to benchmark tests for validation and verification. This study focuses on two numerical codes, NAMI DANCE and FLOW-3D®, for validation and performance comparison. NAMI DANCE is an in-house tsunami numerical model developed by the Ocean Engineering Research Center of Middle East Technical University, Turkey and Laboratory of Special Research Bureau for Automation of Marine Research, Russia. FLOW-3D® is a general purpose computational fluid dynamics software, which was developed by scientists who pioneered in the design of the Volume-of-Fluid technique. The codes are validated and their performances are compared via analytical, experimental and field benchmark problems, which are documented in the ``Proceedings and Results of the 2011 National Tsunami Hazard Mitigation Program (NTHMP) Model Benchmarking Workshop'' and the ``Proceedings and Results of the NTHMP 2015 Tsunami Current Modeling Workshop". The variations between the numerical solutions of these two models are evaluated through statistical error analysis.

  3. Near-Field Tsunami Models with Rapid Earthquake Source Inversions from Land and Ocean-Based Observations: The Potential for Forecast and Warning

    NASA Astrophysics Data System (ADS)

    Melgar, D.; Bock, Y.; Crowell, B. W.; Haase, J. S.

    2013-12-01

    Computation of predicted tsunami wave heights and runup in the regions adjacent to large earthquakes immediately after rupture initiation remains a challenging problem. Limitations of traditional seismological instrumentation in the near field which cannot be objectively employed for real-time inversions and the non-unique source inversion results are a major concern for tsunami modelers. Employing near-field seismic, GPS and wave gauge data from the Mw 9.0 2011 Tohoku-oki earthquake, we test the capacity of static finite fault slip models obtained from newly developed algorithms to produce reliable tsunami forecasts. First we demonstrate the ability of seismogeodetic source models determined from combined land-based GPS and strong motion seismometers to forecast near-source tsunamis in ~3 minutes after earthquake origin time (OT). We show that these models, based on land-borne sensors only tend to underestimate the tsunami but are good enough to provide a realistic first warning. We then demonstrate that rapid ingestion of offshore shallow water (100 - 1000 m) wave gauge data significantly improves the model forecasts and possible warnings. We ingest data from 2 near-source ocean-bottom pressure sensors and 6 GPS buoys into the earthquake source inversion process. Tsunami Green functions (tGFs) are generated using the GeoClaw package, a benchmarked finite volume code with adaptive mesh refinement. These tGFs are used for a joint inversion with the land-based data and substantially improve the earthquake source and tsunami forecast. Model skill is assessed by detailed comparisons of the simulation output to 2000+ tsunami runup survey measurements collected after the event. We update the source model and tsunami forecast and warning at 10 min intervals. We show that by 20 min after OT the tsunami is well-predicted with a high variance reduction to the survey data and by ~30 minutes a model that can be considered final, since little changed is observed afterwards, is

  4. Ionospheric detection of tsunami earthquakes: observation, modeling and ideas for future early warning

    NASA Astrophysics Data System (ADS)

    Occhipinti, G.; Manta, F.; Rolland, L.; Watada, S.; Makela, J. J.; Hill, E.; Astafieva, E.; Lognonne, P. H.

    2017-12-01

    Detection of ionospheric anomalies following the Sumatra and Tohoku earthquakes (e.g., Occhipinti 2015) demonstrated that ionosphere is sensitive to earthquake and tsunami propagation: ground and oceanic vertical displacement induces acoustic-gravity waves propagating within the neutral atmosphere and detectable in the ionosphere. Observations supported by modelling proved that ionospheric anomalies related to tsunamis are deterministic and reproducible by numerical modeling via the ocean/neutral-atmosphere/ionosphere coupling mechanism (Occhipinti et al., 2008). To prove that the tsunami signature in the ionosphere is routinely detected we show here perturbations of total electron content (TEC) measured by GPS and following tsunamigenic earthquakes from 2004 to 2011 (Rolland et al. 2010, Occhipinti et al., 2013), nominally, Sumatra (26 December, 2004 and 12 September, 2007), Chile (14 November, 2007), Samoa (29 September, 2009) and the recent Tohoku-Oki (11 Mars, 2011). Based on the observations close to the epicenter, mainly performed by GPS networks located in Sumatra, Chile and Japan, we highlight the TEC perturbation observed within the first 8 min after the seismic rupture. This perturbation contains information about the ground displacement, as well as the consequent sea surface displacement resulting in the tsunami. In addition to GNSS-TEC observations close to the epicenter, new exciting measurements in the far-field were performed by airglow measurement in Hawaii show the propagation of the internal gravity waves induced by the Tohoku tsunami (Occhipinti et al., 2011). This revolutionary imaging technique is today supported by two new observations of moderate tsunamis: Queen Charlotte (M: 7.7, 27 October, 2013) and Chile (M: 8.2, 16 September 2015). We finally detail here our recent work (Manta et al., 2017) on the case of tsunami alert failure following the Mw7.8 Mentawai event (25 October, 2010), and its twin tsunami alert response following the Mw7

  5. High Resolution Tsunami Modeling and Assessment of Harbor Resilience; Case Study in Istanbul

    NASA Astrophysics Data System (ADS)

    Cevdet Yalciner, Ahmet; Aytore, Betul; Gokhan Guler, Hasan; Kanoglu, Utku; Duzgun, Sebnem; Zaytsev, Andrey; Arikawa, Taro; Tomita, Takashi; Ozer Sozdinler, Ceren; Necmioglu, Ocal; Meral Ozel, Nurcan

    2014-05-01

    Ports and harbors are the major vulnerable coastal structures under tsunami attack. Resilient harbors against tsunami impacts are essential for proper, efficient and successful rescue operations and reduction of the loss of life and property by tsunami disasters. There are several critical coastal structures as such in the Marmara Sea. Haydarpasa and Yenikapi ports are located in the Marmara Sea coast of Istanbul. These two ports are selected as the sites of numerical experiments to test their resilience under tsunami impact. Cargo, container and ro-ro handlings, and short/long distance passenger transfers are the common services in both ports. Haydarpasa port has two breakwaters with the length of three kilometers in total. Yenikapi port has one kilometer long breakwater. The accurate resilience analysis needs high resolution tsunami modeling and careful assessment of the site. Therefore, building data with accurate coordinates of their foot prints and elevations are obtained. The high resolution bathymetry and topography database with less than 5m grid size is developed for modeling. The metadata of the several types of structures and infrastructure of the ports and environs are processed. Different resistances for the structures/buildings/infrastructures are controlled by assigning different friction coefficients in a friction matrix. Two different tsunami conditions - high expected and moderate expected - are selected for numerical modeling. The hybrid tsunami simulation and visualization codes NAMI DANCE, STOC-CADMAS System are utilized to solve all necessary tsunami parameters and obtain the spatial and temporal distributions of flow depth, current velocity, inundation distance and maximum water level in the study domain. Finally, the computed critical values of tsunami parameters are evaluated and structural performance of the port components are discussed in regard to a better resilience. ACKNOWLEDGEMENTS: Support by EU 603839 ASTARTE Project, UDAP-Ç-12

  6. Introduction to “Global tsunami science: Past and future, Volume III”

    USGS Publications Warehouse

    Rabinovich, Alexander B.; Fritz, Hermann M.; Tanioka, Yuichiro; Geist, Eric L.

    2018-01-01

    Twenty papers on the study of tsunamis are included in Volume III of the PAGEOPH topical issue “Global Tsunami Science: Past and Future”. Volume I of this topical issue was published as PAGEOPH, vol. 173, No. 12, 2016 and Volume II as PAGEOPH, vol. 174, No. 8, 2017. Two papers in Volume III focus on specific details of the 2009 Samoa and the 1923 northern Kamchatka tsunamis; they are followed by three papers related to tsunami hazard assessment for three different regions of the world oceans: South Africa, Pacific coast of Mexico and the northwestern part of the Indian Ocean. The next six papers are on various aspects of tsunami hydrodynamics and numerical modelling, including tsunami edge waves, resonant behaviour of compressible water layer during tsunamigenic earthquakes, dispersive properties of seismic and volcanically generated tsunami waves, tsunami runup on a vertical wall and influence of earthquake rupture velocity on maximum tsunami runup. Four papers discuss problems of tsunami warning and real-time forecasting for Central America, the Mediterranean coast of France, the coast of Peru, and some general problems regarding the optimum use of the DART buoy network for effective real-time tsunami warning in the Pacific Ocean. Two papers describe historical and paleotsunami studies in the Russian Far East. The final set of three papers importantly investigates tsunamis generated by non-seismic sources: asteroid airburst and meteorological disturbances. Collectively, this volume highlights contemporary trends in global tsunami research, both fundamental and applied toward hazard assessment and mitigation.

  7. Development Of New Databases For Tsunami Hazard Analysis In California

    NASA Astrophysics Data System (ADS)

    Wilson, R. I.; Barberopoulou, A.; Borrero, J. C.; Bryant, W. A.; Dengler, L. A.; Goltz, J. D.; Legg, M.; McGuire, T.; Miller, K. M.; Real, C. R.; Synolakis, C.; Uslu, B.

    2009-12-01

    The California Geological Survey (CGS) has partnered with other tsunami specialists to produce two statewide databases to facilitate the evaluation of tsunami hazard products for both emergency response and land-use planning and development. A robust, State-run tsunami deposit database is being developed that compliments and expands on existing databases from the National Geophysical Data Center (global) and the USGS (Cascadia). Whereas these existing databases focus on references or individual tsunami layers, the new State-maintained database concentrates on the location and contents of individual borings/trenches that sample tsunami deposits. These data provide an important observational benchmark for evaluating the results of tsunami inundation modeling. CGS is collaborating with and sharing the database entry form with other states to encourage its continued development beyond California’s coastline so that historic tsunami deposits can be evaluated on a regional basis. CGS is also developing an internet-based, tsunami source scenario database and forum where tsunami source experts and hydrodynamic modelers can discuss the validity of tsunami sources and their contribution to hazard assessments for California and other coastal areas bordering the Pacific Ocean. The database includes all distant and local tsunami sources relevant to California starting with the forty scenarios evaluated during the creation of the recently completed statewide series of tsunami inundation maps for emergency response planning. Factors germane to probabilistic tsunami hazard analyses (PTHA), such as event histories and recurrence intervals, are also addressed in the database and discussed in the forum. Discussions with other tsunami source experts will help CGS determine what additional scenarios should be considered in PTHA for assessing the feasibility of generating products of value to local land-use planning and development.

  8. Tsunami Modeling and Prediction Using a Data Assimilation Technique with Kalman Filters

    NASA Astrophysics Data System (ADS)

    Barnier, G.; Dunham, E. M.

    2016-12-01

    Earthquake-induced tsunamis cause dramatic damages along densely populated coastlines. It is difficult to predict and anticipate tsunami waves in advance, but if the earthquake occurs far enough from the coast, there may be enough time to evacuate the zones at risk. Therefore, any real-time information on the tsunami wavefield (as it propagates towards the coast) is extremely valuable for early warning systems. After the 2011 Tohoku earthquake, a dense tsunami-monitoring network (S-net) based on cabled ocean-bottom pressure sensors has been deployed along the Pacific coast in Northeastern Japan. Maeda et al. (GRL, 2015) introduced a data assimilation technique to reconstruct the tsunami wavefield in real time by combining numerical solution of the shallow water wave equations with additional terms penalizing the numerical solution for not matching observations. The penalty or gain matrix is determined though optimal interpolation and is independent of time. Here we explore a related data assimilation approach using the Kalman filter method to evolve the gain matrix. While more computationally expensive, the Kalman filter approach potentially provides more accurate reconstructions. We test our method on a 1D tsunami model derived from the Kozdon and Dunham (EPSL, 2014) dynamic rupture simulations of the 2011 Tohoku earthquake. For appropriate choices of model and data covariance matrices, the method reconstructs the tsunami wavefield prior to wave arrival at the coast. We plan to compare the Kalman filter method to the optimal interpolation method developed by Maeda et al. (GRL, 2015) and then to implement the method for 2D.

  9. Observations and Modeling of the 27 February 2010 Tsunami in Chile

    NASA Astrophysics Data System (ADS)

    Synolakis, C. E.; Fritz, H. M.; Petroff, C. M.; Catalan, P. A.; Cienfuegos, R.; Winckler, P.; Kalligeris, N.; Weiss, R.; Meneses, G.; Valderas-Bermejo, C.; Ebeling, C. W.; Papadopoulos, A.; Contreras, M.; Almar, R.; Dominguez, J. C.; Barrientos, S. E.

    2010-12-01

    from the 2007 Solomon Islands event. Preliminary modeling results, field observations, video recordings and satellite imagery are presented. The team interviewed numerous eyewitnesses and educated residents about tsunami hazards as community-based education and awareness are essential to save lives in locales at risk.

  10. Tsunami-induced boulder transport - combining physical experiments and numerical modelling

    NASA Astrophysics Data System (ADS)

    Oetjen, Jan; Engel, Max; May, Simon Matthias; Schüttrumpf, Holger; Brueckner, Helmut; Prasad Pudasaini, Shiva

    2016-04-01

    Coasts are crucial areas for living, economy, recreation, transportation, and various sectors of industry. Many of them are exposed to high-energy wave events. With regard to the ongoing population growth in low-elevation coastal areas, the urgent need for developing suitable management measures, especially for hazards like tsunamis, becomes obvious. These measures require supporting tools which allow an exact estimation of impact parameters like inundation height, inundation area, and wave energy. Focussing on tsunamis, geological archives can provide essential information on frequency and magnitude on a longer time scale in order to support coastal hazard management. While fine-grained deposits may quickly be altered after deposition, multi-ton coarse clasts (boulders) may represent an information source on past tsunami events with a much higher preservation potential. Applying numerical hydrodynamic coupled boulder transport models (BTM) is a commonly used approach to analyse characteristics (e.g. wave height, flow velocity) of the corresponding tsunami. Correct computations of tsunamis and the induced boulder transport can provide essential event-specific information, including wave heights, runup and direction. Although several valuable numerical models for tsunami-induced boulder transport exist (e. g. Goto et al., 2007; Imamura et al., 2008), some important basic aspects of both tsunami hydrodynamics and corresponding boulder transport have not yet been entirely understood. Therefore, our project aims at these questions in four crucial aspects of boulder transport by a tsunami: (i) influence of sediment load, (ii) influence of complex boulder shapes other than idealized rectangular shapes, (iii) momentum transfers between multiple boulders, and (iv) influence of non-uniform bathymetries and topographies both on tsunami and boulder. The investigation of these aspects in physical experiments and the correct implementation of an advanced model is an urgent need

  11. Multiscale Modelling of the 2011 Tohoku Tsunami with Fluidity: Coastal Inundation and Run-up.

    NASA Astrophysics Data System (ADS)

    Hill, J.; Martin-Short, R.; Piggott, M. D.; Candy, A. S.

    2014-12-01

    Tsunami-induced flooding represents one of the most dangerous natural hazards to coastal communities around the world, as exemplified by Tohoku tsunami of March 2011. In order to further understand this hazard and to design appropriate mitigation it is necessary to develop versatile, accurate software capable of simulating large scale tsunami propagation and interaction with coastal geomorphology on a local scale. One such software package is Fluidity, an open source, finite element, multiscale, code that is capable of solving the fully three dimensional Navier-Stokes equations on unstructured meshes. Such meshes are significantly better at representing complex coastline shapes than structured meshes and have the advantage of allowing variation in element size across a domain. Furthermore, Fluidity incorporates a novel wetting and drying algorithm, which enables accurate, efficient simulation of tsunami run-up over complex, multiscale, topography. Fluidity has previously been demonstrated to accurately simulate the 2011 Tohoku tsunami (Oishi et al 2013) , but its wetting and drying facility has not yet been tested on a geographical scale. This study makes use of Fluidity to simulate the 2011 Tohoku tsunami and its interaction with Japan's eastern shoreline, including coastal flooding. The results are validated against observations made by survey teams, aerial photographs and previous modelling efforts in order to evaluate Fluidity's current capabilities and suggest methods of future improvement. The code is shown to perform well at simulating flooding along the topographically complex Tohoku coast of Japan, with major deviations between model and observation arising mainly due to limitations imposed by bathymetry resolution, which could be improved in future. In theory, Fluidity is capable of full multiscale tsunami modelling, thus enabling researchers to understand both wave propagation across ocean basins and flooding of coastal landscapes down to interaction

  12. A shallow water model for the propagation of tsunami via Lattice Boltzmann method

    NASA Astrophysics Data System (ADS)

    Zergani, Sara; Aziz, Z. A.; Viswanathan, K. K.

    2015-01-01

    An efficient implementation of the lattice Boltzmann method (LBM) for the numerical simulation of the propagation of long ocean waves (e.g. tsunami), based on the nonlinear shallow water (NSW) wave equation is presented. The LBM is an alternative numerical procedure for the description of incompressible hydrodynamics and has the potential to serve as an efficient solver for incompressible flows in complex geometries. This work proposes the NSW equations for the irrotational surface waves in the case of complex bottom elevation. In recent time, equation involving shallow water is the current norm in modelling tsunami operations which include the propagation zone estimation. Several test-cases are presented to verify our model. Some implications to tsunami wave modelling are also discussed. Numerical results are found to be in excellent agreement with theory.

  13. Role of Compressibility on Tsunami Propagation

    NASA Astrophysics Data System (ADS)

    Abdolali, Ali; Kirby, James T.

