Measuring vulnerability to natural hazards: a macro framework

The measurement of vulnerability—defined here as the asymmetric response of disaster occurrences to hazardous events—signifies a key step towards effective disaster risk reduction and the promotion of a culture of disaster resilience. One of the reasons for not being able to do the same in a wider context is related to conceptual, definitional, and operational issues. This paper presents an operationally feasible framework for conducting this task and measures revealed macro vulnerability as a function of disaster risk and hazard probability. The probabilities of hazard and its perceived disaster risk were obtained from past data and from probability distributions. In this paper, the corresponding analytical framework is constructed using the case study of floods in Assam, India. The proposed indicator will help policymakers to draw on available macro‐level data to identify the regions that are vulnerable to disasters, where micro‐level disaster vulnerability assessments could be performed in greater detail.     

Constructing vulnerability: the historical, natural and social generation of flooding in metropolitan Manila

Flooding is not a recent hazard in the Philippines but one that has occurred throughout the recorded history of the archipelago. On the one hand, it is related to a wider global ecological crisis to do with climatic change and rising sea levels but on the other hand, it is also the effect of more localised human activities. A whole range of socio-economic factors such as land use practices, living standards and policy responses are increasingly influencing the frequency of natural hazards such as floods and the corresponding occurrence of disasters. In particular, the reason why flooding has come to pose such a pervasive risk to the residents of metropolitan Manila has its basis in a complex mix of inter-relating factors that emphasise how the nature of vulnerability is constructed through the lack of mutuality between environment and human activity over time. This paper examines three aspects of this flooding: first, the importance of an historical approach in understanding how hazards are generated; second, the degree of interplay between environment and society in creating risk; and third, the manner in which vulnerability is a complex construction.     

Understanding the causes of vulnerabilities for enhancing social-physical resilience: lessons from the Wenchuan earthquake

ABSTRACT

In an effort to understand the social-physical vulnerabilities from the 2008 Wenchuan earthquake, this research established and validated a conceptual model for natural disaster analysis. The earthquake severely impacted the built environment, with many buildings being destroyed in the earthquake and from secondary impacts. This vulnerable environment exacerbated the poverty in the local residents because of the lack of flat land and the inaccessibility of the mountainous areas. Therefore, there was an interactive relationship between the built environment vulnerability and the social vulnerability. Due to general poverty and low education levels, social vulnerability in rural areas is often the result of poor quality building construction; in the event of an earthquake, therefore, most economic losses and casualties are the result of building destruction. To enhance social-physical resilience, measures should be adopted to mitigate the vulnerability of the built environment and society through actions such as land use planning, the use of seismic-resistant technologies, and investment in infrastructure, education, industrial development, and environmental protection. This research extracts the reasons for the vulnerabilities through an examination of the interactions between the natural environment, the built environment, and the local society. The insights gained have significant theoretical and practical implications in assisting vulnerable communities resist and adapt to natural hazards to achieve sustainable development.     

Are non‐poor households always less vulnerable? The case of households exposed to protracted civil war in Southern Sudan

Civil wars in Africa are now the leading contributory cause of vulnerability of rural communities. Understanding vulnerability during civil war is critical for humanitarian response and post-conflict rehabilitation planning. The lack of understanding of vulnerability has led existing studies to make sweeping generalizations, either by equating the dynamics of vulnerability during civil wars with vulnerability in other risk events, or by projecting people in the 'war zones' as unable to cope and subsequently becoming vulnerable. This paper is an attempt to gain a more nuanced understanding of the dynamics of vulnerability during protracted civil war. It shows that during civil war the non-poor are not necessarily less vulnerable than poor households. The idea that people caught up in civil war are all vulnerable is not supported by the findings of this paper. It shows that the 'standard' pattern of vulnerability to drought is similar to that during exogenous counter-insurgency warfare, while a different pattern of vulnerability to endogenous shocks is identified.     

Environmental knowledge and human experience: using a historical analysis of flooding in Ireland to challenge contemporary risk narratives and develop creative policy alternatives

Focusing on three of the largest coastal cities in the Republic of Ireland, this paper highlights the importance of a historical analysis of flood hazards in contextualising current events and potential future risks. Over the last decade, the cities of Dublin, Cork and Galway have experienced several major coastal, river and pluvial floods. In the aftermath of these floods, two distinct but related narratives have dominated public discourse and official responses. The first narrative presents recent floods as unprecedented and as possible evidence of climate change. The second constructs floods primarily as natural events and assumes that the optimal means of reducing flood losses is to prevent flood events. In this paper, I suggest that these narratives are not supported by a historical analysis of exposure and vulnerability to flood hazards in Irish cities. This paper draws primarily on newspaper archives to construct a record of past flooding that challenges these narratives in several ways and in doing so offers lessons for similar cities in other countries. I contend that these narratives are perpetuated by a narrow form of knowledge production (quantitative risk assessment) and a narrow range of data (numeric instrumental records). Incorporating a broader range of sources and data types into risk and vulnerability assessments may illuminate more creative strategies for reducing both contemporary and future flood losses.     

