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On January 1 2024, at 16:10 JST, an earthquake of Mw 7.5 occurred underneath the Noto Peninsula of Ishikawa Prefecture, Japan. This event caused a cascading disaster impact on cities in the Noto Peninsula through a series of strong earthquake shakes, strong ground motions, slope failures, liquefaction, fire, and tsunamis. The tsunami first reached Suzu City a few minutes after the earthquake, eventually affecting approximately 340 km of the coast from the Ishikawa to Niigata Prefectures. The Coastal Engineering Committee of the Japan Society of Civil Engineers conducted an organized post-event field survey to understand the impact of tsunamis on land. This study summarizes the post-event field survey results and provides a general understanding of tsunami behavior and damage using measured tsunami inundation and run-up heights. [ABSTRACT FROM AUTHOR]

The overtopping-inundation process of a tsunami results in the collisions of drifting objects on the coast, which damage structures, thereby increasing the risk of collapse. This study conducted laboratory experiments on the collision between a drifting container caused by the overtopping-inundation process of a solitary wave and a fixed port crane's leg. The movement trajectory and velocity of the container as well as the collision velocity by solitary wave inundation, were analyzed using motion analysis software. Overall, increasing solitary wave scale, collision velocity, and drifting object weight and decreased distance between the two objects tended to increase the collision force. However, different experiment results were also obtained due to pitching in objects that fully floated without bottom friction owing to the solitary wave bore. This resulted in line-to-surface collisions. Thus, surface-to-surface contact occurred under the incomplete floating condition owing to the difficulty because of interference with the bottom; however, the collision force decreased under complete floating conditions owing to line-to-surface contact. Therefore, the contact condition according to the floating behavior must be considered a parameter while predicting the collision forces of drifting objects. Thus, surface-to-surface contact occurred under the incomplete floating condition owing to the difficulty because of interference with the bottom; however, the collision force decreased under complete floating conditions owing to line-to-surface contact. Therefore, the contact condition according to the floating behavior must be considered a parameter while predicting the collision forces of drifting objects. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to evaluate life safety risk of coastal communities vulnerable to seismic and tsunami hazards. The work explicitly incorporates two important aspects in tsunami evacuation modeling: (1) the effect of earthquake-induced damage to buildings on building egress time, (2) the effect of earthquake-induced debris on horizontal evacuation time. The city of Seaside, Oregon, is selected as a testbed community. The hazard is based on a megathrust earthquake and tsunami from the Cascadia Subduction Zone that was defined in a previous study. The built environment consists of buildings and the transportation network for the city. Fragility analysis is used to estimate the seismic damage to buildings and resulting debris that covers portions of the road network. The horizontal evacuation time is determined based on the shortest path to shelters, including the increased travel time due to the earthquake-generated debris. The effects of different mitigation strategies are quantified. Results indicate the fatality and life safety risk of a near-field tsunami increases by 4.2–8.3 times when the effects of building egress and earthquake-induced debris are considered. The choice of population layer affects the life safety risk and thus the maximum risk is obtained when daytime populations are considered. Use of mitigation strategies result in a significant decrease in the number of fatalities. For hazards with recurrence intervals larger than 500- to 1000-years, the seismic retrofit is comparable to vertical evacuation and an effective strategy in reducing fatalities and associated risks. Implementing all mitigation strategies reduces the life safety risk by 90%. [ABSTRACT FROM AUTHOR]

On January 1, 2024 at 16:10:09 JST, an Mj 7.6 earthquake struck the Noto Peninsula in the southern part of the Sea of Japan. This location has been experiencing an earthquake swarm for more than three years. Here, we provide an overview of this earthquake, focusing on the slip distribution of the mainshock and its relationship with the preceding swarm. We also reexamined the source areas of other large earthquakes that occurred around the Sea of Japan in the past and compared them with the Matsushiro earthquake swarm in central Japan from 1964 to 1968. The difference between the Matsushiro earthquake swarm and the Noto earthquake swarm is the surrounding stress field. The Matsushiro earthquake swarm was a strike-slip stress field, so the cracks in the crust were oriented vertically. This allowed fluids seeped from the depths to rise and flow out to the surface. On the other hand, the Noto area was a reverse fault stress field. Therefore, the cracks in the earth's crust were oriented horizontally. Fluids flowing underground in deep areas could not rise and spread over a wide area in the horizontal plane. This may have caused a large amount of fluid to accumulate underground, triggering a large earthquake. Although our proposed mechanism does not take into account other complex geological conditions into consideration, it may provide a simple way to explain why the Noto swarm is followed by a large earthquake while other swarms are not. [ABSTRACT FROM AUTHOR]

This paper develops a tsunami inundation model, filling the current void between industry applied simplified methods (bathtub and attenuation) and comprehensive numerical modeling. The proposed model utilizes two‐dimensional equations established on hydraulic principles (energy conservation and friction loss) to produce the finite‐difference, two‐dimensional model. While the sophistication of depth‐averaged numerical modeling has not been entirely replicated, the incorporation of hydraulic roughness and gravitational effects (slope) through the Bernoulli energy equation, accompanied by suitable assumptions, significantly improves performance over simplified bathtub and attenuation methods. This improvement not only retains excellent efficiency (completing case studies in under 100 s) but also yields inundation results comparable to traditional numerical modeling, which typically takes multiple hours to days. This is the first application of such equations to a two‐dimensional tsunami inundation model, leading to simulations at Gisborne and Christchurch, New Zealand, for validation against the numerical model, COMCOT. F1 scores produced from inundation extent comparisons were upwards of 84%. Inundation depth discrepancies recorded 77% within a ±$\pm$1 m range, while over 93% within a ±$\pm$2 m range. [ABSTRACT FROM AUTHOR]