    2017-12-01

    In the present paper, we aim to reduce the discrepancies between tsunami arrival times evaluated from tsunami models and real measurements considering the role of ocean compressibility. We perform qualitative studies to reveal the phase speed reduction rate via a modified version of the Mild Slope Equation for Weakly Compressible fluid (MSEWC) proposed by Sammarco et al. (2013). The model is validated against a 3-D computational model. Physical properties of surface gravity waves are studied and compared with those for waves evaluated from an incompressible flow solver over realistic geometry for 2011 Tohoku-oki event, revealing reduction in phase speed.Plain Language SummarySubmarine earthquakes and submarine mass failures (SMFs), can <span class="hlt">generate</span> long gravitational waves (or <span class="hlt">tsunamis</span>) that propagate at the free surface. <span class="hlt">Tsunami</span> waves can travel long distances and are known for their dramatic effects on coastal areas. Nowadays, numerical <span class="hlt">models</span> are used to reconstruct the tsunamigenic events for many scientific and socioeconomic aspects i.e. <span class="hlt">Tsunami</span> Early Warning Systems, inundation mapping, risk and hazard analysis, etc. A number of typically neglected parameters in these <span class="hlt">models</span> cause discrepancies between <span class="hlt">model</span> outputs and observations. Most of the <span class="hlt">tsunami</span> <span class="hlt">models</span> predict <span class="hlt">tsunami</span> arrival times at distant stations slightly early in comparison to observations. In this study, we show how ocean compressibility would affect the <span class="hlt">tsunami</span> wave propagation speed. In this framework, an efficient two-dimensional <span class="hlt">model</span> equation for the weakly compressible ocean has been developed, validated and tested for simplified and real cases against three dimensional and incompressible solvers. Taking the effect of compressibility, the phase speed of surface gravity waves is reduced compared to that of an incompressible fluid. Then, we used the <span class="hlt">model</span> for the case of devastating Tohoku-Oki 2011 <span class="hlt">tsunami</span> event, improving the <span class="hlt">model</span> accuracy. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PrOce.159..296R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PrOce.159..296R"><span>The <span class="hlt">tsunami</span> phenomenon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Röbke, B. R.; Vött, A.</p> <p>2017-12-01</p> <p>With human activity increasingly concentrating on coasts, <span class="hlt">tsunamis</span> (from Japanese tsu = harbour, nami = wave) are a major natural hazard to today's society. Stimulated by disastrous <span class="hlt">tsunami</span> impacts in recent years, for instance in south-east Asia (2004) or in Japan (2011), <span class="hlt">tsunami</span> science has significantly flourished, which has brought great advances in hazard assessment and mitigation plans. Based on <span class="hlt">tsunami</span> research of the last decades, this paper provides a thorough treatise on the <span class="hlt">tsunami</span> phenomenon from a geoscientific point of view. Starting with the wave features, <span class="hlt">tsunamis</span> are introduced as long shallow water waves or wave trains crossing entire oceans without major energy loss. At the coast, <span class="hlt">tsunamis</span> typically show wave shoaling, funnelling and resonance effects as well as a significant run-up and backflow. <span class="hlt">Tsunami</span> waves are caused by a sudden displacement of the water column due to a number of various trigger mechanisms. Such are earthquakes as the main trigger, submarine and subaerial mass wastings, volcanic activity, atmospheric disturbances (meteotsunamis) and cosmic impacts, as is demonstrated by giving corresponding examples from the past. <span class="hlt">Tsunamis</span> are known to have a significant sedimentary and geomorphological off- and onshore response. So-called tsunamites form allochthonous high-energy deposits that are left at the coast during <span class="hlt">tsunami</span> landfall. <span class="hlt">Tsunami</span> deposits show typical sedimentary features, as basal erosional unconformities, fining-upward and -landward, a high content of marine fossils, rip-up clasts from underlying units and mud caps, all reflecting the hydrodynamic processes during inundation. The on- and offshore behaviour of <span class="hlt">tsunamis</span> and related sedimentary processes can be simulated using hydro- and morphodynamic numerical <span class="hlt">models</span>. The paper provides an overview of the basic <span class="hlt">tsunami</span> <span class="hlt">modelling</span> techniques, including discretisation, guidelines for appropriate temporal and spatial resolution as well as the nesting method. Furthermore, the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70196715','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70196715"><span>Pedestrian evacuation <span class="hlt">modeling</span> to reduce vehicle use for distant <span class="hlt">tsunami</span> evacuations in Hawaiʻi</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wood, Nathan J.; Jones, Jamie; Peters, Jeff; Richards, Kevin</p> <p>2018-01-01</p> <p><span class="hlt">Tsunami</span> waves that arrive hours after <span class="hlt">generation</span> elsewhere pose logistical challenges to emergency managers due to the perceived abundance of time and inclination of evacuees to use vehicles. We use coastal communities on the island of Oʻahu (Hawaiʻi, USA) to demonstrate regional evacuation <span class="hlt">modeling</span> that can identify where successful pedestrian-based evacuations are plausible and where vehicle use could be discouraged. The island of Oʻahu has two <span class="hlt">tsunami</span>-evacuation zones (standard and extreme), which provides the opportunity to examine if recommended travel modes vary based on zone. Geospatial path distance <span class="hlt">models</span> are applied to estimate population exposure as a function of pedestrian travel time and speed out of evacuation zones. The use of the extreme zone triples the number of residents, employees, and facilities serving at-risk populations that would be encouraged to evacuate and slightly reduces the percentage of residents (98–76%) that could evacuate in less than 15 min at a plausible speed (with similar percentages for employees). Areas with lengthy evacuations are concentrated in the North Shore region for the standard zone but found all around the Oʻahu coastline for the extreme zone. The use of the extreme zone results in a 26% increase in the number of hotel visitors that would be encouraged to evacuate, and a 76% increase in the number of them that may require more than 15 min. <span class="hlt">Modeling</span> can identify where pedestrian evacuations are plausible; however, there are logistical and behavioral issues that warrant attention before localized evacuation procedures may be realistic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.6999B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.6999B"><span>The Samoa <span class="hlt">tsunami</span> of 29 September 2009: Field survey in Samoa and preliminary <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borrero, J. C.; Fritz, H. M.; Synolakis, C. E.; Weiss, R.; Okal, E. A.</p> <p>2010-05-01</p> <p>The Samoa <span class="hlt">tsunami</span> of 29 September 2009 caused considerable damage and 146 deaths in the country of [ex-Western] Samoa, where the last comparable event took place in 1917. Following the event, an International <span class="hlt">Tsunami</span> Survey Team was deployed and surveyed the inundation one week after the <span class="hlt">tsunami</span>. Our results revealed higher values of run-up and inundation on the Southern shore of Upolu, where run-up reached 14.5 m at Lepa and 11.4 m at Lalomanu, this latter village being eradicated, with a death toll of 61. By contrast, the Northern shore was largely spared. A similar pattern was observed on the island of Savaii, but with lower run-up values, and only 2 deaths. The higher death toll in Samoa, as compared to American Samoa probably results from the combination of terrain morphology (wider coastal plains leading to longer evacuation distances), the absence of a signage project, and an unfortunate reliance on motor vehicles leading to entrapment of victims along roads often parallel to the beach. A number of numerical simulations were conducted using several <span class="hlt">models</span> of the seismic source; they correctly predict a concentration of <span class="hlt">tsunami</span> energy at the Southeastern corner of the island of Upolu, but also at its Southwestern end, where surveyed run-up did not exceed 5 m. All <span class="hlt">models</span> correctly indicate that the northern coast, with the capital Apia, is spared by the <span class="hlt">tsunami</span>, even though it had reportedly been emphasized during mitigation exercises prior to the event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH43B1656A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH43B1656A"><span>Observed and <span class="hlt">modeled</span> <span class="hlt">tsunami</span> current velocities in Humboldt Bay and Crescent City Harbor, northern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Admire, A. R.; Dengler, L.; Crawford, G. B.; uslu, B. U.; Montoya, J.</p> <p>2012-12-01</p> <p> Crescent City were compared to calculated velocities from the Method of Splitting <span class="hlt">Tsunamis</span> (MOST) numerical <span class="hlt">model</span>. For Humboldt Bay, the 2010 <span class="hlt">model</span> <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> 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 <span class="hlt">model</span> 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 <span class="hlt">tsunami</span> currents for small to moderate events and can be used to calibrate and validate <span class="hlt">models</span> (i.e. MOST) in order to better predict hazardous <span class="hlt">tsunami</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21251344-application-nonlinear-shallow-water-model-tsunami-using-adomian-decomposition-method','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21251344-application-nonlinear-shallow-water-model-tsunami-using-adomian-decomposition-method"><span>Application of 2D-Nonlinear Shallow Water <span class="hlt">Model</span> of <span class="hlt">Tsunami</span> by using Adomian Decomposition Method</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Waewcharoen, Sribudh; Boonyapibanwong, Supachai; Koonprasert, Sanoe</p> <p>2008-09-01</p> <p>One of the most important questions in <span class="hlt">tsunami</span> <span class="hlt">modeling</span> is the estimation of <span class="hlt">tsunami</span> run-up heights at different points along a coastline. Methods for numerical simulation of <span class="hlt">tsunami</span> wave propagation in deep and shallow seas are well developed and have been widely used by many scientists (2001-2008). In this paper, we consider a two-dimensional nonlinear shallow water <span class="hlt">model</span> of <span class="hlt">tsunami</span> given by Tivon Jacobson is work [1]. u{sub t}+uu{sub x}+{nu}u{sub y} -c{sup 2}(h{sub x}+(h{sub b}){sub x}) {nu}{sub t}+u{nu}{sub x}+{nu}{nu}{sub y} = -c{sup 2}(h{sub y}+(h{sub b}){sub y}) h{sub t}+(hu){sub x}+(h{nu}){sub y} = 0 g-shore, h is surface elevation and s, tmore » is time, u is velocity of cross-shore, {nu} is velocity of along-shore, h is surface elevation and h{sub b} is function of shore. This is a nondimensionalized <span class="hlt">model</span> with the gravity g and constant reference depth H factored into c = {radical}(gH). We apply the Adomian Decompostion Method (ADM) to solve the <span class="hlt">tsunami</span> <span class="hlt">model</span>. This powerful method has been used to obtain explicit and numerical solutions of three types of diffusion-convection-reaction (DECR) equations. The ADM results for the <span class="hlt">tsunami</span> <span class="hlt">model</span> yield analytical solutions in terms of a rapidly convergent infinite power series. Symbolic computation, numerical results and graphs of solutions are obtained by Maple program.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH12A..08S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH12A..08S"><span><span class="hlt">Tsunami</span> on Sanriku Coast in 1586: Orphan or Ghost <span class="hlt">Tsunami</span> ?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Satake, K.</p> <p>2017-12-01</p> <p>The Peruvian earthquake on July 9, 1586 was the oldest earthquake that damaged Lima. The <span class="hlt">tsunami</span> height was assigned as 24 m in Callao and 1-2 m in Miyagi prefecture in Japan by Soloviev and Go (1975). Dorbath et al. (1990) studied historical earthquakes in Peru and estimated that the 1586 earthquake was similar to the 1974 event (Mw 8.1) with source length of 175 km. They referred two different <span class="hlt">tsunami</span> heights, 3. 7m and 24 m, in Callao, and judged that the latter was exaggerated. Okal et al. (2006) could not make a source <span class="hlt">model</span> to explain both <span class="hlt">tsunami</span> heights in Callao and Japan. More recently, Butler et al. (2017) estimated the age of coral boulders in Hawaii as AD 1572 +/- 21, speculated the <span class="hlt">tsunami</span> source in Aleutians, and attributed it to the source of the 1586 <span class="hlt">tsunami</span> in Japan. Historical <span class="hlt">tsunamis</span>, both near-field and far-field, have been documented along the Sanriku coast since 1586 (e.g., Watanabe, 1998). However, there is no written document for the 1586 <span class="hlt">tsunami</span> (Tsuji et al., 2013). Ninomiya (1960) compiled the historical <span class="hlt">tsunami</span> records on the Sanriku coast soon after the 1960 Chilean <span class="hlt">tsunami</span>, and correlated the legend of <span class="hlt">tsunami</span> in Tokura with the 1586 Peruvian earthquake, although he noted that the dates were different. About the legend, he referred to Kunitomi(1933) who compiled historical <span class="hlt">tsunami</span> data after the 1933 Showa Sanriku <span class="hlt">tsunami</span>. Kunitomi referred to "<span class="hlt">Tsunami</span> history of Miyagi prefecture" published after the 1896 Meiji Sanriku <span class="hlt">tsunami</span>. "<span class="hlt">Tsunami</span> history" described the earthquake and <span class="hlt">tsunami</span> damage of Tensho earthquake on January 18 (Gregorian),1586 in central Japan, and correlated the <span class="hlt">tsunami</span> legend in Tokura on June 30, 1586 (G). Following the 2011 Tohoku <span class="hlt">tsunami</span>, <span class="hlt">tsunami</span> legend in Tokura was studied again (Ebina, 2015). A local person published a story he heard from his grandfather that many small valleys were named following the 1611 <span class="hlt">tsunami</span>, which inundated further inland than the 2011 <span class="hlt">tsunami</span>. Ebina (2015), based on historical documents</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70030808','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70030808"><span>Case study: Mapping <span class="hlt">tsunami</span> hazards associated with debris flow into a reservoir</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Walder, J.S.; Watts, P.; Waythomas, C.F.</p> <p>2006-01-01</p> <p>Debris-flow <span class="hlt">generated</span> impulse waves (<span class="hlt">tsunamis</span>) pose hazards in lakes, especially those used for hydropower or recreation. We describe a method for assessing <span class="hlt">tsunami</span>-related hazards for the case in which inundation by coherent water waves, rather than chaotic splashing, is of primary concern. The method involves an experimentally based initial condition (<span class="hlt">tsunami</span> source) and a Boussinesq <span class="hlt">model</span> for <span class="hlt">tsunami</span> propagation and inundation. <span class="hlt">Model</span> results are used to create hazard maps that offer guidance for emergency planners and responders. An example application explores <span class="hlt">tsunami</span> hazards associated with potential debris flows entering Baker Lake, a reservoir on the flanks of the Mount Baker volcano in the northwestern United States. ?? 2006 ASCE.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS33B1071W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS33B1071W"><span><span class="hlt">Tsunami</span> Source Identification on the 1867 <span class="hlt">Tsunami</span> Event Based on the Impact Intensity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, T. R.</p> <p>2014-12-01</p> <p>The 1867 Keelung <span class="hlt">tsunami</span> event has drawn significant attention from people in Taiwan. Not only because the location was very close to the 3 nuclear power plants which are only about 20km away from the Taipei city but also because of the ambiguous on the <span class="hlt">tsunami</span> sources. This event is unique in terms of many aspects. First, it was documented on many literatures with many languages and with similar descriptions. Second, the <span class="hlt">tsunami</span> deposit was discovered recently. Based on the literatures, earthquake, 7-meter <span class="hlt">tsunami</span> height, volcanic smoke, and oceanic smoke were observed. Previous studies concluded that this <span class="hlt">tsunami</span> was <span class="hlt">generated</span> by an earthquake with a magnitude around Mw7.0 along the Shanchiao Fault. However, numerical results showed that even a Mw 8.0 earthquake was not able to <span class="hlt">generate</span> a 7-meter <span class="hlt">tsunami</span>. Considering the steep bathymetry and intense volcanic activities along the Keelung coast, one reasonable hypothesis is that different types of <span class="hlt">tsunami</span> sources were existed, such as the submarine landslide or volcanic eruption. In order to confirm this scenario, last year we proposed the <span class="hlt">Tsunami</span> Reverse Tracing Method (TRTM) to find the possible locations of the <span class="hlt">tsunami</span> sources. This method helped us ruling out the impossible far-field <span class="hlt">tsunami</span> sources. However, the near-field sources are still remain unclear. This year, we further developed a new method named 'Impact Intensity Analysis' (IIA). In the IIA method, the study area is divided into a sequence of <span class="hlt">tsunami</span> sources, and the numerical simulations of each source is conducted by COMCOT (Cornell Multi-grid Coupled <span class="hlt">Tsunami</span> <span class="hlt">Model</span>) <span class="hlt">tsunami</span> <span class="hlt">model</span>. After that, the resulting wave height from each source to the study site is collected and plotted. This method successfully helped us to identify the impact factor from the near-field potential sources. The IIA result (Fig. 1) shows that the 1867 <span class="hlt">tsunami</span> event was a multi-source event. A mild <span class="hlt">tsunami</span> was trigged by a Mw7.0 earthquake, and then followed by the submarine</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH31D..05L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH31D..05L"><span>Maritime <span class="hlt">Tsunami</span> Hazard Assessment in California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lynett, P. J.; Borrero, J. C.; Wilson, R. I.; Miller, K. M.</p> <p>2012-12-01</p> <p>The California <span class="hlt">tsunami</span> program in cooperation with NOAA and FEMA has begun implementing a plan to increase awareness of <span class="hlt">tsunami</span> <span class="hlt">generated</span> 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 <span class="hlt">tsunamis</span>. 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 <span class="hlt">models</span> used to <span class="hlt">generate</span> 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 <span class="hlt">tsunami</span> alert notifications. Basin resonance and geometric amplification are two reasonably well understood mechanisms for local magnification of <span class="hlt">tsunami</span> impact in harbors, and are generally the mechanisms investigated when estimating the <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> 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</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1918607V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1918607V"><span>Simulation of the <span class="hlt">Tsunami</span> Resulting from the M 9.2 2004 Sumatra-Andaman Earthquake - Dynamic Rupture vs. Seismic Inversion Source <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vater, Stefan; Behrens, Jörn</p> <p>2017-04-01</p> <p>Simulations of historic <span class="hlt">tsunami</span> events such as the 2004 Sumatra or the 2011 Tohoku event are usually initialized using earthquake sources resulting from inversion of seismic data. Also, other data from ocean buoys etc. is sometimes included in the derivation of the source <span class="hlt">model</span>. The associated <span class="hlt">tsunami</span> event can often be well simulated in this way, and the results show high correlation with measured data. However, it is unclear how the derived source <span class="hlt">model</span> compares to the particular earthquake event. In this study we use the results from dynamic rupture simulations obtained with SeisSol, a software package based on an ADER-DG discretization solving the spontaneous dynamic earthquake rupture problem with high-order accuracy in space and time. The <span class="hlt">tsunami</span> <span class="hlt">model</span> is based on a second-order Runge-Kutta discontinuous Galerkin (RKDG) scheme on triangular grids and features a robust wetting and drying scheme for the simulation of inundation events at the coast. Adaptive mesh refinement enables the efficient computation of large domains, while at the same time it allows for high local resolution and geometric accuracy. The results are compared to measured data and results using earthquake sources based on inversion. With the approach of using the output of actual dynamic rupture simulations, we can estimate the influence of different earthquake parameters. Furthermore, the comparison to other source <span class="hlt">models</span> enables a thorough comparison and validation of important <span class="hlt">tsunami</span> parameters, such as the runup at the coast. This work is part of the ASCETE (Advanced Simulation of Coupled Earthquake and <span class="hlt">Tsunami</span> Events) project, which aims at an improved understanding of the coupling between the earthquake and the <span class="hlt">generated</span> <span class="hlt">tsunami</span> event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5938283','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5938283"><span>Mechanism of the 2015 volcanic <span class="hlt">tsunami</span> earthquake near Torishima, Japan</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Satake, Kenji</p> <p>2018-01-01</p> <p><span class="hlt">Tsunami</span> earthquakes are a group of enigmatic earthquakes <span class="hlt">generating</span> disproportionally large <span class="hlt">tsunamis</span> relative to seismic magnitude. These events occur most typically near deep-sea trenches. <span class="hlt">Tsunami</span> earthquakes occurring approximately every 10 years near Torishima on the Izu-Bonin arc are another example. Seismic and <span class="hlt">tsunami</span> waves from the 2015 event [Mw (moment magnitude) = 5.7] were recorded by an offshore seafloor array of 10 pressure gauges, ~100 km away from the epicenter. We made an array analysis of dispersive <span class="hlt">tsunamis</span> to locate the <span class="hlt">tsunami</span> source within the submarine Smith Caldera. The <span class="hlt">tsunami</span> simulation from a large caldera-floor uplift of ~1.5 m with a small peripheral depression yielded waveforms remarkably similar to the observations. The estimated central uplift, 1.5 m, is ~20 times larger than that inferred from the seismologically determined non–double-couple source. Thus, the <span class="hlt">tsunami</span> observation is not compatible with the published seismic source <span class="hlt">model</span> taken at face value. However, given the indeterminacy of Mzx, Mzy, and M{tensile} of a shallow moment tensor source, it may be possible to find a source mechanism with efficient <span class="hlt">tsunami</span> but inefficient seismic radiation that can satisfactorily explain both the <span class="hlt">tsunami</span> and seismic observations, but this question remains unresolved. PMID:29740604</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29740604','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29740604"><span>Mechanism of the 2015 volcanic <span class="hlt">tsunami</span> earthquake near Torishima, Japan.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fukao, Yoshio; Sandanbata, Osamu; Sugioka, Hiroko; Ito, Aki; Shiobara, Hajime; Watada, Shingo; Satake, Kenji</p> <p>2018-04-01</p> <p><span class="hlt">Tsunami</span> earthquakes are a group of enigmatic earthquakes <span class="hlt">generating</span> disproportionally large <span class="hlt">tsunamis</span> relative to seismic magnitude. These events occur most typically near deep-sea trenches. <span class="hlt">Tsunami</span> earthquakes occurring approximately every 10 years near Torishima on the Izu-Bonin arc are another example. Seismic and <span class="hlt">tsunami</span> waves from the 2015 event [ M w (moment magnitude) = 5.7] were recorded by an offshore seafloor array of 10 pressure gauges, ~100 km away from the epicenter. We made an array analysis of dispersive <span class="hlt">tsunamis</span> to locate the <span class="hlt">tsunami</span> source within the submarine Smith Caldera. The <span class="hlt">tsunami</span> simulation from a large caldera-floor uplift of ~1.5 m with a small peripheral depression yielded waveforms remarkably similar to the observations. The estimated central uplift, 1.5 m, is ~20 times larger than that inferred from the seismologically determined non-double-couple source. Thus, the <span class="hlt">tsunami</span> observation is not compatible with the published seismic source <span class="hlt">model</span> taken at face value. However, given the indeterminacy of M zx , M zy , and M {tensile} of a shallow moment tensor source, it may be possible to find a source mechanism with efficient <span class="hlt">tsunami</span> but inefficient seismic radiation that can satisfactorily explain both the <span class="hlt">tsunami</span> and seismic observations, but this question remains unresolved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH11C..04W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH11C..04W"><span>The FASTER Approach: A New Tool for Calculating Real-Time <span class="hlt">Tsunami</span> Flood Hazards</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilson, R. I.; Cross, A.; Johnson, L.; Miller, K.; Nicolini, T.; Whitmore, P.</p> <p>2014-12-01</p> <p>In the aftermath of the 2010 Chile and 2011 Japan <span class="hlt">tsunamis</span> that struck the California coastline, emergency managers requested that the state <span class="hlt">tsunami</span> program provide more detailed information about the flood potential of distant-source <span class="hlt">tsunamis</span> well ahead of their arrival time. The main issue is that existing <span class="hlt">tsunami</span> evacuation plans call for evacuation of the predetermined "worst-case" <span class="hlt">tsunami</span> evacuation zone (typically at a 30- to 50-foot elevation) during any "Warning" level event; the alternative is to not call an evacuation at all. A solution to provide more detailed information for secondary evacuation zones has been the development of <span class="hlt">tsunami</span> evacuation "playbooks" to plan for <span class="hlt">tsunami</span> scenarios of various sizes and source locations. To determine a recommended level of evacuation during a distant-source <span class="hlt">tsunami</span>, an analytical tool has been developed called the "FASTER" approach, an acronym for factors that influence the <span class="hlt">tsunami</span> flood hazard for a community: Forecast Amplitude, Storm, Tides, Error in forecast, and the Run-up potential. Within the first couple hours after a <span class="hlt">tsunami</span> is <span class="hlt">generated</span>, the National <span class="hlt">Tsunami</span> Warning Center provides <span class="hlt">tsunami</span> forecast amplitudes and arrival times for approximately 60 coastal locations in California. At the same time, the regional NOAA Weather Forecast Offices in the state calculate the forecasted coastal storm and tidal conditions that will influence <span class="hlt">tsunami</span> flooding. Providing added conservatism in calculating <span class="hlt">tsunami</span> flood potential, we include an error factor of 30% for the forecast amplitude, which is based on observed forecast errors during recent events, and a site specific run-up factor which is calculated from the existing state <span class="hlt">tsunami</span> <span class="hlt">modeling</span> database. The factors are added together into a cumulative FASTER flood potential value for the first five hours of <span class="hlt">tsunami</span> activity and used to select the appropriate <span class="hlt">tsunami</span> phase evacuation "playbook" which is provided to each coastal community shortly after the forecast</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43A1826A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43A1826A"><span>Field Investigations and a <span class="hlt">Tsunami</span> <span class="hlt">Modeling</span> for the 1766 Marmara Sea Earthquake, Turkey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aykurt Vardar, H.; Altinok, Y.; Alpar, B.; Unlu, S.; Yalciner, A. C.</p> <p>2016-12-01</p> <p>Turkey is located on one of the world's most hazardous earthquake zones. The northern branch of the North Anatolian fault beneath the Sea of Marmara, where the population is most concentrated, is the most active fault branch at least since late Pliocene. The Sea of Marmara region has been affected by many large tsunamigenic earthquakes; the most destructive ones are 549, 553, 557, 740, 989, 1332, 1343, 1509, 1766, 1894, 1912 and 1999 events. In order to understand and determine the <span class="hlt">tsunami</span> potential and their possible effects along the coasts of this inland sea, detailed documentary, geophysical and numerical <span class="hlt">modelling</span> studies are needed on the past earthquakes and their associated <span class="hlt">tsunamis</span> whose effects are presently unknown.On the northern coast of the Sea of Marmara region, the Kucukcekmece Lagoon has a high potential to trap and preserve <span class="hlt">tsunami</span> deposits. Within the scope of this study, lithological content, composition and sources of organic matters in the lagoon's bottom sediments were studied along a 4.63 m-long piston core recovered from the SE margin of the lagoon. The sedimentary composition and possible sources of the organic matters along the core were analysed and their results were correlated with the historical events on the basis of dating results. Finally, a <span class="hlt">tsunami</span> scenario was tested for May 22nd 1766 Marmara Sea Earthquake by using a widely used <span class="hlt">tsunami</span> simulation <span class="hlt">model</span> called NAMIDANCE. The results show that the candidate <span class="hlt">tsunami</span> deposits at the depths of 180-200 cm below the lagoons bottom were related with the 1766 (May) earthquake. This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University (Project 6384) and by the EU project TRANSFER for coring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23E..07W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23E..07W"><span>Pedestrian flow-path <span class="hlt">modeling</span> to support <span class="hlt">tsunami</span>-evacuation planning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wood, N. J.; Jones, J. M.; Schmidtlein, M.</p> <p>2015-12-01</p> <p>Near-field <span class="hlt">tsunami</span> hazards are credible threats to many coastal communities throughout the world. Along the U.S. Pacific Northwest coast, low-lying areas could be inundated by a series of catastrophic <span class="hlt">tsunamis</span> potentially arriving in a matter of minutes following a Cascadia subduction zone (CSZ) earthquake. We developed a geospatial-<span class="hlt">modeling</span> method for characterizing pedestrian-evacuation flow paths and evacuation basins to support evacuation and relief planning efforts for coastal communities in this region. We demonstrate this approach using the coastal communities of Aberdeen, Hoquiam, and Cosmopolis in southwestern Grays Harbor County, Washington (USA), where previous research suggests approximately 20,500 people (99% of the residents in <span class="hlt">tsunami</span>-hazard zones) will likely have enough time to evacuate before <span class="hlt">tsunami</span>-wave arrival. Geospatial, anisotropic, path distance <span class="hlt">models</span> were developed to map the most efficient pedestrian paths to higher ground from locations within the <span class="hlt">tsunami</span>-hazard zone. This information was then used to identify evacuation basins, outlining neighborhoods sharing a common evacuation pathway to safety. We then estimated the number of people traveling along designated evacuation pathways and arriving at pre-determined safe assembly areas, helping determine shelter demand and relief support (e.g., for elderly individuals or tourists). Finally, we assessed which paths may become inaccessible due to earthquake-induced ground failures, a factor which may impact an individual's success in reaching safe ground. The presentation will include a discussion of the implications of our analysis for developing more comprehensive coastal community <span class="hlt">tsunami</span>-evacuation planning strategies worldwide.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH31C3878R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH31C3878R"><span>Inversion of <span class="hlt">tsunami</span> height using ionospheric observations. The case of the 2012 Haida Gwaii <span class="hlt">tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakoto, V.; Lognonne, P. H.; Rolland, L.