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The development of multi-hazard risk assessment frameworks has gained momentum in the recent past. Nevertheless, the common practice with openly available risk data sets, such as the ones derived from the United Nations Office for Disaster Risk Reduction Global Risk Model, has been to assess risk individually for each peril and afterwards aggregate, when possible, the results. Although this approach is sufficient for perils that do not have any interaction between them, for the cases where such interaction exists, and losses can be assumed to occur simultaneously, there may be underestimation of losses. The paper aims to discuss these issues.

This paper summarizes a methodology to integrate simultaneous losses caused by earthquakes and tsunamis, with a peril-agnostic approach that can be expanded to other hazards. The methodology is applied in two relevant locations in Latin America, Acapulco (Mexico) and Callao (Peru), considering in each case building by building exposure databases with portfolios of different characteristics, where the results obtained with the proposed approach are compared against those obtained after the direct aggregation of individual losses.

The fully probabilistic risk assessment framework used herein is the same of the global risk model but applied at a much higher resolution level of the hazard and exposure data sets, showing its scalability characteristics and the opportunities to refine certain inputs to move forward into decision-making activities related to disaster risk management and reduction.

This paper applies for the first time the proposed methodology in a high-resolution multi-hazard risk assessment for earthquake and tsunami in two major coastal cities in Latin America.

This paper aims to describe a multi-scenario assessment of the seismogenic tsunami hazard for Bangladesh from active subduction zones in the Indian Ocean region. Two segments of the Sunda arc, namely, Andaman and Arakan, appear to pose a tsunamigenic seismic threat to Bangladesh.

High-resolution numerical simulations of tsunami propagation toward the coast of Bangladesh have been carried out for eight plausible seismic scenarios in Andaman and Arakan subduction zones. The numerical results have been analyzed to obtain the spatial variation of the maximum tsunami amplitudes as well as tsunami arrival times for the entire coastline of Bangladesh.

The results suggest that the tsunami heights are amplified on either side of the axis of the submarine canyon which approaches the nearshore sea off Barisal in the seaboard off Sundarban–Barisal–Sandwip. Moreover, the computed tsunami amplitudes are comparatively higher north of the latitude 21.5o in the Teknaf–Chittagong coastline. The calculated arrival times indicate that the tsunami waves reach the western half of the Sundarban–Barisal–Sandwip coastline sooner, while shallow water off the eastern half results in a longer arrival time for that part of the coastline, in the event of an earthquake in the Andaman seismic zone. On the other hand, most parts of the Chittagong–Teknaf coastline would receive tsunami waves almost immediately after an earthquake in the northern segment of the Arakan seismic zone.

The present assessment includes probabilistic measures of the tsunami hazard by incorporating several probable seismic scenarios corresponding to recurrence intervals ranging from 25 years to over 1,000 years.

The purpose of this paper is to analyse the Fukushima nuclear disaster (FND) that occurred 11 March 2011 through the lens of the systemic and complexity theory. This analysis allows the proposition of some guidelines for the development of a more preventive and ethical approach in crisis management, including changes in human resource management and training.

Thanks to a layered analysis of the complex system that represents the FND and an actor/stake approach, this paper sheds light on the many failures that occurred on the personal, organizational, institutional, political and cultural level.

This analysis highlights that, beyond the apparent simplicity of the natural trigger events, a complex network of legal, cultural and technological paradigms, as well as the defense mechanisms of personal and organizational moral disengagement, have structured the context of this crisis, allowing for an event to turn into this disaster.

This study shows the limit of classical approach towards crisis management such as probabilistic risk assessment in terms of systemic and complexity: the assessment could be easily overcome if the mindset of the organization leaders is not already oriented towards preventive management.

The value of this study is participating to the effort of showing the need to develop more preventive mindsets and behaviours in the global economy, dealing with worldwide and complex issues.

This paper describes the phenomenon of tsunamis within the European Seas and explains how tsunami research has developed during the last 40 years as a response to a large tsunami which occurred in the Aegean Sea region of Greece in 1956. The paper states that specific tsunami hazard maps have been established for particular coastal areas of Greece and that these maps and any associated disaster management plans have been developed as a tool to mitigate the effects of future tsunamis in the region. The author provides the results of new investigations of the effects of a past tsunami in Greece and shows that the magnitude of this event has been overestimated. The results imply that revisions of the urban hazard maps and associated disaster preparedness plans should be considered.

Recent earthquake-induced liquefaction events and associated losses have increased researchers’ interest into liquefaction risk reduction interventions. To the best of the authors’ knowledge, there was no scholarly literature related to an economic appraisal of these risk reduction interventions. The purpose of this paper is to investigate the issues in applying cost–benefit analysis (CBA) principles to the evaluation of technical mitigations to reduce earthquake-induced liquefaction risk.