The 1771 Meiwa tsunami which struck the southern Ryukyu Islands (Sakishima Islands) had greater than 22 m run-up height, leaving about 12,000 casualties in its wake. At many places, the tsunami inundation or lack of inundation is well recorded in historical documents. Several tsunami source models have been proposed for this event using historical records as constraints of tsunami calculations. Nevertheless, the source model remains under discussion. This study re-evaluated the tsunami wave source model of the 1771 Meiwa tsunami using high-resolution (10 m mesh) bathymetric and topographical data for tsunami calculation, the latest historical record dataset, and seismological knowledge. Results demonstrated that a tsunami earthquake along the southern Ryukyu Trench was the likely cause of the 1771 event. However, it is noteworthy that assumption of a large slip with 30 m is necessary for a shallow and narrow region (fault depth = 5 km, fault width = 30 km, Mw = 8.49) of the plate boundary in the Ryukyu Trench, which is far larger than previously thought. This requirement of very large initial water level change at the source might involve not only the fault rupture along the plate boundary but also deformation by splay faults, inelastic deformation of unconsolidated sediments near the trench axis, and/or giant submarine landslides. Results also show that the effects of fault parameters on the run-up were quite different depending on the offshore coral reef width. This phenomenon strongly constrained the fault width to 30 km. Our tsunami ray tracing analysis further revealed the effects of bathymetry on tsunami propagation. It is noteworthy that meter-long huge tsunami boulders tend to be distributed along the specific coasts at which the tsunami was concentrated by bathymetric effects. This finding suggests that past tsunamis, including the 1771 event, might have affected the specific coral reefs on Sakishima Islands repeatedly, which is crucially important for understanding the heterogeneous distribution of tsunami boulders. This feature might also be useful to elucidate the effects of large tsunamis on the corals and reefs because a direct comparison of coral reefs that are damaged and not damaged by tsunami waves is testable in narrow areas in the case of the Sakishima Islands. [ABSTRACT FROM AUTHOR]

In mining areas with high groundwater tables, mining subsidence can lead to the inundation of cropland by water, causing damage to cropland and posing a threat to national food security. The implementation of concurrent mining and reclamation techniques can effectively enhance the reclamation rate of cropland. This technique requires engineers to initiate reclamation measures before cropland waterlogging occurs. Therefore, when mining a panel underground, an accurate calculation of the time when cropland becomes waterlogged, known as the theoretical reclamation timing, is crucial. To address this issue, this study proposes a computational method for the theoretical reclamation timing of cropland under the conditions of single-panel mining based on intelligent optimization algorithms. In addition, this paper also proposes an optimization method for the theoretical reclamation timing of cropland within a district based on an intelligent optimization algorithm. Utilizing this method makes optimizing the layout of multiple panels possible, thereby delaying the theoretical reclamation timing for cropland within a district. This approach aims to shorten the duration of reclamation projects and minimize their interference with agricultural activities. Through experimental validation, this paper demonstrates the reliability of these two methods. This study is beneficial for the rational planning of reclamation projects. [ABSTRACT FROM AUTHOR]

Despite many discussions on the impacts of natural disasters on fertility outcomes, their implications for fertility preferences as a mechanism remain unexplored. This study proposes that natural disasters could promote fertility preferences by reinforcing traditional values. The empirical analysis relies on a post-tsunami longitudinal survey of individuals in the provinces of Aceh and North Sumatra in Indonesia frankenberg2020study. Out of the 28,376 survey respondents, our sample considers around 10,700 individuals aged 15 or more, whose responses are available for the variables used in the estimation. The results from individual-level cross-sectional regressions suggest that the ideal number of children increased with the extent of tsunami damage in that region. The increased fertility preference was more pronounced for people with greater religiosity and those who strengthened their family ties after the tsunami, supporting that the shift in fertility preference was intertwined with the rise of traditional values. For policymakers, our findings raise the need to consider the potentially lasting implications of shifts in cultural attitudes toward fertility beyond immediate post-disaster relief efforts. To address the limitations of our cross-sectional evidence, future research will need to investigate the dynamic relationship between fertility preferences and natural disasters using alternative data. [ABSTRACT FROM AUTHOR]

This document discusses the need for comprehensive assessments of multi-hazard risks in urban areas to enhance resilience and sustainability. It highlights the complex matrix of urban risk, including various elements at risk and multiple types of hazards. The document also emphasizes the importance of understanding the interactions among these factors and the need for people-centered risk management strategies. The document includes a collection of research articles that provide insights into various aspects of multi-hazard risk assessment and mitigation in urban environments, showcasing diverse methodologies and perspectives from researchers across the globe. [Extracted from the article]

Tailings dam breaches (TDBs) and subsequent flows can pose significant risk to public safety, the environment, and the economy. Numerical runout models are used to simulate potential tailings flows and understand their downstream impacts. Due to the complex nature of the breach-runout processes, the mobility and downstream impacts of these types of failures are highly uncertain. We applied the first-order second-moment (FOSM) methodology to a database of 11 back-analyzed historical tailings flows to evaluate uncertainties in TDB runout modelling and conducted a sensitivity analysis to identify key factors contributing to the variability of the HEC-RAS model output, including at different locations along the runout path. The results indicate that prioritizing resources toward advancements in estimating the values of primary contributors to the sensitivity of the selected model outputs is necessary for more reliable model results. We found that the total released volume is among the top contributors to the sensitivity of modelled inundation area and maximum flow depth, while surface roughness is among the top contributors to the sensitivity of modelled maximum flow velocity and flow front arrival time. However, the primary contributors to the sensitivity of the model outputs varied depending on the case study; therefore, the selection of appropriate rheological models and consideration of site-specific conditions are crucial for accurate predictions. The study proposes and demonstrates the FOSM methodology as an approximate probabilistic approach to model-based tailings flow runout prediction, which can help improve the accuracy of risk assessments and emergency response plans. [ABSTRACT FROM AUTHOR]

The widespread use of rubble-mound (RM) breakwaters along coasts across the world highlights the importance of understanding their behavior during natural disasters such as tsunamis. The failure of these breakwaters during tsunamis can have far-reaching consequences, potentially causing damage to coastal infrastructure and loss of life. Many breakwaters failed during past tsunamis. Despite this, studies on the behavior of RM breakwaters during tsunamis are minimal. The present study thus attempts to elucidate the behavior of RM breakwater subjected to a tsunami. Furthermore, efforts were made to develop effective countermeasures that can safeguard the breakwater against tsunamis. To the end, a novel technique of using geogrids for reinforcing the RM is proposed. This study could be a pioneering application of geogrids as reinforcing elements in RM breakwaters to mitigate damages from tsunamis. Geogrid layers are provided on both the seaside and harborside to mitigate tsunami-induced damage to the breakwater. In addition, a crown wall (with shear keys) is also introduced to prevent the scouring of the crest and sheet piles from preventing excess seepage through the seabed. Physical model tests, analytical studies and numerical simulations were carried out to assess the performance of the proposed countermeasures by comparing it with the behavior of conventional RM breakwater during the tsunami. The tsunamis can overflow the breakwater, potentially exceeding its design limits. Hence, provision was made in the study for overflow, where the breakwater may overflow by the tsunami. It was observed that excess seepage through the body of the breakwater and the scouring of the crest were significant factors that led to the failure of RM breakwaters under tsunami overflow. A novel reinforced model was proposed to address these issues. This model effectively withstood tsunami-induced damages without significant deformations, demonstrating its potential as a reliable solution. In the past, tsunamis have caused significant damage to several rubble-mound breakwaters, leading to devastating impacts on coastal communities. The 2004 Indian Ocean tsunami and the 2011 Great East Japan tsunami are two well-known examples of the destructive power of tsunamis. A significant number of breakwaters across the globe are of the rubble-mound type, and finding a practical solution to make them resilient against tsunamis could protect many coasts against future tsunamis. This study proposes novel reinforcing techniques to make the rubble-mound breakwater tsunami-resilient. These techniques include adding geogrid layers on either side, providing a crown wall (with shear key) at the top, and inserting two sheet piles into the seabed at either end of the rubble-mound breakwater. Perhaps, this is the first-time geogrids were used on rubble-mound breakwaters to mitigate tsunami-induced damages. The reinforcing elements were chosen for their practicality in the real world. These elements can be practically applied to make existing and future breakwaters tsunami resilient. The study found that the proposed reinforced model, particularly Reinforced model III, remained intact without significant deformation even under a 15-m high tsunami. [ABSTRACT FROM AUTHOR]