</p> <p>2014-12-01</p> <p>Large and moderate <span class="hlt">tsunamis</span> <span class="hlt">generate</span> atmospheric internal gravity waves that are detectable using ionospheric monitoring. Indeed <span class="hlt">tsunamis</span> of height 2cm and more in open ocean were detected with GPS (Rolland et al. 2010). We present a new method to retrieve the <span class="hlt">tsunami</span> height from GPS-derived Total Electron Content observations. We present the case of the Mw 7.8 Haida Gwaii earthquake that occured the 28 october 2012 offshore the Queen Charlotte island near the canadian west coast. This event created a moderate <span class="hlt">tsunami</span> of 4cm offshore the Hawaii archipelago. Equipped with more than 50 receivers it was possible to image the <span class="hlt">tsunami</span>-induced ionospheric perturbation. First, our forward <span class="hlt">model</span> leading to the TEC perturbation follows three steps : (1) 3D <span class="hlt">modeling</span> of the neutral atmosphere perturbation by summation of <span class="hlt">tsunami</span>-induced gravity waves normal modes. (2) Coupling of the neutral atmosphere perturbation with the ionosphere to retrieve the electron density perturbation. (3) Integration of the electron density perturbation along each satellite-station ray path. Then we compare this results to the data acquired by the Hawaiian GPS network. Finally, we examine the possibility to invert the TEC data in order to retrieve the <span class="hlt">tsunami</span> height and waveform. For this we investigate the link between the height of <span class="hlt">tsunamis</span> and the perturbed TEC in the ionosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018SedG..364..319C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018SedG..364..319C"><span>Geological evidence and sediment transport <span class="hlt">modelling</span> for the 1946 and 1960 <span class="hlt">tsunamis</span> in Shinmachi, Hilo, Hawaii</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chagué, Catherine; Sugawara, Daisuke; Goto, Kazuhisa; Goff, James; Dudley, Walter; Gadd, Patricia</p> <p>2018-02-01</p> <p>The Japanese community of Shinmachi, established on low-lying land between downtown Hilo and Waiakea, Hawaii, was obliterated by the 1946 Aleutian <span class="hlt">tsunami</span> but was rebuilt, only to be destroyed again by the 1960 Chilean <span class="hlt">tsunami</span>. The aim of this study was to find out if any geological evidence of these well documented events had been preserved in the sedimentary record in Wailoa River State Park, which replaced Shinmachi after the 1960 <span class="hlt">tsunami</span>. This was achieved by collecting cores in the park and performing sedimentological, chronological and geochemical analyses, the latter also processed by principal component analysis. Sediment transport <span class="hlt">modelling</span> was carried out for both <span class="hlt">tsunamis</span>, to infer the source of the sediment and areas of deposition on land. The field survey revealed two distinct units within peat and soil, a thin lower unit composed of weathered basalt fragments within mud (Unit 1) and an upper unit dominated by fine volcanic sand within fine silt exhibiting subtle upward fining and coarsening (Unit 2, consisting of Unit 2A and Unit 2B), although these two anomalous units only occur on the western shore of Waiakea Mill Pond. Analysis with an ITRAX core scanner shows that Unit 1 is characterised by high Mn, Fe, Rb, La and Ce counts, combined with elevated magnetic susceptibility. Based on its chemical and sedimentological characteristics, Unit 1 is attributed to a flood event in Wailoa River that occurred around 1520-1660 CE, most probably as a result of a tropical storm. The sharp lower contact of Unit 2 coincides with the appearance of arsenic, contemporaneous with an increase in Ca, Sr, Si, Ti, K, Zr, Mn, Fe, La and Ce. In this study, As is used as a chronological and source material marker, as it is known to have been released into Wailoa River Estuary and Waiakea Mill Pond by the Canec factory between 1932 and 1963. Thus, not only the chemical and sedimentological evidence but also sediment transport <span class="hlt">modelling</span>, corroborating the historical record</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S31E..06B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S31E..06B"><span>Uncertainty Estimation in <span class="hlt">Tsunami</span> Initial Condition From Rapid Bayesian Finite Fault <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Benavente, R. F.; Dettmer, J.; Cummins, P. R.; Urrutia, A.; Cienfuegos, R.</p> <p>2017-12-01</p> <p>It is well known that kinematic rupture <span class="hlt">models</span> for a given earthquake can present discrepancies even when similar datasets are employed in the inversion process. While quantifying this variability can be critical when making early estimates of the earthquake and triggered <span class="hlt">tsunami</span> impact, "most likely <span class="hlt">models</span>" are normally used for this purpose. In this work, we quantify the uncertainty of the <span class="hlt">tsunami</span> initial condition for the great Illapel earthquake (Mw = 8.3, 2015, Chile). We focus on utilizing data and inversion methods that are suitable to rapid source characterization yet provide meaningful and robust results. Rupture <span class="hlt">models</span> from teleseismic body and surface waves as well as W-phase are derived and accompanied by Bayesian uncertainty estimates from linearized inversion under positivity constraints. We show that robust and consistent features about the rupture kinematics appear when working within this probabilistic framework. Moreover, by using static dislocation theory, we translate the probabilistic slip distributions into seafloor deformation which we interpret as a <span class="hlt">tsunami</span> initial condition. After considering uncertainty, our probabilistic seafloor deformation <span class="hlt">models</span> obtained from different data types appear consistent with each other providing meaningful results. We also show that selecting just a single "representative" solution from the ensemble of initial conditions for <span class="hlt">tsunami</span> propagation may lead to overestimating information content in the data. Our results suggest that rapid, probabilistic rupture <span class="hlt">models</span> can play a significant role during emergency response by providing robust information about the extent of the disaster.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70037131','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70037131"><span><span class="hlt">Tsunamis</span> and splay fault dynamics</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wendt, J.; Oglesby, D.D.; Geist, E.L.</p> <p>2009-01-01</p> <p>The geometry of a fault system can have significant effects on <span class="hlt">tsunami</span> <span class="hlt">generation</span>, but most <span class="hlt">tsunami</span> <span class="hlt">models</span> to date have not investigated the dynamic processes that determine which path rupture will take in a complex fault system. To gain insight into this problem, we use the 3D finite element method to <span class="hlt">model</span> the dynamics of a plate boundary/splay fault system. We use the resulting ground deformation as a time-dependent boundary condition for a 2D shallow-water hydrodynamic <span class="hlt">tsunami</span> calculation. We find that if me stress distribution is homogeneous, rupture remains on the plate boundary thrust. When a barrier is introduced along the strike of the plate boundary thrust, rupture propagates to the splay faults, and produces a significantly larger <span class="hlt">tsunami</span> man in the homogeneous case. The results have implications for the dynamics of megathrust earthquakes, and also suggest mat dynamic earthquake <span class="hlt">modeling</span> may be a useful tool in <span class="hlt">tsunami</span> researcn. Copyright 2009 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.174.3043D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.174.3043D"><span>Challenges in Defining <span class="hlt">Tsunami</span> Wave Heights</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dunbar, Paula; Mungov, George; Sweeney, Aaron; Stroker, Kelly; Arcos, Nicolas</p> <p>2017-08-01</p> <p>The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global <span class="hlt">tsunami</span> archive consisting of the historical <span class="hlt">tsunami</span> database, imagery, and raw and processed water level data. The historical <span class="hlt">tsunami</span> database incorporates, where available, maximum wave heights for each coastal tide gauge and deep-ocean buoy that recorded a <span class="hlt">tsunami</span> signal. These data are important because they are used for <span class="hlt">tsunami</span> hazard assessment, <span class="hlt">model</span> calibration, validation, and forecast and warning. There have been ongoing discussions in the <span class="hlt">tsunami</span> community about the correct way to measure and report these wave heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum wave height. On September 16, 2015, an 8.3 M w earthquake located 48 km west of Illapel, Chile <span class="hlt">generated</span> a <span class="hlt">tsunami</span> that was observed all over the Pacific region. We processed the time-series water level data for 57 coastal tide gauges that recorded this <span class="hlt">tsunami</span> and compared the maximum wave heights determined from different definitions. We also compared the maximum wave heights from the NCEI-processed data with the heights reported by the NOAA <span class="hlt">Tsunami</span> Warning Centers. We found that in the near field different methods of determining the maximum <span class="hlt">tsunami</span> wave heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were <20 cm. For this event, the maximum <span class="hlt">tsunami</span> wave heights determined by either definition (maximum peak or amplitude) would have validated the forecasts issued by the NOAA <span class="hlt">Tsunami</span> Warning Centers. Since there is currently only one field in the NCEI historical <span class="hlt">tsunami</span> database to store the maximum <span class="hlt">tsunami</span> wave height for each tide gauge and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH11C..07B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH11C..07B"><span>The First Real-Time <span class="hlt">Tsunami</span> Animation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Becker, N. C.; Wang, D.; McCreery, C.; Weinstein, S.; Ward, B.</p> <p>2014-12-01</p> <p>For the first time a U.S. <span class="hlt">tsunami</span> warning center created and issued a <span class="hlt">tsunami</span> forecast <span class="hlt">model</span> animation while the <span class="hlt">tsunami</span> was still crossing an ocean. Pacific <span class="hlt">Tsunami</span> Warning Center (PTWC) scientists had predicted they would have this ability (Becker et al., 2012) with their RIFT forecast <span class="hlt">model</span> (Wang et al., 2009) by using rapidly-determined W-phase centroid-moment tensor earthquake focal mechanisms as <span class="hlt">tsunami</span> sources in the RIFT <span class="hlt">model</span> (Wang et al., 2012). PTWC then acquired its own YouTube channel in 2013 for its outreach efforts that showed animations of historic <span class="hlt">tsunamis</span> (Becker et al., 2013), but could also be a platform for sharing future <span class="hlt">tsunami</span> animations. The 8.2 Mw earthquake of 1 April 2014 prompted PTWC to issue official warnings for a dangerous <span class="hlt">tsunami</span> in Chile, Peru and Ecuador. PTWC ended these warnings five hours later, then issued its new <span class="hlt">tsunami</span> marine hazard product (i.e., no coastal evacuations) for the State of Hawaii. With the international warning canceled but with a domestic hazard still present PTWC <span class="hlt">generated</span> a forecast <span class="hlt">model</span> animation and uploaded it to its YouTube channel six hours before the arrival of the first waves in Hawaii. PTWC also gave copies of this animation to television reporters who in turn passed it on to their national broadcast networks. PTWC then created a version for NOAA's Science on a Sphere system so it could be shown on these exhibits as the <span class="hlt">tsunami</span> was still crossing the Pacific Ocean. While it is difficult to determine how many people saw this animation since local, national, and international news networks showed it in their broadcasts, PTWC's YouTube channel provides some statistics. As of 1 August 2014 this animation has garnered more than 650,000 views. Previous animations, typically released during significant anniversaries, rarely get more than 10,000 views, and even then only when external websites share them. Clearly there is a high demand for a <span class="hlt">tsunami</span> graphic that shows both the speed and the severity of a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNH21D1528Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNH21D1528Q"><span><span class="hlt">Tsunami</span> hazard assessment in La Reunion and Mayotte Islands in the Indian Ocean : detailed <span class="hlt">modeling</span> of <span class="hlt">tsunami</span> impacts for the PREPARTOI project</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quentel, E.; Loevenbruck, A.; Sahal, A.; Lavigne, F.</p> <p>2011-12-01</p> <p>Significant <span class="hlt">tsunamis</span> have often affected the southwest Indian Ocean. The scientific project PREPARTOI (Prévention et REcherche pour l'Atténuation du Risque <span class="hlt">Tsunami</span> dans l'Océan Indien), partly founded by the MAIF foundation, aims at assessing the <span class="hlt">tsunami</span> risk on both french islands of this region, La Réunion and Mayotte. Further purpose of this project is the detailed hazard and vulnerability study for specific places of these islands, selected according to their environmental and human issues and observed impacts of past <span class="hlt">tsunamis</span>. <span class="hlt">Tsunami</span> hazard in this region, recently highlighted by major events in the southwest Indian Ocean, has never been thoroughly evaluated. Our study, within the PREPARTOI project, contributes to fill in this lack. It aims at examining transoceanic <span class="hlt">tsunami</span> hazard related to earthquakes by <span class="hlt">modeling</span> the scenarios of major historical events. We consider earthquakes with magnitude greater than Mw 7.7 located on the Sumatra (1833, 2004, 2010), Java (2006) and Makran (1945) subduction zones. First, our simulations allow us to compare the <span class="hlt">tsunami</span> impact at regional scale according to the seismic sources; we thus identify earthquakes locations which most affect the islands and describe the impact distribution along their coastline. In general, we note that, for the same magnitude, events coming from the southern part of Sumatra subduction zone induce a larger impact than the north events. The studied <span class="hlt">tsunamis</span> initiated along the Java and Makran subduction zones have limited effects on both French islands. Then, detailed <span class="hlt">models</span> for the selected sites are performed based on high resolution bathymetric and topographic data; they provide estimations of the water currents, the water heights and the potential inundations. When available, field measurements and maregraphic records allow testing our <span class="hlt">models</span>. Arrival time, amplitude of the first wave and impact on the tide gauge time series are well reproduced. <span class="hlt">Models</span> are consistent with the observations</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PApGe.173.3823L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PApGe.173.3823L"><span>Possible worst-case <span class="hlt">tsunami</span> scenarios around the Marmara Sea from combined earthquake and landslide sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Latcharote, Panon; Suppasri, Anawat; Imamura, Fumihiko; Aytore, Betul; Yalciner, Ahmet Cevdet</p> <p>2016-12-01</p> <p>This study evaluates <span class="hlt">tsunami</span> hazards in the Marmara Sea from possible worst-case <span class="hlt">tsunami</span> scenarios that are from submarine earthquakes and landslides. In terms of fault-<span class="hlt">generated</span> <span class="hlt">tsunamis</span>, seismic ruptures can propagate along the North Anatolian Fault (NAF), which has produced historical <span class="hlt">tsunamis</span> in the Marmara Sea. Based on the past studies, which consider fault-<span class="hlt">generated</span> <span class="hlt">tsunamis</span> and landslide-<span class="hlt">generated</span> <span class="hlt">tsunamis</span> individually, future scenarios are expected to <span class="hlt">generate</span> <span class="hlt">tsunamis</span>, and submarine landslides could be triggered by seismic motion. In addition to these past studies, numerical <span class="hlt">modeling</span> has been applied to <span class="hlt">tsunami</span> <span class="hlt">generation</span> and propagation from combined earthquake and landslide sources. In this study, <span class="hlt">tsunami</span> hazards are evaluated from both individual and combined cases of submarine earthquakes and landslides through numerical <span class="hlt">tsunami</span> simulations with a grid size of 90 m for bathymetry and topography data for the entire Marmara Sea region and validated with historical observations from the 1509 and 1894 earthquakes. This study implements TUNAMI <span class="hlt">model</span> with a two-layer <span class="hlt">model</span> to conduct numerical <span class="hlt">tsunami</span> simulations, and the numerical results show that the maximum <span class="hlt">tsunami</span> height could reach 4.0 m along Istanbul shores for a full submarine rupture of the NAF, with a fault slip of 5.0 m in the eastern and western basins of the Marmara Sea. The maximum <span class="hlt">tsunami</span> height for landslide-<span class="hlt">generated</span> <span class="hlt">tsunamis</span> from small, medium, and large of initial landslide volumes (0.15, 0.6, and 1.5 km3, respectively) could reach 3.5, 6.0, and 8.0 m, respectively, along Istanbul shores. Possible <span class="hlt">tsunamis</span> from submarine landslides could be significantly higher than those from earthquakes, depending on the landslide volume significantly. These combined earthquake and landslide sources only result in higher <span class="hlt">tsunami</span> amplitudes for small volumes significantly because of amplification within the same <span class="hlt">tsunami</span> amplitude scale (3.0-4.0 m). Waveforms from all the coasts around the Marmara Sea</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1212827Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1212827Z"><span>Statistical Analysis of <span class="hlt">Tsunami</span> Variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zolezzi, Francesca; Del Giudice, Tania; Traverso, Chiara; Valfrè, Giulio; Poggi, Pamela; Parker, Eric J.</p> <p>2010-05-01</p> <p>The purpose of this paper was to investigate statistical variability of seismically <span class="hlt">generated</span> <span class="hlt">tsunami</span> impact. The specific goal of the work was to evaluate the variability in <span class="hlt">tsunami</span> wave run-up due to uncertainty in fault rupture parameters (source effects) and to the effects of local bathymetry at an individual location (site effects). This knowledge is critical to development of methodologies for probabilistic <span class="hlt">tsunami</span> hazard assessment. Two types of variability were considered: • Inter-event; • Intra-event. Generally, inter-event variability refers to the differences of <span class="hlt">tsunami</span> run-up at a given location for a number of different earthquake events. The focus of the current study was to evaluate the variability of <span class="hlt">tsunami</span> run-up at a given point for a given magnitude earthquake. In this case, the variability is expected to arise from lack of knowledge regarding the specific details of the fault rupture "source" parameters. As sufficient field observations are not available to resolve this question, numerical <span class="hlt">modelling</span> was used to <span class="hlt">generate</span> run-up data. A scenario magnitude 8 earthquake in the Hellenic Arc was <span class="hlt">modelled</span>. This is similar to the event thought to have caused the infamous 1303 <span class="hlt">tsunami</span>. The <span class="hlt">tsunami</span> wave run-up was computed at 4020 locations along the Egyptian coast between longitudes 28.7° E and 33.8° E. Specific source parameters (e.g. fault rupture length and displacement) were varied, and the effects on wave height were determined. A Monte Carlo approach considering the statistical distribution of the underlying parameters was used to evaluate the variability in wave height at locations along the coast. The results were evaluated in terms of the coefficient of variation of the simulated wave run-up (standard deviation divided by mean value) for each location. The coefficient of variation along the coast was between 0.14 and 3.11, with an average value of 0.67. The variation was higher in areas of irregular coast. This level of variability is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22307896-identification-earthquakes-generate-tsunamis-java-nusa-tenggara-using-rupture-duration-analysis','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22307896-identification-earthquakes-generate-tsunamis-java-nusa-tenggara-using-rupture-duration-analysis"><span>Identification of earthquakes that <span class="hlt">generate</span> <span class="hlt">tsunamis</span> in Java and Nusa Tenggara using rupture duration analysis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pribadi, S., E-mail: sugengpribadimsc@gmail.com; Puspito, N. T.; Yudistira, T.</p> <p></p> <p>Java and Nusa Tenggara are the tectonically active of Sunda arc. This study discuss the rupture duration as a manifestation of the power of earthquake-<span class="hlt">generated</span> <span class="hlt">tsunami</span>. We use the teleseismic (30° - 90°) body waves with high-frequency energy Seismometer is from IRIS network as amount 206 broadband units. We applied the Butterworth high bandpass (1 - 2 Hz) filtered. The arrival and travel times started from wave phase of P - PP which based on Jeffrey Bullens table with TauP program. The results are that the June 2, 1994 Banyuwangi and the July 17, 2006 Pangandaran earthquakes identified as tsunamimore » earthquakes with long rupture duration (To > 100 second), medium magnitude (7.6 < Mw < 7.9) and located near the trench. The others are 4 tsunamigenic earthquakes and 3 inland earthquakes with short rupture duration start from To > 50 second which depend on its magnitude. Those events are located far from the trench.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH13A3720C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH13A3720C"><span>A rapid estimation of <span class="hlt">tsunami</span> run-up based on finite fault <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Campos, J.; Fuentes, M. A.; Hayes, G. P.; Barrientos, S. E.; Riquelme, S.</p> <p>2014-12-01</p> <p>Many efforts have been made to estimate the maximum run-up height of <span class="hlt">tsunamis</span> associated with large earthquakes. This is a difficult task, because of the time it takes to construct a <span class="hlt">tsunami</span> <span class="hlt">model</span> using real time data from the source. It is possible to construct a database of potential seismic sources and their corresponding <span class="hlt">tsunami</span> a priori. However, such <span class="hlt">models</span> are generally based on uniform slip distributions and thus oversimplify our knowledge of the earthquake source. Instead, we can use finite fault <span class="hlt">models</span> of earthquakes to give a more accurate prediction of the <span class="hlt">tsunami</span> run-up. Here we show how to accurately predict <span class="hlt">tsunami</span> run-up from any seismic source <span class="hlt">model</span> using an analytic solution found by Fuentes et al, 2013 that was especially calculated for zones with a very well defined strike, i.e, Chile, Japan, Alaska, etc. The main idea of this work is to produce a tool for emergency response, trading off accuracy for quickness. Our solutions for three large earthquakes are promising. Here we compute <span class="hlt">models</span> of the run-up for the 2010 Mw 8.8 Maule Earthquake, the 2011 Mw 9.0 Tohoku Earthquake, and the recent 2014 Mw 8.2 Iquique Earthquake. Our maximum rup-up predictions are consistent with measurements made inland after each event, with a peak of 15 to 20 m for Maule, 40 m for Tohoku, and 2,1 m for the Iquique earthquake. Considering recent advances made in the analysis of real time GPS data and the ability to rapidly resolve the finiteness of a large earthquake close to existing GPS networks, it will be possible in the near future to perform these calculations within the first five minutes after the occurrence of any such event. Such calculations will thus provide more accurate run-up information than is otherwise available from existing uniform-slip seismic source databases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PApGe.173.3955A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PApGe.173.3955A"><span>A Pilot <span class="hlt">Tsunami</span> Inundation Forecast System for Australia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allen, Stewart C. R.; Greenslade, Diana J. M.</p> <p>2016-12-01</p> <p>The Joint Australian <span class="hlt">Tsunami</span> Warning Centre (JATWC) provides a <span class="hlt">tsunami</span> warning service for Australia. Warnings are currently issued according to a technique that does not include explicit <span class="hlt">modelling</span> at the coastline, including any potential coastal inundation. This paper investigates the feasibility of developing and implementing <span class="hlt">tsunami</span> inundation <span class="hlt">modelling</span> as part of the JATWC warning system. An inundation <span class="hlt">model</span> was developed for a site in Southeast Australia, on the basis of the availability of bathymetric and topographic data and observations of past <span class="hlt">tsunamis</span>. The <span class="hlt">model</span> was forced using data from T2, the operational deep-water <span class="hlt">tsunami</span> scenario database currently used for <span class="hlt">generating</span> warnings. The <span class="hlt">model</span> was evaluated not only for its accuracy but also for its computational speed, particularly with respect to operational applications. Limitations of the proposed forecast processes in the Australian context and areas requiring future improvement are discussed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH41A1748M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH41A1748M"><span>Advancing our understanding of the onshore propagation of <span class="hlt">tsunami</span> bores over rough surfaces through numerical <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marras, S.; Suckale, J.; Eguzkitza, B.; Houzeaux, G.; Vázquez, M.; Lesage, A. C.</p> <p>2016-12-01</p> <p>The propagation of <span class="hlt">tsunamis</span> in the open ocean has been studied in detail with many excellent numerical approaches available to researchers. Our understanding of the processes that govern the onshore propagation of <span class="hlt">tsunamis</span> is less advanced. Yet, the reach of <span class="hlt">tsunamis</span> on land is an important predictor of the damage associated with a given event, highlighting the need to investigate the factors that govern <span class="hlt">tsunami</span> propagation onshore. In this study, we specifically focus on understanding the effect of bottom roughness at a variety of scales. The term roughness is to be understood broadly, as it represents scales ranging from small features like rocks, to vegetation, up to the size of larger structures and topography. In this poster, we link applied mathematics, computational fluid dynamics, and <span class="hlt">tsunami</span> physics to analyze the small scales features of coastal hydrodynamics and the effect of roughness on the motion of <span class="hlt">tsunamis</span> as they run up a sloping beach and propagate inland. We solve the three-dimensional Navier-Stokes equations of incompressible flows with free surface, which is tracked by a level set function in combination with an accurate re-distancing scheme. We discretize the equations via linear finite elements for space approximation and fully implicit time integration. Stabilization is achieved via the variational multiscale method whereas the subgrid scales for our large eddy simulations are <span class="hlt">modeled</span> using a dynamically adaptive Smagorinsky eddy viscosity. As the geometrical characteristics of roughness in this study vary greatly across different scales, we implement a scale-dependent representation of the roughness elements. We <span class="hlt">model</span> the smallest sub-grid scale roughness features by the use of a properly defined law of the wall. Furthermore, we utilize a Manning formula to compute the shear stress at the boundary. As the geometrical scales become larger, we resolve the geometry explicitly and compute the effective volume drag introduced by large scale</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH31A0199U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH31A0199U"><span>Using Point Clouds <span class="hlt">Generated</span> from Unmanned Aerial Vehicles Imagery Processed with Structure from Motion to Address <span class="hlt">Tsunami</span> vs Storm Wave Boulder Deposition in Watu Karung, Indonesia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Uribe, A. T.; Bunds, M. P.; Andreini, J.; Horns, D. M.; Harris, R. A.; Prasetyadi, C.; Yulianto, E.; Putra, P. S.</p> <p>2017-12-01</p> <p><span class="hlt">Tsunamis</span> pose a major hazard to coastal communities along the south coast of much of Indonesia due its location on the Australian-Sunda arc. Furthermore, <span class="hlt">tsunamis</span> and high-energy wave events are the principal drivers of geomorphic change in the area and it is difficult to distinguish the effects of each. A potentially useful indicator of past <span class="hlt">tsunami</span> activity is coastal imbricated boulder deposits. To address whether an imbricated boulder deposit located on a beach in Watu Karung (Java, Indonesia) could have been formed by non-<span class="hlt">tsunami</span> wave activity and to investigate coastal geomorphic change, we <span class="hlt">generated</span> three pairs of digital surface <span class="hlt">models</span> (DSMs) over an approximately one year period using photographs taken from a small unmanned aerial vehicle and structure-from-motion photogrammetry. The first two DSMs were made from photographs taken on 7/30-31/2016 and 8/2/2016, immediately before and after a significant 4.2 m swell struck the beach during a +2.5 m spring high tide. The third DSM pair was made from imagery collected 7/12/2017. Each pair of DSMs consists of a 1 cm pixel DSM of the boulder deposit and a 4 cm DSM of the larger beach area that surrounds the boulders. In addition, prior to the 2016 wave event 21 boulders up to 75 kg were marked and hand-placed shoreward of the boulder deposit; their movement was tracked with RTK GPS measurements. In the 2016 wave event, every hand-placed boulder moved, with an average displacement of 27.6 m. At the same time, approximately 20 of 650 naturally - occurring boulders, up to 2 m in length, moved more than 10 cm and up to 5.6 m. Between 2016 and 2017, approximately 300 of 650 naturally - occurring boulders with an average length of 1.6 m moved varying distances of at least 10 cm and up to 30 m. In addition, changes in beach sand volume occurred in ten 25 m2 localized zones on the beach with an average volume change of approximately 65 m2. Changes in both boulder position and sand volume occurred during the 2016 to 2017</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1213898B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1213898B"><span>New <span class="hlt">Tsunami</span> Inundation Maps for California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barberopoulou, Aggeliki; Borrero, Jose; Uslu, Burak; Kanoglu, Utku; Synolakis, Costas</p> <p>2010-05-01</p> <p>California is the first US State to complete its <span class="hlt">tsunami</span> inundation mapping. A new <span class="hlt">generation</span> of <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> farfield and nearfield sources and use the best available bathymetric and topographic data for <span class="hlt">modelling</span>. The need for new <span class="hlt">tsunami</span> maps for California became clear since Synolakis et al (1998) described how inundation projections derived with inundation <span class="hlt">models</span> that fully calculate the wave evolution over dry land can be as high as twice the values predicted with earlier threshold <span class="hlt">models</span>, for <span class="hlt">tsunamis</span> originating from tectonic source. Since the 1998 Papua New Guinea <span class="hlt">tsunami</span> when the hazard from offshore submarine landslides was better understood (Bardet et al, 2003), the State of California funded the development of the first <span class="hlt">generation</span> 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 <span class="hlt">generation</span> of maps incorporates local and distant scenarios. The partnership between the <span class="hlt">Tsunami</span> 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 <span class="hlt">model</span>. They are a significant improvement over earlier map <span class="hlt">generations</span>. As part of a continuous improvement in response, mitigation and planning and community education, the California inundation maps can contribute in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JVGR..347..221G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JVGR..347..221G"><span><span class="hlt">Tsunami</span> deposits associated with the 7.3 ka caldera-forming eruption of the Kikai Caldera, insights for <span class="hlt">tsunami</span> <span class="hlt">generation</span> during submarine caldera-forming eruptions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geshi, Nobuo; Maeno, Fukashi; Nakagawa, Shojiro; Naruo, Hideto; Kobayashi, Tetsuo</p> <p>2017-11-01</p> <p>Timing and mechanism of volcanic <span class="hlt">tsunamis</span> will be a key to understand the dynamics of large-scale submarine explosive volcanism. <span class="hlt">Tsunami</span> deposits associated with the VEI 7 eruption of the Kikai Caldera at 7.3 ka are found in the Yakushima and Kuchinoerabujima Islands, 40 km south -southeast of the caldera rim. The <span class="hlt">tsunami</span> deposits distribute along the rivers in their northern coast up to 4.5 km from the river exit and up to 50 m above the present sea level. The <span class="hlt">tsunami</span> deposits in the Yakushima area consist of pumice-bearing gravels in the lower part of the section (Unit I) and pumiceous conglomerate in the upper part (Unit II). The presence of rounded pebbles of sedimentary rocks, which characterize the beach deposit, indicates a run-up current from the coastal area. The rip-up clasts of the underlying paleosol in Unit I show strong erosion during the invasion of <span class="hlt">tsunami</span>. Compositional similarity between the pumices in the <span class="hlt">tsunami</span> deposit and the juvenile materials erupted in the early phase of the Akahoya eruption indicates the formation of <span class="hlt">tsunami</span> deposit during the early phase of the eruption, which produced the initial Plinian pumice fall and the lower half of the Koya pyroclastic flow. Presence of the dense volcanic components (obsidians and lava fragments) besides pumices in the <span class="hlt">tsunami</span> deposit supports that they were carried by the Koya pyroclastic flow, and not the pumices floating on the sea surface. Sequential relationship between the Koya pyroclastic flow and the <span class="hlt">tsunami</span> suggests that the emplacement of the pyroclastic flow into the sea surrounding the caldera is the most probable mechanism of the <span class="hlt">tsunami</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70193626','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70193626"><span><span class="hlt">Tsunami-generated</span> sediment wave channels at Lake Tahoe, California-Nevada, USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Moore, James G.; Schweickert, Richard A.; Kitts, Christopher A.