Disaster resilient societies

Journal of Homeland Security andEmergency Management

Volume5, Issue1 2008 Article 2

Review ofMeasuring Vulnerability to NaturalHazards: Towards Disaster Resilient Societies

Lucien G. Canton∗

∗Lucien G. Canton, CEM (LLC), [email protected]

Copyright c©2008 The Berkeley Electronic Press. All rights reserved.

Review ofMeasuring Vulnerability to NaturalHazards: Towards Disaster Resilient Societies

Lucien G. Canton

Abstract

Review ofMeasuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies.Reviewed by Lucien G. Canton, CEM, Emergency Management Consultant, Lucien G. Canton,CEM (LLC), San Francisco CA.

Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies. Jörn Birkmann, Editor. United Nations University Press, 2006.United Nations University, Tokyo, Japan. 524 pages. ISBN 92-808-1135-5 Review by Lucien G. Canton, CEM, Emergency Management Consultant, Lucien G. Canton, CEM (LLC), San Francisco CA.

The starting point for emergency management is an understanding of risk. Risk assessment forms the basis for hazard reduction and capacity building. The crucial element in understanding the risks facing a community is identifying the vulnerability of the community to hazards. It is something of a shock then to realize that, not only is there no single method for assessing vulnerability, but there is not even agreement on basic terms, such as risk and vulnerability. This problem is just one of the many issues that Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies brings into sharp focus as it considers the current state of vulnerability assessment. Edited by Jörn Birkmann, Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies uses the work of experts from across the globe to discuss the issues surrounding the measurement of vulnerability at both the micro and macro levels. The authors consider problems in defining vulnerability, the use of indicators, existing methodologies and their shortcomings, and directions for future research. International in scope and academic in tone, Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies is a welcome addition to any professional library. Organization The book is organized into five sections, each focusing on a specific area related to measuring vulnerability. Part I examines the theories and principles related to measuring vulnerability. In the initial chapter, Jörn Birkmann highlights the problems involved in measuring vulnerability by discussing the lack of generally accepted definitions of risk. More importantly, he argues persuasively for a paradigm shift from hazard analysis to vulnerability assessment as a necessary step to developing programs that actually reduce risk. The remaining chapters build on this theme by considering the nature of vulnerability and the potential indicators and corresponding proxy data that could be used to measure it. Part II considers the impact of environment on vulnerability and discusses the use of vulnerability assessment models in relation to long-term climate change and other environmental events. Part III, however, is the true heart of the book. An initial chapter by Mark Pelling provides an overview of global risk index

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projects and is followed by detailed chapters on the Disaster Risk Index, Disaster Risk Hotspots project, and the Americas Indexing Program. Two additional chapters consider a multi-risk model based on existing European databases and a field study in Tanzania to measure vulnerability. The section concludes with a chapter by Erich Plate that offers an intriguing new concept for setting priorities on the basis of a Human Security Index. While Part III is concerned with aggregating information at the global or national level, Part IV considers the measurement of vulnerability from a local perspective, in essence moving from the quantitative to the qualitative. The five chapters primarily report on various studies focused on small communities. Juan Carlos Villagrán de León offers a new perspective by suggesting the measurement of vulnerability by sector as a means shifting responsibility for risk reduction from the central government to the appropriate sector. Part V considers the measurement of the capacity of institutions to cope with disaster. The authors consider both the thorny issue of defining coping capacity and the difficulties in measuring it. They also consider methodologies for increasing coping capacity through lessons learned from previous disasters. An unlooked-for gem is the last chapter by Katharina Thywissen, in which she attempts to create a core terminology by developing a comparative glossary. Her work, like a similar project by Dr. Wayne Blanchard at FEMA, allows the reader to consider multiple definitions for a term along with the original source or sources of that definition. Key Concepts A number of recurring themes can be found in Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies. One of the most critical is the need to define terms. Even among a group that is as cohesive as the authors of the various chapters in this book, there are still differences when they discuss the definitions and inter-relationships of concepts, such as risk, vulnerability, hazard, exposure, resilience, and coping capacity. A number of authors present models that, while similar, do have some differences, supporting Birkmann’s point that there is no single, generally accepted model for defining risk. The reason for this disparity in definition is eloquently illustrated throughout the book: vulnerability is a complex issue. One can measure vulnerability as exposure to hazards or as potential loss to gross domestic product. One can also consider the vulnerability of individuals, communities, or institutions. Vulnerability can be divided by geographical region or by sector. There are also inter-relationships and hazard nesting (a situation where one hazard generates another, such as mudslides resulting from flooding). Consequently,