Several rubble mound breakwaters (RMB) were damaged and even collapsed during the past tsunamis. The main reasons for the failure of the breakwaters occurred due to the combined effects of seepage and scouring. Limited articles are available dealing with the behaviour of RMB during the tsunami. Furthermore, few available articles are related to developing countermeasures for the RMB against tsunamis. Therefore, an attempt has been made in the study to determine the exact behaviour of the RMB under the action of the tsunami. In addition, the main aim of the present study is to develop countermeasures to make the breakwater tsunami resilient. The present study proposes a novel geosynthetics-reinforced RMB to mitigate tsunami-induced breakwater damage. Based on the available information, this is the first time geosynthetics have been used in the RMB to mitigate tsunami-induced damage. Geogrid layers, geobags, sheet piles and crown walls (with shear keys) are adopted as countermeasure elements against the tsunami. Since the height of a tsunami can exceed its design tsunami height, tsunami waves were allowed to overflow the breakwater in physical model tests. Comparative analyses between the reinforced and unreinforced RMB were performed by conducting physical model tests, analytical tools, and numerical simulations. • Past tsunamis have caused damage and even collapse of rubble mound breakwaters. • A novel reinforcing technique is proposed to make tsunami resilient breakwater. • Reinforcements include geosynthetics, sheet piles and crown wall with shearkey. • Geosynthetic reinforced breakwater remained undamaged during the tsunami. [ABSTRACT FROM AUTHOR]

The 2004 Aceh tsunami tragedy was one of the most catastrophic occurrences, resulting in damage and severe casualties in multiple countries. This study proposes a hybrid coastal protection system made up of mangroves, a sea dike, a trench, or a combination of the three structures to prevent similar devastation in the future. This system is expected to reduce the tsunami wave height, thus lowering their potential damage. The tsunami wave propagation is reproduced using a nonlinear shallow water equation model. To construct a numerical scheme, a staggered grid finite volume method is implemented. This scheme is then validated using several benchmark tests. Once validated, the computational results are compared to experimental data collected at the Laboratory of Coastal Dynamics in Yogyakarta, Indonesia. Both the physical and numerical models use the downscaled Aceh tsunami waves and real bathymetry. Several scenarios of structures combination are presented with the aim to determine the most effective combination. A sensitivity analysis is also conducted to support the results. [ABSTRACT FROM AUTHOR]

This paper studies the damage spectra of single-degree-of-freedom (SDOF) systems for tsunami loading. The 2011 Tohoku tsunami wave traces are computed and obtained by adopting the Cornell Multi-grid Coupled Tsunami (COMCOT) model and are further verified by the Tohoku Tsunami Joint Survey (TTJS) data. The tsunami response analyses of SDOF systems are conducted taking into account the dynamic analysis method. The classical ductility damage is considered as the damage performance. The damage spectra are computed for five force reduction factors and 791 tsunami loadings. The effects of inundation depths, hysteretic model, post-yield stiffness ratio, α , viscous damping ratio, ξ , are explored and interpreted scientifically and statistically. The results demonstrate that the effect of the hysteretic model, force reduction factor, R, post-yield stiffness ratio, α , viscous damping ratio, ξ , on the damage of the structure is evident. Comparison with the static method and influence analysis of structural damping indicate the necessity for the application of the dynamic method. A simplified predictive formulation is developed for the evaluation of structural damage for tsunami loadings. [ABSTRACT FROM AUTHOR]

The alarming increase in extreme weather events, such as severe storms with torrential rain and strong winds, is a direct result of climate change. These events have led to discernible shifts in forest structure and the carbon cycle, primarily driven by a surge in tree mortality. However, the impacts caused by these severe storms on the production and carbon increment from coarse woody debris (CWD) are still poorly understood, especially in the Brazilian Atlantic Forest. Thus, the goal proposed by the study was to quantify the CWD volume, necromass, and carbon stock before and after the occurrence of a severe storm and to determine the importance of spatial, structural, and qualitative variables of trees in the CWD carbon increment. The increase in carbon by the storm was 2.01 MgC ha−1, with a higher concentration in the CWD less decomposed and smaller diameter class. The forest fragment plots showed distinct increments (0.05–0.35 MgC), being influenced by spatial (elevation, declivity, and slope angle) structural (basal area) and qualitative factors (trunk quality and tree health), intrinsic to the forest. Thus, it is concluded that severe storms cause a large increase in carbon in CWD, making it essential to understand the susceptibility of forests to the action of intense rains and strong winds to model and monitor the future impacts of these extreme weather events on Atlantic Forest and other tropical forests in the world. [ABSTRACT FROM AUTHOR]

