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Tsunami modelling is widely used to estimate the potential impacts of tsunamis. Models require a tide input, which can be either static, representing a specific tide level, such as Highest Astronomic Tide or dynamic, which represents a moving tide level. Although commonly used, static tide inputs do not account for tsunami–tide interactions, which are known to be non-linear and more significant in estuaries when compared to the open coast. To demonstrate the differences between tsunami models using static or dynamic tide inputs, a series of models were carried out for two New South Wales estuaries, Sydney harbour and port hacking. Model boundary conditions phased a MW 9.0 Puysegur source tsunami with multiple tide scenarios. Fourteen distinct scenarios with dynamic tides were created by phasing the largest tsunami wave peak at regular intervals across the tidal range. For comparison, static tide models were run using equivalent tide levels. The situations where static tide models provide results comparable or more conservative than dynamic tide models are for the first 1–2 h after tsunami arrival, at high tides, and when compared to dynamic falling tides at the same tide level. Differences are most apparent upriver of geomorphological constrictions. The effects of geomorphological constrictions were further examined using idealised model setups with a constriction variable. Results show that constrictions affect downriver maximum water levels, tsunami wave heights, upriver water accumulation and inundation maxima and distributions. These results have implications for estuaries vulnerable to erosion at constriction sites during a tsunami event.

The 1783 Scilla landslide–tsunami (Calabria, southern Italy) is a well-studied event that caused more than 1500 fatalities on the beaches close to the town. This paper complements a previous work that was based on numerical simulations and was focused on the very local effects of the tsunami in Scilla. In this study we extend the computational domain to cover a wider portion of western Calabria and northeastern Sicily, including the western side of the Straits of Messina. This investigation focuses on Capo Peloro area (the easternmost cape of Sicily), where the highest tsunami effects outside Scilla were reported. Important tsunami observations, such as the wave height reaching 6 m at Torre degli Inglesi and flooding that reached over 600 m inland, have been successfully modeled but only by means of a high-resolution (10 m) topo-bathymetric grid, since coarser grids were inadequate for the purpose. Interestingly, the inundation of the small lake of Pantano Piccolo could not be reproduced by using today's coastal morphology, since a coastal dune now acts as a barrier against tsunamis. Historical analysis suggests that this dune was not in place at the time of the tsunami occurred and that a ground depression extending from the lake to the northern coast is a remnant of an ancient channel that was used as a pathway in Roman times. The removal of such an obstacle and the remodeling of the coeval morphology allows the simulations to reproduce the tsunami penetration up to the lake, thus supporting the hypothesis that the 1783 tsunami entered the lake following the Roman channel track. A further result of this study is that the computed regional tsunami propagation pattern provides a useful hint for assessing tsunami hazards in the Straits of Messina area, which is one of the most exposed areas to tsunami threats in Italy and in the Mediterranean Sea overall.

A tsunami is a significant coastal hazard that causes destructive damage to coastal cities in the world. Besides, tsunamis, generated on the west coast of Japan, damaged coastal cities on the east coast of Korea in 1983 and 1993. In recent years, there has been increasing interest in the potential tsunami zone near the west coast of Japan. Therefore, it is important to have tsunami observation instruments in proper locations for tsunami detection and warning aspect. This study proposes the optimal region for offshore tsunami observation instrument deployment under the limited condition that the tsunami source in out of the territorial sea by investigating areas with the highest tsunami detection probability along with maximum evacuation time and bottom slope. Using the Cornell Multi-grid Coupled Tsunami (COMCOT) numerical model and a probabilistic approach, this study suggests the optimal region for offshore tsunami detection instrument deployment to be the northeast area of Ulleung-do Island in the eastern sea of Korea.

