The effects of a large destructive local earthquake on earthquake preparedness as assessed by an earthquake preparedness scale

A multi-act scale for measuring the earthquake preparedness of individuals and small businesses was developed and used to assess the earthquake preparedness and the perceived difficulty of becoming prepared for earthquakes of 291 University of Southern California undergraduate students approximately 3 weeks prior to the 5.9 magnitude Whittier Narrows earthquake on 1 October 1987. These data were then compared with similar information collected over a 2 1/2 month period following the earthquake from randomly selected samples of subjects that had participated in the original survey. In one case, levels of preparedness of a single group were measured at approximately 2 week intervals (the repeated measures study). In a second case, this information was collected at different points in time following the earthquake from different groups of subjects (the between groups study). Results indicated an initial increase in earthquake preparedness which was significant for subjects in the repeated measures group and which approached significance for subjects in the between groups. This increase in preparedness was maintained for subjects in the repeated measure study but gradually declined to pre-earthquake levels for subjects in the between subjects study. Subjects in the repeated measures study also perceived earthquake preparedness as a significantly less difficult task following the earthquake. Level of perceived difficulty continued to decline over the 2 1/2 month study period. Declines in perceived difficulty for the between subjects study were more erratic, and were only approximately 1/3 of that for the repeated measures group at the end of 2 1/2 months.     

How ready is ready? Measuring physical preparedness for severe storms

This paper investigates use of inventories, or checklists of activities, as an emergency management tool to motivate preparedness action in individuals. It develops the inventory concept to provide the foundation for a more targeted approach to storm preparation communication and community engagement. It also examines the potential efficacy of alternatives to paper-based checklists, such as web or smartphone applications. Academic and grey literature was reviewed to collect activities for a storm inventory for emergency agencies to measure individual preparedness and for individuals to measure their preparation progress. The resulting master list was refined for application and tested for useability in a pilot study of semi-structured interviews in a storm-susceptible community in Queensland, Australia. Also, clustering items by type of preparedness activity reveal where strengths and weaknesses exist in individual preparedness. For instance, preparation for leaving and safety planning were shown to be the areas of weakest activity in the pilot sample, while preparation of the house for a storm was the strongest area. In addition, behaviour change literature shows potential for effective use of an inventory-based smartphone application in motivating preparation activity. Data collected by a storm preparedness smartphone application could show where a communication or engagement program for targeted communities should be focused. It is supported by health literature that identifies preferences of individuals to make progress on complex tasks in stages, the value of lists to achievement of goals and demonstrated increase in uptake of activities prompted by smartphone applications over web or paper-based diaries.

     

A model of household preparedness for earthquakes: how individuals make meaning of earthquake information and how this influences preparedness

One way to reduce the risk from earthquakes is for individuals to undertake preparations for earthquakes at home. Common preparation measures include gathering together survival items, undertaking mitigation actions, developing a household emergency plan, gaining survival skills or participating in wider social preparedness actions. While current earthquake education programmes advocate that people undertake a variety of these activities, actual household preparedness remains at modest levels. Effective earthquake education is inhibited by an incomplete understanding of how the preparedness process works. Previous research has focused on understanding the influence individual cognitive processes have on the earthquake preparedness process but has been limited in identifying other influences posed by the wider social contextual environment. This project used a symbolic interactionism perspective to explore the earthquake preparedness process through a series of qualitative interviews with householders in three New Zealand urban locations. It investigated earthquake information that individuals are exposed to, how people make meaning of this information and how this relates to undertaking actual preparedness measures. During the study, the relative influence of cognitive, emotive and societal factors on the preparedness process was explored and the interactions between these identified. A model of the preparedness process based on the interviews was developed and is presented in this paper.     

