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Indices of Social Vulnerability to Natural Hazards: A Comparative Evaluation

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  • Arizona State University, Phoenix, United States
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... The reason is that indices are "measure(s) of an abstract theoretical construct in which two or more indicators of the construct are combined to form a single summary score" (Carmines and Wood, 2004: 485). Indices are beneficial measures since they condense a complex reality into simple terms (Diener and Suh, 1997;Gall, 2007). Recent studies on climate change vulnerability have attempted to develop global level, general vulnerability indicators for climate change assessment. ...
... Others have cited difficulties in the interpretation of indices (Eakin and Luers, 2006, p. 377). Similarly, Gall (2007) attempted to compare seven national-level indices of social vulnerability to climate change with a particular focus on natural hazards. The indices from various sources and fields of practice (see Table 1) include: the Human Development Index (HDI) of the UNDP; Human Wellbeing Index (HWI) by Prescott-Allen (2001); Prevalent Vulnerability Index (PVI) by Cardona (2007); the Index of Social Vulnerability to Climate ...
... In this study, Gall (2007) suggested that there are "significant shortcomings in the construction of most of the evaluated indices with particular gaps in empirical validity and methodological robustness" (p.vi). She noted further that the key issues that "shape the variability and uncertainty contained in the current vulnerability indices are: "subjective interpretation of vulnerability concepts, ignorance of sound statistical practices, limited data availability, and absence of reliable approaches to calibrate social vulnerability indices" (Ibid.), a position we strongly share in this study. ...
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In order to make a good assessment of vulnerability to climate change, it is im- portant first, to distinguish between weather and climate, climate variability and climate change. This is also necessary for the development of an effective meth- odology and good assessment tools for vulnerability analysis. While weather refers to daily observed atmospheric conditions, particularly temperature, humidity, pre- cipitation and air movements and/or quality; climate is much more complex and “scientific”. Climate refers to aggregate weather conditions (temperature, precipita- tion, wind and other meteorological conditions) collected over a long period of not less than 30 years (UN-Habitat, 2012) that characteristically prevail in a particular region. It includes some variability in day-to-day, year-to-year, decade-to-decade conditions, known as weather cycles (WBI, 2013); as well as from place to place. Variability may be due to natural internal processes within the climate system (de- scribed as internal variability), or to variations in natural or anthropogenic external forces (external variability) (IPCC, 2001). Climate change describes the variations that persist for periods of 30 years or more in a region (Ibid). Here, the IPCC define climate change as the statistically significant variation of the climate due to natural or human related causes (IPCC, 2007; CARE, 2009). Humans and their activities are the most affected by climate change; hence, assessing what is likely to change, who are most likely to be impacted upon by climate change, and how those exposed to climate hazards are prepared to respond to the change become imperative. This is the concept of vulnerability and this study seeks to define a methodology that can characterise, assess and monitor local vulnerability to climate change.
... To date, very few attempts have been made to validate vulnerability index outcomes (Tate, 2012;Bakkensen et al., 2017). The most widely used approach so far is based on the use of independent proxy data referring to real observable outcomes, such as emergency service requests (Kontokosta and Malik, 2018), mortality (Adger et al., 2004;Gall, 2007;Peacock et al., 2010;Cardozo and Monteiro, 2019), building damage or losses (Peacock et al., 2010;Papathoma-Köhle, 2016;Papathoma-Köhle et al., 2019;Rufat et al., 2019), number of disasters (Cutter et al., 2003;Debortoli et al., 2017), post-event surveys (Fekete, 2009;Sherrieb et al., 2010) and qualitative information from focus groups (Oulahen et al., 2015). In other cases, validation is addressed by comparing results with other reference indices (Gall, 2007;Peacock et al., 2010;Sherrieb et al., 2010;Estoque and Murayama, 2014). ...
