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Tsunami hazard in coastal areas susceptible to flooding, although reduced (in terms of probability of occurrence), may pose a high risk. Therefore, in these areas, a detailed evacuation planning of the affected population is required as a risk mitigation measure. The knowledge and enforcement of evacuation routes may reduce the population vulnerability, making it more resilient and reducing risk. This paper presents a GIS approach for modelling evacuation routes based on the optimal path search problem, of the graph theory, which is implemented on ArcCasper tool. The methodology proposed considers the elements involved in the evacuation process, the worst credible tsunami inundation scenario (hazard extent and travel time), the number of people that needs to be evacuated in different time scenarios, the safe areas or destination points of the evacuation routes, the roads network characteristics and finally the time available to evacuate. The knowledge of those elements allows predicting some possible outcomes of the evacuation, such as the arrival time of the evacuees to a shelter and the identification of congestion hot spots resulting from the application of a flocking model which simulates the path to be used by evacuees avoiding obstacles. The municipality of Cascais was used to test the methodology proposed in this study. Cascais is one of the largest urban centres located about 25 km west of Lisbon, Portugal, with a high density of infrastructure along the coastline whereby most of the population and economic activities are exposed to a tsunami. The results, presented in the form of maps, allow identifying the optimal evacuation routes as well as the unfeasible routes. This crucial information could be used to the evacuation optimization regarding the location of meeting points and vertical shelters as well as to improve the accessibility of the areas to be evacuated. [ABSTRACT FROM AUTHOR]

In the present paper an appropriate model for Sri Lanka to build Disaster resilience nation, by participatory approach introducing evacuation zones through Eco-technological integration is discussed. The study was conducted in Gandara and Devinuwara area which underwent the Tsunami tragedy in 2004. A field survey was conducted through a structured questioner to collect the data on Tsunami impact and elevation in the area of four bays in Gandara which were affected due to the tsunami. Locational data were collected using GPS techniques. Evacuation sites were demarcated in the outer skirt of the Tsunami hazard zone, considering the factors of elevation, road accessibility, availability of common places, such as temples, schools in coordination with the disaster management center and other stake holder institutions. This helped to develop simulation maps for the planning processes of tsunami evacuation programs to build community resilience. Levels of inundation due to 2004 tsunami in the affected areas were demarcated through a Digital Elevation Model and appropriate evacuation sites and routes were identified to fix sign boards to follow in case of a tsunami warning. An eco-touristic approach is strictly followed to maintain the sustainability of the site. People mobilization and training programs were initiated by cataloging the historical and cultural heritages, Natural resources, Local wisdom and knowledge of the people, etc. to convert the sites in to an eco-touristic zone. In the investigated areas, the flooded area was demarcated as 172,380 square meters and the average distance covered by the wave inside the land as 90 meters with a maximum of 530 meters. The sustainable evacuation shelters for the future Tsunami evacuation programs in Gandara and Devinuwara areas were identified in Purana Viharaya and Jayabhodhi Viharaya in Gandara, and Wawwa temple in Devinuwara. [ABSTRACT FROM AUTHOR]

Landslides falling into water bodies can generate impulsive waves, which are a type of tsunamis. The propagating wave may be highly destructive for hydraulic structures, civil infrastructure and people living along the shorelines. A facility to study this phenomenon was set up in the laboratory of the Technical University of Catalonia. The set-up consists of a new device releasing granular material at high velocity into a wave basin. A system employing laser sheets, high-speed and high-definition cameras was designed to accurately measure the high velocity and geometry of the sliding mass as well as the produced water displacement in time and space. The analysis of experimental data helped to develop empirical relationships linking the landslide parameters with the produced wave amplitude, propagation features and energy, which are useful tools for the hazard assessment. The empirical relationships were successfully tested in the case of the 2007 event that occurred in Chehalis Lake (Canada). [ABSTRACT FROM PUBLISHER]

At 12:02:56 a.m. Monday, November 14 2016 NZDT (11:02:56 a.m., November 13 2016 UTC) a magnitude 7.8 earthquake struck near Kaikōura on the north-eastern coast of the South Island of New Zealand. This earthquake caused a tsunami along New Zealand's east coast that was recorded on a number of sea level gauges. Outside of the Kaikōura region, north facing bays along Banks Peninsula were most affected by the tsunami. Of these, Little Pigeon Bay experienced extensive inundation and an unoccupied cottage was destroyed by the wave run-up. We report on the inundation extent and (inferred) flow directions at Little Pigeon Bay, including a study on temporal changes in the field evidence of this inundation. Preliminary modelling results indicate that the waves may have excited resonance in the bay. We also present results from inundation surveys of nearby, north-facing bays on Banks Peninsula. The excitation of resonance in Little Pigeon Bay provides an explanation for the more severe inundation and damage there in comparison to these nearby bays. [ABSTRACT FROM AUTHOR]

Yeom, G.-S.; Mizutani, N.; Hur, D.-S., and Lee, W.-D., 2017. Application of a modified estimation formula for collision force of deformed drifting containers under tsunami conditions. Damage from a tsunami can be divided widely into direct damage and indirect damage by drifting bodies owing to a run-up wave. Indirect damage attributable to freight containers, which play a major role in international trade, is a concern owing to the effect on international and domestic economic activities. Recently, Japan incurred tremendous damage from a tsunami that occurred after the 2011 Great East Japan Earthquake and recorded the greatest amount of economical loss and highest wave run up (40 m in the Ryori district of Ofunato City) historically (PIANC Marcom WG53, 2010). A previous study proposed an estimation formula for a collision force of a container at drift from a run-up tsunami, which comprises the impulse and momentum of the container and the added mass. In this study, a modification of the existing estimation formula for the collision force of a drifting container from a run-up tsunami was implemented, and its improvement was verified through a comparison between laboratory and numerical experiments. Additionally, the estimation formula was revised for application to a large deformed container, and its applicability under prototypical conditions was confirmed through a comparison with the verified numerical model. Finally, for practical use, a simplification of the estimation formula was applied. As a result, the simplified version of the estimation formula, which considers a large deformation, was shown to have a similar form as the original estimation formula, which did not consider a large deformation, although the influence of the added mass has decreased. [ABSTRACT FROM AUTHOR]

