Dávid Karácsonyi Andrew Taylor Deanne Bird Editors

# The Demography of Disasters

Impacts for Population and Place

The Demography of Disasters

Dávid Karácsonyi • Andrew Taylor • Deanne Bird Editors

## The Demography of Disasters

Impacts for Population and Place

Editors Dávid Karácsonyi Geographical Institute, Research Centre for Astronomy and Earth Sciences Hungarian Academy of Sciences Budapest, Hungary

Deanne Bird Faculty of Life and Environmental Sciences, Askja University of Iceland Reykjavik, Iceland

Andrew Taylor Northern Institute Charles Darwin University Darwin, NT, Australia

#### ISBN 978-3-030-49919-8 ISBN 978-3-030-49920-4 (eBook) https://doi.org/10.1007/978-3-030-49920-4

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### Foreword

It is my honor to introduce the present book titled The Demography of Disasters, Impacts for Population and Place to the reader. While the title suggests a social science inquiry on disasters from the angle of demography, the subtitle of the book clearly reflects that the geographer's perspective is inevitable when analyzing disasters. Geography plays an important role in understanding complex interactions of human–earth systems. Geography also bears the potential to help and coordinate policy-making, addressing the challenges of growing entropy in our technological society. These advantages of geography come from the holistic understanding of the world which enables geographers to see the disaster in a spatial perspective. That perspective is particularly helpful in addressing issues of global climate change.

The climate emergency impacts Australia immensely, as it is facing longer and more intensive bushfire seasons. Nevertheless, climate change recently affects less disaster-prone nations, such as Hungary as well. Landslides, floods, extreme rainfalls along with desertification in certain areas of Hungary constitute a major hazard risk affecting the livelihood of several thousand people. We have experienced over a long period of time the floods of the Tisza river, the second major waterway of Hungary after the Danube. The floods damaged entire villages or even sometimes cities located on the floodplains, altering the regional prospects of Alföld (The Great Hungarian Plain). Engineering design failures and poor technical maintenance often interplay with extreme rainfall, making the casualties even more serious. This was the case in 2010, when the Ajka alumina plant reservoir accident happened, which was the most significant technological disaster in the recent history of Hungary. The disaster caused a red mud spill, killed ten people, injured hundreds, and contaminated significant area with the caustic substance. The Hungarian Academy of Sciences and in particular the Geographical Institute played an important role in investigating these disasters and providing mitigation strategies, which explains our interest in a broader international cooperation of disaster studies.

The volume you have in your hands is the first result deriving from that cooperation between the Geographical Institute of the Research Centre for Astronomy and Earth Sciences (Hungary) and the Northern Institute of Charles Darwin University. A large international team came together to present this book including scholars from Asia-Pacific, the USA, and the post-Soviet countries providing a broad spectrum of understandings on disasters. The thirteen chapters of the book range from theoretical studies on demography of disasters to discussions of technological accidents such as Chernobyl. The present volume includes two chapters on the 2011 Tohoku earthquake considered the most significant disaster impacting Japan since World War II. Hurricane Katrina in 2005, bush and forest fires in California and in Russia, heat waves in Australia are also discussed in the book, each of which directly can be linked to climate change.

Each author has demonstrated their commitment to this unique and valuable book project for better understanding the disaster–demography interaction. I would like to acknowledge in particular the role Andrew Taylor played in this project. From the very beginning, he invested tremendous energy arranging the academic cooperation between our institutions, securing financial resources and managing the preparation of the manuscripts. I sincerely look forward to the future prospects in the disaster–demography study field in which the present volume will probably be considered as a significant step forward.

> Dr. Károly Kocsis Academician Director of the Geographical Institute Research Centre for Astronomy and Earth Sciences Hungarian Academy of Sciences Budapest, Hungary

### Preface and Acknowledgements

The present book is the result of a collaboration between the Geographical Institute of the Research Centre for Astronomy and Earth Sciences, Hungary, the Northern Institute of Charles Darwin University, Australia, and the Faculty of Life and Environmental Sciences, University of Iceland. The book was first proposed some time ago by fellow editor Andrew Taylor when we discussed demographic issues around disasters following a seminar talk I gave during my first visit to Darwin. Since then Andrew has put a lot of energy and enthusiasm into making this book happen. Along with his contributions as editor and author, he also generously supported the cooperation between our institutions, particularly my visit to Darwin when we reviewed and discussed the chapter manuscripts provided by authors from various backgrounds. In the meantime, Deanne Bird, who is currently commuting between Reykjavík and Melbourne with responsibilities in disaster mitigation, also joined our editorial team and helped us with her experience in the disaster study field and in negotiating with Springer, the publisher of this volume. She also helped to get additional authors on board and with reviewing their submissions.