Tsunami propagation over the entire Dayawan Bay was simulated using a 2D shallow water model to provide hydrodynamic boundary conditions for a 3D flow model, by which tsunami propagation inside the inlet of water-intake basin of the Dayawan Nuclear Power Plant (DNPP) was simulated. The 2D model covers the whole bay plus a little extension of the waters around the bay mouth. The sea side open boundary of the 2D model is generated from a superposition of an assumed tsunami process on a tide with exceedance probability of 10%. The event of encounter of a 10-min highest waters of the assumed tsunami process with such level of tide is estimated to be approximately a return period of 1490 years. Tsunami run-up in front of the revetment of the pump room was simulated using the 3D flow models. The rubble-mound breakwater was treated as porous medium in the simulation. Computational results of flow velocity indicate that tsunami propagation inside the basin is effectively prevented by the east breakwater. Computational results of waters in front of the revetment of the pump room indicate that the possible maximum water level is lower than the present elevation of the revetment, therefore the pump room has low risk of inundation.

Aoyama, Y.; Adityawan, M.B., Widiyanto, W., Mitobe, Y., Komori, D., and Tanaka, H., 2016. Numerical Study on Tsunami Propagation into a River. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1017 - 1021. Coconut Creek (Florida), ISSN 0749-0208. The Tohoku Earthquake and Tsunami in 2011 caused serious damage not only to coastal structures, but also to riverine infrastructure due to long distance of wave propagation into rivers located on the coast facing the Pacific Ocean. Although there have been numerous investigations on tsunami, limited number of studies have been made for tsunami propagation into a river channel. This study investigates tsunami propagation into a river numerically by comparing with laboratory experiment data. The present numerical simulation is based on shallow water equations, which are solved with the MacCormack sch...

The tsunami hazard for the coast of the Sea of Okhotsk requires a careful analysis, because this sea will be a zone of responsibility for the Tsunami Warning Service for the Far East coast of Russia. While it is not subject to such hazards on the part of seismogenic zones that can produce dangerous tsunamis, nevertheless the Sea of Okhotsk is open for penetration of tsunamis that can be produced by sources in other tsunamigenerating zones of the Kuril–Kamchatka region, as well as those of the entire Pacific Ocean. The tsunami hazard for the coast of the Sea of Okhotsk is examined here on the basis of historical observations and the results of numerical simulation for tsunami propagation from hypothetical rupture zones of near and distant earthquakes. It is shown that the real tsunami hazard can only emanate from those regional earthquakes with magnitudes 8.5 or greater that occur in the Kuril–Kamchatka seismogenic zone. Among the remote tsunamigenerating zones in the Pacific, the most dangerous locations are the rupture zones of mega-earthquakes of the class M9 that come from the South America zone and from Papua–New Guinea. These can produce water waves with amplitudes as great as 5 m along the entire coast of the Sea of Okhotsk.

The reliability of the narrative of the Biblical Exodus has been subject of heated debate for decades. Recent archaeological studies seem to provide new insight of the exodus path, and although with a still controversial chronology, the effects of the Minoan Santorini eruption have been proposed as a likely explanation of the biblical plagues. Particularly, it has been suggested that flooding by the associated tsunamis could explain the first plague and the sea parting. Recent modelling studies have shown that Santorini’s tsunami effects were negligible in the eastern Nile Delta, but the released tectonic stress could have triggered local tsunamigenic sources in sequence. This paper is aimed to a quantitative assessment of the potential role of tsunamis in the biblical parting of the sea. Several “best case” scenarios are tested through the application of a numerical model for tsunami propagation that has been previously validated. The former paleogeographic conditions of the eastern Nile Delta have been implemented based upon recent geological studies, and several feasible local sources for tsunamis are proposed. Tsunamis triggered by submarine landslides of 10–30 km3 could have severely impacted the northern Sinai and southern Levantine coasts but with weak effects in the eastern Nile Delta coastline. The lack of noticeable flooding in this area under the most favorable conditions for tsunamis, along with the time sequence of water elevations, make difficult to accept them as a plausible and literally explanation of the first plague and of the drowning of the Egyptian army in the surroundings of the former Shi-Hor Lagoon.