Large boulder accumulations have been observed on various coasts bordering the Mediterranean and have been associated with extreme wave events such as powerful storms or tsunamis. This study provides an in-depth analysis of 430 boulder deposits, located along a 3.5 km stretch of rocky coast situated on the SE of the Maltese Islands. It includes a geomorphometric analysis of the observed boulders and use of numerical modelling to estimate wave height required to initiate boulder movement. Comparisons of aerial imagery over a period of 46 years have made it possible to identify boulder movement that could only be attributed to storm waves, given that no local tsunamigenic event has been recorded over this time period. Positioned in the central Mediterranean, the Maltese Islands are exposed to potential tsunamis generated by seismic activity associated with the Malta Escarpment, and the Calabrian and Hellenic arcs. Although imprints from historic tsunami impact cannot be excluded, results indicate that the area is exposed to strong storm waves that are capable of displacing some of the very large boulders observed on site. [ABSTRACT FROM AUTHOR]

The tsunami caused by the 2011 off the Pacific coast of Tohoku Earthquake seriously damaged the Pacific coast of northeastern Japan. In addition to its direct disturbance, a tsunami can indirectly affect coastal pelagic ecosystems via topographical and environmental changes. We investigated seasonal changes in the phytoplankton community structure in Otsuchi Bay, northeastern Japan, from May 2011, which was 2 months after the tsunami, to May 2013. The phytoplankton species composition in May 2011 was similar to that observed in May 2012 and 2013. The present results are consistent with the dominant species and water-mass indicator species of phytoplankton in past records. These results suggest that there was no serious effect of the tsunami on the phytoplankton community in Otsuchi Bay. Community analysis revealed that two distinct seasonal communities appeared in each year of the study period. The spring-summer community was characterized by warm-water Chaetoceros species, and dinoflagellates appeared from May to September. The fall-winter community was characterized by cold neritic diatoms, which appeared from November to March. The succession from the spring-summer community to the fall-winter community took place within a particular water mass, and the fall-winter community appeared in both the surface water and the Oyashio water mass, suggesting that water-mass exchange is not the only factor that determines the phytoplankton community structure in Otsuchi Bay. [ABSTRACT FROM AUTHOR]

Tsunamis associated with the 2011 off the Pacific Coast of Tohoku Earthquake seriously disrupted the shallow marine ecosystem along a 2000 km stretch of the Pacific coast of Japan. The effects of the 2011 tsunamis on the soft-bottom benthic community have been relatively well studied in the intertidal zone, whereas tsunami effects on the subtidal benthos remain poorly understood. Here, we investigated populations of the world's largest spoon worm Ikeda taenioides (Annelida: Echiura: Ikedidae) in subtidal zone of Funakoshi Bay, Tohoku District, northeastern Japan. Subtidal scuba-diving surveys at two sites in the bay showed extremely long proboscises frequently extending from small holes in the sandy seafloor shortly before and soon after the tsunami disturbances. Based on morphological and molecular identification, the proboscises were revealed to be parts of I. taenioides. On 30 November 2011, 265 days after the tsunami event, many large-sized individuals with >1 m long proboscises were observed; these individuals were probably not derived from post-tsunami larval recruitment but more likely survived the tsunami disturbances. This is surprising because other sympatric megabenthos (e.g. spatangoid echinoids and venerid bivalves) and seagrass beds were almost completely destroyed (although they later recovered) by the tsunamis in this bay. The burrows of I. taenioides are known to be very deep (70-90 cm), which may have sheltered them from the impacts of the tsunamis. Our observations suggest that the effects of the 2011 tsunamis on benthos in soft sediments may differ depending on their burrowing depth. [ABSTRACT FROM AUTHOR]

Sendai Bay in northern Japan suffered serious damage from massive tsunamis generated by the 2011 off the Pacific coast of Tohoku earthquake. The physical disturbance caused by a tsunami may affect the coastal ecosystem, including the planktonic diatom community. We investigated seasonal changes in the diatom community structure at a coastal and an offshore station in Sendai Bay, from June 2011 (3 months after the tsunami) to April 2014. Diatom abundance increased at both stations during the spring. Sporadic increases were also recorded at the coastal station during the summer because of silicate input from river discharge. Seasonal succession of the diatom communities was similar at both the coastal and offshore stations. The onset of the spring bloom consisted mainly of Chaetoceros spp. when water temperatures were low. Subsequently, species such as Skeletonema costatum s.l. became dominant as salinity and nutrient concentrations decreased. Cell density decreased from summer into early winter. Leptocylindrus danicus became dominant in the summer, but was replaced by Thalassiosira cf. mala from autumn into winter. Redundancy analysis (RDA) showed that most of the variation in the diatom community could be explained by temperature, salinity, NO , NO , PO , and SiO. In addition, the occurrence of diatom species before the tsunami showed a similar pattern to that after the tsunami, suggesting that the tsunami did not have a serious impact on the diatom community in Sendai Bay. [ABSTRACT FROM AUTHOR]