This book discusses a new and broadening field which links demography and disaster studies. Traditionally, people have viewed disasters as shocks to everyday routines, the result of an unanticipated natural hazard event or as engineering failures and therefore the domain of technological rather than social sciences. Under these paradigms, the links between disasters and demography seem relatively simplistic and unidirectional, with the focus on estimating post-disaster populations, measuring mortality or understanding out-migration impacts. Nevertheless, disasters have the capacity to fundamentally alter population profiles at local and regional levels. Impacts vary according to the type, rapidity, and magnitude of the disaster, but also according to the pre-existing population profile and its relationships to the economy and society. In all cases, the key to understanding impacts and avoiding them in the future is to understand the relationships between disasters and population change, both prior to and after a disaster.

The aim of this book is to provide a comprehensive discussion on the demography of vulnerability and resilience in the face of disasters, the demography of risk from disaster impacts for vulnerable groups. Demographic methods can help in post-disaster population estimation and in managing and mapping people. In many cases, human migration is a common response to disaster, and hence, there is a link to spatial population dynamics as well. The demography of policy and practice around disaster mitigation is also an important part of the present volume along with profiling future risks and opportunities. The demography of climate change highlights the disaster–demography link in a specific way. In line with the multifarious nature of the disaster–demography nexus, our book takes an interdisciplinary approach, with chapters ranging from geography to gendered understanding of disaster resilience.

The Demography of Disasters seeks to advance both practical and theoretical insights into our understanding of the role of demography in planning for and mitigating impacts from disasters in developed nations. We hope that the book will provide policy-makers, disaster recovery experts, planners, and academics in the field with a wide range of examples demonstrating the importance of the interplay between demography and disasters in regions and spatially. This book will be of interest to social scientists across a range of fields. The book is also helpful for policy-makers, planners, practitioners of disaster management, and environmental agencies who are interested in a demographer's perspective on disaster. Academics and students in areas such as demography, disaster management, climate change, social policy, and human studies are also the targeted audience.

Most of the contributors to this book have come from academia, spanning a broad range of countries, including but not limited to Japan, Germany, USA, Sweden, Ukraine, and Russia. It has at times been a difficult task to coordinate such a broad and diverse team with different perspectives and scientific backgrounds. It is the editors' hope that through this book project, the team of authors will become part of an academic community which will in the future further contribute to our understanding of the disaster–demography nexus.

The editors have taken the view that human geography is closely related to the disaster–demography nexus, and hence, we have made extensive use of maps, the most common communication language of geographical science. Special attention has been paid to presenting a uniform cartographic design and layout throughout the book which I hope will make this volume more visually appealing to the reader.

I would like to acknowledge here the tremendous help given by Shelly (Shell) Worthington who assisted us tirelessly in proofreading and editing all the chapter manuscripts. Special thanks also go to Ferenc Probáld, Professor Emeritus of Eötvös Loránd University (Budapest, Hungary), my former Ph.D. supervisor, who was always ready to check and comment on my work. Also many thanks to Kang-tsung (Karl) Chang for his rigorous but helpful review comments, along with all the other reviewers of each chapter including Tony Barnes, Sigurd Dyrting, Kat Haynes, Richie Howitt, Anita Maertens, Jane Mullet, and Jan Salmon. This project would not have been possible without the support of Károly Kocsis, Director of the Geographical Institute in Budapest, and László Kiss, General Director of the Research Centre for Astronomy and Earth Sciences who also arranged funding from the Hungarian Academy of Sciences to cover some of the costs related to the present volume. Thanks also go to the Japan Society for the Promotion of Science (JSPS) for the one year I spent at the International Research Institute of Disaster Science at Tohoku University in Japan which helped me greatly in gaining a better understanding of disaster science as a distinguished academic field.

I hope you enjoy reading this book on the various perspectives of the disaster– demography nexus. There are inevitably more approaches than what we were able to include in the following chapters some of which raise more questions than answers. However, I believe the collaborations featured in this project will push further the discussion on the demography of disasters.