Due to the increasing activities of underwater earthquake along the Sulawesi's Waters past this one last decade, the development of future tsunami mitigation plan become important for Sulawesi Island. This research pin pointed to the easiness of the mitigation plan concept and the availability of the infrastructure. The development of this mitigation plan was based on future tsunami modeling of Manakarra Beach of Mamuju at West Sulawesi Province. TUNAMI N2 algorithm at SiTProS Ver 1.5 was used on the tsunami propagation modeling and based on Sulawesi Seismic System for tsunami generation. Tsunami run-ups and time impact interval as the modeling results, were used as basis to develop the tsunami mitigation plan for the Manakarra Beach. The evacuation scheme which put into map and module for the Manakarra Beach of Mamuju has been established in this research; with mainly based on a mass evacuation plan to the high buildings or high ground.

At least five catastrophic tsunami events have affected the Iberian Atlantic coasts during the last 7000 years. During this time, the former Gulf of Tartessos evolved towards the present marshland area, in the lower Guadalquivir valley (SW Spain). Ancient cultures flourished and vanished around this waterbody which, with its tidal dynamics, was an essential part of their living environment. A numerical modeling study on oceanographic conditions (tide and tsunami propagation) in the former Gulf of Tartessos has been carried out, in order to improve our insight on how they could have influenced the human activities in this area. The model solves the 2D depth-averaged hydrodynamic equations with appropriate initial and boundary conditions for tides and tsunamis. The model has been tested through simulation of tides under present bathymetry and of past tsunamis for which historical records exist. Then the bathymetry of the Gulf of Tartessos has been reconstructed for 2200 and 4000 years BP. The two main tidal semidiurnal and diurnal constituents have been simulated. Results indicate that they suffer a strong attenuation in the Gulf for both bathymetries, with significant currents only in its entrance. The known main active faults in the Gulf of Cadiz and the 1755 Lisbon source have been selected as case studies of tsunami propagation in the former Gulf of Tartessos. The 1755 Lisbon tsunami represented the worst case situation, and its numerical simulation has been subjected to several sensitivity tests. Results reveal negligible impacts for the inner shoreline of the Gulf of Tartessos, but severe damage could have been produced along the Atlantic coasts of SW Spain, from Cadiz to Huelva.

Results of a numerical simulation of the action of distant tsunamis on the coast of the Russian Far East are presented. It is shown that waves generated by focuses of the strongest M9 earthquakes in the region of South Chilean coast, as well as in the region of Papua New Guinea and Solomon Islands, are most dangerous for this coast. Other tsunamigenic zones of the Pacific Ocean, by virtue of their geographical position, orientation of focuses, and absence of pronounced channels (submarine ridges) along paths of tsunami propagation are not dangerous for it even at a limit magnitude of submarine subduction earthquakes. The simulation results are compared with historical data about manifestations of distant tsunamis on the Russian Far East coast.

The relations of river morphology and tsunami propagation in rivers were studied at several rivers in the Tohoku region during The Great Chilean Tsunami of 2010 and The Great East Japan Tsunami of 2011. It was found that river mouth morphological features play an important role in the intrusion of low magnitude tsunamis in which the geological and geographical conditions are an important factor. Nevertheless, the effects of these features were not found in the case of an extreme tsunami wave. As the wave enters the river, the propagation depends on other factors. It was found that the intrusion distance correlates well to the riverbed slope. The measurements of water level and riverbed slope were analyzed to propose an empirical method for estimating the damping coefficient for the tsunami propagation in rivers based on the tsunami of 2011. The proposed empirical method was used to approximate the length of the tsunami intrusion into a river by assuming that the furthest distance is given for the ratio of local tsunami wave height to the tsunami wave height at the river entrance of 0.05 (5 %). The estimated intrusion length from the proposed method in this study shows a good comparison with measurement data.