</p> <p>2014-01-01</p> <p>A gigantic ∼12 km3 landslide detached from the west wall of Lake Tahoe (California-Nevada, USA), and slid 15 km east across the lake. The splash, or <span class="hlt">tsunami</span>, from this landslide eroded Tioga-age moraines dated as 21 ka. Lake-bottom short piston cores recovered sediment as old as 12 ka that did not reach landslide deposits, thereby constraining the landslide age as 21–12 ka.Movement of the landslide splashed copious water onto the countryside and lowered the lake level ∼10 m. The sheets of water that washed back into the lake dumped their sediment load at the lowered shoreline, producing deltas that merged into delta terraces. During rapid growth, these unstable delta terraces collapsed, disaggregated, and fed turbidity currents that <span class="hlt">generated</span> 15 subaqueous sediment wave channel systems that ring the lake and descend to the lake floor at 500 m depth. Sheets of water commonly more than 2 km wide at the shoreline fed these systems. Channels of the systems contain sediment waves (giant ripple marks) with maximum wavelengths of 400 m. The lower depositional aprons of the system are surfaced by sediment waves with maximum wavelengths of 300 m.A remarkably similar, though smaller, contemporary sediment wave channel system operates at the mouth of the Squamish River in British Columbia. The system is <span class="hlt">generated</span> by turbidity currents that are fed by repeated growth and collapse of the active river delta. The Tahoe splash-induced backwash was briefly equivalent to more than 15 Squamish Rivers in full flood and would have decimated life in low-lying areas of the Tahoe region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH43A0183K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH43A0183K"><span><span class="hlt">Tsunami</span>-Induced Nearshore Hydrodynamic <span class="hlt">Modeling</span> using a 3D VOF Method: A Gulf of Mexico Case Study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kian, R.; Horrillo, J. J.; Fang, N. Z.</p> <p>2017-12-01</p> <p>Long-term morphology changes can be interrupted by extreme events such as hurricanes and <span class="hlt">tsunamis</span>. In particular, the impact of <span class="hlt">tsunamis</span> on coastal erosion and accretion patterns is presently not well understood. In order to understand the sediment movement during coastal <span class="hlt">tsunami</span> impact a numerical sediment transport <span class="hlt">model</span> is added to a 3D VOF <span class="hlt">model</span>. This <span class="hlt">model</span> allows for spatially varying bottom sediment characteristics and entails functions for entrainment, bedload, and suspended load transport. As a case study, a Gulf of Mexico (GOM) coastal study site is selected to investigate the effect of a landslide-<span class="hlt">tsunami</span> on the coastal morphology. The GOM is recognized as a vast and productive body of water with great ecologic and economic value. The morphodynamic response of the nearshore environment to the <span class="hlt">tsunami</span> hydrodynamic forcing is influenced by many factors including bathymetry, topography, <span class="hlt">tsunami</span> wave and current magnitude, and the characteristics of the local bottom substrate. The 3D <span class="hlt">model</span> addition can account for all these factors. Finally, necessary strategies for reduction of the potential <span class="hlt">tsunami</span> impact and management of the morphological changes are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23A1850G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23A1850G"><span>Shallow water <span class="hlt">models</span> as tool for <span class="hlt">tsunami</span> current predictions in ports and harbors. Validation with Tohoku 2011 field data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gonzalez Vida, J. M., Sr.; Macias Sanchez, J.; Castro, M. J.; Ortega, S.</p> <p>2015-12-01</p> <p><span class="hlt">Model</span> ability to compute and predict <span class="hlt">tsunami</span> flow velocities is of importance in risk assessment and hazard mitigation. Substantial damage can be produced by high velocity flows, particularly in harbors and bays, even when the wave height is small. Besides, an accurate simulation of <span class="hlt">tsunami</span> flow velocities and accelerations is fundamental for advancing in the study of <span class="hlt">tsunami</span> sediment transport. These considerations made the National <span class="hlt">Tsunami</span> Hazard Mitigation Program (NTHMP) proposing a benchmark exercise focused on <span class="hlt">modeling</span> and simulating <span class="hlt">tsunami</span> currents. Until recently, few direct measurements of <span class="hlt">tsunami</span> velocities were available to compare and to validate <span class="hlt">model</span> results. After Tohoku 2011 many current meters measurement were made, mainly in harbors and channels. In this work we present a part of the contribution made by the EDANYA group from the University of Malaga to the NTHMP workshop organized at Portland (USA), 9-10 of February 2015. We have selected three out of the five proposed benchmark problems. Two of them consist in real observed data from the Tohoku 2011 event, one at Hilo Habour (Hawaii) and the other at Tauranga Bay (New Zealand). The third one consists in laboratory experimental data for the inundation of Seaside City in Oregon. For this <span class="hlt">model</span> validation the <span class="hlt">Tsunami</span>-HySEA <span class="hlt">model</span>, developed by EDANYA group, was used. The overall conclusion that we could extract from this validation exercise was that the <span class="hlt">Tsunami</span>-HySEA <span class="hlt">model</span> performed well in all benchmark problems proposed. The greater spatial variability in <span class="hlt">tsunami</span> velocity than wave height makes it more difficult its precise numerical representation. The larger variability in velocities is likely a result of the behaviour of the flow as it is channelized and as it flows around bathymetric highs and structures. In the other hand wave height do not respond as strongly to chanelized flow as current velocity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170000319','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170000319"><span><span class="hlt">Tsunami</span> <span class="hlt">Generation</span> from Asteroid Airburst and Ocean Impact and Van Dorn Effect</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Robertson, Darrel</p> <p>2016-01-01</p> <p>Airburst - In the simulations explored energy from the airburst couples very weakly with the water making <span class="hlt">tsunami</span> dangerous over a shorter distance than the blast for asteroid sizes up to the maximum expected size that will still airburst (approx.250MT). Future areas of investigation: - Low entry angle airbursts create more cylindrical blasts and might couple more efficiently - Bursts very close to the ground will increase coupling - Inclusion of thermosphere (>80km altitude) may show some plume collapse effects over a large area although with much less pressure center dot Ocean Impact - Asteroid creates large cavity in ocean. Cavity backfills creating central jet. Oscillation between the cavity and jet sends out <span class="hlt">tsunami</span> wave packet. - For deep ocean impact waves are deep water waves (Phase speed = 2x Group speed) - If the <span class="hlt">tsunami</span> propagation and inundation calculations are correct for the small (<250MT) asteroids in these simulations where they impact deep ocean basins, the resulting <span class="hlt">tsunami</span> is not a significant hazard unless particularly close to vulnerable communities. Future work: - Shallow ocean impact. - Effect of continental shelf and beach profiles - <span class="hlt">Tsunami</span> vs. blast damage radii for impacts close to populated areas - Larger asteroids below presumed threshold of global effects (Ø200 - 800m).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S21A4392H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S21A4392H"><span>Open Source Seismic Software in NOAA's Next <span class="hlt">Generation</span> <span class="hlt">Tsunami</span> Warning System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hellman, S. B.; Baker, B. I.; Hagerty, M. T.; Leifer, J. M.; Lisowski, S.; Thies, D. A.; Donnelly, B. K.; Griffith, F. P.</p> <p>2014-12-01</p> <p>The <span class="hlt">Tsunami</span> Information technology Modernization (TIM) is a project spearheaded by National Oceanic and Atmospheric Administration to update the United States' <span class="hlt">Tsunami</span> Warning System software currently employed at the Pacific <span class="hlt">Tsunami</span> Warning Center (Eva Beach, Hawaii) and the National <span class="hlt">Tsunami</span> Warning Center (Palmer, Alaska). This entirely open source software project will integrate various seismic processing utilities with the National Weather Service Weather Forecast Office's core software, AWIPS2. For the real-time and near real-time seismic processing aspect of this project, NOAA has elected to integrate the open source portions of GFZ's SeisComP 3 (SC3) processing system into AWIPS2. To provide for better <span class="hlt">tsunami</span> threat assessments we are developing open source tools for magnitude estimations (e.g., moment magnitude, energy magnitude, surface wave magnitude), detection of slow earthquakes with the Theta discriminant, moment tensor inversions (e.g. W-phase and teleseismic body waves), finite fault inversions, and array processing. With our reliance on common data formats such as QuakeML and seismic community standard messaging systems, all new facilities introduced into AWIPS2 and SC3 will be available as stand-alone tools or could be easily integrated into other real time seismic monitoring systems such as Earthworm, Antelope, etc. Additionally, we have developed a template based design paradigm so that the developer or scientist can efficiently create upgrades, replacements, and/or new metrics to the seismic data processing with only a cursory knowledge of the underlying SC3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.S31C..08T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.S31C..08T"><span>Probabilistic <span class="hlt">Tsunami</span> Hazard Analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thio, H. K.; Ichinose, G. A.; Somerville, P. G.; Polet, J.</p> <p>2006-12-01</p> <p>The recent <span class="hlt">tsunami</span> disaster caused by the 2004 Sumatra-Andaman earthquake has focused our attention to the hazard posed by large earthquakes that occur under water, in particular subduction zone earthquakes, and the <span class="hlt">tsunamis</span> that they <span class="hlt">generate</span>. Even though these kinds of events are rare, the very large loss of life and material destruction caused by this earthquake warrant a significant effort towards the mitigation of the <span class="hlt">tsunami</span> hazard. For ground motion hazard, Probabilistic Seismic Hazard Analysis (PSHA) has become a standard practice in the evaluation and mitigation of seismic hazard to populations in particular with respect to structures, infrastructure and lifelines. Its ability to condense the complexities and variability of seismic activity into a manageable set of parameters greatly facilitates the design of effective seismic resistant buildings but also the planning of infrastructure projects. Probabilistic <span class="hlt">Tsunami</span> Hazard Analysis (PTHA) achieves the same goal for hazards posed by <span class="hlt">tsunami</span>. There are great advantages of implementing such a method to evaluate the total risk (seismic and <span class="hlt">tsunami</span>) to coastal communities. The method that we have developed is based on the traditional PSHA and therefore completely consistent with standard seismic practice. Because of the strong dependence of <span class="hlt">tsunami</span> wave heights on bathymetry, we use a full waveform <span class="hlt">tsunami</span> waveform computation in lieu of attenuation relations that are common in PSHA. By pre-computing and storing the <span class="hlt">tsunami</span> waveforms at points along the coast <span class="hlt">generated</span> for sets of subfaults that comprise larger earthquake faults, we can efficiently synthesize <span class="hlt">tsunami</span> waveforms for any slip distribution on those faults by summing the individual subfault <span class="hlt">tsunami</span> waveforms (weighted by their slip). This efficiency make it feasible to use Green's function summation in lieu of attenuation relations to provide very accurate estimates of <span class="hlt">tsunami</span> height for probabilistic calculations, where one typically computes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1813215F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1813215F"><span>Real-time determination of the worst <span class="hlt">tsunami</span> scenario based on Earthquake Early Warning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Furuya, Takashi; Koshimura, Shunichi; Hino, Ryota; Ohta, Yusaku; Inoue, Takuya</p> <p>2016-04-01</p> <p>In recent years, real-time <span class="hlt">tsunami</span> inundation forecasting has been developed with the advances of dense seismic monitoring, GPS Earth observation, offshore <span class="hlt">tsunami</span> observation networks, and high-performance computing infrastructure (Koshimura et al., 2014). Several uncertainties are involved in <span class="hlt">tsunami</span> inundation <span class="hlt">modeling</span> and it is believed that <span class="hlt">tsunami</span> <span class="hlt">generation</span> <span class="hlt">model</span> is one of the great uncertain sources. Uncertain <span class="hlt">tsunami</span> source <span class="hlt">model</span> has risk to underestimate <span class="hlt">tsunami</span> height, extent of inundation zone, and damage. <span class="hlt">Tsunami</span> source inversion using observed seismic, geodetic and <span class="hlt">tsunami</span> data is the most effective to avoid underestimation of <span class="hlt">tsunami</span>, but needs to expect more time to acquire the observed data and this limitation makes difficult to terminate real-time <span class="hlt">tsunami</span> inundation forecasting within sufficient time. Not waiting for the precise <span class="hlt">tsunami</span> observation information, but from disaster management point of view, we aim to determine the worst <span class="hlt">tsunami</span> source scenario, for the use of real-time <span class="hlt">tsunami</span> inundation forecasting and mapping, using the seismic information of Earthquake Early Warning (EEW) that can be obtained immediately after the event triggered. After an earthquake occurs, JMA's EEW estimates magnitude and hypocenter. With the constraints of earthquake magnitude, hypocenter and scaling law, we determine possible multi <span class="hlt">tsunami</span> source scenarios and start searching the worst one by the superposition of pre-computed <span class="hlt">tsunami</span> Green's functions, i.e. time series of <span class="hlt">tsunami</span> height at offshore points corresponding to 2-dimensional Gaussian unit source, e.g. Tsushima et al., 2014. Scenario analysis of our method consists of following 2 steps. (1) Searching the worst scenario range by calculating 90 scenarios with various strike and fault-position. From maximum <span class="hlt">tsunami</span> height of 90 scenarios, we determine a narrower strike range which causes high <span class="hlt">tsunami</span> height in the area of concern. (2) Calculating 900 scenarios that have different strike, dip, length</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70176416','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70176416"><span>Source characterization and <span class="hlt">tsunami</span> <span class="hlt">modeling</span> of submarine landslides along the Yucatán Shelf/Campeche Escarpment, southern Gulf of Mexico</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Chaytor, Jason D.; Geist, Eric L.; Paull, Charles K.; Caress, David W; Gwiazda, Roberto; Urrutia Fucugauchi, Jaime; Rebolledo Vieyra, Mario</p> <p>2016-01-01</p> <p>Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of <span class="hlt">tsunamis</span>. New multibeam bathymetry coverage reveals that mass wasting is pervasive along the Yucatán Shelf edge with several large composite landslides possibly removing as much as 70 km3 of the Cenozoic sedimentary section in a single event. Using GIS-based analysis, the dimensions of six landslides from the central and northern sections of the Yucatán Shelf/Campeche Escarpment were determined and used as input for preliminary <span class="hlt">tsunami</span> <span class="hlt">generation</span> and propagation <span class="hlt">models</span>. <span class="hlt">Tsunami</span> <span class="hlt">modeling</span> is performed to compare the propagation characteristics and distribution of maximum amplitudes throughout the GOM among the different landslide scenarios. Various factors such as landslide geometry, location along the Yucatán Shelf/Campeche Escarpment, and refraction during propagation result in significant variations in the affected part of the Mexican and US Gulf Coasts. In all cases, however, <span class="hlt">tsunami</span> amplitudes are greatest along the northern Yucatán Peninsula.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.1246Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.1246Y"><span>Assessment of Efficiency and Performance in <span class="hlt">Tsunami</span> Numerical <span class="hlt">Modeling</span> with GPU</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yalciner, Bora; Zaytsev, Andrey</p> <p>2017-04-01</p> <p>Non-linear shallow water equations (NSWE) are used to solve the propagation and coastal amplification of long waves and <span class="hlt">tsunamis</span>. Leap Frog scheme of finite difference technique is one of the satisfactory numerical methods which is widely used in these problems. <span class="hlt">Tsunami</span> numerical <span class="hlt">models</span> are necessary for not only academic but also operational purposes which need faster and accurate solutions. Recent developments in information technology provide considerably faster numerical solutions in this respect and are becoming one of the crucial requirements. <span class="hlt">Tsunami</span> numerical code NAMI DANCE uses finite difference numerical method to solve linear and non-linear forms of shallow water equations for long wave problems, specifically for <span class="hlt">tsunamis</span>. In this study, the new code is structured for Graphical Processing Unit (GPU) using CUDA API. The new code is applied to different (analytical, experimental and field) benchmark problems of <span class="hlt">tsunamis</span> for tests. One of those applications is 2011 Great East Japan <span class="hlt">tsunami</span> which was instrumentally recorded on various types of gauges including tide and wave gauges and offshore GPS buoys cabled Ocean Bottom Pressure (OBP) gauges and DART buoys. The accuracy of the results are compared with the measurements and fairly well agreements are obtained. The efficiency and performance of the code is also compared with the version using multi-core Central Processing Unit (CPU). Dependence of simulation speed with GPU on linear or non-linear solutions is also investigated. One of the results is that the simulation speed is increased up to 75 times comparing to the process time in the computer using single 4/8 thread multi-core CPU. The results are presented with comparisons and discussions. Furthermore how multi-dimensional finite difference problems fits towards GPU architecture is also discussed. The research leading to this study has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement No</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1914824L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1914824L"><span>Joint numerical study of the 2011 Tohoku-Oki <span class="hlt">tsunami</span>: comparative propagation simulations and high resolution coastal <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loevenbruck, Anne; Arpaia, Luca; Ata, Riadh; Gailler, Audrey; Hayashi, Yutaka; Hébert, Hélène; Heinrich, Philippe; Le Gal, Marine; Lemoine, Anne; Le Roy, Sylvestre; Marcer, Richard; Pedreros, Rodrigo; Pons, Kevin; Ricchiuto, Mario; Violeau, Damien</p> <p>2017-04-01</p> <p>This study is part of the joint actions carried out within TANDEM (<span class="hlt">Tsunamis</span> in northern AtlaNtic: Definition of Effects by <span class="hlt">Modeling</span>). This French project, mainly dedicated to the appraisal of coastal effects due to <span class="hlt">tsunami</span> waves on the French coastlines, was initiated after the catastrophic 2011 Tohoku-Oki <span class="hlt">tsunami</span>. This event, which tragically struck Japan, drew the attention to the importance of <span class="hlt">tsunami</span> risk assessment, in particular when nuclear facilities are involved. As a contribution to this challenging task, the TANDEM partners intend to provide guidance for the French Atlantic area based on numerical simulation. One of the identified objectives consists in designing, adapting and validating simulation codes for <span class="hlt">tsunami</span> hazard assessment. Besides an integral benchmarking workpackage, the outstanding database of the 2011 event offers the TANDEM partners the opportunity to test their numerical tools with a real case. As a prerequisite, among the numerous published seismic source <span class="hlt">models</span> arisen from the inversion of the various available records, a couple of coseismic slip distributions have been selected to provide common initial input parameters for the <span class="hlt">tsunami</span> computations. After possible adaptations or specific developments, the different codes are employed to simulate the Tohoku-Oki <span class="hlt">tsunami</span> from its source to the northeast Japanese coastline. The results are tested against the numerous <span class="hlt">tsunami</span> measurements and, when relevant, comparisons of the different codes are carried out. First, the results related to the oceanic propagation phase are compared with the offshore records. Then, the <span class="hlt">modeled</span> coastal impacts are tested against the onshore data. Flooding at a regional scale is considered, but high resolution simulations are also performed with some of the codes. They allow examining in detail the runup amplitudes and timing, as well as the complexity of the <span class="hlt">tsunami</span> interaction with the coastal structures. The work is supported by the Tandem project in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70179086','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70179086"><span>Introduction to “Global <span class="hlt">tsunami</span> science: Past and future, Volume I”</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.; Fritz, Hermann; Rabinovich, Alexander B.; Tanioka, Yuichiro</p> <p>2016-01-01</p> <p>Twenty-five papers on the study of <span class="hlt">tsunamis</span> are included in Volume I of the PAGEOPH topical issue “Global <span class="hlt">Tsunami</span> Science: Past and Future”. Six papers examine various aspects of <span class="hlt">tsunami</span> probability and uncertainty analysis related to hazard assessment. Three papers relate to deterministic hazard and risk assessment. Five more papers present new methods for <span class="hlt">tsunami</span> warning and detection. Six papers describe new methods for <span class="hlt">modeling</span> <span class="hlt">tsunami</span> hydrodynamics. Two papers investigate <span class="hlt">tsunamis</span> <span class="hlt">generated</span> by non-seismic sources: landslides and meteorological disturbances. The final three papers describe important case studies of recent and historical events. Collectively, this volume highlights contemporary trends in global <span class="hlt">tsunami</span> research, both fundamental and applied toward hazard assessment and mitigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70034155','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70034155"><span>International year of planet earth 7. Oceans, submarine land-slides and consequent <span class="hlt">tsunamis</span> in Canada</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Mosher, D.C.</p> <p>2009-01-01</p> <p>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 <span class="hlt">tsunamis</span>. Coastal landslides represent a specific threat because of their possible proximity to societal infrastructure and high <span class="hlt">tsunami</span> potential; they occur without warning and with little time lag between failure and <span class="hlt">tsunami</span> 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 <span class="hlt">generate</span> devastating <span class="hlt">tsunamis</span>. <span class="hlt">Tsunami</span> 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 <span class="hlt">tsunami</span> processes and sophisticated <span class="hlt">tsunami</span> propagation <span class="hlt">models</span>, are required to identify areas at high risk of impact.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.4672A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.4672A"><span><span class="hlt">Generation</span> of deterministic <span class="hlt">tsunami</span> hazard maps in the Bay of Cadiz, south-west Spain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Álvarez-Gómez, J. A.; Otero, L.; Olabarrieta, M.; González, M.; Carreño, E.; Baptista, M. A.; Miranda, J. M.; Medina, R.; Lima, V.</p> <p>2009-04-01</p> <p>The bay of Cádiz is a densely populated and industrialized area, and an important centre of tourism which multiplies its population in the summer months. This bay is situated in the Gulf of Cádiz, the south-west Atlantic margin of the Iberian Peninsula. From a tectonic point of view this area can be defined as a diffuse plate boundary, comprising the eastern edge of the Gloria and Tydeman transforms (where the deformation is mainly concentrated in these shear corridors), the Gorringe Bank, the Horseshoe Abyssal plain, the Portimao and Guadalquivir banks, and the western termination of the arcuated Gibraltar Arc. This deformation zone is the eastern edge of the Azores - Gibraltar seismic zone, being the present day boundary between the Eurasian and African plates. The motion between the plates is mainly convergent in the Gulf of Cádiz, but gradually changes to almost pure transcurrent along the Gloria Fault. The relative motion between the two plates is of the order of 4-5 mm/yr. In order to define the different tsunamigenic zones and to characterize its worst tsunamigenic source we have used seismic, structural and geological data. The numerical <span class="hlt">model</span> used to simulate the wave propagation and coastal inundation is the C3 (Cantabria, COMCOT and <span class="hlt">Tsunami</span>-Claw) <span class="hlt">model</span>. C3 is a hybrid finite difference-finite volume method which balances between efficiency and accuracy. For offshore domain in deep waters the <span class="hlt">model</span> applies an explicit finite difference scheme (FD), which is computationally fast and accurate in large grids. For near coast domains in coastal areas, it applies a finite volume scheme (VOF). It solves correctly the bore formation and the bore propagation. It is very effective solving the run-up and the run down. A set of five worst case tsunamigenic sources has been used with four different sea levels (minimum tide, most probable low tide, most probable high tide and maximum tide), in order to produce the following thematic maps with the C3 <span class="hlt">model</span>: maximum</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRB..123.2448W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRB..123.2448W"><span><span class="hlt">Tsunami</span> Scenarios Based on Interseismic <span class="hlt">Models</span> Along the Nankai Trough, Japan, From Seafloor and Onshore Geodesy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watanabe, Shun-ichi; Bock, Yehuda; Melgar, Diego; Tadokoro, Keiichi</p> <p>2018-03-01</p> <p>The recent availability of Global Positioning System-Acoustic seafloor geodetic observations enables us to resolve the spatial distribution of the slip deficit rate near the Nankai trough, southwestern Japan. Considering a tectonic block <span class="hlt">model</span> and the transient deformation due to the major earthquakes in this area, the slip deficit rate between the two relevant blocks can be estimated. In this study, we remove the time-dependent postseismic deformation of the 2004 southeastern off the Kii Peninsula earthquakes (MJMA 7.1, 7.4), which had led to the underestimation of the slip deficit rate in earlier studies. We <span class="hlt">model</span> the postearthquake viscoelastic relaxation using the 3D finite element <span class="hlt">model</span> with bi-viscous Burgers rheology, as well as the afterslip on the finite faults. The corrected Global Positioning System-Acoustic and land-based Global Navigation Satellite Systems data are aligned to the existing tectonic <span class="hlt">model</span> and used to estimate the slip deficit rate on the plate boundary. We then calculate the coseismic displacements and <span class="hlt">tsunami</span> wave propagation with the simple assumption that a hundred years of constant slip deficit accumulation was released instantaneously. To evaluate the influence of uncertainties in the plate interface geometry on a <span class="hlt">tsunami</span> <span class="hlt">model</span> for the Nankai trough, we investigated two different geometries and performed checkerboard inversion simulations. Although the two <span class="hlt">models</span> indicate roughly similar results, the peak height of the <span class="hlt">tsunami</span> wave and its arrival time at several points are significantly different in terms of the expected hazard.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NHESS..13.3249G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NHESS..13.3249G"><span><span class="hlt">Tsunami</span> evacuation <span class="hlt">modelling</span> as a tool for risk reduction: application to the coastal area of El Salvador</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>González-Riancho, P.; Aguirre-Ayerbe, I.; Aniel-Quiroga, I.; Abad, S.; González, M.; Larreynaga, J.; Gavidia, F.; Gutiérrez, O. Q.; Álvarez-Gómez, J. A.; Medina, R.</p> <p>2013-12-01</p> <p>Advances in the understanding and prediction of <span class="hlt">tsunami</span> impacts allow the development of risk reduction strategies for <span class="hlt">tsunami</span>-prone areas. This paper presents an integral framework for the formulation of <span class="hlt">tsunami</span> evacuation plans based on <span class="hlt">tsunami</span> vulnerability assessment and evacuation <span class="hlt">modelling</span>. This framework considers (i) the hazard aspects (<span class="hlt">tsunami</span> flooding characteristics and arrival time), (ii) the characteristics of the exposed area (people, shelters and road network), (iii) the current <span class="hlt">tsunami</span> warning procedures and timing, (iv) the time needed to evacuate the population, and (v) the identification of measures to improve the evacuation process. The proposed methodological framework aims to bridge between risk assessment and risk management in terms of <span class="hlt">tsunami</span> evacuation, as it allows for an estimation of the degree of evacuation success of specific management options, as well as for the classification and prioritization of the gathered information, in order to formulate an optimal evacuation plan. The framework has been applied to the El Salvador case study, demonstrating its applicability to site-specific response times and population characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH22A..04S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH22A..04S"><span>New Insights on <span class="hlt">Tsunami</span> Genesis and Energy Source</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Y. T.; Mohtat, A.; Yim, S. C.</p> <p>2017-12-01</p> <p>Conventional <span class="hlt">tsunami</span> theories suggest that earthquakes with significant vertical motions are more likely to <span class="hlt">generate</span> <span class="hlt">tsunamis</span>. In <span class="hlt">tsunami</span> <span class="hlt">models</span>, the vertical seafloor elevation is directly transferred to the sea-surface as the only initial condition. However, evidence from the 2011 Tohoku earthquake indicates otherwise; the vertical seafloor uplift was only 3 5 meters, too small to account for the resultant <span class="hlt">tsunami</span>. Surprisingly, the horizontal displacement was undeniably larger than anyone's expectation; about 60 meters at the frontal wedge of the fault plate, the largest slip ever recorded by in-situ instruments. The question is whether the horizontal motion of seafloor slopes had enhanced the <span class="hlt">tsunami</span> to become as destructive as observed. In this study, we provide proof: (1) Combining various measurements from the 2011 Tohoku event, we show that the earthquake transferred a total energy of 3.1e+15 joule to the ocean, in which the potential energy (PE) due to the vertical seafloor elevation (including seafloor uplift/subsidence plus the contribution from the horizontal displacement) was less than a half, while the kinetic energy (KE) due to the horizontal displacement velocity of the continental slope contributed a majority portion; (2) Using two modern state-of-the-art wave flumes and a three-dimensional <span class="hlt">tsunami</span> <span class="hlt">model</span>, we have reproduced the source energy and <span class="hlt">tsunamis</span> consistent with observations, including the 2004 Sumatra event. Based on the unified source energy formulation, we offer a competing theory to explain why some earthquakes <span class="hlt">generate</span> destructive <span class="hlt">tsunamis</span>, while others do not.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23A0236S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23A0236S"><span>Characteristics of Recent <span class="hlt">Tsunamis</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sweeney, A. D.; Eble, M. C.; Mungov, G.