Darwin, Australia January 2020

Dávid Karácsonyi

### Contents

### Editors and Contributors

### About the Editors

Dávid Karácsonyi has been working at the Geographical Institute of Hungarian Academy of Sciences (Budapest) since 2009 where he is currently a research fellow. He is a geographer, specialized on human and regional geography. Dávid is interested in the geography of peripheral and rural areas and has conducted his research in Ukraine and Belarus, studying rural spaces and their populations. Recently, he has spent two and half years in East Asia first at the International Research Institute of Disaster Science, Tohoku University, Japan, where he compared the impacts of disasters like Chernobyl and Fukushima on regional population trends, than at the Department of Geography, National Taiwan University. Currently, he is also a research associate at the Northern Institute of Charles Darwin University.

Andrew Taylor Northern Institute, Charles Darwin University, Darwin, Australia. Andrew researches the causes and consequences of population change for the Northern Territory of Australia and northern regions more broadly. He undertakes both quantitative and qualitative researches to understand impacts from policy, economic, and structural changes for communities. In his Ph.D., he investigated policy and theoretical implications from changing migration practices for Indigenous Territorians. Prior to academia, Andrew worked for a decade with the Australian Bureau of Statistics.

Deanne Bird is Research Specialist at the Faculty of Life and Environmental Sciences, University of Iceland. She specializes in evaluating societal resilience and vulnerability in relation to emergency preparedness, response, and recovery. Deanne has collaborated on a variety of projects with community groups and, government and non-government organizations and is Associate of Monash University Disaster Resilience Initiative, Monash University. Deanne also works as Senior Advisor—Engagement for the Victorian Department of Health and Human Services within the Latrobe Health Innovation Zone. As Senior Advisor, Deanne is responsible for local project leadership, coordination, monitoring, and reporting relating to specific actions arising from the 2014 Hazelwood Mine Fire. Through her position at the University of Iceland, and as an editor of Demography of Disasters, Deanne is supported by the Nordic Centre of Excellence for Resilience and Societal Security—NORDESS, which is funded under the Nordic Societal Security Programme.

### Contributors

Per Axelsson is Associate Professor at the Department of Historical, Philosophical and Religious Studies and affiliated researcher at the Centre for Demographic and Ageing Research and the Centre for Sami Research (Vaartoe) at Umeå University. Per publishes widely on the demography and health of Sami people in the eighteenth and nineteenth centuries. He has a particular interest in improving sources of data about Sami health and demography, and has undertaken comparative studies in Australia, New Zealand, and Canada among other places.

Jessica L. Barnes PLA, ASLA, graduated from the Disaster Resilience Leadership Academy at Tulane University in New Orleans in 2018. She is now the founder and principal at Third Coast Collaborative, a US-based landscape architecture firm dedicated to promoting community resilience and inclusive access to public spaces through design.

Doris A. Carson is an economic and human geographer interested in the socioeconomic development of communities in sparsely populated, rural, and remote areas. She completed her Ph.D. in 2011 at James Cook University in Australia, looking at the dynamics of regional tourism innovation systems in remote resource peripheries. Doris also holds a Master degree in tourism and leisure management from the IMC Krems University of Applied Sciences in Austria. Doris moved to Umeå in northern Sweden in 2014 to work on tourism and lifestyle-related mobilities in the Arctic and their impacts on innovation capacity in small rural communities. She is now a researcher and lecturer at the Department of Geography and Economic History at Umeå University, specializing in tourism, lifestyle mobilities and migration, and small community development in sparsely populated areas.

Dean B. Carson has spent the past 20 years researching who lives in, works in, and visits sparsely populated areas, and how and why these patterns change over time. Dean has worked in Australia, Canada, Scotland, Australia, and Sweden. He is currently the inaugural Visiting Professor at the Arctic Research Centre at Umeå University (Arcum) and Guest Professor with Sweden's Centre for Rural Medicine. His primary research interest is demographic change in small towns and villages.

Serhii Cholii is an associate professor (docent) at the chair of history, Igor Sikorsky Kyiv Polytechnic Institute. He is a historian, investigating the processes of implementation of different military strategies in Europe during the period of European Modernity and evolution of civil–military relations. Serhii is also interested in processes of forced migration during the nineteenth and twentieth centuries. During last years, he conducted field trips and interviews in different locations of European Polesia, studying the case of population relocation as an aftermath of Chernobyl power plant disaster in 1986.

Stephen T. Garnett is Professor of Conservation and Sustainable Livelihoods at the Research Institute for the Environment and Livelihoods, Charles Darwin University. Much of his research has been on threatened species, particularly birds, but he has studied and written on a wide variety of environmental issues. He is particularly interested in the synergies arising from combining biodiversity conservation and natural resource-based livelihoods, particularly Indigenous livelihoods.