Accurate earthquake source parameters are essential input to tsunami hazard assessment and mitigation, including early warning systems. It is difficult to make accurate assumptions of earthquake source parameters where the tectonic setting is complex. To develop a better understanding of the relationship between tsunami impact and earthquake source, it is necessary to investigate variations in all parameters controlling the tsunami. This study investigates the sensitivity of earthquake source parameters in tsunami generation and propagation, with special focus on the Eastern Mediterranean. Our analysis shows that, given the difficulty in accurately determining all focal mechanism parameters, tsunami hazard studies should look at a range of parameters, taking into consideration the maximum generated tsunami. If this broad study scope is not possible due to computational limitations, at least sensitivity studies, such as presented here, should be conducted, and parameters should be selected that would lead to maximum tsunami generation. An option would be to consider only strike and rake variations in the scenario databases as the key criteria in determining the worst-case scenario for a given forecast point.

Summary For implementation of a regional Tsunami Early Warning System (EWS) in Sumatra island in Indonesia, a set of detailed and accurate tsunami propagation and flooding models using Delft3D were developed. The purpose of the models was not only to reproduce the 2004 Indian Ocean tsunami, but also to determine tsunami flood hazard maps with different return periods. The model outputs have then been used to build a tsunami flooding database covering 1250 hypothetical sources for different earthquake parameters along the Sunda Trench for an EWS called RiskMap. The model simulations produced detailed information of near-shore tsunami wave height, tsunami inundation length and run-up. Smart storage of computational results, in a geo-referenced database, allows quick access to the requisite information. The result is a system capable of issuing a warning within few minutes after a detection of an earthquake. The system has been successfully installed and tested in the last two years at national and regional emergency coordination centres, National Agency for Meteorology, Climatology and Geophysics (BMKG) and at Tsunami Disaster Mitigation Research Centre (TDMRC) in Banda Aceh.

A numerical model to simulate tsunami propagation in south of Iberia waters has been developed. It is based on the 2D non-linear hydrodynamic equations and allows calculating tsunami run-ups. The model has been validated through the simulation of historical tsunamis. Then it is applied to a risk assessment study to evaluate tsunami flooding along the Spanish and Moroccan coasts. A spectral analysis of tsunami waves has also been carried out. Finally, the model has been applied to simulate tsunami propagation in the former Gulf of Tartessos, where the city of the same name could have been located. The objective consists of evaluating if a large tsunami could have destroyed it, as some historians suggest.

A recent revision of the catalogue of tsunamis in Portugal has shown that Tagus estuary has been affected by catastrophic tsunamis numerous times over the past two millennia. This justifies the modelling efforts aimed at quantifying potential inundation areas for present-day altimetry and bathymetry of Tagus estuary. The purpose of this work is to present a 2DH mathematical model applicable to discontinuous shallow flows over complex geometries such as tsunami propagation overland. The conceptual model and the discretization scheme are presented and validation tests are described. The propagation of a tsunami with the magnitude of that of 1755 is simulated for the bathymetric and altimetry conditions of present day Tagus estuary. The study shows that some locations of Tagus estuary are vulnerable to tsunami impacts, as they may register 1 to 2m flow depths and velocities of 5ms–1.

A set of echograms obtained during the course of the Pacific Transects project in the second half of 1980 was digitized with a similar step within a distance of 1 mile. Based on the processing of these materials, the spectral and statistical characteristics of the irregularities of the bottom topography of the Northwestern Pacific were obtained. It was shown that the decrease of the spectral density within the wavelength range from 2 to 100 miles is well consistent with the k−2 law with the subdivision of the spectrum into two ranges: the small-scale (2–8 miles long and 50 m high) and medium-scale (10–40 miles long and 120 m high) ones. The dampening decrement of the tsunami wave due to the interaction with the irregularities of the bottom topography accounted for γ = 0.2 hr−1 for the forward scattering and 0.1 hr−1 for the back scattering. The forward scattering provides the transformation of the initial single pulse into the wave train, the delay of the maximum wave with respect to the arrival time of the tsunami, and the increase in the duration of the oscillations.

The East Japan tsunami of 11 March 2011 propagated more than 100 km upstream in the Columbia River. Visual analysis of its records along the river suggests that the tsunami propagation was strongly affected by tidal conditions. A numerical model of the lower Columbia River populated with tides and a downstream current was developed. Simulations of the East Japan tsunami propagating up the tidal river reproduced the observed features of tsunami waveform transformation, which did not emerge in simulations of the same wave propagating in a quiescent-state river. This allows us to clearly attribute those features to nonlinear interaction with the tidal river environment. The simulation also points to possible amplification of a tsunami wave crest propagating right after the high tide, previously deduced from the recordings of the 1964 Alaska tsunami in the river.