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there can be no single definition of vulnerability without consideration of the context in which the examination is taking place. This issue of defining terms is important when one approaches methodologies for measuring vulnerability. Vulnerability is measured through the use of indicators that can be a single variable or an aggregate of data and may include both quantitative and qualitative measures. Birkmann discusses the use and importance of indicators and suggests criteria for the selection of indicators in Chapter 2. In Chapter 3, Schneiderbauer and Ehrlich further refine this analysis as it applies to social levels. Taken together, the chapters support the need to define vulnerability as a prerequisite for selecting indicators. In addition to issues related to definition, indicators also create their own set of problems as noted by Mark Pelling in Chapter 7. In his summary of the three models in the following chapters (Disaster Risk Index, Disaster Risk Hotspots and the Americas Indexing Program), Pelling notes that one can approach the measurement of vulnerability through deduction by examining past losses (DRI and Hotspots); or one can use an inductive approach by measuring potential losses (Americas Indexing Program). Both approaches have advantages and disadvantages. The deductive approach is grounded in actual hazard experience, but is heavily reliant on that experience. This reliance on past events means that the deductive approach cannot be used to predict future risk distributions. The inductive approach offers the advantage of being a predictive model, but, depending on the selection of the variables, may be subject to political manipulation. Pelling’s study of the three models also considers related issues, such as the overlap of data. He also points out problems with the use of economic data or the use of impact on gross domestic product (GDP), particularly in the deductive approach. Such measures may lack any information on long-range impacts or may mask losses to the informal sector. In considering data, there is also an issue of hazard-specific versus hazard-independent focus. A hazard-specific focus relies on data from a specific type of event. For example, Lebel and his colleagues consider the assessment of coping capacity in relation to floods in Chapter 19. By contrast, Greiving in Chapter 11 considers multiple hazards in Europe in developing his model for vulnerability assessment. Again, there are problems and advantages to both methods. One of the strengths of the book is that the authors do not present any model as being superior to the rest; they report their results and allow the reader to draw conclusions. Availability of data is a common problem encountered in all the models considered throughout the book. For each indicator, researchers identify proxy data based on their definition of vulnerability. However, data are frequently unavailable or incomplete. This gives rise to concerns that indices only