Predicting community earthquake preparedness: a cross-cultural comparison of Japan and New Zealand

This paper reports on a study investigating cross-cultural equivalence in predictors of earthquake preparedness. Data were collected from Napier (New Zealand) and Kyoto (Japan). These locations were selected because they face comparable levels of seismic risk but differ with respect to their cultural characteristics. This mix of hazard similarity and cultural differences provided an opportunity to assess the degree of cross-cultural equivalence in predictors of earthquake preparedness. Cross-cultural equivalence was examined by assessing the degree to which individual hazard beliefs (outcome expectancies) and social characteristics (community participation, collective efficacy, empowerment, trust) could explain levels of hazard preparedness in each location. Structural equation modelling analyses revealed similarity in the pattern of relationships between predictor variables and intention prepare in the Napier and Kyoto data. It is argued that this provides support for the existence of some universal, cross-cultural equivalence in how hazard beliefs and social characteristics interact to predict the degree to which people adopt earthquake preparedness measures. Differences between the data sets are discussed in the context of the fundamental cultural differences between Japan and New Zealand. The theoretical and practical implications of the findings are discussed.     

The comparison analysis of Chinese public perception of earthquakes on different time scales

China has suffered from severe earthquake disasters in recent years. In order to explore the impact of severe earthquakes on public risk perception on different time scales, four surveys were conducted twice each after the severe Wenchuan and Yushu earthquakes. t tests were performed between two consecutive surveys to explore the change of public risk attitudes. The results demonstrated that after the two severe earthquakes, the public seismic risk acceptance has increased over time, and the comparison between pre- and post-Yushu earthquake illustrated that the severe disaster had more impact on vulnerable population such as females, children and low-income people. Moreover, linear regression models were employed to find the determining factors of public acceptance towards earthquake risks. It was discovered that the public perceived earthquake effect had significant negative relationship with seismic risk acceptance, and public trust towards local government had positive relationship with the risk acceptance. This study could help government to gain better understanding of public mental status and take more effective disaster preparedness measures when preventing and responding to a severe earthquake.     

Tsunami evacuation behavior of coastal residents in Kochi Prefecture during the 2014 Iyonada Earthquake

The 2014 Iyonada Earthquake, which occurred at 02:06 JST on 14 March, measured 6.2 on the Richter scale and originated in the Seto Inland Sea of Japan. To elucidate tsunami evacuation behavior, we examined two coastal communities in Kochi Prefecture, Okitsu and Mangyo, where residents evacuated to high ground in anticipation of a tsunami. In the event of a Nankai megathrust earthquake and tsunami, it is expected that a huge tsunami will be generated and these communities will be severely damaged. Before the Iyonada Earthquake, we had previously collected data about tsunami preparedness and evacuation plans from the residents of these communities, and after the earthquake, we conducted in-depth interviews and questionnaire surveys with the residents regarding the actual evacuation behaviors that they took. This enabled us to compare evacuation plans with evacuation behaviors. Results indicate that many residents responded quickly to the earthquake, either by immediately evacuating to emergency shelters on high ground or by preparing themselves for evacuation. Additionally, the earthquake revealed great differences between the prior evacuation plans and the actual situation of residents’ evacuation, such as specific triggers that significantly led residents to evacuate and the use of vehicles in evacuation.     

Analysis of Time of Occurrence of Earthquakes: A Functional Data Approach

There is no single method available for estimating the seismic risk in a given area, and as a result most studies are based on some statistical model. If we denote by Z the random variable that measures the maximum magnitude of earthquakes per unit time, the seismic risk of a value m is the probability that this value will be exceeded in the next time units, that is, R(m)=P(Z>m). Several approximations can be made by adjusting different theoretical distributions to the function R, assuming different distributions for the magnitude of earthquakes. A related method used to treat this problem is to consider the difference between the times of occurrence of consecutive earthquakes, or inter-event times. The hazard function, or failure rate function, of this variable measures the instantaneous risk of occurrence of a new earthquake, supposing that the last earthquake happened at time 0. In this paper, we will consider the estimation of the variable that measures the inter-event time and apply nonparametric techniques; that is, we do not consider any theoretical distribution. Moreover, because the stochastic process associated with this variable can sometimes be non-stationary, we condition each time by the previous ones. We then work with a multidimensional estimation, and consider each multidimensional variable as a functional datum. Functional data analysis deals with data consisting of curves or multidimensional variables. Nonparametric estimation can be applied to functional data, to describe the behavior of seismic zones and their associated instantaneous risk. The applications of estimation techniques are shown by applying them to two different regions and data catalogues: California and southern Spain.     