The tsunami generated by the 1 November, 1755 earthquake off the coast of Portugal affected mainly the coastlines of the Iberian Peninsula and Northwest Morocco, but was also observed in some places along the North Atlantic coasts. To determine whether the event could have effected the French coastline, we conducted a study to search for signs of the tsunami in historical records from all tide gauge stations off the French Atlantic coast during the twentieth century, specifically for the 28 February, 1969 and the 26 May, 1975 tsunamis that were recorded by the Portuguese tide gauge network. Because many recordings are available in La Rochelle (located on the southwest coast of France), we focused our study on this harbor. The analysis of the tide gauge data shows no evidence for tsunamis in La Rochelle, neither in 1969 nor in 1975. To confirm this lack of tsunami signals, we used nonlinear, shallow water equations to compute the tsunami propagation to the French Atlantic coastline for both 1969 and 1975 events. Results obtained from these simulations confirm otherwise unnoticeable wave amplitudes at La Rochelle harbor. In a second step, tsunamis from three different scenarios for the 1755 earthquake were modeled to estimate the impact of such a tsunami on the French Atlantic coast, with a focus on La Rochelle harbor. A comparison of the functions of tide configuration was made in order to analyse the difference in impact. The results show that, while the harbor is poorly impacted, several areas (western part of the island of Re and northern coast of the island of Oleron) may have experienced a moderate impact from 0.5 to 1 m, especially since the tide was high at the time of arrival, possibly causing local inundations in lowland areas.

The role of bottom friction in the runup of nonbreaking long waves on the shore is analyzed. The case of the normal incidence of monochromatic waves is considered. The relief of the model region consists of an even horizontal bottom area conjugated with a flat slope. The energy dissipation is estimated as the work of bottom friction forces over the wave field obtained using the known analytical solution based on the Carrier-Greenspan transforms. Estimates of energy losses for waves whose periods are typical for tsunami waves have been obtained. The energy dissipation is shown to be not concentrated in the shore line area as a rule. The question about the practicability of using partially reflecting boundary conditions on the coast to take into account the bottom friction in large-scale models of tsunami propagation is considered.

The effect of bathymetry near the south sea area of Korea on the propagation of 2011 East Japan Tsunami is analyzed based on the numerical simulation using the finite difference dispersion-correction model. It is found that the bathymetry from the source to Korean Peninsula, such as Nankai Trough, Ryukyu Islands and the topographical lens in the East China Sea, plays an important role to reduce the tsunami height along the south coast of Korea. The mechanism involved in the transformation of tsunamis over those topographies is discussed.

While in recent years much attention has been focused on tsunamis in the Indian Ocean, generated near Indonesia, equally destructive tsunamis also could occur in the western part of the North Indian Ocean. Specifically, the last major tsunami in the Arabian Sea occurred in November 1945 due to an earthquake that originated in the Makran region. The Tunami N2 model was used to simulate numerically the tsunami propagation, run-up, and inundation on the southwest coast of India and selected locations in the Lakshadweep islands in the Arabian Sea. The simulations show that the run-up due to the 1945 Makran tsunami along the southwest coast of India and Lakshadweep islands was considerably less than that of the 2004 Sumatra tsunami.

The Sumatra-Andaman arc is an active subduction zone that has generated several destructive tsunamis. The December 26, 2004, Sumatra-Andaman earthquake of magnitude Mw∼9.3 generated the most destructive tsunami known to man. The sustained high water level in several regions on the east coast of India due to tsunamis in the Bay of Bengal can be attributed to the reflection of direct tsunami waves and trapping of wave energy. In this paper we have simulated two scenarios of tsunamigenic earthquakes, the 2004 Sumatra earthquake and a possible great earthquake in the Andaman region. Tsunami wave propagation and inundation at Visakhapatnam due to these two earthquakes have been modeled. We find that the tsunami run-up heights for the 2004 Sumatra earthquake were about 1.5 m. For the other possible scenario, we observed that the run-up is about 3–4.6 m. The inundated distances have been estimated and are 1–2 km.