There is a general lack of the understanding of tsunami wave interacting with complex geographies, especially the process of inundation. Numerical simulations are performed to understand the effects of several factors on tsunami wave impact and run-up in the presence of submarine gentle slopes and coastal cliffs, using an in-house code, named a Constrained Interpolation Profile (CIP)-based model in Zhejiang University (CIP-ZJU). The model employs a high-order finite difference method, the CIP method as the flow solver, utilizes a VOF-type method, the Tangent of hyperbola for interface capturing/Slope weighting (THINC/SW) scheme to capture the free surface, and treats the solid boundary by an immersed boundary method. A series of incident waves are arranged to interact with varying coastal geographies. Numerical results are compared with experimental data and good agreement is obtained. The influences of submarine gentle slope, coastal cliff and incident wave height are discussed. It is found that the rule of tsunami amplification factor varying with incident wave is affected by angle of cliff slope, and there is a critical angle about 45°. The run-up on a toe-erosion cliff is smaller than that on a normal cliff. The run-up is also related to the length of submarine gentle slope with a critical about 2.292 m in the present study. The impact pressure on the cliff is extremely large and concentrated, and the backflow effect is nonnegligible. Results of our work are in high precision and helpful in inversing tsunami source and forecasting disaster. [ABSTRACT FROM AUTHOR]

Damage to seagrass and seaweed beds caused by the huge tsunami of the Great East Japan Earthquake on 11 March 2011 was investigated in Matsushima Bay, Miyagi Prefecture, Japan, by comparing satellite images taken before the tsunami in November 2009 and after the tsunami in May 2011. The results showed that the tsunami destroyed 220 ha of seagrass and seaweed beds, from 320 ha in 2009 to 100 ha just after the tsunami. Zostera marina beds on the sandy and muddy bottom were rather severely damaged compared with brown seaweed beds of Sargassum horneri on the rocky substrate. Substrates of the beds and directions of the tsunami seem to be responsible for the magnitude of the damage to the beds. Maps of the spatial distributions of the beds before and after the tsunami can provide information for the restoration of seagrass and seaweed beds as natural infrastructures of coastal fisheries resources. [ABSTRACT FROM AUTHOR]

The recent deployment of highly sensitive seafloor magnetometers coinciding with the deep solar minimum has provided excellent opportunities for observing tsunami electromagnetic signals. These fluctuating signals (periods ranging from 10-20 min) are generally found to be within $$\pm$$ $$\sim$$ 1 nT and coincide with the arrival of the tsunami waves. Previous studies focused on tsunami electromagnetic characteristics, as well as modeling the signal for individual events. This study instead aims to provide the time-frequency characteristics for a range of tsunami signals and a method to separate the data's noise using additional data from a remote observatory. We focus on four Pacific Ocean events of varying tsunami signal amplitude: (1) the 2011 Tohoku, Japan event (M9.0), (2) the 2010 Chile event (M8.8), (3) the 2009 Samoa event (M8.0) and, (4) the 2007 Kuril Islands event (M8.1). We find possible tsunami signals in high-pass filtered data and successfully isolate the signals from noise using a cross-wavelet analysis. The cross-wavelet analysis reveals that the longer period signals precede the stronger, shorter period signals. Our results are very encouraging for using tsunami magnetic signals in warning systems. [ABSTRACT FROM AUTHOR]

Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of tsunamis. 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 km 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 tsunami generation and propagation models. Tsunami modeling 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, tsunami amplitudes are greatest along the northern Yucatán Peninsula. [ABSTRACT FROM AUTHOR]

In the historical period, the Eastern Mediterranean has been devastated by several tsunamis, the two most damaging were those of AD 365 and AD 1303, generated by great earthquakes of magnitude >8 at the Hellenic plate boundary. Recently, events of 6-7 magnitude have occurred in this region. As the French tsunami warning center has to ensure the warning for the French coastlines, the question has raised the possibility for a major tsunami triggered along the Hellenic arc to impact the French coasts. The focus is on the Corsica coasts especially, to estimate what would be the expected wave heights, and from which threshold of magnitude it would be necessary to put the population under cover. This study shows that a magnitude 8.0 earthquake nucleated along the Hellenic arc could induce in some cases a tsunami that would be observed along the Corsica coasts, and for events of 8.5 magnitude amplitudes exceeding 50 cm can be expected, which would be dangerous in harbors and beach areas especially. The main contribution of these results is the establishment of specific thresholds of magnitude for the tsunami warning along the French coasts, 7.8 for the advisory level (coastal marine threat with harbors and beaches evacuation), and 8.3 for the watch level (inland inundation threat) for tsunamis generated along the Hellenic arc. [ABSTRACT FROM AUTHOR]

This study constitutes a preliminary assessment of probabilistic tsunami inundation in the NE Atlantic region. We developed an event-tree approach to calculate the likelihood of tsunami flood occurrence and exceedance of a specific near-shore wave height for a given exposure time. Only tsunamis 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 models for seismic sources, tsunami numerical modeling, 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 tsunamis. This paper illustrates a methodology through a case study, which is not an operational assessment. [ABSTRACT FROM AUTHOR]

Cook Strait Canyon is a submarine canyon that lies within ten kilometres of Wellington, the capital city of New Zealand. The canyon walls are covered with scars from previous landslides which could have caused local tsunamis. Palaeotsunami evidence also points to past tsunamis in the Wellington region. Furthermore, the canyon's location in Cook Strait means that there is inhabited land in the path of both forward- and backward-propagating waves. Tsunamis induced by these submarine landslides pose hazard to coastal communities and infrastructure but major events are very uncommon and the historical record is not extensive enough to quantify this hazard. The combination of infrequent but potentially very consequential events makes realistic assessment of the hazard challenging. However, information on both magnitude and frequency is very important for land use planning and civil defence purposes. We use a multidisciplinary approach bringing together geological information with modelling to construct a Probabilistic Tsunami Hazard Assessment of submarine landslide-generated tsunami. Although there are many simplifying assumptions used in this assessment, it suggests that the Cook Strait open coast is exposed to considerable hazard due to submarine landslide-generated tsunamis. We emphasise the uncertainties involved and present opportunities for future research. [ABSTRACT FROM AUTHOR]