Effects of providing measures against earthquakes: experimental studies on the perceived risks of disasters and disaster preparedness intentions in Japan

This research examined the effects of providing measures against disasters on recipients’ perceived risks and preparedness intentions by conducting two experimental studies. A provision of a set of emergency food was manipulated in the first experiment. Participants (N = 143) were randomly assigned to the provided condition or non-provided condition. In the second experiment (N = 123), provision of an emergency toilet kit was manipulated. The results of the two experiments consistently indicated that (1) the provision of a measure increased the recipients’ perceived risks of the disaster concerned, (2) it increased their preparedness intentions for the disaster, and (3) it had no effects on perceived risks of or preparedness intentions against disasters unrelated to the measure provided. These results were contrary to the prediction deduced from the protection effect and single action effect. The findings in this study encourage promoting the risk management policy of providing people with disaster measures as the first step in disaster preparedness.     

Evaluation of public participation in reconstruction of Bam,Iran, after the 2003 earthquake

In the midst of the ever-increasing natural and human-induced disasters, where many of the preparedness and mitigation measures show inefficiencies, there is narrow margin for decision-makers to make mistakes by misallocating budgets, designing infeasible reconstruction plans, and in other terms, making decisions not in line with the public preferences. In particular, public participation in post-disaster measures seems undoubtedly necessary to reduce the possible economic, social, political, and cultural conflicts around the stressful community after a major disaster. This paper aims at evaluating the role of public participation in increasing the reconstruction phase efficiency through a case study of the reconstruction process in Bam, a southeastern Iranian city, after the 2003 earthquake. It is attempted to identify the major motivators of the public participation through a combination of quantitative and qualitative studies. Statistical data are generated through a set of questionnaires being filled by a number of 200 randomly selected survivors. The numerical results were then discussed through the Focus Group technique sessions to determine the main contributors to the public participation. It is later found that the answers are found among the performance of the reconstruction authorities, financial policies, emotional resiliency of the survivors, public information mechanisms, public satisfaction, the pace of reconstruction, and temporary housing policies.     

An Alternative Measure of the Reliability of Ordinary Kriging Estimates

This paper presents an interpolation variance as an alternative to the measure of the reliability of ordinary kriging estimates. Contrary to the traditional kriging variance, the interpolation variance is data-values dependent, variogram dependent, and a measure of local accuracy. Natural phenomena are not homogeneous; therefore, local variability as expressed through data values must be recognized for a correct assessment of uncertainty. The interpolation variance is simply the weighted average of the squared differences between data values and the retained estimate. Ordinary kriging or simple kriging variances are the expected values of interpolation variances; therefore, these traditional homoscedastic estimation variances cannot properly measure local data dispersion. More precisely, the interpolation variance is an estimate of the local conditional variance, when the ordinary kriging weights are interpreted as conditional probabilities associated to the n neighboring data. This interpretation is valid if, and only if, all ordinary kriging weights are positive or constrained to be such. Extensive tests illustrate that the interpolation variance is a useful alternative to the traditional kriging variance.     

A two‐invariant pseudoelastic model for reservoir compaction

Predicting the deformations of deep reservoirs due to fluid withdrawal/injection is a challenging task that could have important environmental, social, and economical impacts. Finite element models, if endowed with an appropriate constitutive law, represent a useful tool for computing the displacements, the deformations, and the stress distributions in reservoir applications. Several studies show that hypoelastic laws, based on a stress‐dependent vertical compressibility, are able to provide accurate results, confirmed by in situ and satellite measurements. On the other hand, such laws present some weaknesses related to the numerical implementation, in particular due to the nonsymmetry of the tangent operator. This paper presents a new constitutive model based on 2 invariants (the mean normal and deviatoric stresses), characterized by a variable pressure‐dependent bulk modulus K. This constitutive law allows for overcoming most shortcomings of the hypoelastic law, although preserving the same accuracy, reliability, and ease of use and calibration. This paper presents a procedure to identify the parameters of the new model, starting from the typically available data on the vertical compressibility. Numerical results show a good agreement between the 2 laws, suggesting the proposed approach as a valid alternative in reservoir applications.     