This study was conducted to elaborate on the factors contributing to indirect deaths due to earthquakes between 1995 and 2016 in Japan and to identify their prevalence by focusing on life and health changes. A content analysis was conducted to determine the factors using documents provided by the local government. From the 472 indirect death cases, 12 categories and 137 detailed factors were identified. From the 13 cases related to suicide, six categories and 15 detailed factors were extracted. Among the categories, intense disaster-related work was ranked highest, followed by damage to jobs and property and family changes. For the other 459 non-suicide related causes of death, 12 categories and 122 detailed factors were extracted. The most prevalent categories were related to delay or interruption of treatment due to hospital shutdowns, followed by changes in living conditions. In detailed factor of living conditions, cold or hot environments—which are due to being washed away by tsunamis, weather, drafty shelters, the number of evacuees, damaged infrastructure, and a lack of clothes—were found in 60 cases. In conclusion, maintenance of medical services, promotion of a safe environment, and identification and intervention of high-risk people based on these factors are imperative. Developing assessment tools based on these factors for future research is essential to estimate the size of high-risk populations, assist in the distribution of limited resources, and respond quickly to survivors in disasters. [ABSTRACT FROM AUTHOR]

Predicting earthquakes through reasonable methods can significantly reduce the damage caused by secondary disasters such as tsunamis. Recently, machine learning (ML) approaches have been employed to predict laboratory earthquakes using stick-slip dynamics data obtained from sheared granular fault experiments. Here, we adopt the combined finite-discrete element method (FDEM) to simulate a two-dimensional sheared granular fault system, from which abundant fault dynamics data (i.e., displacement and velocity) during stick-slip cycles are collected at 2203 "sensor" points densely placed along and inside the gouge. We use the simulated data to train LightGBM (Light Gradient Boosting Machine) models and predict the gouge-plate friction coefficient (an indicator of stick-slips and the friction state of the fault). To optimize the data, we build the importance ranking of input features and select those with top feature importance for prediction. We then use the optimized data and their statistics for training and finally reach a LightGBM model with an acceptable prediction accuracy (R2 = 0.94). The SHAP (SHapley Additive exPlanations) values of input features are also calculated to quantify their contributions to the prediction. We show that when sufficient fault dynamics data are available, LightGBM, together with the SHAP value approach, is capable of accurately predicting the friction state of laboratory faults and can also help pinpoint the most critical input features for laboratory earthquake prediction. This work may shed light on natural earthquake prediction and open new possibilities to explore useful earthquake precursors using artificial intelligence. [ABSTRACT FROM AUTHOR]

Non‐inertial afterslip has been inferred to occur following large earthquakes. An explanation for this slow slip phenomenon is that coseismically generated stresses induce sliding on parts of a fault surface with velocity‐strengthening frictional properties. Here we develop an alternative mesoscale heuristic explanation for afterslip based on the idea that afterslip may occur on any portion of a fault that exhibits positive residual geometric moment following an earthquake, including sections that ruptured coseismically. Following a large earthquake, this model exhibits exponential time decay of afterslip and allows for variable sensitivity to coseismic event magnitude and residual geometric moment. This model provides a partial explanation for the spatial relationship of co‐ and post‐seismic slip associated with the 2011 MW = 9 Tohoku‐oki earthquake. Plain Language Summary: Afterslip is slow slip that occurs after large earthquakes. Some geodetic inferences of afterslip suggest that regions experiencing afterslip may have also slipped coeismically. This spatially coincident behavior is poorly explained by classical stress‐driven afterslip models. Here, we develop a motion‐based model to explain this possible spatial relationship. The model predicts faster afterslip rates in regions that have an excess of accumulated slip to be released following a large earthquake. This model may be used to describe the spatial relationship of co‐ and post‐seismic slip associated with the 2011 Great Japan earthquake. Key Points: We develop a geometric moment based model for time‐dependent afterslipThe model exhibits and exponential time decay of afterslip ratesThis model provides a kinematic explanation for overlapping co‐ and post‐seismic slip proximal to the 2011 great Japan earthquake [ABSTRACT FROM AUTHOR]

The structural styles and magnitudes of Alpine tectonic inversion are reviewed for the Atlantic margin of southwestern (SW) Iberia, a region known for its historical earthquakes, tsunamis and associated geohazards. Reprocessed, high-quality 2D seismic data provide new images of tectonic faults, which were mapped to a depth exceeding 10 km for the first time. A total of 26 of these faults comprise syn-rift structures accommodating vertical uplift and horizontal advection (shortening) during Alpine tectonics. At the regional scale, tectonic reactivation has been marked by (a) the exhumation of parts of the present-day continental shelf, (b) local folding and thrusting of strata at the foot of the continental slope, and (c) oversteepening of syn- and post-rift sequences near reactivated faults (e.g. "passive uplift"). This work proves, for the first time, that geometric coherence dominated the growth and linkage of the 26 offshore faults mapped in SW Iberia; therefore, they are prone to reactivate as a kinematically coherent fault network. They form 100–250 km long structures, the longest of which may generate earthquakes with a momentum magnitude (Mw) of 8.0. Tectonic inversion started in the Late Cretaceous, and its magnitude is greater close to where magmatic intrusions are identified. In contrast to previous models, this work postulates that regions in which Late Mesozoic magmatism was more intense comprise thickened, harder crust and form lateral buttresses to northwest–southeast compression. It shows these structural buttresses to have promoted the development of early stage fold-and-thrust belts – typical of convergent margins – in two distinct sectors. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) fully-coupled fluid-structure model has been developed in this study to calculate the impact force of tsunamis on a flexible structure considering fluid-structure interactions. The propagation of a tsunami is simulated by solving the 3D Navier–Stokes equations using a finite volume method with the volume-of-fluid technique. The structure motion under the tsunami impact force is simulated by solving the motion equation using the generalized alpha method. The structure motion is fed back into the fluid solver via a technique that combines a sharp-interface immersed boundary method with the cut-cell method. The flow model predicts accurate impact forces of dam-break flows on rigid blocks in three experimental cases. The fully coupled 3D flow-structure model is tested with experiments on a large-scale (1:5) model bridge under nonbreaking and breaking solitary waves. The simulated wave propagation and structure restoring forces generally agree well with the measured data. Then, the fully-coupled fluid-structure model is compared with an uncoupled model and applied to assess the effect of flexibility on structure responses to tsunami loading, showing that the restoring force highly depends on the dynamic characteristics of the structure and the feedback coupling between fluid and structure. The maximum hydrodynamic and restoring forces decrease with increasing structure flexibility. [ABSTRACT FROM AUTHOR]