</p> <p>2017-12-01</p> <p>How long do <span class="hlt">tsunamis</span> impact a coast? How often is the largest <span class="hlt">tsunami</span> wave the first to arrive? How do measurements in the far field differ from those made close to the source? Extending the study of Eblé et al. (2015) who showed the prevalence of a leading negative phase, we assimilate and summarize characteristics of known <span class="hlt">tsunami</span> events recorded on bottom pressure and coastal water level stations throughout the world oceans to answer these and other questions. An extensive repository of data from the National Centers for Environmental Information (NCEI) archive for <span class="hlt">tsunami</span>-ready U.S. tide gauge stations, housing more than 200 sites going back 10 years are utilized as are some of the more 3000 marigrams (analog or paper tide gauge records) for <span class="hlt">tsunami</span> events. The focus of our study is on five <span class="hlt">tsunamis</span> <span class="hlt">generated</span> by earthquakes: 2010 Chile (Maule), 2011 East Japan (Tohoku), 2012 Haida Gwaii, 2014 Chile (Iquique), and 2015 Central Chile and one meteorologically <span class="hlt">generated</span> <span class="hlt">tsunami</span> on June 2013 along the U.S. East Coast and Caribbean. Reference: Eblé, M., Mungov, G. & Rabinovich, A. On the Leading Negative Phase of Major 2010-2014 <span class="hlt">Tsunamis</span>. Pure Appl. Geophys. (2015) 172: 3493. https://doi.org/10.1007/s00024-015-1127-5</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NHESD...2.4163F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NHESD...2.4163F"><span>Variable population exposure and distributed travel speeds in least-cost <span class="hlt">tsunami</span> evacuation <span class="hlt">modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fraser, S. A.; Wood, N. J.; Johnston, D. M.; Leonard, G. S.; Greening, P. D.; Rossetto, T.</p> <p>2014-06-01</p> <p>Evacuation of the population from a <span class="hlt">tsunami</span> hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance <span class="hlt">modelling</span> provides one approach to assessing <span class="hlt">tsunami</span> evacuation potential. Previous <span class="hlt">models</span> have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate evacuation departure time or assumed a common departure time for all exposed population. In this paper, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The <span class="hlt">model</span> is demonstrated for a case study of local-source <span class="hlt">tsunami</span> evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb-level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds can approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost <span class="hlt">modelling</span> of evacuation dynamics for evacuation planning, casualty <span class="hlt">modelling</span>, and development of emergency response training scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PApGe.172..757B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PApGe.172..757B"><span>South American <span class="hlt">Tsunamis</span> in Lyttelton Harbor, New Zealand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borrero, Jose C.; Goring, Derek G.</p> <p>2015-03-01</p> <p>At 2347 UTC on April 1, 2014 (12:47 pm April 2, 2014 NZDT) an earthquake with a moment magnitude of 8.2 occurred offshore of Iquique in northern Chile. The temblor <span class="hlt">generated</span> a <span class="hlt">tsunami</span> that was observed locally and recorded on tide gauges and deep ocean tsunameters close to the source region. While real time <span class="hlt">modeling</span> based on inverted tsunameter data and finite fault solutions of the earthquake rupture suggested that a damaging far-field <span class="hlt">tsunami</span> was not expected (and later confirmed), this event nevertheless reminded us of the threat posed to New Zealand by <span class="hlt">tsunami</span> <span class="hlt">generated</span> along the west coast of South America and from the Peru/Chile border region in particular. In this paper we quantitatively assess the <span class="hlt">tsunami</span> hazard at Lyttelton Harbor from South American <span class="hlt">tsunamis</span> through a review of historical accounts, numerical <span class="hlt">modeling</span> of past events and analysis of water level records. A sensitivity study for <span class="hlt">tsunamis</span> <span class="hlt">generated</span> along the length of the South American Subduction Zone is used to illustrate which section of the subduction zone would <span class="hlt">generate</span> the strongest response at Lyttelton while deterministic scenario <span class="hlt">modeling</span> of significant historical South American <span class="hlt">tsunamis</span> (i.e. 1868, 1877 and 1960) provide a quantitative estimate of the expected effects from possible future great earthquakes along the coast of South America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70024680','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70024680"><span>Complex earthquake rupture and local <span class="hlt">tsunamis</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, E.L.</p> <p>2002-01-01</p> <p>In contrast to far-field <span class="hlt">tsunami</span> amplitudes that are fairly well predicted by the seismic moment of subduction zone earthquakes, there exists significant variation in the scaling of local <span class="hlt">tsunami</span> amplitude with respect to seismic moment. From a global catalog of <span class="hlt">tsunami</span> runup observations this variability is greatest for the most frequently occuring tsunamigenic subduction zone earthquakes in the magnitude range of 7 < Mw < 8.5. Variability in local <span class="hlt">tsunami</span> runup scaling can be ascribed to <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> wave field. A wide range of slip distribution patterns are <span class="hlt">generated</span> using a stochastic, self-affine source <span class="hlt">model</span> that is consistent with the falloff of far-field seismic displacement spectra at high frequencies. The synthetic slip distributions <span class="hlt">generated</span> by the stochastic source <span class="hlt">model</span> 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 <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> amplitude can vary by a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NHESS..14.2975F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NHESS..14.2975F"><span>Variable population exposure and distributed travel speeds in least-cost <span class="hlt">tsunami</span> evacuation <span class="hlt">modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fraser, S. A.; Wood, N. J.; Johnston, D. M.; Leonard, G. S.; Greening, P. D.; Rossetto, T.</p> <p>2014-11-01</p> <p>Evacuation of the population from a <span class="hlt">tsunami</span> hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance <span class="hlt">modelling</span> provides one approach to assessing <span class="hlt">tsunami</span> evacuation potential. Previous <span class="hlt">models</span> have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source <span class="hlt">tsunami</span> evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost <span class="hlt">modelling</span> of evacuation dynamics for evacuation planning, casualty <span class="hlt">modelling</span>, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70133616','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70133616"><span>Variable population exposure and distributed travel speeds in least-cost <span class="hlt">tsunami</span> evacuation <span class="hlt">modelling</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Fraser, Stuart A.; Wood, Nathan J.; Johnston, David A.; Leonard, Graham S.; Greening, Paul D.; Rossetto, Tiziana</p> <p>2014-01-01</p> <p>Evacuation of the population from a <span class="hlt">tsunami</span> hazard zone is vital to reduce life-loss due to inundation. Geospatial least-cost distance <span class="hlt">modelling</span> provides one approach to assessing <span class="hlt">tsunami</span> evacuation potential. Previous <span class="hlt">models</span> have generally used two static exposure scenarios and fixed travel speeds to represent population movement. Some analyses have assumed immediate departure or a common evacuation departure time for all exposed population. Here, a method is proposed to incorporate time-variable exposure, distributed travel speeds, and uncertain evacuation departure time into an existing anisotropic least-cost path distance framework. The method is demonstrated for hypothetical local-source <span class="hlt">tsunami</span> evacuation in Napier City, Hawke's Bay, New Zealand. There is significant diurnal variation in pedestrian evacuation potential at the suburb level, although the total number of people unable to evacuate is stable across all scenarios. Whilst some fixed travel speeds approximate a distributed speed approach, others may overestimate evacuation potential. The impact of evacuation departure time is a significant contributor to total evacuation time. This method improves least-cost <span class="hlt">modelling</span> of evacuation dynamics for evacuation planning, casualty <span class="hlt">modelling</span>, and development of emergency response training scenarios. However, it requires detailed exposure data, which may preclude its use in many situations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7277T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7277T"><span>Source Rupture <span class="hlt">Models</span> and <span class="hlt">Tsunami</span> Simulations of Destructive October 28, 2012 Queen Charlotte Islands, British Columbia (Mw: 7.8) and September 16, 2015 Illapel, Chile (Mw: 8.3) Earthquakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Taymaz, Tuncay; Yolsal-Çevikbilen, Seda; Ulutaş, Ergin</p> <p>2016-04-01</p> <p>The finite-fault source rupture <span class="hlt">models</span> and numerical simulations of <span class="hlt">tsunami</span> waves <span class="hlt">generated</span> by 28 October 2012 Queen Charlotte Islands (Mw: 7.8), and 16 September 2015 Illapel-Chile (Mw: 8.3) earthquakes are presented. These subduction zone earthquakes have reverse faulting mechanisms with small amount of strike-slip components which clearly reflect the characteristics of convergence zones. The finite-fault slip <span class="hlt">models</span> of the 2012 Queen Charlotte and 2015 Chile earthquakes are estimated from a back-projection method that uses teleseismic P- waveforms to integrate the direct P-phase with reflected phases from structural discontinuities near the source. Non-uniform rupture <span class="hlt">models</span> of the fault plane, which are obtained from the finite fault <span class="hlt">modeling</span>, are used in order to describe the vertical displacement on seabed. In general, the vertical displacement of water surface was considered to be the same as ocean bottom displacement, and it is assumed to be responsible for the initial water surface deformation gives rise to occurrence of <span class="hlt">tsunami</span> waves. In this study, it was calculated by using the elastic dislocation algorithm. The results of numerical <span class="hlt">tsunami</span> simulations are compared with tide gauges and Deep-ocean Assessment and Reporting of <span class="hlt">Tsunami</span> (DART) buoy records. De-tiding, de-trending, low-pass and high-pass filters were applied to detect <span class="hlt">tsunami</span> waves in deep ocean sensors and tide gauge records. As an example, the observed records and results of simulations showed that the 2012 Queen Charlotte Islands earthquake <span class="hlt">generated</span> about 1 meter <span class="hlt">tsunami</span>-waves in Maui and Hilo (Hawaii), 5 hours and 30 minutes after the earthquake. Furthermore, the calculated amplitudes and time series of the <span class="hlt">tsunami</span> waves of the recent 2015 Illapel (Chile) earthquake are exhibiting good agreement with the records of tide and DART gauges except at stations Valparaiso and Pichidangui (Chile). This project is supported by The Scientific and Technological Research Council of Turkey (TUBITAK</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1658e0004M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1658e0004M"><span>Risk mapping and <span class="hlt">tsunami</span> mitigation in Gunungkidul area, Yogyakarta</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mardiatno, Djati; Sunarto, WF, Lies Rahayu; Saptadi, Gatot; Ayuningtyas, Efrinda Ari</p> <p>2015-04-01</p> <p>Coastal area of Gunungkidul Regency is one of the areas prone to <span class="hlt">tsunami</span> in Indonesia. In contrary, currently, this area is very intensively developed as one of the favourite tourism destination. This paper is aimed at explaining <span class="hlt">tsunami</span> risk and a mitigation type in Gunungkidul Area, Yogyakarta. Digital elevation <span class="hlt">model</span> (DEM) and coastal morphology were used to <span class="hlt">generate</span> <span class="hlt">tsunami</span> hazard map. Vulnerability was analysed by utilizing land use data. Information from previous studies (e.g. from GTZ) were also considered for analysis. <span class="hlt">Tsunami</span> risk was classified into three classes, i.e. high risk, medium risk, and low risk and visualized in the form of <span class="hlt">tsunami</span> risk map. <span class="hlt">Tsunami</span> risk map is a tool which can be used as disaster reduction instrument, such as for evacuation routes planning. Based on the preliminary results of this research, it is clear that <span class="hlt">tsunami</span> risk in this area is varied depend on the morphological condition of the location. There are five coastal area selected as the location, i.e. Ngrenehan, Baron, Sepanjang, PulangSawal, and Sadeng. All locations have the high risk zone to <span class="hlt">tsunami</span>, especially for bay area. Evacuation routes were <span class="hlt">generated</span> for all locations by considering the local landscape condition. There are several differences of evacuation ways for each location.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..1113170C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..1113170C"><span>Improvement and speed optimization of numerical <span class="hlt">tsunami</span> <span class="hlt">modelling</span> program using OpenMP technology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chernov, A.; Zaytsev, A.; Yalciner, A.; Kurkin, A.</p> <p>2009-04-01</p> <p>Currently, the basic problem of <span class="hlt">tsunami</span> <span class="hlt">modeling</span> is low speed of calculations which is unacceptable for services of the operative notification. Existing algorithms of numerical <span class="hlt">modeling</span> of hydrodynamic processes of <span class="hlt">tsunami</span> waves are developed without taking the opportunities of modern computer facilities. There is an opportunity to have considerable acceleration of process of calculations by using parallel algorithms. We discuss here new approach to parallelization <span class="hlt">tsunami</span> <span class="hlt">modeling</span> code using OpenMP Technology (for multiprocessing systems with the general memory). Nowadays, multiprocessing systems are easily accessible for everyone. The cost of the use of such systems becomes much lower comparing to the costs of clusters. This opportunity also benefits all programmers to apply multithreading algorithms on desktop computers of researchers. Other important advantage of the given approach is the mechanism of the general memory - there is no necessity to send data on slow networks (for example Ethernet). All memory is the common for all computing processes; it causes almost linear scalability of the program and processes. In the new version of NAMI DANCE using OpenMP technology and multi-threading algorithm provide 80% gain in speed in comparison with the one-thread version for dual-processor unit. The speed increased and 320% gain was attained for four core processor unit of PCs. Thus, it was possible to reduce considerably time of performance of calculations on the scientific workstations (desktops) without complete change of the program and user interfaces. The further modernization of algorithms of preparation of initial data and processing of results using OpenMP looks reasonable. The final version of NAMI DANCE with the increased computational speed can be used not only for research purposes but also in real time <span class="hlt">Tsunami</span> Warning Systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1903f0003A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1903f0003A"><span>Road infrastructure resilience to <span class="hlt">tsunami</span> in Cilegon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arini, Srikandi Wahyu; Sumabrata, Jachrizal</p> <p>2017-11-01</p> <p>Indonesia is vulnerable to natural disasters. The highest number of natural disaster occurs on the west side of Java Island with the <span class="hlt">tsunami</span> as the most deadly. Cilegon, a densely populated city with high industrial activity is located on the west coast of Java Island with a gently sloping topography, hence it is vulnerable to <span class="hlt">tsunami</span>. Simulations conducted by the National Disaster Management Authority indicates that earthquakes with epicenters in the Sunda strait will cause <span class="hlt">tsunamis</span> which can sweep away the whole industrial area in one hour. The availability of evacuation routes which can accommodate the evacuation of large numbers of people within a short time is required. Road infrastructure resilience is essential to support the performance of the evacuation routes. Poor network resilience will reduce mobility and accessibility during the evacuation. The objectives of this paper are to analyze the impact of the earthquake-<span class="hlt">generated</span> <span class="hlt">tsunami</span> on the evacuation routes and to simulate and analyze the performance of existing evacuation routes in Cilegon. The limitations of the <span class="hlt">modeling</span> approaches including the current and future challenges in evacuation transport research and its applications are also discussed. The conclusion from this study is accurate data source are needed to build a more representative <span class="hlt">model</span> and predict the areas susceptible to <span class="hlt">tsunamis</span> vulnerable areas and to construct cogent <span class="hlt">tsunami</span> mitigation plans and actions for the most vulnerable areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NHESS..17.2245M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NHESS..17.2245M"><span><span class="hlt">Tsunami</span> evacuation plans for future megathrust earthquakes in Padang, Indonesia, considering stochastic earthquake scenarios</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muhammad, Ario; Goda, Katsuichiro; Alexander, Nicholas A.; Kongko, Widjo; Muhari, Abdul</p> <p>2017-12-01</p> <p>This study develops <span class="hlt">tsunami</span> evacuation plans in Padang, Indonesia, using a stochastic <span class="hlt">tsunami</span> simulation method. The stochastic results are based on multiple earthquake scenarios for different magnitudes (Mw 8.5, 8.75, and 9.0) that reflect asperity characteristics of the 1797 historical event in the same region. The <span class="hlt">generation</span> of the earthquake scenarios involves probabilistic <span class="hlt">models</span> of earthquake source parameters and stochastic synthesis of earthquake slip distributions. In total, 300 source <span class="hlt">models</span> are <span class="hlt">generated</span> to produce comprehensive <span class="hlt">tsunami</span> evacuation plans in Padang. The <span class="hlt">tsunami</span> hazard assessment results show that Padang may face significant <span class="hlt">tsunamis</span> causing the maximum <span class="hlt">tsunami</span> inundation height and depth of 15 and 10 m, respectively. A comprehensive <span class="hlt">tsunami</span> evacuation plan - including horizontal evacuation area maps, assessment of temporary shelters considering the impact due to ground shaking and <span class="hlt">tsunami</span>, and integrated horizontal-vertical evacuation time maps - has been developed based on the stochastic <span class="hlt">tsunami</span> simulation results. The developed evacuation plans highlight that comprehensive mitigation policies can be produced from the stochastic <span class="hlt">tsunami</span> simulation for future tsunamigenic events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH53D..04R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH53D..04R"><span><span class="hlt">Tsunami</span> normal modes with solid earth and atmospheric coupling and inversion of the TEC data to estimate <span class="hlt">tsunami</span> water height in the case of the Queen Charlotte <span class="hlt">tsunami</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakoto, V.; Lognonne, P. H.; Rolland, L.</p> <p>2016-12-01</p> <p>Large underwater earthquakes (Mw > 7) can transmit part of their energy to the surrounding ocean through large sea-floor motions, <span class="hlt">generating</span> <span class="hlt">tsunamis</span> that propagate over long distances. The forcing effect of long period ocean surface vibrations due to <span class="hlt">tsunami</span> waves on the atmosphere trigger atmospheric internal gravity waves (IGWs) that induce ionospheric disturbances when they reach the upper atmosphere. In this poster, we study the IGWs associated to <span class="hlt">tsunamis</span> using a normal modes 1D <span class="hlt">modeling</span> approach. Our <span class="hlt">model</span> is first applied to the case of the October 2012 Haida Gwaii <span class="hlt">tsunami</span> observed offshore Hawaii. We found three resonances between <span class="hlt">tsunami</span> modes and the atmospheric gravity modes occurring around 1.5 mHz, 2 mHz and 2.5 mHz, with a large fraction of the energy of the <span class="hlt">tsunami</span> modes transferred from the ocean to the atmosphere. At theses frequencies, the gravity branches are interacting with the <span class="hlt">tsunami</span> one and have large amplitude in the ocean. As opposed to the <span class="hlt">tsunami</span>, a fraction of their energy is therefore transferred from the atmosphere to the ocean. We also show that the fundamental of the gravity waves should arrive before the <span class="hlt">tsunami</span> due to higher group velocity below 1.6 mHz. We demonstrate that only the 1.5 mHz resonance of the <span class="hlt">tsunami</span> mode can trigger observable ionospheric perturbations, most often monitored using GPS dual-frequency measurements. Indeed, we show that the modes at 2 mHz and 2.5 mHz are already evanescent at the height of the F2 peak and have little energy in the ionosphere. This normal modes <span class="hlt">modeling</span> offers a novel and comprehensive study of the transfer function from a propagating <span class="hlt">tsunami</span> to the upper atmosphere. In particular, we can invert the perturbed TEC data induced by a <span class="hlt">tsunami</span> in order to estimate the amplitude of the <span class="hlt">tsunami</span> waveform using a least square method. This method has been performed in the case of the Haida Gwaii <span class="hlt">tsunami</span>. The results showed a good agreement with the measurement of the dart buoy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH11C..05H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH11C..05H"><span>The Puerto Rico Component of the National <span class="hlt">Tsunami</span> Hazard and Mitigation Program Pr-Nthmp</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huerfano Moreno, V. A.; Hincapie-Cardenas, C. M.</p> <p>2014-12-01</p> <p><span class="hlt">Tsunami</span> hazard assessment, detection, warning, education and outreach efforts are intended to reduce losses to life and property. The Puerto Rico Seismic Network (PRSN) is participating in an effort with local and federal agencies, to developing <span class="hlt">tsunami</span> hazard risk reduction strategies under the National <span class="hlt">Tsunami</span> Hazards and Mitigation Program (NTHMP). This grant supports the <span class="hlt">Tsunami</span>Ready program which is the base of the <span class="hlt">tsunami</span> preparedness and mitigation in PR. The Caribbean region has a documented history of damaging <span class="hlt">tsunamis</span> that have affected coastal areas. The seismic water waves originating in the prominent fault systems around PR are considered to be a near-field hazard for Puerto Rico and the Virgin islands (PR/VI) because they can reach coastal areas within a few minutes after the earthquake. Sources for local, regional and tele <span class="hlt">tsunamis</span> have been identified and <span class="hlt">modeled</span> and <span class="hlt">tsunami</span> evacuation maps were prepared for PR. These maps were <span class="hlt">generated</span> in three phases: First, hypothetical <span class="hlt">tsunami</span> scenarios on the basis of the parameters of potential underwater earthquakes were developed. Secondly, each of these scenarios was simulated. The third step was to determine the worst case scenario (MOM). The run-ups were drawn on GIS referenced maps and aerial photographs. These products are being used by emergency managers to educate the public and develop mitigation strategies. Online maps and related evacuation products are available to the public via the PR-TDST (PR <span class="hlt">Tsunami</span> Decision Support Tool). Currently all the 44 coastal municipalities were recognized as <span class="hlt">Tsunami</span>Ready by the US NWS. The main goal of the program is to declare Puerto Rico as <span class="hlt">Tsunami</span>Ready, including two cities that are not coastal but could be affected by <span class="hlt">tsunamis</span>. Based on these evacuation maps, <span class="hlt">tsunami</span> signs were installed, vulnerability profiles were created, communication systems to receive and disseminate <span class="hlt">tsunami</span> messages were installed in each TWFP, and <span class="hlt">tsunami</span> response plans were approved</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70189163','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70189163"><span>Influence of road network and population demand assumptions in evacuation <span class="hlt">modeling</span> for distant <span class="hlt">tsunamis</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Henry, Kevin; Wood, Nathan J.; Frazier, Tim G.</p> <p>2017-01-01</p> <p><span class="hlt">Tsunami</span> evacuation planning in coastal communities is typically focused on local events where at-risk individuals must move on foot in a matter of minutes to safety. Less attention has been placed on distant <span class="hlt">tsunamis</span>, where evacuations unfold over several hours, are often dominated by vehicle use and are managed by public safety officials. Traditional traffic simulation <span class="hlt">models</span> focus on estimating clearance times but often overlook the influence of varying population demand, alternative modes, background traffic, shadow evacuation, and traffic management alternatives. These factors are especially important for island communities with limited egress options to safety. We use the coastal community of Balboa Island, California (USA), as a case study to explore the range of potential clearance times prior to wave arrival for a distant <span class="hlt">tsunami</span> scenario. We use a first-in–first-out queuing simulation environment to estimate variations in clearance times, given varying assumptions of the evacuating population (demand) and the road network over which they evacuate (supply). Results suggest clearance times are less than wave arrival times for a distant <span class="hlt">tsunami</span>, except when we assume maximum vehicle usage for residents, employees, and tourists for a weekend scenario. A two-lane bridge to the mainland was the primary traffic bottleneck, thereby minimizing the effect of departure times, shadow evacuations, background traffic, boat-based evacuations, and traffic light timing on overall community clearance time. Reducing vehicular demand generally reduced clearance time, whereas improvements to road capacity had mixed results. Finally, failure to recognize non-residential employee and tourist populations in the vehicle demand substantially underestimated clearance time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011NHESS..11.2371R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NHESS..11.2371R"><span>High resolution <span class="hlt">tsunami</span> <span class="hlt">modelling</span> for the evaluation of potential risk areas in Setúbal (Portugal)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ribeiro, J.; Silva, A.; Leitão, P.</p> <p>2011-08-01</p> <p>The use of high resolution hydrodynamic <span class="hlt">modelling</span> to simulate the potential effects of <span class="hlt">tsunami</span> events can provide relevant information about the most probable inundation areas. Moreover, the consideration of complementary data such as the type of buildings, location of priority equipment, type of roads, enables mapping of the most vulnerable zones, computing of the expected damage on man-made structures, constrain of the definition of rescue areas and escape routes, adaptation of emergency plans and proper evaluation of the vulnerability associated with different areas and/or equipment. Such an approach was used to evaluate the specific risks associated with a potential occurrence of a <span class="hlt">tsunami</span> event in the region of Setúbal (Portugal), which was one of the areas most seriously affected by the 1755 <span class="hlt">tsunami</span>. In order to perform an evaluation of the hazard associated with the occurrence of a similar event, high resolution wave propagation simulations were performed considering different potential earthquake sources with different magnitudes. Based on these simulations, detailed inundation maps associated with the different events were produced. These results were combined with the available information on the vulnerability of the local infrastructures (building types, roads and streets characteristics, priority buildings) in order to impose restrictions in the production of high-scale potential damage maps, escape routes and emergency routes maps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.2547Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.2547Z"><span>Estimates of <span class="hlt">tsunami</span> damage for Russian coast of the Black Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zaytsev, Andrey; Yalciner, Ahmet; Pelinovsky, Efim</p> <p>2010-05-01</p> <p>The historic database of <span class="hlt">tsunamis</span> in the Black Sea contains 20 - 30 events with different level of validity, and at least six events occurred in 20th century. Numerical <span class="hlt">modeling</span> of the last historic events is performed in the framework of shallow-water theory with use of code NAMI-DANCE. The computed tide-gauge records in Russian coastal locations are in good agreement with instrumental data for the 1939 and 1966 <span class="hlt">tsunamis</span>. The <span class="hlt">tsunami</span> of the landslide origin occurred in Sochi in 1970 is <span class="hlt">modeled</span> in the framework of the two-layer <span class="hlt">model</span> realized in TUNAMI. Also, some hypothetic <span class="hlt">tsunamis</span> <span class="hlt">generated</span> in the open part of the Black Sea are computed and the distribution of the <span class="hlt">tsunami</span> height along the Russian and Turkish coast ais found. In particular, the <span class="hlt">tsunami</span> amplification near Sochi is highest to compare with other coastal locations on the Russian coast of Black Sea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.4271R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.4271R"><span>A Global Sensitivity Analysis Method on Maximum <span class="hlt">Tsunami</span> Wave Heights to Potential Seismic Source Parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ren, Luchuan</p> <p>2015-04-01</p> <p>A Global Sensitivity Analysis Method on Maximum <span class="hlt">Tsunami</span> Wave Heights to Potential Seismic Source Parameters Luchuan Ren, Jianwei Tian, Mingli Hong Institute of Disaster Prevention, Sanhe, Heibei Province, 065201, P.R. China It is obvious that the uncertainties of the maximum <span class="hlt">tsunami</span> wave heights in offshore area are partly from uncertainties of the potential seismic <span class="hlt">tsunami</span> source parameters. A global sensitivity analysis method on the maximum <span class="hlt">tsunami</span> wave heights to the potential seismic source parameters is put forward in this paper. The <span class="hlt">tsunami</span> wave heights are calculated by COMCOT ( the Cornell Multi-grid Coupled <span class="hlt">Tsunami</span> <span class="hlt">Model</span>), on the assumption that an earthquake with magnitude MW8.0 occurred at the northern fault segment along the Manila Trench and triggered a <span class="hlt">tsunami</span> in the South China Sea. We select the simulated results of maximum <span class="hlt">tsunami</span> wave heights at specific sites in offshore area to verify the validity of the method proposed in this paper. For ranking importance order of the uncertainties of potential seismic source parameters (the earthquake's magnitude, the focal depth, the strike angle, dip angle and slip angle etc..) in <span class="hlt">generating</span> uncertainties of the maximum <span class="hlt">tsunami</span> wave heights, we chose Morris method to analyze the sensitivity of the maximum <span class="hlt">tsunami</span> wave heights to the aforementioned parameters, and give several qualitative descriptions of nonlinear or linear effects of them on the maximum <span class="hlt">tsunami</span> wave heights. We quantitatively analyze the sensitivity of the maximum <span class="hlt">tsunami</span> wave heights to these parameters and the interaction effects among these parameters on the maximum <span class="hlt">tsunami</span> wave heights by means of the extended FAST method afterward. The results shows that the maximum <span class="hlt">tsunami</span> wave heights are very sensitive to the earthquake magnitude, followed successively by the epicenter location, the strike angle and dip angle, the interactions effect between the sensitive parameters are very obvious at specific site in offshore area, and there</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH41A1742K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH41A1742K"><span><span class="hlt">Tsunami</span> Focusing and Leading Amplitude</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanoglu, U.</p> <p>2016-12-01</p> <p><span class="hlt">Tsunamis</span> transform substantially through spatial and temporal spreading from their source region. This substantial spreading might result unique maximum <span class="hlt">tsunami</span> wave heights which might be attributed to the source configuration, directivity, the waveguide structures of mid-ocean ridges and continental shelves, focusing and defocusing through submarine seamounts, random focusing due to small changes in bathymetry, dispersion, and, most likely, combination of some of these effects. In terms of the maximum <span class="hlt">tsunami</span> wave height, after Okal and Synolakis (2016 Geophys. J. Int. 204, 719-735), it is clear that dispersion would be one of the reasons to drive the leading wave amplitude in a <span class="hlt">tsunami</span> wave train. Okal and Synolakis (2016), referring to this phenomenon as sequencing -later waves in the train becoming higher than the leading one, considered Hammack's (1972, Ph.D. Dissertation, Calif. Inst. Tech., 261 pp) formalism, in addition to LeMéhauté and Wang's (1995 Water waves <span class="hlt">generated</span> by underwater explosion, World Scientific, 367 pp), to evaluate linear dispersive <span class="hlt">tsunami</span> propagation from a circular plug uplifted on an ocean of constant depth. They identified transition distance, as the second wave being larger, performing parametric study for the radius of the plug and the depth of the ocean. Here, we extend Okal and Synolakis' (2016) analysis to an initial wave field with a finite crest length and, in addition, to a most common <span class="hlt">tsunami</span> initial wave form of N-wave (Tadepalli and Synolakis, 1994 Proc. R. Soc. A: Math. Phys. Eng. Sci. 445, 99-112). First, we investigate the focusing feature in the leading-depression side, which enhance <span class="hlt">tsunami</span> wave height as presented by Kanoglu et al. (2013 Proc. R. Soc. A: Math. Phys. Eng. Sci. 469, 20130015). We then discuss the results in terms of leading wave amplitude presenting a parametric study and identify a simple relation for the transition distance. The solution presented here could be used to better analyze dispersive</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH41A1758L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH41A1758L"><span>M9.1 Cascadia Subduction Zone Earthquake <span class="hlt">Tsunami</span> Inundation <span class="hlt">Modeling</span> of Sequim Bay and Lopez Island, Washington</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, C. J.; Cakir, R.; Walsh, T. J.; LeVeque, R. J.; Adams, L. M.; Gonzalez, F. I.