Rural residents and choice of building earthquake-resistant house: results of a choice experiment study

Rural settlements, especially in developing countries, are disproportionally vulnerable to natural hazards due to both biophysical and social vulnerability. Building hazard-resistant houses requires a thorough understanding of hazards and institutional and financial resources. However, it is equally important for planners and policymakers to know how rural residents make the tradeoff between various housing attributes when provided with the resources such as low-interest housing construction loans. In this study, we use a choice experiment (CE) to examine rural households' preference for earthquake resistance when building houses. A total of 300 households from randomly selected villages in central districts of Guilan Province in Iran were recruited for a CE study in which they had to choose between a number of houses that differed in terms of the required construction loan, resistance to earthquakes, size, and exterior and interior designs. Our results show that the average resident preferred larger houses with better exterior and interior designs to more earthquake-resistant houses, and is willing to spend more on these attributes than earthquake safety. These results indicate that rural households are willing to receive loans to improve their houses but that this does not translate into more earthquake-resistant houses.     

基于GIS的气候变化对马铃薯生长的脆弱性评价

利用层次分析和专家打分法构建了气候变化对内蒙古马铃薯生产的脆弱性影响评价指标体系,运用脆弱性的定义及灾害风险的理论建立了马铃薯脆弱性综合指数评估模型,通过分析主产区的敏感性、适应性来评估脆弱性影响程度。结果表明:内蒙古马铃薯生产脆弱性分布呈中部高、东西部低的分布特点。以乌兰察布市中部、呼和浩特市南部、包头市南部及锡林郭勒盟西南部脆弱性为最高;呼伦贝尔市、兴安盟、通辽市及鄂尔多斯市南部脆弱性为最低;赤峰市大部、巴彦淖尔市及鄂尔多斯市北部为中等。针对主产区马铃薯生长脆弱性的成因,提出了应分别采取不同的应对措施。研究结果可为自治区马铃薯生产可持续发展提供科学依据。     

Cyclone mitigation, resource allocation and post-disaster reconstruction in south India: lessons from two decades of research

This paper opens with a history of development and disaster-prevention strategies in a cyclone-prone area of the east coast of India and traces the evolution in the area of British and Indian governments' programmes and policy over a century. Research over the last 20 years has shown, however, that the programmes and policies have failed to balance economic growth with safety. Resources intended for the benefit of all have been diverted by alliances of powerful people to a small minority, and recent developments have reduced the physical protection of the area. The result is that increasing numbers of people are vulnerable to the effects of cyclones and floods. The findings suggest that the best way to reduce vulnerability is to improve the socio-economic standing of the most vulnerable and for this to happen these people must have an assured income based on assets that will enable them to acquire social and economic credit-worthiness within the local economy. This paper presents evidence that suggests that non-governmental organisation (NGO)-supported co-operatives are the best way to achieve this through self-help and self-employment schemes. It also suggests that NGOs should be encouraged to take up environmentally and ecologically beneficial activities involving the poorest groups in the communities, in this way combining sustained self-employment with environmental protection.     

基于神经网络模型的房屋震害易损性估计方法

结构易损性分析是震害预测工作中的一个重要环节.本文提出了一种基于人工神经网络模型的房屋震害易损性估计方法,文中以多层砖房结构的建筑为例,给出了易损性估计神经网络模型的输入向量设计方案和具有输出约束控制的BP神经网络模型.     