The accident at the Fukushima NPP has revealed a certain drawback of traditional methods of registration of ionizing radiation by means of the automated radiation monitoring system, because in the conditions of the accident at the NPP the monitoring posts of the system were damaged as a result of the tsunami (23 of 24), which did not allow to evaluate the degree of radioactive contamination of the area in the early stages. In such conditions the most promising method of radiation control carried out on the potentially hazardous area is a non-contact method using an unmanned dosimetry complex (UDC), the application of which would reduce the risk of exposure to additional dose loads of personnel carrying out search and reconnaissance work and, additionally, provide management not only with information regarding radioactive contamination of the environment, but also directly provide the results of the search and reconnaissance. However, apart from the equipment used to determine the radiation background (detectors, spectrometers, radiometers, etc.) an important part of the UDC is the organization of the dosimetry complex and the way of information transfer. A possible variant of data transmission channel from the dosimetry complex installed on the UDC to the operator's personal computer is presented using NRF radio modules as an example. [ABSTRACT FROM AUTHOR]

In this study, a real-time tsunami estimation method was developed using the linear superposition of Green's functions, which account for nonlinear tsunami effects around coastal areas. To this end, first, the nonlinear effects associated with the inundation and bottom friction and advection terms in a nonlinear long-wave model were investigated, focusing on large tsunamis around Urado Bay in Kochi Prefecture, Japan, which is at risk of future damage from tsunamis produced by the Nankai Trough earthquake. The results indicate that the effects of advection play a more significant role than those of the inundation and bottom friction in terms of accurately estimating near-shore tsunami propagation. Then, based on these results, Green's functions were modified to account for the linearly approximated effects of the advection terms. By applying the developed method to tsunamis around Urado Bay, it was demonstrated that accurate estimations of the water surface level and flow velocity changes could be quickly obtained at any location around the bay. The developed method can be applied to real-time tsunami inundation forecasting and off-shore evacuation simulations of vessels to support optimal evacuation decisions. [ABSTRACT FROM AUTHOR]

In tsunami inundations or slope disasters of heavy rain, a lot of floating debris or driftwood logs are included in the flows. The damage to structures from solid body impacts is more severe than the damage from the water pressure. In order to study free-surface flows that include floating debris, developing a high-accurate simulation code of free-surface flows with high performance for large-scale computations is desired. We propose the single-phase free-surface flow model based on the cumulant lattice Boltzmann method coupled with a particle-based rigid body simulation. The discrete element method calculates the contact interaction between solids. An octree-based AMR (Adaptive Mesh Refinement) method is introduced to improve computational accuracy and time-to-solution. High-resolution grids are assigned near the free surfaces and solid boundaries. We conducted two kinds of tsunami flow experiments in the 15 and 70m water tanks at Hachinohe Institute of Technology and Kobe University to validate the accuracy of the proposed model. The simulation results have shown good agreement with the experiments for the drifting speed, the number of trapped wood pieces, and the stacked angles. [ABSTRACT FROM AUTHOR]

Here we update a catalogue of 2001–2011 New Zealand earthquakes relocated with a 3-D seismic velocity model, which has recent improvements. We use P- and S-wave arrival times from earthquakes during 2001–2011 as these were manually picked with assigned quality. We demonstrate the usefulness of the catalogue by considering results from the southern South Island where GeoNet seismograph spacing is large. Later phase data used automatic picking and processing of arrival times. We relocate the 2019–2020 data from National Geohazards Monitoring Centre (NGMC) and compare seismicity patterns to consider its usefulness. We find that the auto-detected crustal earthquakes are more sparse in most of the southern South Island compared to the earlier analyst-picked data period, including Fiordland, which is one of the most seismically active areas in New Zealand. The auto-detected seismicity pattern is also problematic at greater depth and does not show a seismicity band in the lower crust across Southland evident in 2001–2011 data. The detection capability could be improved with a much denser permanent network. We recommend that the 2001–2011 relocated catalogues be used in studies of tectonics and seismic hazard across the South Island, and in studies that consider New Zealand wide seismicity patterns. [ABSTRACT FROM AUTHOR]

Cilacap is one of several areas that experienced significant damage due to the Pangandaran tsunami in 2007. Currently, tsunamis are one of the most serious threats to coastal areas as they can cause devastation to the function of coastal areas. The physical environment can extensively affect the probability of damage caused by tsunamis. In addition, it is critical to maintain building stability as a substantial component in the integrated management efforts of coastal areas. The aim of this research is to assess the physical susceptibility and the vulnerability of school buildings to tsunami, particularly senior high school buildings (known as SMA/MA) located in the coastal area of the Cilacap region. This research is essential for the continuity of learning and teaching activities in the coastal area. Therefore, mapping the physical environment and school buildings in the coastal area of the Cilacap region is necessary. In this study, the physical approach method and Papathoma Vulnerability Tsunami Assessment (PVTA) model were optimally applied to assess coastal vulnerabilities to tsunami. Ultimately, the results were further evaluated by using cross-tabulation. The results confirm that specific coastal areas were categorised as having "moderate to high" susceptibility. Simultaneously, owing to the field survey, we determined that school buildings at this location were made of simple reinforced concrete materials. Notwithstanding that the vulnerability of the school buildings were low, the conditions were deemed to be reasonably harmful given that the schools were located in a "moderate to high" susceptibility. The results of this study have implications for the level of potential physical susceptibility of the coastal areas and the vulnerability of school buildings to tsunamis in the Cilacap region. [ABSTRACT FROM AUTHOR]

The city of Banda Aceh continues to grow and develop to this day after being hit by the tsunami disaster in 2004. The growth and development of Banda Aceh did not happen simultaneously. It can be seen in Meuraxa District, Jaya Baru District, and other districts affected by the Tsunami. As a result, the growth centers shifted in Banda Aceh City. The high level of development until 2021, using the GRDP of Banda Aceh City, which is 19.93 trillion rupiah, means that economic growth will also increase by 1.25 percent from 2003 before the Tsunami to 2021, thereby creating economic potential in Banda Aceh City. The developing economic interaction between sub-districts in Banda Aceh City will create the strongest interaction as a new growth center on the basis of data from before and after the Tsunami, namely the number of population increases and the absolute distance between the two regions. The gravity analysis model identifies interactions between sub-districts in Banda Aceh City. It means they have strong economic interactions as growth centers by gaining the strength of interaction between two regions in Banda Aceh City. The gravity analysis model produces interaction areas with the strongest interaction values in 2004 (before Tsunami), 2005 (after the Tsunami), and 2021 (currently), which are the interactions between Kuta Alam and Baiturrahman Districts with interaction values for each year of 283,084,961,591; 161,382,469,959 and 190,617,812,346. [ABSTRACT FROM AUTHOR]