</p> <p>2016-12-01</p> <p>The Strait of Juan de Fuca and adjacent coastal zone are prone to <span class="hlt">tsunami</span> hazard triggered by a M9+ Cascadia Subduction Zone (CSZ) earthquake. In addition to the numerous <span class="hlt">tsunami</span> deposits observed on the outer coast, there is geological evidence for nine sandy or muddy <span class="hlt">tsunami</span> layers deposited in last 2500-year period in a tidal marsh area of Discovery Bay, Northeastern Olympic Peninsula, Washington (Williams et al., 2005, The Holocene, v. 15, no. 1). Thus, it is important to assess the potential <span class="hlt">tsunami</span> hazard due to a future M9+ CSZ earthquake event that may impact local communities in and near Discovery Bay area . In this study, we conducted <span class="hlt">tsunami</span> simulations using Clawpack-GeoClaw and the earthquake source scenario M9.1 CSZ, designated as "L1" (Witter et al., 2011, Oregon DOGAMI Special Paper 43). A fine-resolution (1/3 arc-second) NOAA digital elevation <span class="hlt">model</span> (DEM) was used to provide a high resolution <span class="hlt">tsunami</span> inundation simulation in Sequim Bay (about 5 miles west of Discovery Bay), Clallam county and Lopez Island, San Juan County. The test gauges, set around major infrastructures and properties, provided estimates of wave height, wave velocity, and wave arrival time. The results will contribute to further improving mitigation planning and emergency response efforts of the counties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70137567','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70137567"><span>Sensitivity of <span class="hlt">tsunami</span> evacuation <span class="hlt">modeling</span> to direction and land cover assumptions</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Schmidtlein, Mathew C.; Wood, Nathan J.</p> <p>2015-01-01</p> <p>Although anisotropic least-cost-distance (LCD) <span class="hlt">modeling</span> is becoming a common tool for estimating pedestrian-evacuation travel times out of <span class="hlt">tsunami</span> hazard zones, there has been insufficient attention paid to understanding <span class="hlt">model</span> sensitivity behind the estimates. To support <span class="hlt">tsunami</span> risk-reduction planning, we explore two aspects of LCD <span class="hlt">modeling</span> as it applies to pedestrian evacuations and use the coastal community of Seward, Alaska, as our case study. First, we explore the sensitivity of <span class="hlt">modeling</span> to the direction of movement by comparing standard safety-to-hazard evacuation times to hazard-to-safety evacuation times for a sample of 3985 points in Seward's <span class="hlt">tsunami</span>-hazard zone. Safety-to-hazard evacuation times slightly overestimated hazard-to-safety evacuation times but the strong relationship to the hazard-to-safety evacuation times, slightly conservative bias, and shorter processing times of the safety-to-hazard approach make it the preferred approach. Second, we explore how variations in land cover speed conservation values (SCVs) influence <span class="hlt">model</span> performance using a Monte Carlo approach with one thousand sets of land cover SCVs. The LCD <span class="hlt">model</span> was relatively robust to changes in land cover SCVs with the magnitude of local <span class="hlt">model</span> sensitivity greatest in areas with higher evacuation times or with wetland or shore land cover types, where <span class="hlt">model</span> results may slightly underestimate travel times. This study demonstrates that emergency managers should be concerned not only with populations in locations with evacuation times greater than wave arrival times, but also with populations with evacuation times lower than but close to expected wave arrival times, particularly if they are required to cross wetlands or beaches.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011aogs...26..165P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011aogs...26..165P"><span>Regional Impact <span class="hlt">Modeling</span> of <span class="hlt">Tsunami</span> Propogation Into Mercury Bay, Whitianga, New Zealand — Implications for Hazard and Disaster Management at a Local Scale</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pickett, Vernon; Prasetya, Gegar</p> <p>2011-07-01</p> <p>Whitianga is a small coastal town located on the eastern coastline of the Coromandel Peninsula, New Zealand. Historical evidence has shown that the town and surrounding area is susceptible to <span class="hlt">tsunami</span> events, in particular to those <span class="hlt">tsunami</span> <span class="hlt">generated</span> in the far field, with up to three events occurring since European settlement in the middle to late 19th Century (1868, 1877, and 1960). The last event in May 1960 impacted much of the North Island's eastern coastline and resulted in waves of ˜1.8-C2.5m at Whitianga that inundated waterfront roads, several houses, and buildings, and resulted in many boats being swept from their moorings. However, more recent work identified that the area is also susceptible to locally <span class="hlt">generated</span> <span class="hlt">tsunami</span> from sources located along the Kermadec subduction system and associated volcanic arc that extends north eastward from New Zealand toward Tonga. The core of the study involves the application of a <span class="hlt">tsunami</span> hydrodynamic <span class="hlt">model</span> to provide detailed wave propagation and inundation information using a range of likely scenarios and to present this information so that that the community can understand the associated risks involved as a prelude to the development of a local emergency plan. This study shows that while source definition requires careful consideration, high resolution bathymetry and topographic data are also necessary to adequately assess the risk at a local level. The <span class="hlt">model</span> used in this study incorporates a combination of multibeam, and ground and non-ground striking LIDAR data, with the results of the <span class="hlt">modeling</span> providing useful information for stakeholders involved in the emergency planning process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1213241R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1213241R"><span>High Resolution <span class="hlt">Tsunami</span> <span class="hlt">Modelling</span> for the Evaluation of Potential Risk Areas in Setubal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ribeiro, João.; Silva, Adélio; Leitão, Paulo</p> <p>2010-05-01</p> <p><span class="hlt">Modeling</span> has a relevant role in today's natural hazards mitigation planning as it can cover a wide range of natural phenomena. This is also the case for an event like a <span class="hlt">tsunami</span>. In order to support the urban planning or prepare emergency response plans it is of major importance to be able to properly evaluate the vulnerability associated with different areas and/or equipments. The use of high resolution <span class="hlt">models</span> can provide relevant information about the most probable inundation areas which complemented with other data such as the type of buildings, location of prioritary equipments, etc., may effectively contribute to better identify the most vulnerable zones, define rescue and escape routes and adequate the emergency plans to the constraints associated to these type of events. In the framework of FP6 SCHEMA project these concepts are being applied to different test sites and a detailed evaluation of the vulnerability of buildings and people to a <span class="hlt">tsunami</span> event is being evaluated. One of the sites selected it is located in Portugal, in the Atlantic coast, and it refers to Setúbal area which is located about 40 km south of Lisbon. Within this site two specific locations are being evaluated: one is the city of Setúbal (in the Sado estuary right margin) and the other is the Tróia peninsula (in the Sado estuary left margin). Setúbal city is a medium size town with about 114,000 inhabitants while Tróia is a touristic resort located in a shallow area with a high seasonal occupation and has the river Sado as one of the main sources of income to the city. Setúbal was one of the Portuguese villages that was seriously damaged by the of 1755 earthquake event. The 1755 earthquake, also known as the Great Lisbon Earthquake, took place on 1 November 1755, the catholic holiday of All Saints, around 09:30 AM. The earthquake was followed by a <span class="hlt">tsunami</span> and fires which caused a huge destruction of Lisboa and Setúbal In the framework of the present study, a detailed evaluation of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH22A..01V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH22A..01V"><span>The Puerto Rico Component of the National <span class="hlt">Tsunami</span> Hazard and Mitigation Program (PR-NTHMP)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vanacore, E. A.; Huerfano Moreno, V. A.; Lopez, A. M.</p> <p>2015-12-01</p> <p>The Caribbean region has a documented history of damaging <span class="hlt">tsunamis</span> that have affected coastal areas. Of particular interest is the Puerto Rico - Virgin Islands (PRVI) region, where the proximity of the coast to prominent tectonic faults would result in near-field <span class="hlt">tsunamis</span>. <span class="hlt">Tsunami</span> hazard assessment, detection capabilities, warning, education and outreach efforts are common tools intended to reduce loss of life and property. It is for these reasons that the PRSN is participating in an effort with local and federal agencies to develop <span class="hlt">tsunami</span> hazard risk reduction strategies under the NTHMP. This grant supports the <span class="hlt">Tsunami</span>Ready program, which is the base of the <span class="hlt">tsunami</span> preparedness and mitigation in PR. In order to recognize threatened communities in PR as <span class="hlt">Tsunami</span>Ready by the US NWS, the PR Component of the NTHMP have identified and <span class="hlt">modeled</span> sources for local, regional and tele-<span class="hlt">tsunamis</span> and the results of simulations have been used to develop <span class="hlt">tsunami</span> response plans. The main goal of the PR-NTHMP is to strengthen resilient coastal communities that are prepared for <span class="hlt">tsunami</span> hazards, and recognize PR as <span class="hlt">Tsunami</span>Ready. Evacuation maps were <span class="hlt">generated</span> in three phases: First, hypothetical <span class="hlt">tsunami</span> scenarios of potential underwater earthquakes were developed, and these scenarios were then <span class="hlt">modeled</span> through during the second phase. The third phase consisted in determining the worst-case scenario based on the Maximum of Maximums (MOM). Inundation and evacuation zones were drawn on GIS referenced maps and aerial photographs. These products are being used by emergency managers to educate the public and develop mitigation strategies. Maps and related evacuation products, like evacuation times, can be accessed online via the PR <span class="hlt">Tsunami</span> Decision Support Tool. Based on these evacuation maps, <span class="hlt">tsunami</span> signs were installed, vulnerability profiles were created, communication systems to receive and disseminate <span class="hlt">tsunami</span> messages were installed in each TWFP, and <span class="hlt">tsunami</span> response plans were</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70042900','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70042900"><span>Anisotropic path <span class="hlt">modeling</span> to assess pedestrian-evacuation potential from Cascadia-related <span class="hlt">tsunamis</span> in the US Pacific Northwest</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wood, Nathan J.; Schmidtlein, Mathew C.</p> <p>2012-01-01</p> <p>Recent disasters highlight the threat that <span class="hlt">tsunamis</span> pose to coastal communities. When developing <span class="hlt">tsunami</span>-education efforts and vertical-evacuation strategies, emergency managers need to understand how much time it could take for a coastal population to reach higher ground before <span class="hlt">tsunami</span> waves arrive. To improve efforts to <span class="hlt">model</span> pedestrian evacuations from <span class="hlt">tsunamis</span>, we examine the sensitivity of least-cost-distance <span class="hlt">models</span> to variations in <span class="hlt">modeling</span> approaches, data resolutions, and travel-rate assumptions. We base our observations on the assumption that an anisotropic approach that uses path-distance algorithms and accounts for variations in land cover and directionality in slope is the most realistic of an actual evacuation landscape. We focus our efforts on the Long Beach Peninsula in Washington (USA), where a substantial residential and tourist population is threatened by near-field <span class="hlt">tsunamis</span> related to a potential Cascadia subduction zone earthquake. Results indicate thousands of people are located in areas where evacuations to higher ground will be difficult before arrival of the first <span class="hlt">tsunami</span> wave. Deviations from anisotropic <span class="hlt">modeling</span> assumptions substantially influence the amount of time likely needed to reach higher ground. Across the entire study, changes in resolution of elevation data has a greater impact on calculated travel times than changes in land-cover resolution. In particular areas, land-cover resolution had a substantial impact when travel-inhibiting waterways were not reflected in small-scale data. Changes in travel-speed parameters had a substantial impact also, suggesting the importance of public-health campaigns as a <span class="hlt">tsunami</span> risk-reduction strategy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70030665','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70030665"><span>Probabilistic analysis of <span class="hlt">tsunami</span> hazards</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, E.L.; Parsons, T.</p> <p>2006-01-01</p> <p>Determining the likelihood of a disaster is a key component of any comprehensive hazard assessment. This is particularly true for <span class="hlt">tsunamis</span>, even though most <span class="hlt">tsunami</span> hazard assessments have in the past relied on scenario or deterministic type <span class="hlt">models</span>. We discuss probabilistic <span class="hlt">tsunami</span> hazard analysis (PTHA) from the standpoint of integrating computational methods with empirical analysis of past <span class="hlt">tsunami</span> runup. PTHA is derived from probabilistic seismic hazard analysis (PSHA), with the main difference being that PTHA must account for far-field sources. The computational methods rely on numerical <span class="hlt">tsunami</span> propagation <span class="hlt">models</span> rather than empirical attenuation relationships as in PSHA in determining ground motions. Because a number of source parameters affect local <span class="hlt">tsunami</span> runup height, PTHA can become complex and computationally intensive. Empirical analysis can function in one of two ways, depending on the length and completeness of the <span class="hlt">tsunami</span> catalog. For site-specific studies where there is sufficient <span class="hlt">tsunami</span> runup data available, hazard curves can primarily be derived from empirical analysis, with computational methods used to highlight deficiencies in the <span class="hlt">tsunami</span> catalog. For region-wide analyses and sites where there are little to no <span class="hlt">tsunami</span> data, a computationally based method such as Monte Carlo simulation is the primary method to establish <span class="hlt">tsunami</span> hazards. Two case studies that describe how computational and empirical methods can be integrated are presented for Acapulco, Mexico (site-specific) and the U.S. Pacific Northwest coastline (region-wide analysis).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.8288B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.8288B"><span>CoopEUS Case Study: <span class="hlt">Tsunami</span> <span class="hlt">Modelling</span> and Early Warning Systems for Near Source Areas (Mediterranean, Juan de Fuca).</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beranzoli, Laura; Best, Mairi; Chierici, Francesco; Embriaco, Davide; Galbraith, Nan; Heeseman, Martin; Kelley, Deborah; Pirenne, Benoit; Scofield, Oscar; Weller, Robert</p> <p>2015-04-01</p> <p>There is a need for <span class="hlt">tsunami</span> <span class="hlt">modeling</span> and early warning systems for near-source areas. For example this is a common public safety threat in the Mediterranean and Juan de Fuca/NE Pacific Coast of N.A.; Regions covered by the EMSO, OOI, and ONC ocean observatories. Through the CoopEUS international cooperation project, a number of environmental research infrastructures have come together to coordinate efforts on environmental challenges; this <span class="hlt">tsunami</span> case study tackles one such challenge. There is a mutual need of <span class="hlt">tsunami</span> event field data and <span class="hlt">modeling</span> to deepen our experience in testing methodology and developing real-time data processing. <span class="hlt">Tsunami</span> field data are already available for past events, part of this use case compares these for compatibility, gap analysis, and <span class="hlt">model</span> groundtruthing. It also reviews sensors needed and harmonizes instrument settings. Sensor metadata and registries are compared, harmonized, and aligned. Data policies and access are also compared and assessed for gap analysis. <span class="hlt">Modelling</span> algorithms are compared and tested against archived and real-time data. This case study will then be extended to other related <span class="hlt">tsunami</span> data and <span class="hlt">model</span> sources globally with similar geographic and seismic scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.S53A1036M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.S53A1036M"><span>New Theory for <span class="hlt">Tsunami</span> Propagation and Estimation of <span class="hlt">Tsunami</span> Source Parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mindlin, I. M.</p> <p>2007-12-01</p> <p> the area R, and the average magnitude of the sea surface displacement at the margin of the wave originating area h are estimated using tide gauges records. The results are compared (and, in the author's opinion, are in line) with the estimates known in the literature. Compared to the methods employed in the literature, there is no need to use bathymetry (and, consequently, refraction diagrams) for the estimations. The present paper follows closely earlier works [Mindlin I.M., 1996; Mindlin I.M. J. Appl. Math. Phys. (ZAMP), 2004, vol.55, pp. 781-799] and adds to their theoretical results. Example. The Hiuganada earthquake of 1968, April, 1, 9h 42m JST. A <span class="hlt">tsunami</span> of moderate size arrived at the coast of the south-western part of Shikoku and the eastern part of Kyushu, Japan. <span class="hlt">Tsunami</span> parameters listed above are estimated with the theory being discussed for two <span class="hlt">models</span> of <span class="hlt">tsunami</span> <span class="hlt">generation</span>: (a) by initial free surface displacement (the case for numerical studies): E=1.91· 1012J, R=22km, h=17.2cm; and (b) by a sudden change in the velocity field of initially still water: E=8.78· 1012J, R=20.4km, h=9.2cm. These values are in line with known estimates [Soloviev S.L., Go Ch.N. Catalogue of <span class="hlt">tsunami</span> in the West of Pacific Ocean. Moscow, 1974]: E=1.3· 1013J (attributed to Hatori), E=(1.4 - 2.2)· 1012J (attributed to Aida), R=21.2km, h=20cm [Hatory T., Bull. Earthq. Res. Inst., Tokyo Univ., 1969, vol. 47, pp. 55-63]. Also, estimates are obtained for the values that could not be found based on shallow water wave theory: (a) H=3.43m and (b) H=1.38m, T=16.4sec.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.1590M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.1590M"><span>Coastal Digital Elevation <span class="hlt">Models</span> (DEMs) for <span class="hlt">tsunami</span> hazard assessment on the French coasts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maspataud, Aurélie; Biscara, Laurie; Hébert, Hélène; Schmitt, Thierry; Créach, Ronan</p> <p>2015-04-01</p> <p>Building precise and up-to-date coastal DEMs is a prerequisite for accurate <span class="hlt">modeling</span> and forecasting of hydrodynamic processes at local scale. Marine flooding, originating from <span class="hlt">tsunamis</span>, storm surges or waves, is one of them. Some high resolution DEMs are being <span class="hlt">generated</span> for multiple coast configurations (gulf, embayment, strait, estuary, harbor approaches, low-lying areas…) along French Atlantic and Channel coasts. This work is undertaken within the framework of the TANDEM project (<span class="hlt">Tsunamis</span> in the Atlantic and the English ChaNnel: Definition of the Effects through numerical <span class="hlt">Modeling</span>) (2014-2017). DEMs boundaries were defined considering the vicinity of French civil nuclear facilities, site effects considerations and potential tsunamigenic sources. Those were identified from available historical observations. Seamless integrated topographic and bathymetric coastal DEMs will be used by institutions taking part in the study to simulate expected wave height at regional and local scale on the French coasts, for a set of defined scenarii. The main tasks were (1) the development of a new capacity of production of DEM, (2) aiming at the release of high resolution and precision digital field <span class="hlt">models</span> referred to vertical reference frameworks, that require (3) horizontal and vertical datum conversions (all source elevation data need to be transformed to a common datum), on the basis of (4) the building of (national and/or local) conversion grids of datum relationships based on known measurements. Challenges in coastal DEMs development deal with good practices throughout <span class="hlt">model</span> development that can help minimizing uncertainties. This is particularly true as scattered elevation data with variable density, from multiple sources (national hydrographic services, state and local government agencies, research organizations and private engineering companies) and from many different types (paper fieldsheets to be digitized, single beam echo sounder, multibeam sonar, airborne laser</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJAEO..46...63H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJAEO..46...63H"><span>Earth observation data based rapid flood-extent <span class="hlt">modelling</span> for <span class="hlt">tsunami</span>-devastated coastal areas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hese, Sören; Heyer, Thomas</p> <p>2016-04-01</p> <p>Earth observation (EO)-based mapping and analysis of natural hazards plays a critical role in various aspects of post-disaster aid management. Spatial very high-resolution Earth observation data provide important information for managing post-<span class="hlt">tsunami</span> activities on devastated land and monitoring re-cultivation and reconstruction. The automatic and fast use of high-resolution EO data for rapid mapping is, however, complicated by high spectral variability in densely populated urban areas and unpredictable textural and spectral land-surface changes. The present paper presents the results of the SENDAI project, which developed an automatic post-<span class="hlt">tsunami</span> flood-extent <span class="hlt">modelling</span> concept using RapidEye multispectral satellite data and ASTER Global Digital Elevation <span class="hlt">Model</span> Version 2 (GDEM V2) data of the eastern coast of Japan (captured after the Tohoku earthquake). In this paper, the authors developed both a bathtub-<span class="hlt">modelling</span> approach and a cost-distance approach, and integrated the roughness parameters of different land-use types to increase the accuracy of flood-extent <span class="hlt">modelling</span>. Overall, the accuracy of the developed <span class="hlt">models</span> reached 87-92%, depending on the analysed test site. The flood-<span class="hlt">modelling</span> approach was explained and results were compared with published approaches. We came to the conclusion that the cost-factor-based approach reaches accuracy comparable to published results from hydrological <span class="hlt">modelling</span>. However the proposed cost-factor approach is based on a much simpler dataset, which is available globally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70073331','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70073331"><span>Local <span class="hlt">tsunamis</span> and earthquake source parameters</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.; Dmowska, Renata; Saltzman, Barry</p> <p>1999-01-01</p> <p>This chapter establishes the relationship among earthquake source parameters and the <span class="hlt">generation</span>, propagation, and run-up of local <span class="hlt">tsunamis</span>. In general terms, displacement of the seafloor during the earthquake rupture is <span class="hlt">modeled</span> 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 <span class="hlt">tsunamis</span>. A parametric study is devised to examine the relative importance of individual earthquake source parameters on local <span class="hlt">tsunamis</span>, because the physics that describes <span class="hlt">tsunamis</span> from <span class="hlt">generation</span> 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 <span class="hlt">tsunami</span> 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 <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS1000a2113Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS1000a2113Y"><span>Analytical and Numerical <span class="hlt">Modeling</span> of <span class="hlt">Tsunami</span> Wave Propagation for double layer state in Bore</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuvaraj, V.; Rajasekaran, S.; Nagarajan, D.</p> <p>2018-04-01</p> <p><span class="hlt">Tsunami</span> wave enters into the river bore in the landslide. <span class="hlt">Tsunami</span> wave propagation are described in two-layer states. The velocity and amplitude of the <span class="hlt">tsunami</span> wave propagation are calculated using the double layer. The numerical and analytical solutions are given for the nonlinear equation of motion of the wave propagation in a bore.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70168678','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70168678"><span>The Pacific <span class="hlt">tsunami</span> warning system</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Pararas-Carayannis, G.</p> <p>1986-01-01</p> <p>The impact of <span class="hlt">tsunamis</span> on human societies can be traced back in written history to 480 BC, when the Minoan civilization in the Eastern Mediterranean was wiped out by great <span class="hlt">tsunami</span> waves <span class="hlt">generated</span> by the volcanic explosion of the island of Santorin. In the Pacific Ocean where the majority of these waves have been <span class="hlt">generated</span>, the historical record, although brief, shows tremendous destruction. In Japan which has one of the most populated coastal regions in the world and a long history of earthquake activity, <span class="hlt">tsunamis</span> have destroyed entire coastal communities. There is also history of <span class="hlt">tsunami</span> destruction in Alaska, in Hawaiian Islands, and in South America. </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70055623','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70055623"><span>Simulated <span class="hlt">tsunami</span> inundation for a range of Cascadia megathrust earthquake scenarios at Bandon, Oregon, USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Witter, Robert C.; Zhang, Yinglong J.; Wang, Kelin; Priest, George R.; Goldfinger, Chris; Stimely, Laura; English, John T.; Ferro, Paul A.</p> <p>2013-01-01</p> <p>Characterizations of <span class="hlt">tsunami</span> hazards along the Cascadia subduction zone hinge on uncertainties in megathrust rupture <span class="hlt">models</span> used for simulating <span class="hlt">tsunami</span> inundation. To explore these uncertainties, we constructed 15 megathrust earthquake scenarios using rupture <span class="hlt">models</span> that supply the initial conditions for <span class="hlt">tsunami</span> simulations at Bandon, Oregon. <span class="hlt">Tsunami</span> inundation varies with the amount and distribution of fault slip assigned to rupture <span class="hlt">models</span>, including <span class="hlt">models</span> where slip is partitioned to a splay fault in the accretionary wedge and <span class="hlt">models</span> that vary the updip limit of slip on a buried fault. Constraints on fault slip come from onshore and offshore paleoseismological evidence. We rank each rupture <span class="hlt">model</span> using a logic tree that evaluates a model’s consistency with geological and geophysical data. The scenarios provide inputs to a hydrodynamic <span class="hlt">model</span>, SELFE, used to simulate <span class="hlt">tsunami</span> <span class="hlt">generation</span>, propagation, and inundation on unstructured grids with <5–15 m resolution in coastal areas. <span class="hlt">Tsunami</span> simulations delineate the likelihood that Cascadia <span class="hlt">tsunamis</span> will exceed mapped inundation lines. Maximum wave elevations at the shoreline varied from ∼4 m to 25 m for earthquakes with 9–44 m slip and Mw 8.7–9.2. Simulated <span class="hlt">tsunami</span> inundation agrees with sparse deposits left by the A.D. 1700 and older <span class="hlt">tsunamis</span>. <span class="hlt">Tsunami</span> simulations for large (22–30 m slip) and medium (14–19 m slip) splay fault scenarios encompass 80%–95% of all inundation scenarios and provide reasonable guidelines for land-use planning and coastal development. The maximum <span class="hlt">tsunami</span> inundation simulated for the greatest splay fault scenario (36–44 m slip) can help to guide development of local <span class="hlt">tsunami</span> evacuation zones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH41B1722C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH41B1722C"><span>Transient <span class="hlt">Tsunamis</span> in Lakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Couston, L.; Mei, C.; Alam, M.</p> <p>2013-12-01</p> <p>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 <span class="hlt">generate</span> unexpectedly large <span class="hlt">tsunami</span> 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 <span class="hlt">tsunami</span> 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 <span class="hlt">model</span> equation in the Lagrangian framework to address the problem of transient landslide-<span class="hlt">tsunamis</span>. In this manner, the shorelines' three-dimensional motion is part of the solution. The <span class="hlt">model</span> 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 <span class="hlt">generated</span> wavefield. Specifically, for a slide moving down a plane beach, we show that edge-waves trapped by the shoreline and free</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70032527','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70032527"><span><span class="hlt">Tsunami</span> probability in the Caribbean Region</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Parsons, T.; Geist, E.L.</p> <p>2008-01-01</p> <p>We calculated <span class="hlt">tsunami</span> runup probability (in excess of 0.5 m) at coastal sites throughout the Caribbean region. We applied a Poissonian probability <span class="hlt">model</span> because of the variety of uncorrelated <span class="hlt">tsunami</span> sources in the region. Coastlines were discretized into 20 km by 20 km cells, and the mean <span class="hlt">tsunami</span> runup rate was determined for each cell. The remarkable ???500-year empirical record compiled by O'Loughlin and Lander (2003) was used to calculate an empirical <span class="hlt">tsunami</span> probability map, the first of three constructed for this study. However, it is unclear whether the 500-year record is complete, so we conducted a seismic moment-balance exercise using a finite-element <span class="hlt">model</span> of the Caribbean-North American plate boundaries and the earthquake catalog, and found that moment could be balanced if the seismic coupling coefficient is c = 0.32. <span class="hlt">Modeled</span> moment release was therefore used to <span class="hlt">generate</span> synthetic earthquake sequences to calculate 50 <span class="hlt">tsunami</span> runup scenarios for 500-year periods. We made a second probability map from numerically-calculated runup rates in each cell. Differences between the first two probability maps based on empirical and numerical-<span class="hlt">modeled</span> rates suggest that each captured different aspects of <span class="hlt">tsunami</span> <span class="hlt">generation</span>; the empirical <span class="hlt">model</span> may be deficient in primary plate-boundary events, whereas numerical <span class="hlt">model</span> rates lack backarc fault and landslide sources. We thus prepared a third probability map using Bayesian likelihood functions derived from the empirical and numerical rate <span class="hlt">models</span> and their attendant uncertainty to weight a range of rates at each 20 km by 20 km coastal cell. Our best-estimate map gives a range of 30-year runup probability from 0 - 30% regionally. ?? irkhaueser 2008.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.3906D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.3906D"><span>Hazard assessment for a submarine landslide <span class="hlt">generated</span> local-source <span class="hlt">tsunami</span> from Kaikoura Canyon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DuBois, J.