CBA has been substantially used for risk mitigation option appraisal for a number of hazard threats. Previous literature in the form of systematic reviews, individual research and case studies, together with liquefaction risk and loss modelling literature, was used to develop a theoretical model of CBA for earthquake-induced liquefaction mitigation interventions. The model was tested using a scenario in a two-day workshop.

Because liquefaction risk reduction techniques are relatively new, there is limited damage modelling and cost data available for use within CBAs. As such end users need to make significant assumptions when linking the results of technical investigations of damage to built-asset performance and probabilistic loss modelling resulting in many potential interventions being not cost-effective for low-impact disasters. This study questions whether a probabilistic approach should really be applied to localised rapid onset events like liquefaction, arguing that a deterministic approach for localised knowledge and context would be a better base for the cost-effectiveness mitigation interventions.

This paper makes an original contribution to literature through a critical review of CBA approaches applied to disaster mitigation interventions. Further, this paper identifies challenges and limitations of applying probabilistic based CBA models to localised rapid onset disaster events where human losses are minimal and historic data is sparse; challenging researchers to develop new deterministic based approaches that use localised knowledge and context to evaluate the cost-effectiveness of mitigation interventions.

Urban resilience is becoming increasingly important due to increasing degree of urbanization and a combination of several factors affecting urban vulnerability. Urban resilience is also understood as a capacity of a system to prepare, respond and recover from multi-hazard threats. The purpose of multi-risk approach (MRA) is to take into consideration interdependencies between multiple risks, which can trigger a chain of natural and manmade events with different spatial and temporal scales. The purpose of this study is to understand correlation between multi-risk approach and urban resilience.

To increase urban resilience, MRA should also include multi-risk governance, which is based on understanding how existing institutional and governance structures, individual judgments and communication of risk assessment results shape decision-making processes.

This paper is based on extensive fieldwork in the test studies of Naples, Italy and Guadeloupe, France, the historical case study analysis and the stakeholders’ interviews, workshops and focus groups discussions.

Multi-risk is a relatively new field in science, only partially developed in social and geosciences. The originality of this research is in establishment of a link between MRA, including both assessment and governance, and urban resilience. In this paper, the authors take a holistic and systemic look at the MRA, including all stages of knowledge generation and decision-making. Both, knowledge generation and decision-making are reinforced by behavioural biases, different perceptions and institutional factors. Further on, the authors develop recommendations on how an MRA can contribute to urban resilience.

Understanding risk is more than just modeling risk; it requires an understanding of the development and social processes that underlie and drive the generation of disaster risk. Here, in addition to a review of more technical factors, this paper aims to discuss a variety of institutional, social and political considerations that must be managed for the results of a risk assessment to influence actions that lead to reductions in natural hazard risk.

The technical approaches and the institutional, social and political considerations covered in this paper are based on a wide range of experiences gleaned from case studies that touch on a variety of activities related to assessing the risks and impacts of natural hazards, and from the activities of the World Bank’s Global Facility for Disaster Reduction and Recovery.

Risk information provides a critical foundation for managing disaster risk across a wide range of sectors. Appropriate communication of robust risk information at the right time can raise awareness and trigger action to reduce risk. Communicating this information in a way that triggers action requires an understanding of the developments and social processes that underlie and drive the generation of risk, as well as of the wider Disaster Risk Management (DRM) decision-making context.

Prior to the initiation of a quantitative risk assessment one should clearly define why an assessment is needed and wanted, the information gaps that currently prevent effective DRM actions and the end-users of the risk information. This requires developing trust through communication among the scientists and engineers performing the risk assessment and the decision-makers, authorities, communities and other intended users of the information developed through the assessment.

This paper summarizes the technical components of a risk assessment as well as the institutional, social and political considerations that should be considered to maximize the probability of successfully reducing the risk defined by a risk assessment.

Based on the existing provisions/operations of tsunami warning in the Indian Ocean, authors observed that detection as well as arrival time estimations of regional tsunami service providers (RTSPs) could be improved. In particular, the detection mechanisms have been eccentrically focussed on Sunda and Makran tsunamis, although tsunamis from Carlsberg ridge and Chagos archipelago could generate devastating tsunamis for which inadequate provisions exist for detection and arrival time/wave height estimation. RTSPs resort to assess estimated arrival time/wave heights from a scenario-based, pre-simulated database. These estimations in terms of Sri Lanka have been found inconsistent. In addition, current warning mechanism poorly manages non-seismic tsunamis. Thus, the purpose of this study is to investigate these drawbacks and attempt to carve out a series of suggestions to improve them.