Environmental Modelling & Software, pp. online, 2010; International audience; A numerical simulation of the 26th December 2004 Indian Ocean tsunami for the entire coast of Sri Lanka is presented. The simulation approach is based on a fully nonlinear Boussinesq tsunami propagation model and a robust coseismic source. The simulation is first confronted to available measured wave height. The agreement between observations and the predicted wave heights allowed a reasonable validation of the simulation. As a result a synoptic picture of the tsunami impact is provided over the entire coast of Sri Lanka. It is found that amplification due to shoaling applies mainly in the Eastern and Southern coast because, here, the wave is propagating across the sea floor slope, while propagating along the slope for the Western coast. Spots of high waves are due to wave focusing in some coastal areas while local submarine canyons in other areas inhibit the wave amplification.

Tsunamis are frequent events in modern marine environments but evidence of their passing in subtidal ancient epicontinental sea deposits is elusive. It has been suggested that this is due to mis-identification or poor preservation potential. Herein a numerical modelling approach is used to show that tsunami propagation in one large ancient epicontinental sea was hindered by the damping effect of shallow bathymetries and reflection, refraction and diffraction from emergent landmasses. The Imperial College Ocean Model (ICOM) is used for this study and is first validated against data from the Sumatra–Andaman Tsunami of December 2004. A palaeobathymetric dataset is then presented for the Hettangian (Lower Jurassic) Laurasian Seaway with idealised tsunami sources situated on the continental shelf and within the adjacent oceanic basin. Results show that tsunamis forced from within ocean basins adjacent to the epicontinental sea are rapidly attenuated over the continental slope and fail to propagate great distances onto the shelf. Similarly, the sedimentological effect of tsunamis forced from within the epicontinental sea is also restricted. It is concluded that tsunami deposits in ancient epicontinental seas are most likely to occur in relative proximity to the source region and this must contribute to their scarcity in the geological record.

Instrumental data on the tsunami registration on Sakhalin and Hokkaido islands are presented. The numerical simulation of the tsunami propagation in the Tatar Strait was performed. The results of the calculations are in satisfactory agreement with the observed data.

This paper studies extreme tsunami scenarios in the South China Sea potentially originated from a giant rupture along the Manila Trench. Tsunami height and arrival time to the major coasts along the SCS are computed using TUNAMI-N2-NUS model. Sensitivity of tsunami parameters to the rupture properties is explored numerically. For tsunami waves potentially originated from the Manila Trench, it is shown that the Sunda Shelf and the Natuna Islands may act as a natural barriers, sheltering southwest part of the South China Sea and Singapore Strait.

The catastrophic tsunami of December 26, 2004 in Southeast Asia revealed the necessity of creating tsunami early warning systems in the regions of the World Ocean where these systems are still absent but the potential hazard of tsunami generation exists. The Black Sea is one of these regions. We present the general characteristic of the tsunami hazard in the Black-Sea region and describe the most probable zones of tsunami generation, the specific features of tsunami propagation, and the parameters of tsunamis according to the data of observations and the results of numerical simulations. We also discuss the possibility of tsunami early warning on the basis of the operative data provided by the network of hydrometeorological and seismological observation stations existing in this region.

On November 15, 2006, at 11:14 UTC, one of the strongest tsunamigenous earthquakes occurred near the Russian coast in the region of the Central Kuril Islands. Its magnitude was M w = 8.3, and the epicenter was located on the island slope of the deep Kuril–Kamchatka Trench 90 km southeast of Simushir Island (Fig. 1). The earthquake generated a tsunami that was manifested over the entire Pacific Ocean and was recorded with high accuracy by numerous coastal pressure gauges and by a large number of deep-water stations located in the open part of the ocean. The tsunami of 2006 became the strongest event of such type observed in the Pacific Ocean over the last 42 years (after the strongest Alaska tsunami in 1964). It occurred less than two years after the catastrophic December 26, 2004, earthquake and tsunami in the Indian Ocean, which caused unprecedented destruction and victims. However, it stimulated a drastic intensification in tsunami research [1, 2]. The November 15, 2006, earthquake and tsunami are unique because the possibility of their occurrence in the Central Kuril Islands region was predicted [1, 3, 4] and the possible scenarios of tsunami propagation were modeled [5, 6].