</p> <p>2012-04-01</p> <p>The Kaikoura Canyon, sediment sink for the Canterbury rivers north of Christchurch, comes to within 500 meters of shore at Goose Bay and accumulates approximately 1.5x106 m3 of sediment each year (Lewis and Barnes, 1999). This sediment, which has accumulated to about seventy meters in thickness (Walters et al., 2006), exhibits tensional fractures, is located in a tectonically active area and could result in catastrophic failure and potentially a local-source <span class="hlt">tsunami</span> (Lewis and Banes, 1999; Lewis, 1998; Walters et al, 2006). Evidence suggests that this may have happened in the last two hundred years (Lewis, 1998; Lewis and Barnes 1999) and with a return period on the nearby Alpine and Hope faults also in the range of a one to two hundred years (Walters et al, 2006) could happen again relatively soon. A review of the historical record and oral traditions for Kaikoura shows that historically Kaikoura has been affected by 11 events of which 10 are from distant sources and one, though debatable, is possibly from a local source. There are some preserved traditions for the Kaikoura area. These taniwha stories from near Oaro and from the Lyell Creek have been repeated and changed though time though the general essence remains the same. These taniwha legends, though not conclusive, indicate a dangerous shoreline where people have been killed in the past, possibly by flooding or <span class="hlt">tsunami</span>. Archaeological investigations at Kaikoura found evidence of a Maori occupational layers interrupted by water-worn stones, a "lens of clean gravel between occupation layers" and in other areas of the excavation, the gravels separate discontinuous periods of occupation (Fomison 1963; Foster, 2006). Additionally "pea-gravel" sized greywacke pebbles were found dispersed throughout sections of the South Bay shore platforms, though they were attributesd to slopewash (Duckmanton, 1974) this is less likely since the nearby hills are limestone. A geological investigation along the Kaikoura Coast, at</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1410253F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1410253F"><span>Numerical Aspects of Nonhydrostatic Implementations Applied to a Parallel Finite Element <span class="hlt">Tsunami</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fuchs, A.; Androsov, A.; Harig, S.; Hiller, W.; Rakowsky, N.</p> <p>2012-04-01</p> <p>Based on the jeopardy of devastating <span class="hlt">tsunamis</span> and the unpredictability of such events, <span class="hlt">tsunami</span> <span class="hlt">modelling</span> as part of warning systems is still a contemporary topic. The <span class="hlt">tsunami</span> group of Alfred Wegener Institute developed the simulation tool TsunAWI as contribution to the Early Warning System in Indonesia. Although the precomputed scenarios for this purpose qualify for satisfying deliverables, the study of further improvements continues. While TsunAWI is governed by the Shallow Water Equations, an extension of the <span class="hlt">model</span> is based on a nonhydrostatic approach. At the arrival of a <span class="hlt">tsunami</span> wave in coastal regions with rough bathymetry, the term containing the nonhydrostatic part of pressure, that is neglected in the original hydrostatic <span class="hlt">model</span>, gains in importance. In consideration of this term, a better approximation of the wave is expected. Differences of hydrostatic and nonhydrostatic <span class="hlt">model</span> results are contrasted in the standard benchmark problem of a solitary wave runup on a plane beach. The observation data provided by Titov and Synolakis (1995) serves as reference. The nonhydrostatic approach implies a set of equations that are similar to the Shallow Water Equations, so the variation of the code can be implemented on top. However, this additional routines cause a lot of issues you have to cope with. So far the computations of the <span class="hlt">model</span> were purely explicit. In the nonhydrostatic version the determination of an additional unknown and the solution of a large sparse system of linear equations is necessary. The latter constitutes the lion's share of computing time and memory requirement. Since the corresponding matrix is only symmetric in structure and not in values, an iterative Krylov Subspace Method is used, in particular the restarted Generalized Minimal Residual Algorithm GMRES(m). With regard to optimization, we present a comparison of several combinations of sequential and parallel preconditioning techniques respective number of iterations and setup</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NHESS..17.1253B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NHESS..17.1253B"><span>Synthetic <span class="hlt">tsunami</span> waveform catalogs with kinematic constraints</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baptista, Maria Ana; Miranda, Jorge Miguel; Matias, Luis; Omira, Rachid</p> <p>2017-07-01</p> <p>In this study we present a comprehensive methodology to produce a synthetic <span class="hlt">tsunami</span> waveform catalogue in the northeast Atlantic, east of the Azores islands. The method uses a synthetic earthquake catalogue compatible with plate kinematic constraints of the area. We use it to assess the <span class="hlt">tsunami</span> hazard from the transcurrent boundary located between Iberia and the Azores, whose western part is known as the Gloria Fault. This study focuses only on earthquake-<span class="hlt">generated</span> <span class="hlt">tsunamis</span>. Moreover, we assume that the time and space distribution of the seismic events is known. To do this, we compute a synthetic earthquake catalogue including all fault parameters needed to characterize the seafloor deformation covering the time span of 20 000 years, which we consider long enough to ensure the representability of earthquake <span class="hlt">generation</span> on this segment of the plate boundary. The computed time and space rupture distributions are made compatible with global kinematic plate <span class="hlt">models</span>. We use the <span class="hlt">tsunami</span> empirical Green's functions to efficiently compute the synthetic <span class="hlt">tsunami</span> waveforms for the dataset of coastal locations, thus providing the basis for <span class="hlt">tsunami</span> impact characterization. We present the results in the form of offshore wave heights for all coastal points in the dataset. Our results focus on the northeast Atlantic basin, showing that earthquake-induced <span class="hlt">tsunamis</span> in the transcurrent segment of the Azores-Gibraltar plate boundary pose a minor threat to coastal areas north of Portugal and beyond the Strait of Gibraltar. However, in Morocco, the Azores, and the Madeira islands, we can expect wave heights between 0.6 and 0.8 m, leading to precautionary evacuation of coastal areas. The advantages of the method are its easy application to other regions and the low computation effort needed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.2499M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.2499M"><span>Performance of Landslide-HySEA <span class="hlt">tsunami</span> <span class="hlt">model</span> for NTHMP benchmarking validation process</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Macias, Jorge</p> <p>2017-04-01</p> <p>In its FY2009 Strategic Plan, the NTHMP required that all numerical <span class="hlt">tsunami</span> inundation <span class="hlt">models</span> be verified as accurate and consistent through a <span class="hlt">model</span> benchmarking process. This was completed in 2011, but only for seismic <span class="hlt">tsunami</span> sources and in a limited manner for idealized solid underwater landslides. Recent work by various NTHMP states, however, has shown that landslide <span class="hlt">tsunami</span> hazard may be dominant along significant parts of the US coastline, as compared to hazards from other tsunamigenic sources. To perform the above-mentioned validation process, a set of candidate benchmarks were proposed. These benchmarks are based on a subset of available laboratory date sets for solid slide experiments and deformable slide experiments, and include both submarine and subaerial slides. A benchmark based on a historic field event (Valdez, AK, 1964) close the list of proposed benchmarks. The Landslide-HySEA <span class="hlt">model</span> has participated in the workshop that was organized at Texas A&M University - Galveston, on January 9-11, 2017. The aim of this presentation is to show some of the numerical results obtained for Landslide-HySEA in the framework of this benchmarking validation/verification effort. Acknowledgements. This research has been partially supported by the Junta de Andalucía research project TESELA (P11-RNM7069), the Spanish Government Research project SIMURISK (MTM2015-70490-C02-01-R) and Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech. The GPU computations were performed at the Unit of Numerical Methods (University of Malaga).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123.4329R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123.4329R"><span><span class="hlt">Tsunami</span> Wave Height Estimation from GPS-Derived Ionospheric Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakoto, Virgile; Lognonné, Philippe; Rolland, Lucie; Coïsson, P.</p> <p>2018-05-01</p> <p>Large underwater earthquakes (Mw>7) can transmit part of their energy to the surrounding ocean through large seafloor motions, <span class="hlt">generating</span> <span class="hlt">tsunamis</span> that propagate over long distances. The forcing effect of <span class="hlt">tsunami</span> waves on the atmosphere <span class="hlt">generates</span> internal gravity waves that, when they reach the upper atmosphere, produce ionospheric perturbations. These perturbations are frequently observed in the total electron content (TEC) measured by multifrequency Global Navigation Satellite Systems (GNSS) such as GPS, GLONASS, and, in the future, Galileo. This paper describes the first inversion of the variation in sea level derived from GPS TEC data. We used a least squares inversion through a normal-mode summation <span class="hlt">modeling</span>. This technique was applied to three <span class="hlt">tsunamis</span> in far field associated to the 2012 Haida Gwaii, 2006 Kuril Islands, and 2011 Tohoku events and for Tohoku also in close field. With the exception of the Tohoku far-field case, for which the <span class="hlt">tsunami</span> reconstruction by the TEC inversion is less efficient due to the ionospheric noise background associated to geomagnetic storm, which occurred on the earthquake day, we show that the peak-to-peak amplitude of the sea level variation inverted by this method can be compared to the <span class="hlt">tsunami</span> wave height measured by a DART buoy with an error of less than 20%. This demonstrates that the inversion of TEC data with a <span class="hlt">tsunami</span> normal-mode summation approach is able to estimate quite accurately the amplitude and waveform of the first <span class="hlt">tsunami</span> arrival.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1611818R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611818R"><span>Operational <span class="hlt">tsunami</span> <span class="hlt">modeling</span> with TsunAWI - Examples for Indonesia and Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakowsky, Natalja; Androsov, Alexey; Harig, Sven; Immerz, Antonia; Fuchs, Annika; Behrens, Jörn; Danilov, Sergey; Hiller, Wolfgang; Schröter, Jens</p> <p>2014-05-01</p> <p>The numerical simulation code TsunAWI was developed in the framework of the German-Indonesian <span class="hlt">Tsunami</span> Early Warning System (GITEWS). The numerical simulation of prototypical <span class="hlt">tsunami</span> scenarios plays a decisive role in the a priory risk assessment for coastal regions and in the early warning process itself. TsunAWI is based on a finite element discretization, employs unstructured grids with high resolution along the coast, and includes inundation. This contribution gives an overview of the <span class="hlt">model</span> itself and presents two applications. For GITEWS, the existing scenario database covering 528 epicenters / 3450 scenarios from Sumatra to Bali was extended by 187 epicenters / 1100 scenarios in the Eastern Sunda Arc. Furthermore, about 1100 scenarios for the Western Sunda Arc were recomputed on the new <span class="hlt">model</span> domain covering the whole Indonesian Seas. These computations would not have been feasible in the beginning of the project. The unstructured computational grid contains 7 million nodes and resolves all coastal regions with 150m, some project regions and the surrounding of tide gauges with 50m, and the deep ocean with 12km edge length. While in the Western Sunda Arc, the large islands of Sumatra and Java shield the Northern Indonesian Archipelago, <span class="hlt">tsunamis</span> in the Eastern Sunda Arc can propagate to the North. The unstructured grid approach allows TsunAWI to easily simulate the complex propagation patterns with the self-interactions and the reflections at the coastal regions of myriads of islands. For the Hydrographic and Oceanographic Service of the Chilean Navy (SHOA), we calculated a small scenario database of 100 scenarios (sources by Universidad de Chile) to provide data for a lightweight decision support system prototype (built by DLR). This work is part of the initiation project "Multi hazard information and early warning system in cooperation with Chile" and aims at sharing our experience from GITEWS with the Chilean partners.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PApGe.173.3775O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PApGe.173.3775O"><span>Developing an Event-Tree Probabilistic <span class="hlt">Tsunami</span> Inundation <span class="hlt">Model</span> for NE Atlantic Coasts: Application to a Case Study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Omira, R.; Matias, L.; Baptista, M. A.</p> <p>2016-12-01</p> <p>This study constitutes a preliminary assessment of probabilistic <span class="hlt">tsunami</span> inundation in the NE Atlantic region. We developed an event-tree approach to calculate the likelihood of <span class="hlt">tsunami</span> flood occurrence and exceedance of a specific near-shore wave height for a given exposure time. Only <span class="hlt">tsunamis</span> of tectonic origin are considered here, taking into account local, regional, and far-field sources. The approach used here consists of an event-tree method that gathers probability <span class="hlt">models</span> for seismic sources, <span class="hlt">tsunami</span> numerical <span class="hlt">modeling</span>, and statistical methods. It also includes a treatment of aleatoric uncertainties related to source location and tidal stage. Epistemic uncertainties are not addressed in this study. The methodology is applied to the coastal test-site of Sines located in the NE Atlantic coast of Portugal. We derive probabilistic high-resolution maximum wave amplitudes and flood distributions for the study test-site considering 100- and 500-year exposure times. We find that the probability that maximum wave amplitude exceeds 1 m somewhere along the Sines coasts reaches about 60 % for an exposure time of 100 years and is up to 97 % for an exposure time of 500 years. The probability of inundation occurrence (flow depth >0 m) varies between 10 % and 57 %, and from 20 % up to 95 % for 100- and 500-year exposure times, respectively. No validation has been performed here with historical <span class="hlt">tsunamis</span>. This paper illustrates a methodology through a case study, which is not an operational assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1223169','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1223169"><span>Can Asteroid Airbursts Cause Dangerous <span class="hlt">Tsunami</span>?.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Boslough, Mark B.</p> <p></p> <p>I have performed a series of high-resolution hydrocode simulations to <span class="hlt">generate</span> “source functions” for <span class="hlt">tsunami</span> simulations as part of a proof-of-principle effort to determine whether or not the downward momentum from an asteroid airburst can couple energy into a dangerous <span class="hlt">tsunami</span> in deep water. My new CTH simulations show enhanced momentum multiplication relative to a nuclear explosion of the same yield. Extensive sensitivity and convergence analyses demonstrate that results are robust and repeatable for simulations with sufficiently high resolution using adaptive mesh refinement. I have provided surface overpressure and wind velocity fields to <span class="hlt">tsunami</span> <span class="hlt">modelers</span> to use as time-dependent boundarymore » conditions and to test the hypothesis that this mechanism can enhance the strength of the resulting shallow-water wave. The enhanced momentum result suggests that coupling from an over-water plume-forming airburst could be a more efficient <span class="hlt">tsunami</span> source mechanism than a collapsing impact cavity or direct air blast alone, but not necessarily due to the originally-proposed mechanism. This result has significant implications for asteroid impact risk assessment and airburst-<span class="hlt">generated</span> <span class="hlt">tsunami</span> will be the focus of a NASA-sponsored workshop at the Ames Research Center next summer, with follow-on funding expected.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH11B1556W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH11B1556W"><span>Estimated damage from the Cascadia Subduction Zone <span class="hlt">tsunami</span>: A <span class="hlt">model</span> comparisons using fragility curves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wiebe, D. M.; Cox, D. T.; Chen, Y.; Weber, B. A.; Chen, Y.</p> <p>2012-12-01</p> <p>Building damage from a hypothetical Cascadia Subduction Zone <span class="hlt">tsunami</span> was estimated using two methods and applied at the community scale. The first method applies proposed guidelines for a new ASCE 7 standard to calculate the flow depth, flow velocity, and momentum flux from a known runup limit and estimate of the total <span class="hlt">tsunami</span> energy at the shoreline. This procedure is based on a potential energy budget, uses the energy grade line, and accounts for frictional losses. The second method utilized numerical <span class="hlt">model</span> results from previous studies to determine maximum flow depth, velocity, and momentum flux throughout the inundation zone. The towns of Seaside and Canon Beach, Oregon, were selected for analysis due to the availability of existing data from previously published works. Fragility curves, based on the hydrodynamic features of the <span class="hlt">tsunami</span> flow (inundation depth, flow velocity, and momentum flux) and proposed design standards from ASCE 7 were used to estimate the probability of damage to structures located within the inundations zone. The analysis proceeded at the parcel level, using tax-lot data to identify construction type (wood, steel, and reinforced-concrete) and age, which was used as a performance measure when applying the fragility curves and design standards. The overall probability of damage to civil buildings was integrated for comparison between the two methods, and also analyzed spatially for damage patterns, which could be controlled by local bathymetric features. The two methods were compared to assess the sensitivity of the results to the uncertainty in the input hydrodynamic conditions and fragility curves, and the potential advantages of each method discussed. On-going work includes coupling the results of building damage and vulnerability to an economic input output <span class="hlt">model</span>. This <span class="hlt">model</span> assesses trade between business sectors located inside and outside the induction zone, and is used to measure the impact to the regional economy. Results highlight</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002cosp...34E2022H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002cosp...34E2022H"><span>The Big Splash: <span class="hlt">Tsunami</span> from Large Asteroid and Comet Impacts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hills, J.; Goda, M.</p> <p></p> <p>Asteroid and comet impacts produce a large range of damage. <span class="hlt">Tsunami</span> may produce most of the economic damage in large asteroid impacts. Large asteroid impacts produce worldwide darkness lasting several months that may kill more people by mass starvation, especially in developing countries, than would <span class="hlt">tsunami</span>, but the dust should not severely affect economic infrastructure. The <span class="hlt">tsunami</span> may even kill more people in developed countries with large coastal populations, such as the United States, than the starvation resulting from darkness. We have been determining which regions of Earth are most susceptible to asteroid <span class="hlt">tsunami</span> by simulating the effect of a large asteroid impact into mid-ocean. We have <span class="hlt">modeled</span> the effect of midAtlantic and midPacific impacts that produce craters 300 to 150 km in diameter. A KT-size impactor would cause the larger of these craters. We used a computer code that has successfully determined the runup and inundation from historical earthquake-<span class="hlt">generated</span> <span class="hlt">tsunami</span>. The code has been progressively improved to eliminate previous problems at the domain boundaries, so it now runs until the <span class="hlt">tsunami</span> inundation is complete. We find that the larger of these two midAtlantic impacts would engulf the entire Florida Peninsula. The smaller one would inundate the eastern third of the peninsula while a <span class="hlt">tsunami</span> passing through the Gulf of Cuba would inundate the West Coast of Florida. Impacts at three different sites in the Pacific show the great vulnerability of Tokyo and its surroundings to asteroid <span class="hlt">tsunami</span>. Mainland Asia is relatively protected from asteroid <span class="hlt">tsunami</span>. In Europe, the Iberian Peninsula and the Atlantic Providences of France are highly vulnerable to asteroid <span class="hlt">tsunami</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH43A1734B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH43A1734B"><span>Sources of information for <span class="hlt">tsunami</span> forecasting in New Zealand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barberopoulou, A.; Ristau, J. P.; D'Anastasio, E.; Wang, X.</p> <p>2013-12-01</p> <p><span class="hlt">Tsunami</span> science has evolved considerably in the last two decades due to technological advancements which also helped push for better numerical <span class="hlt">modelling</span> of the <span class="hlt">tsunami</span> phases (<span class="hlt">generation</span> to inundation). The deployment of DART buoys has also been a considerable milestone in <span class="hlt">tsunami</span> forecasting. <span class="hlt">Tsunami</span> forecasting is one of the parts that <span class="hlt">tsunami</span> <span class="hlt">modelling</span> feeds into and is related to response, preparedness and planning. Usually <span class="hlt">tsunami</span> forecasting refers to short-term forecasting that takes place in real-time after a <span class="hlt">tsunami</span> has or appears to have been <span class="hlt">generated</span>. In this report we refer to all types of forecasting (short-term or long-term) related to work in advance of a <span class="hlt">tsunami</span> impacting a coastline that would help in response, planning or preparedness. We look at the standard types of data (seismic, GPS, water level) that are available in New Zealand for <span class="hlt">tsunami</span> forecasting, how they are currently being used, other ways to use these data and provide recommendations for better utilisation. The main findings are: -Current investigations of the use of seismic parameters quickly obtained after an earthquake, have potential to provide critical information about the tsunamigenic potential of earthquakes. Further analysis of the most promising methods should be undertaken to determine a path to full implementation. -Network communication of the largest part of the GPS network is not currently at a stage that can provide sufficient data early enough for <span class="hlt">tsunami</span> warning. It is believed that it has potential, but changes including data transmission improvements may have to happen before real-time processing oriented to <span class="hlt">tsunami</span> early warning is implemented on the data that is currently provided. -Tide gauge data is currently under-utilised for <span class="hlt">tsunami</span> forecasting. Spectral analysis, modal analysis based on identified modes and arrival times extracted from the records can be useful in forecasting. -The current study is by no means exhaustive of the ways the different types</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911871N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911871N"><span>Probabilistic <span class="hlt">tsunami</span> hazard assessment in Greece for seismic sources along the segmented Hellenic Arc</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Novikova, Tatyana; Babeyko, Andrey; Papadopoulos, Gerassimos</p> <p>2017-04-01</p> <p>Greece and adjacent coastal areas are characterized by a high population exposure to <span class="hlt">tsunami</span> hazard. The Hellenic Arc is the most active geotectonic structure for the <span class="hlt">generation</span> of earthquakes and <span class="hlt">tsunamis</span>. We performed probabilistic <span class="hlt">tsunami</span> hazard assessment for selected locations of Greek coastlines which are the forecasting points officially used in the <span class="hlt">tsunami</span> warning operations by the Hellenic National <span class="hlt">Tsunami</span> Warning Center and the NEAMTWS/IOC/UNESCO. In our analysis we considered seismic sources for <span class="hlt">tsunami</span> <span class="hlt">generation</span> along the western, central and eastern segments of the Hellenic Arc. We first created a synthetic catalog as long as 10,000 years for all the significant earthquakes with magnitudes in the range from 6.0 to 8.5, the real events being included in this catalog. For each event included in the synthetic catalog a <span class="hlt">tsunami</span> was <span class="hlt">generated</span> and propagated using Boussinesq <span class="hlt">model</span>. The probability of occurrence for each event was determined by Gutenberg-Richter magnitude-frequency distribution. The results of our study are expressed as hazard curves and hazard maps. The hazard curves were obtained for the selected sites and present the annual probability of exceedance as a function of pick coastal <span class="hlt">tsunami</span> amplitude. Hazard maps represent the distribution of peak coastal <span class="hlt">tsunami</span> amplitudes corresponding to a fixed annual probability. In such forms our results can be easily compared to the ones obtained in other studies and further employed for the development of <span class="hlt">tsunami</span> risk management plans. This research is a contribution to the EU-FP7 <span class="hlt">tsunami</span> research project ASTARTE (Assessment, Strategy And Risk Reduction for <span class="hlt">Tsunamis</span> in Europe), grant agreement no: 603839, 2013-10-30.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23C1890I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23C1890I"><span>Preliminary <span class="hlt">tsunami</span> hazard assessment in British Columbia, Canada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Insua, T. L.; Grilli, A. R.; Grilli, S. T.; Shelby, M. R.; Wang, K.; Gao, D.; Cherniawsky, J. Y.; Harris, J. C.; Heesemann, M.; McLean, S.; Moran, K.</p> <p>2015-12-01</p> <p>Ocean Networks Canada (ONC), a not-for-profit initiative by the University of Victoria that operates several cabled ocean observatories, is developing a new <span class="hlt">generation</span> of ocean observing systems (referred to as Smart Ocean Systems™), involving advanced undersea observation technologies, data networks and analytics. The ONC <span class="hlt">Tsunami</span> project is a Smart Ocean Systems™ project that addresses the need for a near-field <span class="hlt">tsunami</span> detection system for the coastal areas of British Columbia. Recent studies indicate that there is a 40-80% probability over the next 50 for a significant <span class="hlt">tsunami</span> impacting the British Columbia (BC) coast with runups higher than 1.5 m. The NEPTUNE cabled ocean observatory, operated by ONC off of the west coast of British Columbia, could be used to detect near-field <span class="hlt">tsunami</span> events with existing instrumentation, including seismometers and bottom pressure recorders. As part of this project, new <span class="hlt">tsunami</span> simulations are underway for the BC coast. <span class="hlt">Tsunami</span> propagation is being simulated with the FUNWAVE-TVD <span class="hlt">model</span>, for a suite of new source <span class="hlt">models</span> representing Cascadia megathrust rupture scenarios. Simulations are performed by one-way coupling in a series of nested <span class="hlt">model</span> grids (from the source to the BC coast), whose bathymetry was developed based on digital elevation maps (DEMs) of the area, to estimate both <span class="hlt">tsunami</span> arrival time and coastal runup/inundation for different locations. Besides inundation, maps of additional parameters such as maximum current are being developed, that will aid in <span class="hlt">tsunami</span> hazard assessment and risk mitigation, as well as developing evacuation plans. We will present initial results of this work for the Port Alberni inlet, in particular Ucluelet, based on new source <span class="hlt">models</span> developed using the best available data. We will also present a <span class="hlt">model</span> validation using measurements of the 2011 transpacific Tohoku-oki <span class="hlt">tsunami</span> recorded in coastal BC by several instruments from various US and Canadian agencies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1919000G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1919000G"><span>Numerical simulation of the submarine landslides and <span class="hlt">tsunami</span> occurred at Port Valdez, AK during 1964 Alaska Earthquake with Landslide-HySEA <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>González-Vida, Jose M.; Ortega, Sergio; Macías, Jorge; Castro, Manuel J.; Escalante, Cipriano</p> <p>2017-04-01</p> <p>This is a benchmark problem recently proposed in the framework of the Landslide <span class="hlt">Tsunami</span> <span class="hlt">Model</span> Benchmarking Workshop organized by the NTHMP (National <span class="hlt">tsunami</span> Hazard mitigation program -USA-) at Galveston (USA). The benchmark is based on the historical event which occurred at Port Valdez, AK during the Alaska Earthquake of March 27, 1964. The great disaster during the Mw9.2 Alaska Earthquake happened in the dock and harbour area of Port Valdez, where a massive submarine landslide <span class="hlt">generated</span> a <span class="hlt">tsunami</span>, inundating the waterfront up to two blocks inland. Then, a second wave crossed the waterfront 10-15 minutes after the first wave, carrying a large amount of the debris. It has been described as a violent surging wave only slightly smaller than the first. It is believed that the second wave which flooded the waterfront was originated at the other side of the Port Valdez near the Shoup Bay moraine. The benchmark consists in simulating with the (GPU based) Landslide-HySEA <span class="hlt">model</span> the extent of inundation for two slide events, based on before and after bathymetry data, eye-witness observations of the event, and observed runup distribution. First, both landslides have been simulated separately, studying time series of the water waves at determined locations, runups at different areas and the extent of inundation around the first two blocks inland of Port Valdez. Then, the two landslides are triggered at the same time and the joint effect is studied. Obtained results are satisfactory and they agree with the existing observations. References Castro, M. J., Fernández-Nieto, E. D., González-Vida, J. M., Parés, C. (2011). Numerical Treatment of the Loss of Hyperbolicity of the Two-Layer Shallow-Water System. Journal of Scientific Computing, 48(1):16-40. Fernández, E.H., Bouchut, F., Bresh, D., Castro, M.J. and, Mangeney, A. (2008). A new Savage-Hutter type <span class="hlt">model</span> for submarine avalanches and <span class="hlt">generated</span> <span class="hlt">tsunami</span>. J. Comp. Phys., 227: 7720-7754. Fernández-Nieto, E.D., Castro, M</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NHESD...1.1173O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NHESD...1.1173O"><span><span class="hlt">Tsunami</span> hazard assessment in the southern Colombian Pacific Basin and a proposal to regenerate a previous barrier island as protection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otero, L. J.; Restrepo, J. C.; Gonzalez, M.</p> <p>2013-04-01</p> <p>In this study, the <span class="hlt">tsunami</span> hazard posed to 120 000 inhabitants of Tumaco (Colombia) is assessed, and an evaluation and analysis of regenerating the previous El Guano Island for <span class="hlt">tsunami</span> protection is conducted. El Guano Island was a sandy barrier island in front of the city of Tumaco until its disappearance during the <span class="hlt">tsunami</span> of 1979; the island is believed to have played a protective role, substantially reducing the scale of the disaster. The analysis is conducted by identifying seismotectonic parameters and focal mechanisms of <span class="hlt">tsunami</span> <span class="hlt">generation</span> in the area, determining seven potential <span class="hlt">generation</span> sources, applying a numerical <span class="hlt">model</span> for <span class="hlt">tsunami</span> <span class="hlt">generation</span> and propagation, and evaluating the effect of <span class="hlt">tsunamis</span> on Tumaco. The results show that in the current situation, this area is vulnerable to impact and flooding by <span class="hlt">tsunamis</span> originating nearby. El Guano Island was found to markedly reduce flood levels and the energy flux of <span class="hlt">tsunami</span> waves in Tumaco during the 1979 <span class="hlt">tsunami</span>. To reduce the risk of flooding due to <span class="hlt">tsunamis</span>, the regeneration and morphological modification of El Guano Island would help to protect Tumaco.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NHESS..14.1155O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NHESS..14.1155O"><span><span class="hlt">Tsunami</span> hazard assessment in the southern Colombian Pacific basin and a proposal to regenerate a previous barrier island as protection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otero, L. J.; Restrepo, J. C.; Gonzalez, M.