Natural hazards like floods, cyclones, earthquakes, or, tsunamis have deep impacts on the environment and society causing damage to both life and property. These events can cause widespread destruction and can lead to long-term socio-economic disruption often affecting the most vulnerable populations in society. Computational modeling provides an essential tool to estimate the damage by incorporating spatial uncertainties and examining global risk assessments. Classical stationary models in spatial statistics often assume isotropy and stationarity. It causes inappropriate smoothing over features having boundaries, holes, or physical barriers. Despite this, nonstationary models like barrier model have been little explored in the context of natural disasters in complex land structures. The principal objective of the current study is to evaluate the influence of barrier models compared to classical stationary models by analysing the incidence of natural disasters in complex spatial regions like islands and coastal areas. In the current study, we have used tsunami records from the island nation of Maldives. For seven atoll groups considered in our study, we have implemented three distinct categories of stochastic partial differential equation meshes, two for stationary models and one that corresponds to the barrier model concept. The results show that when assessing the spatial variance of tsunami incidence at the atoll scale, the barrier model outperforms the other two models while maintaining the same computational cost as the stationary models. In the broader picture, this research work contributes to the relatively new field of nonstationary barrier models and intends to establish a robust modeling framework to explore spatial phenomena, particularly natural hazards, in complex spatial regions having physical barriers. [ABSTRACT FROM AUTHOR]

Floods pose significant risk to riparian buildings as evidenced during many historical events. Although structural resilience to tsunami flooding is well studied in the literature, high-velocity and debris-laden floods in steep terrains are not considered adequately so far. Historical floods in steep terrains necessitate the need for flood vulnerability analysis of buildings. To this end, we report vulnerability of riparian-reinforced concrete buildings using forensic damage interpretations and empirical/analytical vulnerability analyses. Furthermore, we propose the concept and implications of functionality loss due to flooding in residential reinforced concrete (RC) buildings using empirical data. Fragility functions using inundation depth and momentum flux are presented for RC buildings considering a recent flooding event in Nepal. The results show that flow velocity and sediment load, rather than hydrostatic load, govern the damages in riparian RC buildings. However, at larger inundation depth, hydrostatic force alone may collapse some of the RC buildings. [ABSTRACT FROM AUTHOR]

Despite significant research on the effects of stress on the hypothalamic-pituitary-adrenal (HPA) axis, questions remain regarding long-term impacts of large-scale stressors. Leveraging data on exposure to an unanticipated major natural disaster, the 2004 Indian Ocean tsunami, we provide causal evidence of its imprint on hair cortisol levels fourteen years later. Data are drawn from the Study of the Tsunami Aftermath and Recovery, a population-representative longitudinal study of tsunami survivors who were living along the coast of Aceh, Indonesia, when the tsunami hit. Annual rounds of data, collected before, the year after and 2 y after the disaster provide detailed information about tsunami exposures and self-reported symptoms of post-traumatic stress. Hair samples collected 14 y after the tsunami from a sample of adult participants provide measures of cortisol levels, integrated over several months. Hair cortisol concentrations are substantially and significantly lower among females who were living, at the time of the tsunami, in communities directly damaged by the tsunami, in comparison with similar females living in other, nearby communities. Differences among males are small and not significant. Cortisol concentrations are lowest among those females living in damaged communities who reported elevated post-traumatic stress symptoms persistently for two years after the tsunami, indicating that the negative effects of exposure were largest for them. Low cortisol is also associated with contemporaneous reports of poor self-rated general and psychosocial health. Taken together, the evidence points to dysregulation in the HPA axis and "burnout" among these females fourteen years after exposure to the disaster. [ABSTRACT FROM AUTHOR]

Coastal dikes are an essential social infrastructure to mitigate tsunami damage. However, there are no clear guidelines on effective dike shapes for reducing tsunami overflow. To examine effective dike shapes, numerical simulations of the amount of tsunami overflow at coastal dikes are conducted with reference to tsunami waveforms caused by the Great East Japan Earthquake. Results reveal the relationship between the dike shape and the amount of the overflow; the mechanism of overflow reduction based on the velocity and water level distribution is also verified. The comparison of the seaward and landward slopes of coastal dikes reveals that the seaward slope has a greater impact on the overflow, and the seaward slope with a vertical wall or a wave return structure reduces the overflow by 5%–30% compared to the 1:2 (26.6°) seaward slope. The landward slope should be determined based on the tsunami scale and the scour related to the dike stability. Since tsunami inflow damages human life and social infrastructure, achieving the overflow reduction without increasing dike height is vital. Our work contributes to rational design guidelines for coastal dikes. [ABSTRACT FROM AUTHOR]

The "blue economy" idea promotes the responsible and sustainable use of coastal and marine resources. The need to balance the exploitation and economic use of these resources has moved to the top of the research agenda and management priorities for small island developing states (SIDS). SIDS face unique challenges due to their geographic, economic, and environmental characteristics. While the specific challenges can vary based on the individual SIDS, some common future challenges include (i) climate change and sea-level rise resulting from the increased frequency and intensity of storms and coastal erosion; (ii) natural disasters such as hurricanes, cyclones, tsunamis, and earthquakes, resulting in extensive damage, disruption of essential services, and lead to loss of lives and livelihoods; (iii) lack of sustainable development and economic diversification leading to reliance on few key sectors, such as tourism and agriculture, which are vulnerable to market fluctuations; (iv) energy security and renewable energy transition; as there is dependency on imported fossil fuels for their energy needs, price fluctuations and supply disruptions occurs; (v) biodiversity conservation and marine resource management; they host unique ecosystems and rich biodiversity, including coral reefs, mangroves, and marine species; and (vi) access to finance and technology; there are direct opportunities, for accessing funds to support technology development under sustainable finance projects. This themed article set attracted 14 submissions, 7 of which were accepted for publication. The topics covered fisheries, climate change effects, marine litter, and development of new technologies and finance mechanisms to support the SIDS. Overall, these contributions have emphasized the remarkable role that SIDS play in the protection and management of coastal and marine ecosystems, but also highlighted several needs and key priorities. [ABSTRACT FROM AUTHOR]