After the devastating Indian Ocean 2004 Tsunami, coastal economies around the Indian Ocean have been reminded of the necessity to make well-coordinated efforts to deal with the tsunami problem. An integrated socio-technological infrastructure has to be built, with key tasks including advanced sensors, reliable communication networks, fast predictive algorithms, early warning systems, and educational outreach. This paper highlights the key features of a prediction system under development in Singapore in support of the early warning system being developed in the region.

Focusing on the scattering of tsuanmi energy by the seamounts, this study aims to discuss the effect of Emperor seamounts on the tsunami propagation of the 2006 Kuril Island tsunami, using a finite difference method. The model results suggest that the contribution of Emperor seamounts on the maximum tsunami energy along the Pacific coast of Japan is as much as 50 % or more. Also, the spectral analysis of the observed tsunami records in Japan indicates that the scattering waves from Kinmei seamount dominate the wave components of 8-20 minutes in its wave period, which is consistent with the theory of Longuet-Higgins (1967).

To better understand the effects of river flow and tidal stage on the propagation of realistic tsunami waves up large rivers, simulations of the Columbia River (United States) were carried out. The two-dimensional depth-averaged version of the advanced circulation model was used. The model was forced with open boundary tides, tidal potential, and river flow. Simulations without tsunami waves demonstrated excellent agreement with numerous tidal gauging stations in the domain. A Cascadia Subduction Zone earthquake and associated tsunami were then considered by prescribing a rapid temporal change in the bathymetric/topographic grid. The simulations were repeated over a wide range of river flow conditions and a wide range of tidal phases. In each simulation, the tsunami was characterized in terms of the variation of its amplitude with upriver distance, how much land was inundated, and its propagation speed up the estuary. Although river flow is a dominant mechanism in the Columbia River in terms of st...

Numerical models for flow problems must be adapted to a wide range of physical processes and a corresponding wide range of temporal and spatial scales. The large number of different models is thus not surprising because the models must be tailored to specific problem types. The design considerations presented here are aimed toward coastal ocean models. There are several fundamental choices that must be made: form of the equations, discretisation in time and space, and physics to include. Of these, choice of the specific finite element to use and advection scheme are two longstanding issues. Another pivotal issue is whether to satisfy mass continuity locally, in patches, and/or globally. The choices presented here result in a model that is applicable to a range of coastal problems from short time-scale tsunami propagation and runup, to long time-scale flows.

International audience; The impacts of tides on extreme tsunami propagation due to potential Nankai Trough earthquakes in the Seto Inland Sea (SIS), Japan, are investigated through numerical experiments. Tsunami experiments are conducted based on five scenarios that consider tides at 4 different phases, such as flood, high, ebb, and low tides. The probes that were selected arbitrarily in the Bungo and Kii Channels show less significant effects of tides on tsunami heights and the arrival times of the first waves than those that experience large tidal ranges in inner basins and bays of the SIS. For instance, the maximum tsunami height and the arrival time at Toyomaesi differ by more than 0.5 m and nearly 1 hr, respectively, depending on the tidal phase. The uncertainties defined in terms of calculated maximum tsunami heights due to tides illustrate that the calculated maximum tsunami heights in the inner SIS with standing tides have much larger uncertainties than those of two channels with propagating tides. Particularly in Harima Nada, the uncertainties due to the impacts of tides are greater than 50% of the tsunami heights without tidal interaction. The results recommend to simulate tsunamis together with tides in shallow water environments to reduce the uncertainties involved with tsunami modeling and predictions for tsunami hazards preparedness.