This study evaluates tsunami hazards in the Marmara Sea from possible worst-case tsunami scenarios that are from submarine earthquakes and landslides. In terms of fault-generated tsunamis, seismic ruptures can propagate along the North Anatolian Fault (NAF), which has produced historical tsunamis in the Marmara Sea. Based on the past studies, which consider fault-generated tsunamis and landslide-generated tsunamis individually, future scenarios are expected to generate tsunamis, and submarine landslides could be triggered by seismic motion. In addition to these past studies, numerical modeling has been applied to tsunami generation and propagation from combined earthquake and landslide sources. In this study, tsunami hazards are evaluated from both individual and combined cases of submarine earthquakes and landslides through numerical tsunami 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 model with a two-layer model to conduct numerical tsunami simulations, and the numerical results show that the maximum tsunami 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 tsunami height for landslide-generated tsunamis from small, medium, and large of initial landslide volumes (0.15, 0.6, and 1.5 km, respectively) could reach 3.5, 6.0, and 8.0 m, respectively, along Istanbul shores. Possible tsunamis 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 tsunami amplitudes for small volumes significantly because of amplification within the same tsunami amplitude scale (3.0-4.0 m). Waveforms from all the coasts around the Marmara Sea indicate that other residential areas might have had a high risk of tsunami hazards from submarine landslides, which can generate higher tsunami amplitudes and shorter arrival times, compared to Istanbul. [ABSTRACT FROM AUTHOR]

One difficulty in developing numerical methods for tsunami modeling is the fact that solutions contain time-varying regions where much higher resolution is required than elsewhere in the domain, particularly when tracking a tsunami propagating across the ocean. The open source GeoClaw software deals with this issue by using block-structured adaptive mesh refinement to selectively refine around propagating waves. For problems where only a target area of the total solution is of interest (e.g., one coastal community), a method that allows identifying and refining the grid only in regions that influence this target area would significantly reduce the computational cost of finding a solution. In this work, we show that solving the time-dependent adjoint equation and using a suitable inner product with the forward solution allows more precise refinement of the relevant waves. We present the adjoint methodology first in one space dimension for illustration and in a broad context since it could also be used in other adaptive software, and potentially for other tsunami applications beyond adaptive refinement. We then show how this adjoint method has been integrated into the adaptive mesh refinement strategy of the open source GeoClaw software and present tsunami modeling results showing that the accuracy of the solution is maintained and the computational time required is significantly reduced through the integration of the adjoint method into adaptive mesh refinement. [ABSTRACT FROM AUTHOR]

Unlike probabilistic seismic hazard analysis (PSHA), there is not a well-established methodology for probabilistic tsunami hazard analysis (PTHA). The PTHA methodology presented is similar to the widely used PSHA methodology for ground motion, and incorporates both aleatory and epistemic uncertainty in calculating the probability of exceeding runup and drawdown values produced by tsunamigenic sources. Evaluating tsunami hazard is more difficult in locations such as the eastern coastline of Canada because of low tsunami recurrence rates and few historical examples. In this study, we evaluated the hazard from local and far-field earthquake and landslide tsunamigenic sources at a site on the Bay of Fundy in New Brunswick, Canada. These sources included local faults, the Puerto Rico subduction zone, fault sources in the Azores-Gibraltar plate boundary region, and landslides on the Canadian continental slope and in the Canary Islands. Using a new PTHA methodology that is closely linked to well-established PSHA methodology combined with tide stage probability, we calculated that the return period for a wave runup exceeding the tidal range of +4 m level above mean sea level (highest astronomical tide) is approximately 14,500 years. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Massive tsunami disturbances have potentially detrimental effects on genetic diversity and effective population size of coastal marine species, and evaluating these effects can be useful for devising conservation strategies for coastal marine environments. Local populations of the intertidal goby Chaenogobius annularis, which are distributed on scattered rocky beaches of the Japanese Archipelago, show demographic independence without overlapping generations, making this an ideal species with which to study the effects of tsunami disturbance on genetic diversity. Some of these populations were affected by the tsunami of the 2011 off the Pacific coast of Tohoku Earthquake. Here, we investigated the change in genetic diversity of a local population of this species, which was located close to the epicenter of the earthquake, across the cohorts before and after the tsunami and evaluated the impact of the tsunami disturbance. Genetic diversity was maintained after the tsunami, and no change in the effective population size was observed. Our results suggest that the tsunami disturbance has had no marked impact on the genetic diversity of C. annularis. [ABSTRACT FROM AUTHOR]

Copyright of Island Arc is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Island Arc is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Island Arc is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The 27th November 1945 tsunami generated due to an earthquake of magnitude of 8.1 ( $$M_{w}$$ ) in the Makran Subduction Zone (MSZ) is one of the most devastating tsunami in the Arabian sea. One of the prominent feature in the Arabian sea about 1700 km from the MSZ is the Lakshadweep Islands. Tsunamis generated in the MSZ would travel into the Arabian sea and would cause damage along the west coast of India and Lakshadweep Islands. In this paper Mathematical Simulation of the tsunami generation from this zone, its propagation into the Arabian sea and its impact on the Androth Island of Lakshadweep is studied using a Mathematical Model. The possible arrival time and the wave heights around different locations of the selected island have been quantified. Three different scenarios by changing fault parameters and manning coefficients are computed and the differences in the arrival time and tsunami wave amplitude in each case is observed. Results obtained is discussed and compared with the available tabulated information in literature. [ABSTRACT FROM AUTHOR]