家户水灾社会脆弱性的评估方法研究——以长沙地区为例

中国是洪水灾害发生频繁的国家之一，研究水灾脆弱性对中国的灾害风险管理有着极为重要的意义。但是，合理评估脆弱性尤其是社会脆弱性却面临着极大的挑战。利用Hoovering改进模式，选择湘江流域的长沙地区为研究区，对研究区内的家户进行了社会脆弱性评价。结果表明，长沙市区的5个区内，高脆弱性家户最多的是天心区，最少的是雨花区。而就社区而言，高脆弱性家户最多的足裕南街街道和桔子洲街道。该结果反映了长沙不同行政区、社区社会脆弱性的差别，可供确定受援地区和受援人群及开展援助活动，乃至灾后日常风险管理参考。     

PRE-ESTIMATE FOR THE CHANGE OF CLIMATIC VULNERABILITY TO AGRICULTURAL PRODUCTION IN LOESS PLATEAU,CHINA

Inrecentyears ,inthebackgroundofstrongglobalenvironmentalchange ,naturalvariationhastheaggravatingtendencyyearbyyearinChina .Additionally ,Chinahasahigheconomicgrowthrateandagreatpopulation ;humanactivitiesinhighriskareas (likeLoessPlateau)areexacerbated ;andbearingcapabilityagainstthedisasterisgenerallyvulnerable .Becauseofthosefactorsabove ,theeconomiclossescausedbythedisastershavebeenincreasing .Therefore ,ithasbecomethescientificbasisofestablishingaregionalsustainabledevelopmenttoprobein…     

Modelling the elements of country vulnerability to earthquake disasters

Earthquakes have probably been the most deadly form of natural disaster in the past century. Diversity of earthquake specifications in terms of magnitude, intensity and frequency at the semi-continental scale has initiated various kinds of disasters at a regional scale. Additionally, diverse characteristics of countries in terms of population size, disaster preparedness, economic strength and building construction development often causes an earthquake of a certain characteristic to have different impacts on the affected region. This research focuses on the appropriate criteria for identifying the severity of major earthquake disasters based on some key observed symptoms. Accordingly, the article presents a methodology for identification and relative quantification of severity of earthquake disasters. This has led to an earthquake disaster vulnerability model at the country scale. Data analysis based on this model suggested a quantitative, comparative and meaning full interpretation of the vulnerability of concerned countries, and successfully explained which countries are more vulnerable to major disasters.     

Understanding the interacting factors that influence social vulnerability: a case study of the 2016 central Italy earthquake

This paper seeks to identify those areas that proved socially vulnerable to the earthquake that struck central Italy on 24 August 2016. The study involved four key steps. First, six relevant social vulnerability indicators were selected, based on previous conclusions in the literature. Second, the indicators were mapped using the inverse distance weighted interpolation method. Third, social vulnerability was assessed according to a spatial combination of the indicators. Fourth, in order to build a heterogeneity map, another approach was employed to represent the spatial variability of social vulnerability and to provide additional information on the synergistic contributions of the indicators. The results indicate that age and accessibility indicators affect the entire region under review, with highly vulnerable zones being close to small historical centres. These findings will be useful to governments, policymakers, and stakeholders with regard to implementing vulnerability mitigation strategies in Italian territories that are highly susceptible to earthquake hazards.     

美国地震风险评估中建筑物易损性与损失组合的探讨

探讨了以美国地震灾害风险评估模型为例的建筑物易损性模型的建立方法及地震随机事件损失组合的方法.由于应用对象的不同,如用于工程项目风险的评估或是对保险资产风险的评估,其易损性模型建立的方式具有较大的差异.在工程应用中,注重对建筑结构的分析,往往使用非线性解析方法如能力频谱法等以得到结构的易损性或脆弱曲线；而保险行业常用历史数据并运用统计方法等获取所需的易损性曲线.由于工程应用的易损性曲线有更好的精准性,越来越多保险用模型采用此方法.此外,工程应用常对单一地震事件进行评估,而保险行业的模型往往涉及对大量随机事件的评估.对不同的建筑物易损性建模方法、规范标准及适用范围进行了探讨,并对随机事件损失组合方法中如何计算损失的单次超越概率(OEP)和累计超越概率(AEP)进行了介绍.     

Tsunami survivors' perspectives on vulnerability and vulnerability reduction: evidence from Koh Phi Phi Don and Khao Lak, Thailand

This paper presents the results of primary research with 40 survivors of the 2004 Indian Ocean tsunami in two communities: Khao Lak (n=20) and Koh Phi Phi Don (n=20), Thailand. It traces tsunami survivors' perceptions of vulnerability, determines whether residents felt that the tsunami affected different communities differently, identifies the populations and sub-community groups that survivors distinguished as being more vulnerable than others, highlights community-generated ideas about vulnerability reduction, and pinpoints a range of additional vulnerability reduction actions. Tsunami survivors most consistently identified the 'most vulnerable' community sub-populations as women, children, the elderly, foreigners, and the poor. In Khao Lak, however, respondents added 'Burmese migrants' to this list, whereas in Koh Phi Phi Don, they added 'Thai Muslims'. Results suggest that the two case study communities, both small, coastal, tourism-dominated communities no more than 100 kilometres apart, have differing vulnerable sub-groups and environmental vulnerabilities, requiring different post-disaster vulnerability reduction efforts.     