The work initiated with data retrieved from global earthquake and tsunami databases, followed by an estimation of probabilities of tsunamis in the Indian Ocean with particular emphasis on Carlsberg and Chagos tsunamis. Second, probabilities of tsunami detection in each sub-region have been estimated with the use of available tide gauge and tsunami buoy data. Third, the difficulties in tsunami detection in the Indian Ocean are critically assessed with case studies, followed by recommendations to improve the detection and warning.

Probabilistic estimates show that given the occurrence of a significant earthquake, both Makran and Carlsberg/Chagos regions possess higher probabilities to harbour a tsunami than the Sunda subduction zone. Meanwhile, reliability figures of tsunami buoys have been declined from 79-92 to 68-91 per cent over the past eight years. In addition, a Chagos tsunami is left to be detected by only one tide gauge prior to it reaching Sri Lankan coasts.

The study uses an averaged tsunami speed of 882 km/h based on 2004 Asian tsunami. However, using exact bathymetric data, Tsunamis could be simulated to derive speeds and arrival times more accurately. Yet, such refinements do not change the main derivations and conclusions of this study.

Tsunami detection and warning in the Indian Ocean region have shown room for improvement, based on the inadequate detection levels for Carlesberg and Chagos tsunamis, and inconsistent warnings of regional tsunami service providers. The authors attempted to remedy these drawbacks by proposing a series of suggestions, including a deployment of a new tsunami buoy south of Maldives, revival of offline buoys, real-time tsunami simulations and a strategy to deal with landslide tsunamis, etc.

Indian Ocean is prone to mega tsunamis as witnessed in 2004. However, more than 50 per cent of people in the Indian Ocean rim countries dwell near the coast. This is verified with deaths of 227,898 people in 14 countries during the 2004 tsunami event. Thus, it is of paramount importance that sufficient detection levels are maintained throughout the Indian Ocean without being overly biased towards Sunda tsunamis. With respect to Sri Lanka, Makran, Carlesberg or Chagos tsunamis could directly hit the most populated west coast and bring about far worse repercussions than a Sunda tsunami.

This is the first instance where the threats from Carlesberg and Chagos tsunamis to Sri Lanka are discussed, probabilities of tsunamis are quantified and their detection levels assessed. In addition, reliability levels of tsunami buoys and tide gauges in the Indian Ocean are recomputed after eight years to discover that there is a drop in reliability of the buoy data. The work also proposes a unique approach to handle inconsistencies in the bulletins of regional tsunami service providers, and to uphold and improve dwindling interest on tsunami buoys.

The purpose of this paper is to present an assessment of the potential tsunamigenic seismic hazard to Sri Lanka from all active subduction zones in the Indian Ocean Basin.

The assessment was based on previous studies as well as past seismicity of the subducion zones concerned.

Accordingly, four seismic zones capable of generating teletsunamis that could reach Sri Lanka have been identified, namely, Northern Andaman‐Myanmar, Northern Sumatra‐Andaman and Southern Sumatra in the Sunda trench and Makran in the Northern Arabian Sea. Moreover, plausible worst‐case earthquake scenarios and respective fault parameters for each of these seismic zones have been recommended.

However, other potential tsunami sources such as seismic activity in the near‐field, submarine landslides and volcanic eruptions have not been considered.

Numerical simulations of tsunami propagation have been carried out for each of the four scenarios in order to assess the potential impact along the coastline of Sri Lanka. Such information relating to the spatial distribution of the likely tsunami amplitudes and arrival times for Sri Lanka would help authorities responsible for evacuation to make a better judgment as to the level of threat in different areas along the coastline, and act accordingly, if a large earthquake were to occur in any of the subduction zones in the Indian Ocean.

In the absence of comprehensive probabilistic assessments of the tsunami hazard to Sri Lanka, this paper's recommendations would provide the necessary framework for the development of deterministic tsunami hazard maps for the shoreline of Sri Lanka.

This paper aims to evaluate the vulnerability of typical low-rise reinforced concrete (RC) buildings located in Indonesia subjected to tsunami loading.

The vulnerability of typical three-story RC buildings located in Indonesia subjected to tsunami loading is discussed using fragility curves. Buildings without openings in all stories and buildings with openings in the first story are considered. The fragility curves are obtained by performing tsunami pushover analysis for several load cases, using different tsunami load estimation standards and references. The generalized linear method is used as a curve fitting method to construct the fragility curves.

The fragility curves show that the three-story RC buildings without openings in all stories subjected to tsunami loading have a high probability of collapse. Openings in the first story will reduce the vulnerability of the buildings.

Fragility curves are obtained by carrying out tsunami pushover analysis to evaluate the vulnerability of typical three-story RC buildings located in Indonesia. The results of this study show the need to include tsunami loads in the design code for Indonesian buildings and the benefits of having openings in the first story of the building.