</p> <p>2014-05-01</p> <p>In this study, the <span class="hlt">tsunami</span> hazard posed to 120 000 inhabitants of Tumaco (Colombia) is assessed, and an evaluation and analysis of regenerating the previous El Guano Island for <span class="hlt">tsunami</span> protection is conducted. El Guano Island was a sandy barrier island in front of the city of Tumaco until its disappearance during the <span class="hlt">tsunami</span> of 1979; the island is believed to have played a protective role, substantially reducing the scale of the disaster. The analysis is conducted by identifying seismotectonic parameters and focal mechanisms of <span class="hlt">tsunami</span> <span class="hlt">generation</span> in the area, determining seven potential <span class="hlt">generation</span> sources, applying a numerical <span class="hlt">model</span> for <span class="hlt">tsunami</span> <span class="hlt">generation</span> and propagation, and evaluating the effect of <span class="hlt">tsunamis</span> on Tumaco. The results show that in the current situation, this area is vulnerable to impact and flooding by <span class="hlt">tsunamis</span> originating nearby. El Guano Island was found to markedly reduce flood levels and the energy flux of <span class="hlt">tsunami</span> waves in Tumaco during the 1979 <span class="hlt">tsunami</span>. By reducing the risk of flooding due to <span class="hlt">tsunamis</span>, the regeneration and morphological modification of El Guano Island would help to protect Tumaco.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012GeoJI.191.1255H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012GeoJI.191.1255H"><span>The 2006 July 17 Java (Indonesia) <span class="hlt">tsunami</span> from satellite imagery and numerical <span class="hlt">modelling</span>: a single or complex source?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hébert, H.; Burg, P.-E.; Binet, R.; Lavigne, F.; Allgeyer, S.; Schindelé, F.</p> <p>2012-12-01</p> <p>The Mw 7.8 2006 July 17 earthquake off the southern coast of Java, Indonesia, has been responsible for a very large <span class="hlt">tsunami</span> causing more than 700 casualties. The <span class="hlt">tsunami</span> has been observed on at least 200 km of coastline in the region of Pangandaran (West Java), with run-up heights from 5 to more than 20 m. Such a large <span class="hlt">tsunami</span>, with respect to the source magnitude, has been attributed to the slow character of the seismic rupture, defining the event as a so-called <span class="hlt">tsunami</span> earthquake, but it has also been suggested that the largest run-up heights are actually the result of a second local landslide source. Here we test whether a single slow earthquake source can explain the <span class="hlt">tsunami</span> run-up, using a combination of new detailed data in the region of the largest run-ups and comparison with <span class="hlt">modelled</span> run-ups for a range of plausible earthquake source <span class="hlt">models</span>. Using high-resolution satellite imagery (SPOT 5 and Quickbird), the coastal impact of the <span class="hlt">tsunami</span> is refined in the surroundings of the high-security Permisan prison on Nusa Kambangan island, where 20 m run-up had been recorded directly after the event. These data confirm the extreme inundation lengths close to the prison, and extend the area of maximum impact further along the Nusa Kambangan island (about 20 km of shoreline), where inundation lengths reach several hundreds of metres, suggesting run-up as high as 10-15 m. <span class="hlt">Tsunami</span> <span class="hlt">modelling</span> has been conducted in detail for the high run-up Permisan area (Nusa Kambangan) and the PLTU power plant about 25 km eastwards, where run-up reached only 4-6 m and a video recording of the <span class="hlt">tsunami</span> arrival is available. For the Permisan prison a high-resolution DEM was built from stereoscopic satellite imagery. The regular basin of the PLTU plant was designed using photographs and direct observations. For the earthquake's mechanism, both static (infinite) and finite (kinematic) ruptures are investigated using two published source <span class="hlt">models</span>. The <span class="hlt">models</span> account rather well for the sea level</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH21A3830K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH21A3830K"><span>Influence of Earthquake Parameters on <span class="hlt">Tsunami</span> Wave Height and Inundation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kulangara Madham Subrahmanian, D.; Sri Ganesh, J.; Venkata Ramana Murthy, M.; V, R. M.</p> <p>2014-12-01</p> <p>After Indian Ocean <span class="hlt">Tsunami</span> (IOT) on 26th December, 2004, attempts are being made to assess the threat of <span class="hlt">tsunami</span> originating from different sources for different parts of India. The Andaman - Sumatra trench is segmented by transcurrent faults and differences in the rate of subduction which is low in the north and increases southward. Therefore key board <span class="hlt">model</span> with initial deformation calculated using different strike directions, slip rates, are used. This results in uncertainties in the earthquake parameters. This study is made to identify the location of origin of most destructive <span class="hlt">tsunami</span> for Southeast coast of India and to infer the influence of the earthquake parameters in <span class="hlt">tsunami</span> wave height travel time in deep ocean as well as in the shelf and inundation in the coast. Five tsunamigenic sources were considered in the Andaman - Sumatra trench taking into consideration the tectonic characters of the trench described by various authors and the <span class="hlt">modeling</span> was carried out using TUNAMI N2 code. The <span class="hlt">model</span> results were validated using the travel time and runup in the coastal areas and comparing the water elevation along Jason - 1's satellite track. The inundation results are compared from the field data. The assessment of the <span class="hlt">tsunami</span> threat for the area south of Chennai city the metropolitan city of South India shows that a <span class="hlt">tsunami</span> originating in Car Nicobar segment of the Andaman - Sumatra subduction zone can <span class="hlt">generate</span> the most destructive <span class="hlt">tsunami</span>. Sensitivity analysis in the <span class="hlt">modelling</span> indicates that fault length influences the results significantly and the <span class="hlt">tsunami</span> reaches early and with higher amplitude. Strike angle is also modifying the <span class="hlt">tsunami</span> followed by amount of slip.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NHESS..17.1871A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NHESS..17.1871A"><span>High-resolution <span class="hlt">modeling</span> of <span class="hlt">tsunami</span> run-up flooding: a case study of flooding in Kamaishi city, Japan, induced by the 2011 Tohoku <span class="hlt">tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akoh, Ryosuke; Ishikawa, Tadaharu; Kojima, Takashi; Tomaru, Mahito; Maeno, Shiro</p> <p>2017-11-01</p> <p>Run-up processes of the 2011 Tohoku <span class="hlt">tsunami</span> into the city of Kamaishi, Japan, were simulated numerically using 2-D shallow water equations with a new treatment of building footprints. The <span class="hlt">model</span> imposes an internal hydraulic condition of permeable and impermeable walls at the building footprint outline on unstructured triangular meshes. Digital data of the building footprint approximated by polygons were overlaid on a 1.0 m resolution terrain <span class="hlt">model</span>. The hydraulic boundary conditions were ascertained using conventional <span class="hlt">tsunami</span> propagation calculation from the seismic center to nearshore areas. Run-up flow calculations were conducted under the same hydraulic conditions for several cases having different building permeabilities. Comparison of computation results with field data suggests that the case with a small amount of wall permeability gives better agreement than the case with impermeable condition. Spatial mapping of an indicator for run-up flow intensity (IF = (hU2)max, where h and U respectively denote the inundation depth and flow velocity during the flood, shows fairly good correlation with the distribution of houses destroyed by flooding. As a possible mitigation measure, the influence of the buildings on the flow was assessed using a numerical experiment for solid buildings arrayed alternately in two lines along the coast. Results show that the buildings can prevent seawater from flowing straight to the city center while maintaining access to the sea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS32A..05W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS32A..05W"><span>Near-field <span class="hlt">tsunami</span> inferred from numerical <span class="hlt">modeling</span> of medieval overwash at Anegada, British Virgin Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wei, Y.; Ten Brink, U. S.; Atwater, B. F.; Tuttle, M. P.; Robert, H.; Feuillet, N.; Jennifer, W.; Fuentes, Z.</p> <p>2012-12-01</p> <p>In a comparison among numerical <span class="hlt">models</span> of storms and <span class="hlt">tsunamis</span>, only <span class="hlt">tsunami</span> waves of nearby origin manage to wash over an area where coral heads of medieval age are scattered hundreds of meters inland from the north shore of Anegada, British Virgin Islands. This low-lying island faces the Puerto Rico Trench 120 km to the north. The island's north shore, fringed by a coral reef 100-1200 m offshore, displays geological evidence for two levels of overwash. The medieval overwash, dated to AD 1200-1450, was the higher one. It is evidenced by scores of coral boulders scattered hundreds of meters inland. Some of them crossed the area of the modern storm berm at Soldier Wash, continued across a broad limestone rise 3-4 m above sea level, and came to rest on lower ground farther inland. Coral heads in four other areas, also medieval or older, came to rest hundreds of meters inland from beach ridges now 2-4 m above sea level. The later, lower-elevation overwash, dated to AD 1650-1800, laid down a sheet of sand and shell that extends as much as 1.5 km inland. The hypothetical causes for each event, tested by numerical <span class="hlt">modeling</span>, include (1) category IV and V hurricanes that differ in surge and wave heights; (2) the 1755 Lisbon earthquake or hypothetical medieval predecessor, at M 8.7 and M 9.0; (3) M 8.4 thrust earthquake along the Puerto Rico Trench between Hispaniola and Anegada; (4) M 8.7 thrust along the Puerto Rico Trench between Tortola and Antigua; (5) M 8.0 earthquake from normal faulting on the outer rise north of Anegada. The <span class="hlt">model</span> output includes extent of onshore flooding, depth and velocity of overland flow, and energy lost by <span class="hlt">tsunami</span> and hurricane waves as they cross the reef and continue across a shallow subtidal flat to Anegada's north shore. For the medieval overwash, the <span class="hlt">modeling</span> is most conclusive in testing various explanations for the coral boulders inland of Soldier Wash. The simulated hurricane waves do not wash inland of the storm berm; the height of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMSA21B..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMSA21B..01M"><span>Imaging, radio, and <span class="hlt">modeling</span> results pertaining to the ionospheric signature of the 11 March 2011 <span class="hlt">tsunami</span> over the Pacific Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Makela, J. J.; Lognonne, P.; Occhipinti, G.; Hebert, H.; Gehrels, T.; Coisson, P.; Rolland, L. M.; Allgeyer, S.; Kherani, A.</p> <p>2011-12-01</p> <p>The Mw=9.0 earthquake that occurred off the east coast of Honshu, Japan on 11 March 2011 launched a <span class="hlt">tsunami</span> that traveled across the Pacific Ocean, in turn launching vertically propagating atmospheric gravity waves. Upon reaching 250-350 km in altitude, these waves impressed their signature on the thermosphere/ionosphere system. We present observations of this signature obtained using a variety of radio instruments and an imaging system located on the islands of Hawaii. These measurements represent the first optical images recorded of the airglow signature resulting from the passage of a <span class="hlt">tsunami</span>. Results from these instruments clearly show wave structure propagating in the upper atmosphere with the same velocity as the ocean <span class="hlt">tsunami</span>, emphasizing the coupled nature of the ocean, atmosphere, and ionosphere. <span class="hlt">Modeling</span> results are also presented to highlight current understandings of this coupling process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70181804','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70181804"><span>Book review: Physics of <span class="hlt">tsunamis</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.</p> <p>2017-01-01</p> <p>“Physics of Tsunamis”, second edition, provides a comprehensive analytical treatment of the hydrodynamics associated with the <span class="hlt">tsunami</span> <span class="hlt">generation</span> process. The book consists of seven chapters covering 388 pages. Because the subject matter within each chapter is distinct, an abstract appears at the beginning and references appear at the end of each chapter, rather than at the end of the book. Various topics of <span class="hlt">tsunami</span> physics are examined largely from a theoretical perspective, although there is little information on how the physical descriptions are applied in numerical <span class="hlt">models</span>.“Physics of Tsunamis”, by B. W. Levin and M. A. Nosov, Second Edition, Springer, 2016; ISBN-10: 33-1933106X, ISBN-13: 978-331933-1065</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMOS43D1334S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMOS43D1334S"><span>The Contribution of Coseismic Displacements due to Splay Faults Into the Local Wavefield of the 1964 Alaska <span class="hlt">Tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Suleimani, E.; Ruppert, N.; Fisher, M.; West, D.; Hansen, R.</p> <p>2008-12-01</p> <p>The Alaska Earthquake Information Center conducts <span class="hlt">tsunami</span> inundation mapping for coastal communities in Alaska. For many locations in the Gulf of Alaska, the 1964 <span class="hlt">tsunami</span> <span class="hlt">generated</span> by the Mw9.2 Great Alaska earthquake may be the worst-case <span class="hlt">tsunami</span> scenario. We use the 1964 <span class="hlt">tsunami</span> observations to verify our numerical <span class="hlt">model</span> of <span class="hlt">tsunami</span> propagation and runup, therefore it is essential to use an adequate source function of the 1964 earthquake to reduce the level of uncertainty in the <span class="hlt">modeling</span> results. It was shown that the 1964 co-seismic slip occurred both on the megathrust and crustal splay faults (Plafker, 1969). Plafker (2006) suggested that crustal faults were a major contributor to vertical displacements that <span class="hlt">generated</span> local <span class="hlt">tsunami</span> waves. Using eyewitness arrival times of the highest observed waves, he suggested that the initial <span class="hlt">tsunami</span> wave was higher and closer to the shore, than if it was <span class="hlt">generated</span> by slip on the megathrust. We conduct a numerical study of two different source functions of the 1964 <span class="hlt">tsunami</span> to test whether the crustal splay faults had significant effects on local <span class="hlt">tsunami</span> runup heights and arrival times. The first source function was developed by Johnson et al. (1996) through joint inversion of the far-field <span class="hlt">tsunami</span> waveforms and geodetic data. The authors did not include crustal faults in the inversion, because the contribution of these faults to the far-field <span class="hlt">tsunami</span> was negligible. The second is the new coseismic displacement <span class="hlt">model</span> developed by Suito and Freymueller (2008, submitted). This <span class="hlt">model</span> extends the Montague Island fault farther along the Kenai Peninsula coast and thus reduces slip on the megathrust in that region. We also use an improved geometry of the Patton Bay fault based on the deep crustal seismic reflection and earthquake data. We propagate <span class="hlt">tsunami</span> waves <span class="hlt">generated</span> by both source <span class="hlt">models</span> across the Pacific Ocean and record wave amplitudes at the locations of the tide gages that recorded the 1964 <span class="hlt">tsunami</span>. As expected, the two</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70035545','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70035545"><span>Probabilistic <span class="hlt">tsunami</span> hazard assessment at Seaside, Oregon, for near-and far-field seismic sources</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gonzalez, F.I.; Geist, E.L.; Jaffe, B.; Kanoglu, U.; Mofjeld, H.; Synolakis, C.E.; Titov, V.V.; Areas, D.; Bellomo, D.; Carlton, D.; Horning, T.; Johnson, J.; Newman, J.; Parsons, T.; Peters, R.; Peterson, C.; Priest, G.; Venturato, A.; Weber, J.; Wong, F.; Yalciner, A.</p> <p>2009-01-01</p> <p>The first probabilistic <span class="hlt">tsunami</span> flooding maps have been developed. The methodology, called probabilistic <span class="hlt">tsunami</span> hazard assessment (PTHA), integrates <span class="hlt">tsunami</span> inundation <span class="hlt">modeling</span> with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum <span class="hlt">tsunami</span> amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year <span class="hlt">tsunami</span> is <span class="hlt">generated</span> most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year <span class="hlt">tsunami</span> is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, <span class="hlt">modeling</span> of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to <span class="hlt">tsunami</span> hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the <span class="hlt">tsunami</span> hazard, which can then be combined with vulnerability and exposure to yield estimates of <span class="hlt">tsunami</span> risk. Copyright 2009 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70031183','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70031183"><span>Distribution and sedimentary characteristics of <span class="hlt">tsunami</span> deposits along the Cascadia margin of western North America</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Peters, R.; Jaffe, B.; Gelfenbaum, G.</p> <p>2007-01-01</p> <p><span class="hlt">Tsunami</span> deposits have been found at more than 60 sites along the Cascadia margin of Western North America, and here we review and synthesize their distribution and sedimentary characteristics based on the published record. Cascadia <span class="hlt">tsunami</span> deposits are best preserved, and most easily identified, in low-energy coastal environments such as tidal marshes, back-barrier marshes and coastal lakes where they occur as anomalous layers of sand within peat and mud. They extend up to a kilometer inland in open coastal settings and several kilometers up river valleys. They are distinguished from other sediments by a combination of sedimentary character and stratigraphic context. Recurrence intervals range from 300-1000??years with an average of 500-600??years. The <span class="hlt">tsunami</span> deposits have been used to help evaluate and mitigate <span class="hlt">tsunami</span> hazards in Cascadia. They show that the Cascadia subduction zone is prone to great earthquakes that <span class="hlt">generate</span> large <span class="hlt">tsunamis</span>. The inclusion of <span class="hlt">tsunami</span> deposits on inundation maps, used in conjunction with results from inundation <span class="hlt">models</span>, allows a more accurate assessment of areas subject to <span class="hlt">tsunami</span> inundation. The application of sediment transport <span class="hlt">models</span> can help estimate <span class="hlt">tsunami</span> flow velocity and wave height, parameters which are necessary to help establish evacuation routes and plan development in <span class="hlt">tsunami</span> prone areas. ?? 2007.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.tmp...41F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.tmp...41F"><span>Implications on 1 + 1 D <span class="hlt">Tsunami</span> Runup <span class="hlt">Modeling</span> due to Time Features of the Earthquake Source</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fuentes, M.; Riquelme, S.; Ruiz, J.; Campos, J.</p> <p>2018-02-01</p> <p>The time characteristics of the seismic source are usually neglected in <span class="hlt">tsunami</span> <span class="hlt">modeling</span>, due to the difference in the time scale of both processes. Nonetheless, there are just a few analytical studies that intended to explain separately the role of the rise time and the rupture velocity. In this work, we extend an analytical 1 + 1 D solution for the shoreline motion time series, from the static case to the kinematic case, by including both rise time and rupture velocity. Our results show that the static case corresponds to a limit case of null rise time and infinite rupture velocity. Both parameters contribute in shifting the arrival time, but maximum runup may be affected by very slow ruptures and long rise time. Parametric analysis reveals that runup is strictly decreasing with the rise time while is highly amplified in a certain range of slow rupture velocities. For even lower rupture velocities, the <span class="hlt">tsunami</span> excitation vanishes and for larger, quicker approaches to the instantaneous case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1393F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1393F"><span>Implications on 1 + 1 D <span class="hlt">Tsunami</span> Runup <span class="hlt">Modeling</span> due to Time Features of the Earthquake Source</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fuentes, M.; Riquelme, S.; Ruiz, J.; Campos, J.</p> <p>2018-04-01</p> <p>The time characteristics of the seismic source are usually neglected in <span class="hlt">tsunami</span> <span class="hlt">modeling</span>, due to the difference in the time scale of both processes. Nonetheless, there are just a few analytical studies that intended to explain separately the role of the rise time and the rupture velocity. In this work, we extend an analytical 1 + 1 D solution for the shoreline motion time series, from the static case to the kinematic case, by including both rise time and rupture velocity. Our results show that the static case corresponds to a limit case of null rise time and infinite rupture velocity. Both parameters contribute in shifting the arrival time, but maximum runup may be affected by very slow ruptures and long rise time. Parametric analysis reveals that runup is strictly decreasing with the rise time while is highly amplified in a certain range of slow rupture velocities. For even lower rupture velocities, the <span class="hlt">tsunami</span> excitation vanishes and for larger, quicker approaches to the instantaneous case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH21A3827C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH21A3827C"><span>When is a <span class="hlt">Tsunami</span> a Mega-<span class="hlt">Tsunami</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chague-Goff, C.; Goff, J. R.; Terry, J. P.; Goto, K.</p> <p>2014-12-01</p> <p>The 2004 Indian Ocean <span class="hlt">Tsunami</span> is commonly called a mega-<span class="hlt">tsunami</span>, and this attribute has also been linked to the 2011 Tohoku-oki <span class="hlt">tsunami</span>. However, since this term was first coined in the early 1990's there have been very few attempts to define it. As such it has been applied in a rather arbitrary fashion to a number of <span class="hlt">tsunami</span> characteristics, such as wave height or amplitude at both the source and at distant locations, run-up height, geographical extent and impact. The first use of the term is related to a <span class="hlt">tsunami</span> <span class="hlt">generated</span> by a large bolide impact and indeed it seems entirely appropriate that the term should be used for such rare events on geological timescales. However, probably as a result of media-driven hyperbole, scientists have used this term at least twice in the last decade, which is hardly a significant portion of the geological timescale. It therefore seems reasonable to suggest that these recent unexpectedly large events do not fall in the category of mega-<span class="hlt">tsunami</span> but into a category of exceptional events within historical experience and local perspective. The use of the term mega-<span class="hlt">tsunami</span> over the past 14 years is discussed and a definition is provided that marks the relative uniqueness of these events and a new term, appropriately Japanese in origin, namely that of souteigai-<span class="hlt">tsunami</span>, is proposed. Examples of these <span class="hlt">tsunamis</span> will be provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080004415','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080004415"><span>Reliability <span class="hlt">model</span> <span class="hlt">generator</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cohen, Gerald C. (Inventor); McMann, Catherine M. (Inventor)</p> <p>1991-01-01</p> <p>An improved method and system for automatically <span class="hlt">generating</span> reliability <span class="hlt">models</span> for use with a reliability evaluation tool is described. The reliability <span class="hlt">model</span> <span class="hlt">generator</span> of the present invention includes means for storing a plurality of low level reliability <span class="hlt">models</span> which represent the reliability characteristics for low level system components. In addition, the present invention includes means for defining the interconnection of the low level reliability <span class="hlt">models</span> via a system architecture description. In accordance with the principles of the present invention, a reliability <span class="hlt">model</span> for the entire system is automatically <span class="hlt">generated</span> by aggregating the low level reliability <span class="hlt">models</span> based on the system architecture description.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43B1851L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43B1851L"><span>Evaluation of <span class="hlt">Tsunami</span> Hazards in Kuwait from Possible Earthquake and Landslide Sources considering Effect of Natural Tide</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Latcharote, P.</p> <p>2016-12-01</p> <p>Kuwait is one of the most important oil producers to the world and most of population and many vital facilities are located along the coasts. However, even with low or unknown <span class="hlt">tsunami</span> risk, it is important to investigate <span class="hlt">tsunami</span> hazards in this country to ensure safety of life and sustain the global economy. This study aimed to evaluate <span class="hlt">tsunami</span> hazards along the coastal areas of Kuwait from both earthquake and landslide sources using numerical <span class="hlt">modeling</span>. <span class="hlt">Tsunami</span> <span class="hlt">generation</span> and propagation was simulated using the two-layer <span class="hlt">model</span> and the TUNAMI <span class="hlt">model</span>. Four cases of earthquake scenarios are expected to <span class="hlt">generate</span> <span class="hlt">tsunami</span> along the Makran Subduction Zone (MSZ) based on historical events and worst cases possible to simulate <span class="hlt">tsunami</span> propagation to the coastal areas of the Arabian Gulf. Case 1 (Mw 8.3) and Case 2 (Mw 8.3) are the replication of the 1945 Makran earthquake, whereas Case 3 (Mw 8.6) and Case 4 (Mw 9.0) are the worst-case scenarios. <span class="hlt">Tsunami</span> numerical simulation was <span class="hlt">modelled</span> with mesh size 30 arc-second using bathymetry and topography data from GEBCO. Preliminary results suggested that <span class="hlt">tsunamis</span> <span class="hlt">generated</span> by Case 1 and Case 2 will impose very small effects to Kuwait (< 0.1 m) while Case 3 and Case 4 can <span class="hlt">generate</span> maximum <span class="hlt">tsunami</span> amplitude up to 0.3 m to 1.0 m after 12 hours from the earthquake. In addition, this study considered <span class="hlt">tsunamis</span> <span class="hlt">generated</span> by landslide along the opposite Iranian coast of Kuwait bay. To preliminarily assess <span class="hlt">tsunami</span> hazards, coastal landslides were assumed occurred at the volume of 1.0-2.0 km3 at three possible locations from their topographic features. The preliminary results revealed that <span class="hlt">tsunami</span> <span class="hlt">generated</span> by coastal landslides could impose a significant <span class="hlt">tsunami</span> impact to Kuwait having maximum <span class="hlt">tsunami</span> amplitude at the Falika Island in front of Kuwait bay and Azzour power and desalination plant about 0.5 m- 1.1 m depending on landslide volume and energy dissipation. Future works will include more accuracy of <span class="hlt">tsunami</span> numerical simulation with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.722..265A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.722..265A"><span>Source of high <span class="hlt">tsunamis</span> along the southernmost Ryukyu trench inferred from <span class="hlt">tsunami</span> stratigraphy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ando, Masataka; Kitamura, Akihisa; Tu, Yoko; Ohashi, Yoko; Imai, Takafumi; Nakamura, Mamoru; Ikuta, Ryoya; Miyairi, Yosuke; Yokoyama, Yusuke; Shishikura, Masanobu</p> <p>2018-01-01</p> <p>Four paleotsunamis deposits are exposed in a trench on the coastal lowland north of the southern Ryukyu subduction zone trench. Radiocarbon ages on coral and bivalve shells show that the four deposits record <span class="hlt">tsunamis</span> date from the last 2000 yrs., including a historical <span class="hlt">tsunami</span> with a maximum run-up of 30 m in 1771, for an average recurrence interval of approximately 600 yrs. Ground fissures in a soil beneath the 1771 <span class="hlt">tsunami</span> deposit may have been <span class="hlt">generated</span> by stronger shaking than recorded by historical documents. The repeated occurrence of the paleotsunami deposits supports a tectonic source <span class="hlt">model</span> on the plate boundary rather than a nontectonic source <span class="hlt">model</span>, such as submarine landslides. Assuming a thrust <span class="hlt">model</span> at the subduction zone, the seismic coupling ratio may be as low as 20%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7302O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7302O"><span>Developing an event-tree probabilistic <span class="hlt">tsunami</span> inundation <span class="hlt">model</span> for NE Atlantic coasts: Application to case studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Omira, Rachid; Baptista, Maria Ana; Matias, Luis</p> <p>2015-04-01</p> <p>This study constitutes the first assessment of probabilistic <span class="hlt">tsunami</span> inundation in the NE Atlantic region, using an event-tree approach. It aims to develop a probabilistic <span class="hlt">tsunami</span> inundation approach for the NE Atlantic coast with an application to two test sites of ASTARTE project, Tangier-Morocco and Sines-Portugal. Only <span class="hlt">tsunamis</span> of tectonic origin are considered here, taking into account near-, regional- and far-filed sources. The multidisciplinary approach, proposed here, consists of an event-tree method that gathers seismic hazard assessment, <span class="hlt">tsunami</span> numerical <span class="hlt">modelling</span>, and statistical methods. It presents also a treatment of uncertainties related to source location and tidal stage in order to derive the likelihood of <span class="hlt">tsunami</span> flood occurrence and exceedance of a specific near-shore wave height during a given return period. We derive high-resolution probabilistic maximum wave heights and flood distributions for both test-sites Tangier and Sines considering 100-, 500-, and 1000-year return periods. We find that the probability that a maximum wave height exceeds 1 m somewhere along the Sines coasts reaches about 55% for 100-year return period, and is up to 100% for 1000-year return period. Along Tangier coast, the probability of inundation occurrence (flow depth > 0m) is up to 45% for 100-year return period and reaches 96% in some near-shore costal location for 500-year return period. Acknowledgements: This work is funded by project ASTARTE - Assessment, STrategy And Risk Reduction for <span class="hlt">Tsunamis</span> in Europe. Grant 603839, 7th FP (ENV.2013.6.4-3 ENV.2013.6.4-3).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.U13A0013F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.U13A0013F"><span><span class="hlt">Tsunamis</span> triggered by the 12 January 2010 Earthquake in Haiti</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fritz, H. M.; Hillaire, J. V.; Molière, E.; Mohammed, F.; Wei, Y.</p> <p>2010-12-01</p> <p>. Field observations, video recordings, satellite imagery and numerical <span class="hlt">modelling</span> are presented. The team interviewed numerous eyewitnesses and educated residents about the <span class="hlt">tsunami</span> hazard. Community-based education and awareness programs are essential to save lives in locales at risk from locally <span class="hlt">generated</span> <span class="hlt">tsunamis</span>. Petit Paradis landslide scar with tree located 70m offshore</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911936M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911936M"><span>The 1887 earthquake and <span class="hlt">tsunami</span> in the Ligurian Sea: analysis of coastal effects studied by numerical <span class="hlt">modeling</span> and prototype for real-time computing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Monnier, Angélique; Gailler, Audrey; Loevenbruck, Anne; Heinrich, Philippe; Hébert, Hélène</p> <p>2017-04-01</p> <p>The February 1887 earthquake in Italy (Imperia) triggered a <span class="hlt">tsunami</span> well observed on the French and Italian coastlines. <span class="hlt">Tsunami</span> waves were recorded on a tide gauge in the Genoa harbour with a small, recently reappraised maximum amplitude of about 10-12 cm (crest-to-trough). The magnitude of the earthquake is still debated in the recent literature, and discussed according to available macroseismic, tectonic and <span class="hlt">tsunami</span> data. While the <span class="hlt">tsunami</span> waveform observed in the Genoa harbour may be well explained with a magnitude smaller than 6.5 (Hébert et al., EGU 2015), we investigate in this study whether such source <span class="hlt">models</span> are consistent with the <span class="hlt">tsunami</span> effects reported elsewhere along the coastline. The idea is to take the opportunity of the fine bathymetric data recently synthetized for the French <span class="hlt">Tsunami</span> Warning Center (CENALT) to test the 1887 source parameters using refined, nested grid <span class="hlt">tsunami</span> numerical <span class="hlt">modeling</span> down to the harbour scale. Several source parameters are investigated to provide a series of <span class="hlt">models</span> accounting for various magnitudes and mechanisms. This allows us to compute the <span class="hlt">tsunami</span> effects for several coastal sites in France (Nice, Villefranche, Antibes, Mandelieu, Cannes) and to compare with observations. Meanwhile we also check the computing time of the chosen scenarios to study whether running nest