... The most widely used approach so far is based on the use of independent proxy data referring to real observable outcomes, such as emergency service requests (Kontokosta and Malik, 2018), mortality (Adger et al., 2004;Gall, 2007;Peacock et al., 2010;Cardozo and Monteiro, 2019), building damage or losses (Peacock et al., 2010;Papathoma-Köhle, 2016;Papathoma-Köhle et al., 2019;Rufat et al., 2019), number of disasters (Cutter et al., 2003;Debortoli et al., 2017), post-event surveys (Fekete, 2009;Sherrieb et al., 2010) and qualitative information from focus groups (Oulahen et al., 2015). In other cases, validation is addressed by comparing results with other reference indices (Gall, 2007;Peacock et al., 2010;Sherrieb et al., 2010;Estoque and Murayama, 2014). The approaches described above are included in what is known as external validation, and they are usually implemented J o u r n a l P r e -p r o o f when natural hazard impacts happen at regional or national scale (e.g. ...
... This is because the required data are not normally available (Fekete, 2009) and because flash flooding events are not simultaneously triggered in all urban areas of interest. Thus, an increasingly being used alternative is to validate vulnerability indices internally through an analysis of how changes in index inputs affect modeled results (Gall, 2007;Tate, 2012Tate, , 2013. Internal validation is usually performed by means of a sensitivity and uncertainty analysis, Monte Carlo simulations being the most frequently used approach (Davidson and Lambert, 2001;Gall, 2007;Tate, 2012Tate, , 2013, although other statistical tools such as correlation and regression analysis and cross-validation have also been employed (Schmidtlein et al., 2008;Cai et al., 2016;Anderson et al., 2019;Marzi et al., 2019;Nazeer and Bork, 2019). ...
... In response to the need to improve risk management and adaptation strategies, academics and . Therefore, vulnerability is also a function of 86 exposure (i.e., people and assets at risk), sensitivity (i.e., the level of impact on people and assets at 87 risk), and resilience (i.e., the ability of the social system to resist, absorb, cope with, adapt, and recover The most widely used methodology to analyze vulnerability so far is the development of results (Gall, 2007;Tate, 2012Tate, , 2013. Internal validation is usually performed by means of a sensitivity 134 and uncertainty analysis, Monte Carlo simulations being the most frequently used approach (Davidson 135 and Lambert, 2001; Gall, 2007;Tate, 2012Tate, , 2013, although other statistical tools such as correlation 136 and regression analysis and cross-validation have also been employed (Schmidtlein et Therefore, the goal of this paper is to construct and validate at regional scale an Integrated Socio- 139 Economic Vulnerability Index (ISEVI) in urban areas prone to flash flooding. ...
... Therefore, vulnerability is also a function of 86 exposure (i.e., people and assets at risk), sensitivity (i.e., the level of impact on people and assets at 87 risk), and resilience (i.e., the ability of the social system to resist, absorb, cope with, adapt, and recover The most widely used methodology to analyze vulnerability so far is the development of results (Gall, 2007;Tate, 2012Tate, , 2013. Internal validation is usually performed by means of a sensitivity 134 and uncertainty analysis, Monte Carlo simulations being the most frequently used approach (Davidson 135 and Lambert, 2001; Gall, 2007;Tate, 2012Tate, , 2013, although other statistical tools such as correlation 136 and regression analysis and cross-validation have also been employed (Schmidtlein et Therefore, the goal of this paper is to construct and validate at regional scale an Integrated Socio- 139 Economic Vulnerability Index (ISEVI) in urban areas prone to flash flooding. It considers all 140 vulnerability components (i.e., exposure, sensitivity and resilience) and it takes into account two of the 141 most influential dimensions in the urban environment (i.e., social and economic dimensions). ...
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Flash flooding is the natural hazard provoking the largest number of casualties, so adequately characterizing vulnerability is key to improve flood risk analysis and management. Developing composite indices is the most widely used methodology in vulnerability analysis. However, very few studies have so far assessed vulnerability in urban areas prone to flash flooding and the resulting research presents two main drawbacks: i) a fragmented approach is often pursued, i.e. without jointly considering the vulnerability components (exposure, sensitivity and resilience) and the two most influential dimensions in urban environments (social and economic); and ii) vulnerability indices are not usually validated because an ancillary dataset is not generally available and flash flooding events do not happen simultaneously in all urban areas of a particular region. Considering the above gaps, this paper describes the construction of an Integrated Socio-Economic Vulnerability Index (ISEVI) at the regional scale, which considers all vulnerability components and social and economic dimensions. ISEVI was subsequently validated through an uncertainty and sensitivity analysis using the Monte Carlo method. Further, regional spatial patterns of vulnerability were identified implementing a Latent Class Cluster Analysis. Uncertainty analysis reveals the high stability of vulnerability categories of the ISEVI and sensitivity analysis shows that the type and the conservation state of buildings are the vulnerability factors that cause a greater variability in ISEVI scores. The method deployed here may allow specific strategies for vulnerability reduction to be developed based on disaggregating the validated ISEVI into dimensions and components and using the regional spatial patterns characterized.