Tsunamis and hurricanes cause a lot of damage to structures. The water-borne debris that is produced during these natural disasters can cause a considerable damage to the many structures if they have not been constructed for such loads. Tsunami field survey observations have indicated that the damage is aggravated by heavy objects like wooden logs, automobiles, boats, storage barrels and other containers. This paper presented the results of experimental study for the quantification of the debris impact force on the structures. Moreover, it studied the formulas, which have been specified in the recently published tsunamiresistant engineering design guidelines (FEMA P-646, 2012) and the Coastal Construction Manual (FEMA P-55, 2011) with the results of experiment. [ABSTRACT FROM AUTHOR]

This paper discusses possibilities to improve the Environmental Seismic Intensity Scale (ESI-07 scale), a scale based on the effects of earthquakes in the environment. This scale comprises twelve intensity degrees and considers primary and secondary effects, one of them the occurrence of tsunamis. Terminology and physical tsunami parameters corresponding to different intensity levels are often misleading and confusing. The present work proposes: i) a revised and updated catalogue of environmental and geological effects of tsunamis, gathering all the available information on Tsunami Environmental Effects (TEEs) produced by recent earthquake-tsunamis; ii) a specific intensity scale (TEE-16) for the effects of tsunamis in the natural environment at coastal areas. The proposed scale could be used in future tsunami events and, in historic and paleo-tsunami studies. The new TEE- 16 scale incorporates the size specific parameters already considered in the ESI-07 scale, such as wave height, run-up and inland extension of inundation, and a comprehensive and more accurate terminology that covers all the different intensity levels identifiable in the geological record (intensities VI-XII). The TEE-16 scale integrates the description and quantification of the potential sedimentary and erosional features (beach scours, transported boulders and classical tsunamites) derived from different tsunami events at diverse coastal environments (e.g. beaches, estuaries, rocky cliffs,). This new approach represents an innovative advance in relation to the tsunami descriptions provided by the ESI-07 scale, and allows the full application of the proposed scale in paleoseismological studies. The analysis of the revised and updated tsunami environmental damage suggests that local intensities recorded in coastal areas do not correlate well with the TEE-16 intensity (normally higher), but shows a good correlation with the earthquake magnitude (Mw). Tsunamis generated by earthquakes can then be considered efficient processes in the direct transference of the "energy" released by offshore seismogenic sources to the nearest coastal areas, even over distances of hundreds of kilometres (>200km). This scale, as the previous ones, is independent of the earthquake type (i.e. style of faulting) and only focuses on the environmental effects triggered by tsunamis of seismic origin. [ABSTRACT FROM AUTHOR]

Fossil shorelines produced by recent co-seismic movements were identified through a submarine survey along the coasts of Ithaca and Fiscardo (Greece). In both areas a tidal notch-slightly submerged below present Mean Sea Level (MSL) was observed at various sites. This "modern" notch is known to have been submerged by the global sea-level rise during the 19th and 20th centuries. The depth after tide and air-pressure correction of the vertex of the "modern" notch (that owes its submergence to the current rapid sea level rise) was measured between -20 and -30±5cm at Fiscardo and between -36 and -45±6cm at Ithaca. This "modern" notch at the same depth on east and west sides of the Ionian Thrust suggests that both areas were not affected by the co-seismic vertical movements that occurred in 1953 (in the wider area). On the other hand, a greater depth in Ithaca could be an effect of co-seismic subsidence. Over the long term, the tectonic behavior of Ithaca differs from Fiscardo. At Ithaca no evidence of emergence was found and Holocene vertical movements have been only of subsidence: submerged fossil tidal notches were distinguished below MSL at about -40 (modern), -60, -75, -95, -106, -126, -150 and -220±6cm. On the East coast of Fiscardo peninsula impacts of ancient earthquakes have left some marks of emergence at about +18 and +44±5cm, and of submergence at about -25 (modern), -45, -60, -75, -82, -100 and -230cm, with even some evidence of past uplift and subsidence at the same sites. [ABSTRACT FROM AUTHOR]

Natural disasters pose a threat to isolated populations of species with restricted distributions, especially those inhabiting islands. The Nicobar long tailed macaque.Macaca fascicularis umbrosus, is one such species found in the three southernmost islands (viz. Great Nicobar, Little Nicobar and Katchal) of the Andaman and Nicobar archipelago, India. These islands were hit by a massive tsunami (Indian Ocean tsunami, 26 December 2004) after a 9.2 magnitude earthquake. Earlier studies [Umapathy et al. 2003; Sivakumar, 2004] reported a sharp decline in the population of M. f. umbrosus after thetsunami. We studied the distribution and population status of M. f. umbrosus on thethree Nicobar Islands and compared our results with those of the previous studies. We carried out trail surveys on existing paths and trails on three islands to get encounter rate as measure of abundance. We also checked the degree of inundation due to tsunami by using Normalized Difference Water Index (NDWI) on landsat imageries of the study area before and after tsunami. Theencounter rate of groups per kilometre of M. f. umbrosus in Great Nicobar, Little Nicobar and Katchal was 0.30, 0.35 and 0.48 respectively with the mean group size of 39 in Great Nicobar and 43 in Katchal following the tsunami. This was higher than that reported in the two earlier studies conducted before and after the tsunami. Post tsunami, there was a significant change in the proportion of adult males, adult females and immatures, but mean group size did not differ as compared to pre tsunami. The results show that population has recovered from a drastic decline caused by tsunami, but it cannot be ascertained whether it has reached stability because of the altered group structure. This study demonstrates the effect of natural disasters on island occurring species. [ABSTRACT FROM AUTHOR]