Historical records with recent events reveal that tsunamis are threatening the western coast of Turkey due to the intensely active seismicity of the Eastern Mediterranean Sea. The most recent tsunami events in the region (30 October 2020 Izmir-Samos and 20 July 2017 Bodrum-Kos) restated that the cities located near the Eastern Mediterranean and connected seas should also consider tsunami events in their disaster mitigation plans. Bodrum is one of the most critical coastal districts vulnerable to marine hazards, with popular hotels, numerous coastal facilities, long and famous beaches, cultural, historical and touristic places. Tsunami evacuation planning is required for Bodrum district to mitigate the damage caused by destructive tsunami waves inundating on land. This study calculates the geospatial distribution of pedestrian evacuation time, based on selected credible worst-case scenarios. A widely used anisotropic least-cost distance model is applied via the Pedestrian Evacuation Analyst Tool to calculate the required time for a pedestrian to evacuate the region under tsunami threat based on the selected scenarios. The model includes landscape properties that affect the walking pace of pedestrians during an evacuation, such as elevation, slope, land cover, and land use types (beach, road, bushes, water bodies, and barriers). The resultant pedestrian evacuation time maps show that the maximum time needed for a pedestrian is 8, 6, 5, 4, and 3 min for highly populated coastal settlements of Bodrum, which are Central Bodrum, Yahsi, Akyarlar-Karaincir-Aspat Bays, Bitez, and Gumbet Bays, respectively. [ABSTRACT FROM AUTHOR]

Despite the importance of critical infrastructure for the effective functioning of communities, their vulnerability to tsunamis remains unstudied. This study addresses this issue by developing empirical fragility curves for infrastructure components currently absent from tsunami vulnerability research. This research applies post-event damage data from the 2015 Illapel tsunami in a cumulative link model (CLM) to form fragility curves for three-waters (manholes, culverts, and drain inlets) and railway infrastructure components. The synthesized fragility curves reveal that in response to the flow depth, culverts exhibit the highest vulnerability of all the infrastructures studied. The curves also suggest that culverts, drain inlets, and railways have higher vulnerability when compared to infrastructure such as roads or utility poles. [ABSTRACT FROM AUTHOR]

Reliable forecasts of building damage due to debris flows may provide situational awareness and guide land and emergency management decisions. Application of debris-flow runout models to generate such forecasts requires combining hazard intensity predictions with fragility functions that link hazard intensity with building damage. In this study, we evaluated the performance of building damage forecasts for the 9 January 2018 Montecito postfire debris-flow runout event, in which over 500 buildings were damaged. We constructed forecasts using either peak debris-flow depth or volume flux as the hazard intensity measure and applied each approach using three debris-flow runout models (RAMMS, FLO-2D, and D-Claw). Generated forecasts were based on combining multiple simulations that sampled a range of debris-flow volume and mobility, reflecting typical sources and magnitude of pre-event uncertainty. We found that only forecasts made with volume flux and the D-Claw model could correctly forecast the observed number of damaged buildings and the spatial patterns of building damage. However, the best forecast only predicted 50% of the observed damaged buildings correctly and had coherent spatial patterns of incorrectly forecast building damage (i.e., false positives and false negatives). These results indicate that forecasts made at the building level reliably reflect the spatial pattern of damage, but do not support interpretation at the individual building level. We found the event size strongly influences the number of damaged buildings and the spatial pattern of debrisflow depth and velocity. Consequently, future research on the link between precipitation and the volume of sediment mobilized may have the greatest effect on reducing uncertainty in building damage forecasts. Finally, because we found that both depth and velocity are needed to forecast building damage, comparing debris flow models against spatially distributed observations of building damage is a more stringent test for model fidelity than comparison against the extent of debris-flow runout. [ABSTRACT FROM AUTHOR]

Some areas of the California coast have physical conditions—such as local bathymetry, topography, shoreline orientation, and other factors—that increase the risk for damage from tsunami inundation compared with other regions. Technical tsunami hazard analyses can inform decision-makers on regional planning and policy decisions. In this paper, we focus on recent efforts in California to delineate various tsunami hazard zones along the coastline under the Seismic Hazard Mapping Act, wherein structural mitigation measures will be recommended. To define the zone wherein structural mitigation measures are recommended, we present a state-wide tsunami reliability analysis that combines existing probabilistic hazard information and structure fragility curves derived from recent events. We examine design-life chances of significant structural damage for various structure types along all developed coastlines throughout California and use this analysis to show how hazard and risk have different correlations throughout the State. Finally, we outline an approach for creating mitigation zones, which provides state-wide tsunami risk consistency for all structures in the tsunami inundation zone. [ABSTRACT FROM AUTHOR]

Vehicles are one of the most common objects that are usually washed away by the water flow during flood events resulting in several damages and casualties. Regardless of the vehicle type and flow condition, vehicle orientations in relation to the incoming flow play a significant role on the vehicles stability limits. Therefore, studying the hydrodynamic forces on a vehicle placed at different angles with respect to the incoming flow can help to understand the most unstable orientation. As a result, parking lots design may improve by rearranging the vehicles in a way that the critical vehicle orientation will not face the expected incoming flow. Herein, 3-dimensional numerical modelling was conducted to assess the critical orientation of a parked full-scale passenger vehicle exposed to water flow at three different angles, namely 0°, 45°, and 90°. The highest drag force and displacement were observed for the vehicle at 90° orientation making it the critical one. While the highest torque on the vehicle centre of mass was reported for the vehicle at 45° orientation, making it more rotatable when compared with other orientations. Obtained results were compared with previously published experimental studies and good agreements were observed. [ABSTRACT FROM AUTHOR]

The urgent necessity to fortify coastal regions and safeguard both the natural environment and key coastal infrastructure underscores the significance of structural measures in coastal engineering. Among these, the seawall reigns as the primary fortification method. This study aims to elucidate the impact of a stepped structure on the propagation and overtopping of solitary waves when they encounter an impermeable seawall. The investigation has been conducted using ANSYS Fluent, a widely recognized commercial software. Although previous researchers have extensively used the two-dimensional volume of fluid (VOF) model, based on the Reynolds-Averaged Navier-Stokes (RANS) equations and the k-e turbulence closure solver, this study fills the gap in the understanding of the stepped structure's effect. It shows a commendable agreement with experimental results, proving its reliability. Simulations were executed with varied configurations of stepped structures (Step width Sw=0.6 m, 1.2 m, 1.8 m, and Step height Sh=0.3 m, 0.6 m, 0.9 m), emulating tsunami waves of constant wave height and water depth over a stepped structure on a 1:20 sloped beach. Initially, the accuracy of the results was substantiated by comparing them with experimental and numerical data of the free surface and the distribution of the pressure field on the seawall. Numerical simulations, incorporating varying wave heights, water depths, and step heights, were performed to scrutinize the evolution of waves and the pressure exerted by waves impacting the seawall. [ABSTRACT FROM AUTHOR]