... CONNECTION TO NATURE: Biophilia: Connection to all of life (1) [37] CULTURAL FULFILLMENT: Cultural Activity: Performing arts attendance (1) [38]; Belonging to religious denomination (1) [37] EDUCATION: Basic Skills of Youth: Standard math test achievement (2) [39]; Standard reading test achievement (2) [39]; Standard science test achievement (2) [39] Participation/Attainment: Adult illiteracy rate (3) [40]; High school graduation rate (14) [32]; Post-secondary education enrollment (14) [32]; Post-secondary education graduation (14) [32] Social Aspects: Children feeling unsafe at school (5) [41]; Children's health (4) [42]; Children's social behavior (5) [41] HEALTH: Care: Regular doctor visits (17) [43]; Satisfaction with hospital care (2) [43] Life Expectancy/Mortality: Asthma mortality rate (16) [44]; Cancer mortality rate (16) [44]; Diabetes mortality rate (16) [44]; Heart disease mortality rate (16) [44]; Infant mortality rate (18) [44]; Life expectancy at birth (18) [45]; Suicide mortality rate (16) [44] Personal Well-Being: Happiness (1) [37]; Life satisfaction (6) [43]; Perceived health (18) [43] Lifestyle/Behavior: Alcoholic beverage consumption (17) [43]; Healthy Behaviors Index (9) [43]; Teen pregnancy rate (18) [43]; Teen smoking rate (4) [41] Physical/Mental Conditions: Lifetime adult asthma rate (18) [43]; Lifetime adult cancer rate (8) [43]; Lifetime child asthma rate (13) [43]; Lifetime adult depression rate (9) [43]; Lifetime adult diabetes rate (18) [43]; Lifetime adult heart attack rate (14) [43]; Lifetime adult heart disease rate (14) [43]; Adult obesity rate (18) [43]; Lifetime adult stroke rate (14) [43] LEISURE TIME: Leisure Activity: Physical activity participation (18) [43]; Time spent on vacation (10) [46] Time Spent: Time spent on leisure or relaxing (1) [47] Working Age Adults: Percent working long work hours (12) [48]; Percent daytime work hours (12) [48] LIVING STANDARDS: Basic Necessities: Food security (1) [49]; Home ownership cost/income ratio (13) [32] Income: Median household income (13) [32]; Poverty rate (13) [32]; Persistent poverty rate (11) [32] Wealth: Median home value (13) [32]; Mortgage debt (13) [32] Work: No fear of job loss (13) [50]; Job satisfaction (1) [51] SAFETY/SECURITY: Actual Safety: Accidental death rate (16) [44]; Natural event injury/death rate (15) [52]; Millions of dollars in natural event damage (17) [52]; Property crime rate (17) [53]; Violent crime rate (17) [53] Perceived Safety: Perceived safety (1) [54] Risk: Social Vulnerability Index (1) [55] SOCIAL COHESION: Attitude Toward Community: Trust in people (1) [37]; City satisfaction (6) [56]; Feeling close to one's town or city (1) [57]; Perception that others are helpful (1) [37] Democratic Engagement: Interest in politics (1) [37]; Registered voters (4) [58]; Satisfaction with democracy (1) [37]; Trust in government (1) [37]; Voice in government (1) [37]; Voter turnout (4) [58] ...