On 11 March 2011, the Sanriku coast of Japan was struck by a massive tsunami associated with the 2011 off the Pacific coast of Tohoku Earthquake. The tsunami caused large disturbances in bottom sediments and severe destruction of human-made structures, natural landscapes and infrastructures such as sewage treatment systems and aquaculture facilities. A serious and continuing concern is a fundamental alteration of the nutrient regime in the impacted regions, which may exert a profound influence on the processes of ecosystem recovery and fishery reconstruction. We investigated the nutrient status of the water column of Otsuchi Bay, a small embayment that was heavily damaged by the tsunami. Our data collected between May 2011 and July 2014 revealed some prominent features in nutrient parameters that were potentially linked to effects of the tsunami. These features include (1) high turbidity and high concentrations of nitrite and silicic acid until September 2011, (2) the spread of seawater characterized by high phosphate concentration and low total inorganic nitrogen (ammonium + nitrate + nitrite) to phosphate (TIN/P) ratio during the mixing period between November 2011 and January 2012, and (3) an increase in the TIN/P ratio during the mixing period of subsequent years to become higher than it was before the earthquake. These data not only provide evidence of the alteration and subsequent recovery of the nutrient status of Otsuchi Bay after the earthquake but also suggest a possible tsunami-induced alteration in nutrient stoichiometry which appeared to last until at least the beginning of 2014. [ABSTRACT FROM AUTHOR]

A field study using satellite images was carried out to analyze the effect of coastal vegetation in mitigating the impact of a catastrophic tsunami on coastal villages in the Biobío Region, Chile, in February 2010. Two types of stand, Pinus radiata D. Don forests and Cupressus macrocarpa Hartw. shelterbelts, appear to have protected coastal areas behind them from the direct impact of the tsunami. The impacts of the horizontal and vertical structures of these coastal forests on the drag forces were analyzed by observing the characteristics of Pinus radiata forests and Cupressus macrocarpa shelterbelts. The stands absorbed the impact of the tsunami without incurring broken stems or uprooted trees due to their diverse horizontal structure, as they contained short trees with various diameters. However, small areas of the stands were damaged by salinity after the tsunami. For this tsunami, which was less than 3 m high, the horizontal and vertical structures of the P. radiata and C. macrocarpa stands provided effective protection for coastal villages since they reduced the velocity and height of the tsunami. A shelterbelt consisting of three rows of C. macrocarpa in front of the tsunami and a P. radiata forest with a density of 11 trees/100 m and a width of >50 m immediately behind the shelterbelt are suggested as a means of protecting communities along the coastline of the Biobío Region against tsunamis. [ABSTRACT FROM AUTHOR]

Maximum-recorded run-up estimates of six major nearfield paleotsunamis, dating from 0.3 to 2.8 ka, are compiled from reported studies at 12 reliable localities distributed over a north-south distance of 1000 km in the Cascadia subduction zone. The run-up estimates are based on surveyed elevations and positions of terminal sand sheet layers that were deposited by the dated paleotsunamis. Maximum terminal deposit elevations from open-coastal sites range from 3 to 12 m NAVD88. Paired proximal and distal run-up sites at four localities demonstrate landward vertical attenuation gradients (−2.5 to −4.2 m km) of decreasing terminal sand deposit elevation with increasing distance inland. An averaged attenuation gradient is reversed (3.0 m km) to project paleotsunami run-up elevations to adjacent ocean shorelines. The run-up projections are further adjusted by paleotsunami age and relative sea level curves to estimate shoreline inundation elevations under modern sea level conditions. The tsunami shoreline inundation elevations range from 3 ± 2 to 15 ± 2 m NAVD88, with the largest values occurring along the central Cascadia margin and the smallest values occurring in the eastern Juan de Fuca Strait. Contradictory to some numerical tsunami modeling assumptions, there is no apparent correlation between duration of interseismic strain accumulation or estimated upper-plate elastic flexure and corresponding paleotsunami run-up heights on the central Cascadia margin. The short duration since the last Cascadia megathrust rupture (0.3 ka) cannot be used to imply smaller run-up values for a near-future Cascadia tsunami. Coastal communities should plan for the maximum paleotsunami run-ups as recorded at the nearest reliable run-up localities. [ABSTRACT FROM AUTHOR]

This study represents a simple model for the changes calculation that coastal structure of the Adriatic and Jonian Sea may undergoes by a tsunami impact in the maritime dimension. In spite of the fact that the great majority of seismic tsunami is generated in ocean domains, smaller basins as the Adriatik and Ionian Sea sometimes experience this phenomenon. In this investigation we study the tsunami hazard associated with Adriatic and Ionian Sea fault system. The study has been carried out based on the coastal structure of Adriatic Sea, in the subsequent studies, that how this structure will affect on the tsunami wave. Tsunamis are one of the most destructive natural hazards that affect the coastal areas. Its waves are capable of destroying the objects on the coast and re-shaping the coastal geography, geomorphology and ecosystem. These waves have unusually long-wavelength in excess of 100 kms, generated in the open sea and transformed into a train catastrophic oscillations on the sea surface close to coastal zones. After the tsunami wave, the coastal structure undergoes some changes, and these changes will directly affect in the marine ecosystem. The sediment structure is formulated based on a previous approaching model built by Bruce E. Jaffe and Guy Gelfenbuam, 2007. (A. Daberdini, Rr. Ormeni, 2013).This calculation model is approached based on our coastal structure. The difference on the deposit granule size has more impact on the tsunami wave speed, rather than its thickness. The result of this study shows how to built an approximate model for the structuring that the Albanian coast may undergoes by the seismic activity, which in some cases may develop tsunami with marine dimension. The Physical structure may damaged by the force of the wave itself, physical removal of flora and fauna and increased sediment load which could kill sediment sensitive species and sea grasses by smothering. Chemical changes may included saltwater intrusion, eutrophication (enrichment) of the water resulting from increased runoff, raw sewage and decomposition of flora and fauna. Non biodegradable waste such as plastics may contribute to a buildup in marine debris. [ABSTRACT FROM AUTHOR]