Quantitative analysis of earthquake fatalities: case of Iran

Earthquakes in Iran are major and chronic disasters, but there is a seemingly downward trend in the number of lives lost from earthquake disasters in the past five decades. This paper particularly examines whether factors such as urbanization, literacy rate, wealth, and retrofitting measures have contributed to the declining trend of fatalities over past decades. Data records of 1960–2010 have been used to demonstrate the fatalities trend and a shorter series of 1990–2010 has been used to carry out a statistical analysis due to limited availability of information on retrofitting practices in the country. Regression models run in two stages. The first stage consists of normalized fatalities of Iran’s earthquakes, regressed on urbanization, wealth, and retrofitting. The second stage involves the measure of retrofit as the dependent variable regressed over urbanization and/or wealth as explanatory variables. The resulted regression models clearly explain the importance of retrofitting measure in saving lives in earthquakes disasters, as well as providing economic advantages and robust environment to the population. The study provides significant guidance for public policy. Undoubtedly, retrofitting, started in the country from 1990, has decreased the number of deaths; nonetheless, the measure is found to be mostly enforced in the cities and not in rural areas. Decision makers can use the results of this study to prioritize retrofit in rural areas, more than ever, and as much as possible.     

城市化防震减灾经济性研究

本文通过对东南沿海地震背景和地震破坏性经济损失,结合国内外城市化进程中防震减灾经济性对比研究,认为地震破坏的负面效应所带来的经济损失十分巨大。因而必须加强防震减灾工作为保障城市化顺利发展服务。     

Implementation of an integrated vulnerability and risk assessment model

An integrated vulnerability and risk assessment model (IVR) is proposed. The proposed model is a composite index that assesses the relationships among four critical components, namely exposure, hazard, vulnerability and capacities and measures, and how these can be used to illustrate the integrated risk and vulnerability situation of an area. These factors are assessed using individual variables. Fifty-four variables, objectively decided upon, were used to measure the contribution of each component factor. The general characteristics of vulnerability, risk, exposure and capacities and measures are well known; however, the relative importance of each variable and their inter-relatedness, in measuring risk and vulnerabilities, as demonstrated by the IVR; and how these in turn affect the impacts of natural hazards, are still debatable. The IVR though provides a valid, reliable and sensitive tool, which can be used to further explore these relationships. Through robust testing and application, subjectivity in the selection of variables can be reduced. Moreover, through the establishment of a database for data collection and storage, objectivity (reliability) can be achieved as well as, availability of the requisite data inputs. The sensitivity of the model allows for the quick identification of strategic action, which will ultimately lead to hazard loss reduction. The values yielded for each component factor can help decision-makers in the allocation of scarce developmental funds as well as identify trends in levels of risk, vulnerability, exposures and capacities and measures as well as determine areas where mitigation strategies are needed most.     

On the Use of Non-Euclidean Distance Measures in Geostatistics

In many scientific disciplines, straight line, Euclidean distances may not accurately describe proximity relationships among spatial data. However, non-Euclidean distance measures must be used with caution in geostatistical applications. A simple example is provided to demonstrate there are no guarantees that existing covariance and variogram functions remain valid (i.e. positive definite or conditionally negative definite) when used with a non-Euclidean distance measure. There are certain distance measures that when used with existing covariance and variogram functions remain valid, an issue that is explored. The concept of isometric embedding is introduced and linked to the concepts of positive and conditionally negative definiteness to demonstrate classes of valid norm dependent isotropic covariance and variogram functions, results many of which have yet to appear in the mainstream geostatistical literature or application. These classes of functions extend the well known classes by adding a parameter to define the distance norm. In practice, this distance parameter can be set a priori to represent, for example, the Euclidean distance, or kept as a parameter to allow the data to choose the metric. A simulated application of the latter is provided for demonstration. Simulation results are also presented comparing kriged predictions based on Euclidean distance to those based on using a water metric.     