approximate vulnerability and are not as precise or as objective as one may be led to believe. This is supported by Pelling’s contention that a multi-hazard approach is essential in measuring vulnerability and suggests that no single measure is appropriate in all circumstances. The ultimate use of any measurement of vulnerability is to assist in hazard reduction. While the use of indices is effective on a national level, de-aggregating data may not help much in determining effective hazard reduction at local levels. For this, one must use a more qualitative approach. In practice, this usually means the development of carefully crafted questionnaires that can be used either to provide a self-assessment or as an interview tool by researchers. Bollin and Ria Hidajat describe the use of a questionnaire in Indonesia to develop a community-based risk index, translating qualitative responses into a quantitative model. Wisner in Chapter 17 describes the use of a self-assessment questionnaire to engage communities in hazard reduction. In Chapter 16, Villagrán de León suggests an interesting public policy approach by measuring vulnerability by sector. His contention is that, by categorizing vulnerability by sector, one can transfer institutional responsibility for hazard reduction from national disaster management agencies to the applicable sector. He argues that ultimately the institutions in charge of the sector reduce vulnerability and that categorizing vulnerability by sector can help these institutions to recognize and accept responsibility for vulnerability reduction. Vulnerability is also a function of the ability of institutions to cope with the effects of hazards. However, coping capacity is one of the most difficult variables to assess, as it is both difficult to quantify and subject to political manipulation. Cardona proposes a Risk Management Index in the Americas Indexing Program (Chapter 10), based on an institutional commitment to risk identification, risk reduction, disaster management, and financial protection. In Chapter 21, Billing and Madengruber adapt the Disaster Risk Index outlined by Peduzzi in Chapter 8 to produce a composite disaster risk index to measure coping capacities among countries. In the end, however, these quantitative approaches, in the absence of any standards for disaster risk management, cannot truly capture the largely qualitative essence of coping capacity. One component of coping capacity is the financial ability of institutions to deal with crisis. The search for a method of measuring economic vulnerability is hampered by the lack of data demonstrating the true cost of disasters in terms of both economic loss to the informal sector and of long-term costs and impacts. Cardona approaches economic vulnerability through a Disaster Deficit Index, based on the ratio of economic loss to economic resilience. Mechler and associates in Chapter 20 consider the issue of financial vulnerability in developing countries through the use International Institute for Applied Systems Analysis Catastrophic Simulation (CATSIM) model. However, he warns that in both the



CATSIM model and Cardona’s indices, data may be missing or distorted and that results should be viewed very carefully. Future Directions After reading Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies one could view the current state of vulnerability assessment as bleak. There are no agreed upon definitions and no standard assessment models. The models that exist rely on data that is unavailable or incomplete. Yet this would be a very distorted view. The disagreements on definitions are ones of degree; researchers actually agree more than they disagree. It is appropriate that some terms be defined in the context within which they operate. While there is a need to use results carefully, the models that exist represent a quantum leap forward for national disaster management agencies, particularly the work of Cardona. Birkmann does an admirable job of summing up future directions in Chapter 23. Among his conclusions are:

• The use of quantitative versus qualitative measures depends on the level of assessment. Quantitative methods may be more appropriate for identifying national vulnerabilities, while a qualitative approach may be more useful at the sub-national or community level.

• Hazard-specific and hazard-independent approaches to the measurement of vulnerability each consider different aspects of vulnerability and use different indicators. Future research should consider how to combine both approaches to cover the full range of vulnerability.

• While global indexing has some utility, the use of indices may be too vague to adequately describe how changing socio-economic and environmental factors affect vulnerability. These projects need planning and decision-making.

• Estimating economic vulnerability is a compromise between reliable economic data based on past events and forecasted data based on assumptions for the future. While there is a need to for grounding in existing historical data, the shortcomings of that data need to be better understood, and economic vulnerability estimation should include a forecasting component.

• Vulnerability measurement is complex, despite attempts to simplify it through the use of models. It is unlikely that there will ever be a single accepted set of indicators or a single agreed-upon model. However, significant progress could be made if it were possible to develop common terminology for key components of vulnerability.



• Research into methods for vulnerability assessment would benefit from more clearly defined goals and standards. These goals should help bridge the gap between the theoretical and political decision-making.

Conclusion Measuring Vulnerability to Natural Hazards: Towards Disaster Resilient Societies is an excellent summary of current research in the measurement of vulnerability. In addition to the overall quality of the papers, Birkmann does an excellent job of framing the discussion in his introductory and concluding chapters. His analysis of current issues and future direction is particularly noteworthy and serves to bring the book into focus. The only minor quibble with the book is that it is an academic book, written by academics for academics. As such, it can be rough going for the layperson. This is unfortunate, as the politicians and emergency managers who would most benefit from the information presented in the book will most likely never read it. This is a loss, as this book has much to say about the nature of disaster and potential policy implications and is well worth reading.



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Disaster resilient societies