Separated by continents and cultures, survivors of the Asian tsunami and Hurricane Katrina share a common bond in their extreme trauma and ensuing struggles. The authors discuss and illustrate core [...]

On 28 November 1945, in the Makran trench off Pakistan, a large earthquake (8.1 Mw) produced a tsunami that struck the coast of Oman and left a taphonomically distinct shell bed in Sur Lagoon. The shell bed was thick (5-25 cm) and laterally extensive, covering a >1 [km.sup.2] area. The shell assemblage from the deposit contained a mean of 59% for articulated bivalves of allochthonous offshore and subtidal species (e.g., Tellina palatam) as well as a mean of 20% for lagoonal species, indicating large-scale erosion and transport. Taphonomic traits (e.g., articulation, rounding, fragment angularity) of all bivalve material >5.6 mm were quantified for eight sample horizons, and compared with a tsunamite from Caesarea, Israel. Some of the taphonomic characteristics between the shell beds from these two different depositional settings were similar, and three tsunamigenic specific traits were identified: (1) thickness and lateral extent of the shell deposit, (2) presence of allochthonous articulated bivalves out of life position, and (3) extensive angular fragmentation. These results show that tsunamis form shell accumulations and cannot be ignored when assessing shell bed origin for the geological record. When these three traits are collectively found, a tsunamigenic origin should be considered for the shell bed. Keywords: tsunami, bivalve taphonomy, Oman, Sur Lagoon, Makran trench.

This paper considers an asset market subject to search frictions, where there are adjustment costs to the entry rate of buyers. An implication is that even in asset markets where the search frictions are very small, asset prices respond to changes in liquidity. Another implication is that asset liquidity is a state variable, the dynamics of which are analysed. I demonstrate that transition paths of liquidity to its (stable) steady state can exhibit dramatic divergence before convergence following small positive deviations in the measure of buyers in the market. Thus, adjustment costs of entry are a potential source of volatility by generating large waves of liquidity, or “tsunami”, in asset markets. I quantitatively assess the ability of the mechanism to generate asset market booms and busts via the implied price movements. [ABSTRACT FROM AUTHOR]

Historical reports from the 17th Century document two destructive tsunamis with run-ups exceeding 5 m, affecting proximal basins of Lake Lucerne (Switzerland). One event in ad 1601 is coeval with a strong nearby earthquake (MW ca 5·9) which caused extensive slope failures in many parts of the lake. The second event in ad 1687 is associated with an apparently spontaneous partial collapse of the Muota river delta. This study combines high-resolution bathymetry, reflection seismic and lithological data to document the sedimentary and morphological signatures of the two subaqueous mass movements that probably generated the observed tsunamis. Such mass movements are significant as a common sedimentation process and as a natural hazard in fjord-type lakes and similar environments. The deposits, covering large parts of the basins with thicknesses reaching >10 m, consist of two subunits: A lower 'massflow deposit' contains variably deformed sediments from the source areas. Its emplacement affected pre-existing sediments, incorporating thin sediment slices into the deposit and increasing its volume. Deep-reaching deformation near basin margins is expressed as bulges on the lake floor. An overlying 'megaturbidite', featuring a graded, sandy base and a thick homogeneous muddy part, was deposited from suspended particles. The source area for the ad 1601 event, gently dipping lateral slopes with an unconsolidated hemipelagic sediment cover, hosts a pronounced slide scar with sharp escarpments and sliding surfaces. The source area for the ad 1687 event on an active delta slope has been overprinted by continued sedimentation and does not show an unambiguous scar. The case studies are exemplary for end-member types of source areas (lateral versus delta slopes) and trigger mechanisms (seismic versus aseismic); they show that morphological mapping and reconstructions of past events are key components of a hazard assessment for mass movement-generated tsunamis. [ABSTRACT FROM AUTHOR]

Destructive solitary (tsunami) waves are capable of moving large amounts of coastal sediments and causing subsequent morphological changes in sandy beaches. Experimental studies can be significantly helpful to assess the process of sediment transport brought about by a tsunami. The present study is an experimental one that aims to investigate sediment transport and deformation of sandy beaches caused by tsunami waves. Waves were generated by a gate wave-producing system to simulate tsunami waves. Laboratory equipment and mounted cameras were applied to examine run-up and run-down processes of waves and the beach profile changes were drawn. The techniques of estimating the transport rate of sediment particles is based on the four traps set in different parts of the beach. The obtained results showed that waves were not capable of transporting the sediment in regions far from the coast where shoaling effects were not considerable. Furthermore, wave breaking point and its distance from each trap have significant effects on the sediment transport assessment of that region. Moreover, the achieved findings indicate that sediment transport that occurred in the run-down of the waves was more effective than that from run-up. [ABSTRACT FROM AUTHOR]