In recent years, large-scale heavy rainfall disasters have occurred frequently in several parts of the world. Therefore, a quantitative approach to understanding how buildings are damaged during floods is necessary to develop appropriate flood-resistant technologies. In flood inundation simulations for the quantitative evaluation of a building's resistance to flooding, a subgrid model is necessary to appropriately evaluate the resistance of buildings smaller than the grid size at a medium grid resolution. In this study, a new subgrid (SG) 3D inundation model is constructed to evaluate the fluid force acting on buildings and assess the damage to individual buildings during flood inundation. The proposed method does not increase the computational load. The model is incorporated into a 2D and 3D hybrid model with high computational efficiency to construct a 3D river and inundation flow model. Its validity and effectiveness are evaluated through comparisons with field observations and the conventional equivalent roughness model. Considering horizontal and vertical velocity distributions, the proposed model showed statistically significant improvements in performance in terms of building loss indices such as velocity and fluid force. These results suggest that the SG model can effectively evaluate the fluid force acting on buildings, including the vertical distribution of flow velocities. [ABSTRACT FROM AUTHOR]

This paper describes the numerical simulation of the solitary wave impact on a partially immersed and fixed structure located over a flat coastal slope. This topic is related to the need for assessment of the possible impact of long waves, such as tsunamis, on partially immersed structures in coastal waters. Numerical algorithms on a movable grid adapting to the motion of the shore point are developed for a fully nonlinear dispersive model and a dispersionless shallow water model. Their validation is carried out by comparing the obtained solutions with the data from laboratory experiments and with the results obtained using a fully nonlinear potential flow model. The study shows that the difference between the maximum wave impact on the body at the foot of the slope and near the shore can be up to 6 times. In many cases, the maximum horizontal component of the wave force occurs under the influence of the wave reflected from the shore, indicating the need to consider the influence of the shore-reflected wave when assessing the impact of long waves on structures located in coastal waters. Furthermore, the need to use runup algorithms instead of reflective boundary conditions (vertical wall) has been identified for gentler slopes, where the differences in the wave impact for these two configurations can be 2–3 times. [ABSTRACT FROM AUTHOR]

Tsunami occurs frequently all over the world in recent years, which has caused serious damage to coastal buildings and infrastructure. Therefore, it is of great significance to research on measures for onshore buildings against tsunamis. In this study, the multi-material ALE method is used to establish a numerical model for air-tsunami-structure interactions, and the influence of multistory building忆s penetration form and rate on tsunami impact load is investigated. The numerical results show that tsunami impact load is significantly affected by the penetration rate of a building when the tsunami is relatively weak, and the tsunami impact load decreases with the increase of the penetration rate. When a tsunami exceeds a certain strength, the effect of reduction of the tsunami impact loads on buildings becomes weaker with the increase of penetration rate when the perforation is uniformly arranged. However, the effect of reduction of tsunami impact loads on buildings will remain significant when the lower part of a building is completely open, and the tsunami impact load can be reduced to about 20% of that on impervious buildings. In addition, the results also show that the water runup when tsunami impacts a building decreases with the increase of the penetration rate, and the bow wave generated by reflection in front of the building is meanwhile weakened. [ABSTRACT FROM AUTHOR]

Assessing the destruction caused by a tsunami is a challenging task that must be completed quickly with limited resources and information. To address this issue, we propose a method for accurate damage mapping using binary classification of high-resolution satellite imagery, where we enhance the performance of three pre-trained deep neural network models (Vgg19, Inception, and Xception). The pre-trained models are used, which have been previously trained on large datasets, and transferred to our tsunami problem. We also develop a custom network architecture specifically designed for tsunami damage detection using high-resolution remote sensing data, improving the accuracy of automated binary classification. We investigate the impact of various parameters and learning rates to detect small objects, demonstrating the suitability of our approach for tsunami damage assessment. Our network outperforms traditional and current deep learning-based approaches, as it shows low bias and high variance datasets that result in a skillful model. Specifically, we observe that Inception-v3 performs best on the dataset, exhibiting good behavior with low errors and achieving the best overall score with 24.11 min, while other models score between 30.50 min for Vgg19 and 45.33 min for Xception. Our study focuses on two important binary classification categories, tsunami-stricken and non-stricken areas, for which we train the proposed framework on a dataset comprising 30,000 small tiles of high-resolution satellite images obtained from Mexer satellite images. The model is validated on 8000 images using the Jupyter notebook of the Anaconda deep learning framework. [ABSTRACT FROM AUTHOR]

Currently available performance-based methodologies for assessing the fragility of structures subjected to tsunami neglect the effects of tsunami-induced vertical loads due to internal buoyancy. This paper adopts a generalized methodology for the performance assessment of structures that integrates the effects of buoyancy loads on interior slabs during a tsunami inundation. The methodology is applied in the fragility assessment of three case-study frames (low, mid and high-rise), representative of existing masonry-infilled reinforced concrete (RC) buildings typical of Mediterranean region. The paper shows the effect of modelling buoyancy loads on damage evolution and fragility curves associated with different structural damage mechanisms for existing RC frames with breakaway infill walls including consideration of blow-out slabs. The outcomes attest that buoyancy loads affect the damage assessment of buildings during a tsunami, especially in the case of mid and high-rise structures with blow-out slabs. The rate of occurrence of slabs uplift failure increases with the number of stories of the building, indicating the need to account for such damage mechanism when assessing the performance of structures. It is also found that buoyancy loads slightly affect the fragility curves associated to other structural damage mechanisms for existing RC buildings commonly monitored for fragility assessment. [ABSTRACT FROM AUTHOR]

The increase in the magnitude of natural disasters has led to the development of risk assessment methodologies to indicate risk levels in qualitative terms. Among these, the Source-Pathway-Receptor-Consequence (SPRC) methodology assesses the risk from the source of the hazard to the possible consequences. In the present work, an economic evaluation was carried out on the substantial damages directly associated with the floods generated by a 10 m high tsunami off the coast of Zihuatanejo, Mexico. This event was identified as the worst-case scenario of tsunamis associated with a 8.4 Mw earthquake. The method followed was the SPRC, with an economic evaluation, applied to street level in Zihuatanejo. The economic costs were obtained from the results of this work using a criterion to characterize the percentage of damage to various types of housing and goods associated with different levels of flooding. This work is intended as a basis for the better planning of urban development, considering possible economic damage from tsunamis. It also provides a more objective perspective for distributing funds for mitigating natural disasters, allowing aid to be directed to the areas and types of housing with greatest risk from the flooding. [ABSTRACT FROM AUTHOR]