Flood vulnerability and commercial activities: the case of the city of Girona, Spain

This paper is based on a case study of the city of Girona in Catalonia, Spain, and analyses the vulnerability of commercial establishments to floods caused by the Onyar River. A mapping and statistical approach (cluster analysis) was applied to the information obtained from 568 questionnaires answered by the shops and the workshops located in the flood risk area. The results obtained allowed the authors to determine five different flood vulnerability profiles of the commercial establishments analysed. These profiles paint a picture of little individual adaptation to the risk and the possibility of suffering, sooner or later, large economic losses due to overflowing of the Onyar River. The authors established a methodology for carrying out a detailed multidimensional analysis of the flood vulnerability of the city's commercial establishments in order to provide the foundations for local government policies and for strategies for shop owners to reduce flood vulnerability.     

城市建筑物抗震能力评估方法

由于建筑物震害预测方法只能估计建筑物的破坏而不能评定建筑物的抗震能力,基于对城市建筑物潜在破坏的估计,提出了城市建筑物抗震能力的评估方法。影响城市建筑物抗震能力的因素包括城市所处的地震危险性环境和城市建筑物的易损性。为了考虑地震危险性因素,进行了以地面峰值加速度(PGA)为参数的地震危险性分析,提出了我国不同地震危险性特征分区的PGA概率密度函数;为了考虑建筑物的易损性因素,采用HAZUS-MH中的静力弹塑性分析(push-over anal-ysis)方法研究群体建筑物易损性。通过对这两个因素的研究,建立了城市建筑物抗震能力评估方法,提出的相对全概率抗震能力指数可以反映城市建筑物在其所在的地震危险性环境下所具有的抗震能力,而采用绝对全概率抗震能力指数能够比较不同建筑抗震能力的差异,再结合建筑物抗震能力评估标准,可确定抗震能力水平。以晋江市抽样建筑物抗震能力评估为例,结合震害经验,论证了该方法的有效性。     

Targeting the Vulnerable: A Review of the Necessity and Feasibility of Targeting Vulnerable Households

This article examines whether it is possible to target vulnerable households within a geographically defined area. It looks first at the justification for targeting and then reviews recent practical experience in actually trying to reach vulnerable groups. As complex emergencies increasingly last longer, strategies to target vulnerable households are common in the protracted phase of the emergency. While this is often necessary because of a decline in resources, it is not always justified by an improvement in nutritional status or food security of the beneficiary population.
Common target groups are the poor and the malnourished, but in complex emergencies these are not always the most vulnerable. Moreover, recent practical experience has shown considerable difficulties in targeting the poor. Methods to target the poor rely on community-based relief committees, whose priorities are not necessarily the same as those of external agencies. This paper gives examples of such targeted assistance programmes in Kenya, south Sudan and Tanzania. The paper concludes that situations where targeting vulnerable households is justified and feasible are extremely limited. It is suggested that if targeting has to be done because of scarce resources, this should be done on a geographical basis and on the basis of nutritional status. Case-study material shows that it is essential to understand the political determinants of vulnerability and to design methods that will reach the most vulnerable.     

Attitude before method: disability in vulnerability and capacity assessment

Many agencies working on disaster risk reduction use vulnerability and capacity assessment (VCA) to identify vulnerable groups, to assess their needs and capacities, and to develop appropriate programmes and policies. In theory, VCA offers a good opportunity to incorporate disabled people's needs and resources in counter‐disaster programming. This paper seeks to establish and explain the extent to which disability is included in VCA in practice. It reviews VCA reports and findings, formal VCA guidance, and other methodological literature. The review indicates that disability is a neglected issue in VCA practice and that manuals and guidelines, while promoting the general ideal of inclusiveness, are insufficiently aware of the challenges to achieving this in practice and do not offer enough guidance on how to reach and include disabled people. Ways of overcoming these problems are suggested. However, the real challenge may be to change core attitudes and perceptions of disability within implementing organisations.     

自然灾害的社会易损性及其影响因素研究

社会易损性是人类社会在自然灾害条件下的潜在损失,它的大小受许多因素的影响。从社会学视角出发,从人口、社会结构和社会文化三方面分析了社会易损性的影响因素,它们包括易损人群、易损职业、社会经济活动、社会组织结构、社会资本、社会保障制度、社会冲突的协调能力和灾害文化等因素。