Catalán, P.A.; Cienfuegos, R., and Villagrán, M., 2014. Perspectives on the long-term equilibrium of a wave dominated coastal zone affected by tsunamis: The case of Central Chile. The capability to predict the long term evolution of coastal state parameters can be severely affected by neglecting major geomorphic forcings. Among these, the effect of tsunamis as been largely neglected along the Chilean coast. In this contribution, we present a qualitative and descriptive assessment of the sudden change induced by the tsunami on a coastal location in Central Chile, and the consequent recovery process. The latter is driven mostly by strong wave forcing, with a very fast recovery capactity. The necessity and consequences of including tsunamis in long term evaluations fo coastal morphology are briefly discussed. [ABSTRACT FROM AUTHOR]

Understanding the formation of tidal bores is of great importance to the changing morphology of estuaries. This study investigates how the slope of tidal bores front changes by influence of varying shape and depth in estuaries. A new analytical solution of the slope was derived from the 1D shallow water equation and two numerical models were developed based on the Upwind scheme and Superbee schemes to simulate the propagation of tidal waves. Six cases were utilized to investigate the influences of decreasing width and depth on the generation of tidal bores. Analytical results suggest that the initial depth is considered to have more significant influence on the generation of tidal bore than the initial width. Compared with the analytical results, Scheme 2, which is based on Superbee scheme, is found to be superior to the other scheme and its results show a good agreement with the new analytical solution. Both analytical and numerical results show that the decrease of width and depth can promote the generation of tidal bores. In contrast, tidal bores may weaken or even not form due to the energy dissipation bottom friction induced. [ABSTRACT FROM AUTHOR]

Brill, D.; Pint, A.; Jankaew, K.; Frenzel, P.; Schwarzer, K.; Vött, A., and Brückner, H., 2014. Sediment transport and hydrodynamic parameters of tsunami waves recorded in onshore geoarchives. In regions with a short historical tsunami record, the assessment of long-term tsunami risk strongly depends on geological evidence of prehistoric events. Whereas dating tsunami deposits is already well established, magnitude assessment based on remaining sedimentary structures is still a major challenge. In this study, two approaches were applied to deduce transport processes and hydrodynamic parameters of tsunami events from onshore deposits found in the coastal plain of Ban Bang Sak, SW Thailand: (1) The maximum offshore sediment source was determined using granulometry, geochemistry, mineralogy and foraminifera of the tsunamites, and reference samples from various marine and terrestrial environments, and (2) the onshore flow velocities and flow depths of associated tsunami waves were estimated by means of sedimentation modelling. In the case of the Indian Ocean tsunami (IOT) of 2004, modelled flow velocities of 3.7 to 4.9 m/s, modelled onshore flow depths of up to 5.5 m, and a sediment source from offshore areas shallower than a 45-m water depth-including littoral sediments transported as bedload and suspended load from the shallow subtidal zone-are in agreement with quotations based on survivor videos and posttsunami surveys. For a 500- to 700-year-old predecessor, comparable flow velocities and flow depths of 4.1 to 5.9 m/s and 4.0 to 7.5 m, respectively, were modelled, indicating a similar magnitude as the IOT 2004. Comparable values of maximum transport distance and depth of wave erosion were also found. In the case of three older tsunami candidates, dated to 1180 to 2000 cal BP, the deposits indicate partly similar source areas with water depths of less than 45 m and partly shallower source areas restricted solely to the beach. Whereas the former tsunamis are interpreted as events similar to 2004, the latter are more likely storms or tsunamis of a lower magnitude. [ABSTRACT FROM AUTHOR]

Natural catastrophes could damage island biodiversity and ecosystems, and their effects could become devastating if combined with human disturbances. In this study, we determined the effects of the tsunami occurred in Robinson Crusoe Island (Chile) on 27 February 2010 on an endangered soil-plant system. Using data of endemic Cabbage Trees ( Dendroseris litoralis Skottsb.) and soil attributes taken before and after the 2010 event, we developed thematic maps to assess the changes in population size and soil substrate of Cabbage Trees caused by the tsunami. We determined that from 153 pre-tsunami (2009) standing Cabbage Trees, only 66 (43 %) survived in 2011, mostly in elevations above 25 m a.s.l. Before the tsunami, 86 (56 %) of Cabbage Trees were established in humus-rich soil sites whereas after the tsunami, this number declined to 53 (35 %). These results represent the first report of a severe population decline after a tsunami and indicate that tsunamis are an important source of species extinction in small oceanic islands not only by reducing the population size but also by reducing the quality of sites for plant growth. [ABSTRACT FROM AUTHOR]

The massive 2004 Indian Ocean tsunami caused vast devastation along the coastal areas in countries around the Indian Ocean rim. Satellite images of various spatial resolutions could quickly capture the affected areas and were used for emergency response after the catastrophe occurred. To figure out the extent of affected areas, moderate-resolution satellites (e.g., Terra-ASTER) images are more suitable than high-resolution satellites (e.g., Ikonos) images. Basically, tsunami-affected areas can be observed and detected through land cover changes. Based on the nature of the tsunami attack, we chose the normalized difference vegetation index, soil index, and water index as indicators to help detect changes. This paper first investigates the fluctuations of these indexes and their differences using ASTER images of southern Thailand. The investigation is carried out in two cases: one using only the data acquired after the tsunami, and the other using both data acquired before and after the tsunami. Consequently, the thresholds of index differences are set up for the detection of tsunami-affected areas. In addition, since landform is a significant factor to determine the extent of tsunami runup, Shuttle Radar Topography Mission data are employed to perform geomorphological classification and to assess its relationship with the tsunami-affected areas. Index Terms--Landform classification, normalized difference vegetation index (NDVI) Terra-ASTER, the 2004 Indian Ocean tsunami, tsunami runup.