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... Sensitivity analysis assesses the contribution of the individual source of uncertainty to the output variance. While uncertainty analysis is used more often than sensitivity analysis and is almost always treated separately, the iterative use of uncertainty and sensitivity analysis during the development of a composite indicator could improve its structure (Saisana et al., 2005a;Tarantola et al., 2000;Gall, 2007). Ideally, all potential sources of uncertainty should be addressed: selection of individual indicators, data quality, normalisation, weighting, aggregation method, etc. ...
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Social science research on disasters began in the early twentieth century with the publication of Samuel Henry Prince's sociology doctoral dissertation on the 1917 Halifax explosion (Prince 1920). However, disaster research did not begin to coalesce as a field until pioneering research was carried out by the National Academy of Sciences and the National Opinion Research Center in the early 1950s, as research teams were sent into the field to collect data on individual, group, and organizational responses to disasters (see Fritz and Marks 1954). The Disaster Research Center, established in 1963 at the Ohio State University and now located at the University of Delaware, continued the practice of conducting "quick-response" studies following major disasters, with an emphasis on organizational and community response. Over subsequent decades, other research centers were established both nationally and internationally. The terrorist attacks of September 11, 2001 generated additional interest in disaster research, as questions were raised concerning a range of topics, including behavioral, psychological, and social-psychological responses to terrorism. Classic sociological research on disasters emphasized the pro-social and adaptive dimensions of disaster-related behavior. Studies consistently documented such patterns as widespread helping behavior among community residents, the emergence of new groups focusing on victim and community needs, increases in social cohesion, the convergence of volunteers and material resources into disaster areas, and the suspension of community conflicts as community residents and public and private-sector organizations put aside their pre-disaster agendas in the interest of overcoming disaster-induced challenges. Disasters were framed in the literature as "consensus" crises and contrasted with "conflict" crises such as riots. Outcomes following disasters include the emergence of "therapeutic communities" that support victims and maintain high community morale. Therapeutic communities help to cushion the negative psychological consequences of disasters, and as a result, negative psycho-social reactions tend to be short-lived following disasters (see Fritz 1961; Barton 1969; Dynes 1970; Stallings and Quarantelli 1985; Drabek 1986). Ongoing research on disasters provides additional support for these earlier empirical findings. At the same time, it has become increasingly evident that earlier consensus-oriented perspectives paid insufficient attention to the diverse ways in which individuals, groups, and communities experience disasters. In contrast with classic studies, newer research has emphasized those diverse experiences. Research has also shown how disaster-related experiences are shaped in important ways by the same dimensions of stratification and inequality that influence people's lives during non-disaster times. Disaster scholarship now recognizes that factors such as wealth and poverty, race and ethnicity, gender and age influence vulnerability to hazards, disaster victimization, and disaster recovery outcomes (Blaikie et al. 1994; Peacock, Morrow, and Gladwin 1997; Bolin and Stanford 1998; Fothergill 1998). As a consequence of these developments, disasters are no longer seen as producing common or typical challenges for at-risk populations. While morale and cohesiveness may undoubtedly be high within some groups within a disaster-stricken community, other groups may be excluded. Postdisaster experiences that are therapeutic for some may be corrosive for others. Some groups may be able to return to their pre-disaster status with relatively difficulty, while others may never fully recover. And to a greater degree than has been recognized before, disasters may become arenas not only for consensus-based social action but also for contentious intergroup interactions. Measures taken to deal with disasters may be welcomed by some groups but denounced by others. Relief programs may benefit some within the population while disadvantaging others Research also shows that groups are differentially vulnerable and also differentially resilient in the face of disasters, depending upon their position in the stratification system. The sections that follow discuss recent advances in the study of the social factors that affect disaster vulnerability and that contribute to resilience in the face of disasters. Using examples from both Hurricane Katrina and other U.S. disasters, these discussions illustrate how large-scale social trends, structural forces, and group characteristics influence preparedness for, responses to, and recovery from disasters. A key point made in these discussions is that while Hurricane Katrina revealed the devastating consequences of social inequality more vividly than any recent U.S. disaster, Katrina has a great deal in common with other disasters the nation has experienced. One implication of these findings is that diverse patterns of vulnerability and resilience must be taken into consideration both in programs that provide disaster aid and in overall planning frameworks for disaster loss reduction. Copyright