Observations from the 12 October 1992 Dahshour earthquake in Egypt

An earthquake of local magnitude 5.3 (duration magnitudeM _d ) on the Richter Scale occurred at Dahshour, 18 km south of Cairo, Egypt, on Monday, 12 October 1992 at 3:09 pm (local time). Numerous aftershocks followed the main event during the following weeks with magnitude up to 4.3. The earthquake occurred in an area that has had no recent seismic activity, and affected many cities in Egypt. Many buildings and monuments were severely damaged or collapsed. Modern concrete skeletal structures suffered minor nonstructural damage. Earthquake physical damage was estimated at about one billion U.S. Dollars. The severity of the damage was mainly due to poor construction materials and detailing, aging, inferior workmanship, and inadequate maintenance. Egypt was generally considered to be an area of moderate seismic activity. In 1989, earthquake provisions were first introduced in the Egyptian Code of Practice for Reinforced Concrete Structures only. The earthquake clearly showed the urgent need for an assessment and rehabilitation program to mitigate seismic risk hazard in existing structures. In addition, future development planning, and earthquake preparedness strategies should implement lessons learned from the event. In this paper, an overview discussion about the observations from the 12 October earthquake is presented.     

Magnitude conversion problem for the Turkish earthquake data

Earthquake catalogues which form the main input in seismic hazard analysis generally report earthquake magnitudes in different scales. Magnitudes reported in different scales have to be converted to a common scale while compiling a seismic data base to be utilized in seismic hazard analysis. This study aims at developing empirical relationships to convert earthquake magnitudes reported in different scales, namely, surface wave magnitude, M _S, local magnitude, M _L, body wave magnitude, m _b and duration magnitude, M _d, to the moment magnitude (M _w). For this purpose, an earthquake data catalogue is compiled from domestic and international data bases for the earthquakes occurred in Turkey. The earthquake reporting differences of various data sources are assessed. Conversion relationships are established between the same earthquake magnitude scale of different data sources and different earthquake magnitude scales. Appropriate statistical methods are employed iteratively, considering the random errors both in the independent and dependent variables. The results are found to be sensitive to the choice of the analysis methods.     

Physical meaning of deviation of some parameters from the similarity law in a seismic process

An experimentally substantiated explanation is proposed for recently discovered specific regularities between the time of earthquake preparation and the earthquake scale. It is shown that the observed regularity of the time of earthquake preparation, which grows slowly with the scale as compared with what follows from the relations for the self-similar environment, may be governed by the nonlinear scale dependence of specific stiffness of discontinuities that demonstrates a gradual increase in the effective elastic modulus of fault zones as their typical size grows.     

Accessibility, mobility and transport-related welfare: the case of rural wales

The welfare of rural communities depends to a large extent on standards of mobility and accessibility to (mainly urban) services. Probably the most valid measure is based on the needs and time/space budgets of specific population groups in specific villages (MOSELEY et al., 1977). For policy applications, there is a need for a way of evaluating ‘personal accessibility’ over a broader region rather than the detailed local case studies which such methods demand. A series of maps depicting aspects of accessibility and mobility is constructed for Rural Wales, at a parish level. The problem of weighting is potentially intractable, but it is argued that a simple points system is acceptable in combining these measures into a composite index.     

Quantifying the role of sandy–silty sediments in generating slope failures during earthquakes: example from the Algerian margin

The Algerian margin is a seismically active region, where during the last century, several large magnitude earthquakes took place. This study combines geotechnical and sedimentological data with numerical modelling to quantitatively assess the present-day slope stability of the Algerian margin. Geotechnical laboratory tests, such as cyclic triaxial tests, oedometric tests and vane shear tests were carried out on sediment cores collected on the study area. The liquefaction potential of a sediment column located about 30 km from the Boumerdès earthquake epicentre of 21st May 2003 was evaluated theoretically for an earthquake of M _w  = 6.8. We show that thin sand and silt beds such as those described on recovered sediment cores are the main cause of sediment deformation and liquefaction during earthquakes. Numerical calculations showed that the slope failure may occur during an earthquake characterised by a PGA in excess of 0.1g, and also that, under a PGA of 0.2g liquefaction could be triggered in shallow silty–sandy deposits. Moreover, comparison of the predicted slope failure with failure geometries inferred from seafloor morphology showed that earthquakes and subsequent mass movements could explain the present-day morphology of the study area.