Yetta Gurtner is a human geographer, lecturer, and researcher at James Cook University, Townsville. With a multidisciplinary background in Southeast Asian Studies, her core research interests include integrated disaster management, tourism crisis management, and planning for sustainable development/disaster risk reduction. Related research interests include social impact assessment and an appreciation of dynamic contexts of vulnerability, capacity, adaptation, mitigation, and resilience, particularly within developing nations.

Kazumasa Hanaoka is an associate professor at Department of Geography, Ritsumeikan University, Japan. He has been a deputy director of the Institute of Disaster Mitigation for Urban Cultural Heritage, Ritsumeikan University since 2018. From 2012 to 2016, he was an assistant professor at the International Research Institute of Disaster Science, Tohoku University, Japan. His main research areas are human geography and geographic information science, in particular spatial analysis using big data. His research activities cover a number of topics related to spatial microsimulation modeling, spatio-temporal analysis using mobile phone data, census data analysis on foreign population in Japan, and population decline and recovery after a large-scale natural disaster. Also, he has numerous experiences in fieldwork research in Japan, Philippines, Bangladesh, Belarus, and Ukraine.

David King is an Associate Professor of Geography in the College of Science and Engineering at James Cook University, and is director of the Centre for Disaster Studies, and the Centre for Tropical Urban and Regional Planning. He is a Fellow of the Planning Institute of Australia. He has taught and researched at James Cook University for 28 years and was formerly at the University of Papua New Guinea for ten years. He began his career as a school teacher on the diamond fields of Sierra Leone, turning that experience into a doctorate on the social impact of the diamond rush. His research specializes in social impact and evaluation in such areas as planning, natural hazard vulnerability, climate change adaptation and resilience, disaster mitigation and recovery, as well as the social impact of mining projects, development projects, and census analysis.

Michimasa Matsumoto International Research Institute of Disaster Science (IRIDeS), Tohoku University, Sendai, Japan

Osamu Murao is a professor at the International Research Institute of Disaster Science (IRIDeS) at Tohoku University, which was established in order to disseminate learning from the 2011 East Japan Earthquake and Tsunami Disaster, and the founder of the International Strategy for Disaster Mitigation Laboratory (ISDM). His current researches focus on post-disaster recovery process and urban design, and the relationship between physical environment (architecture and urban design) and disaster. To date, with research grants, he has investigated the post-disaster recovery process for damaged areas in Taiwan, Turkey, Sri Lanka, Thailand, Indonesia, Peru, Philippines, and World Trade Center in New York. Particularly he kept tracking the recovery process of Chi-Chi Township since the 1999 Chi-Chi earthquake in Taiwan as a visiting researcher of National Taiwan University in 2005. Dr. Murao has been involved in some research projects about post-disaster urban recovery and disaster risk reduction in the world.

Tatiana Nefedova is a chief researcher, Institute of Geography, Russian Academy of Science. Tatiana is interested in spatial organization and problems of agriculture and rural areas, interaction between the cities and countryside, Russia's suburbs and dacha suburbanization, social and economic problems of Russia's regions.

Tetsuya Okada is a Ph.D. graduate, who studied human geography at Macquarie University, Australia. His Ph.D. research project investigated community development through disaster recovery in four case study areas in Australia and Japan to better understand the sociocultural, economic, and political factors of and impacts on the local sociality. He has worked on various research projects including reports on disaster recovery for the National Climate Change Adaptation Research Facility (NCCARF), the impacts of flash flooding for the New South Wales State Emergency Service in Australia, along with other academic publications. In addition, Tetsuya is also a certified professional translator in Australia and has translated a number of technical writings on a wide range of natural hazards and associated disasters between English and Japanese.

Carmen Richerzhagen is a Senior Researcher at the German Development Institute in Bonn, Germany. She is an agricultural and environmental economist with the research focus on climate and biodiversity policies and ecosystem-based adaptation.

Ethan Sharygin Demographic Research Unit, California Department of Finance, USA. Ethan is research manager with the Demographic Research Unit at the State of California Department of Finance. His research focuses on modeling fertility, mortality, and migration rates, and other topics related to housing and population estimates and projections. Prior to joining the State of California, Ethan was a postdoctoral fellow with the all-cause mortality team at the University of Washington Institute for Health Metrics and Evaluation (IHME). His previous studies involved marriage markets, imbalanced sex ratios at birth, and demographic consequences of famine. Ethan holds a Ph.D. in demography from the University of Pennsylvania.

Emma A. Singh Risk Frontiers, Department of Environmental Sciences, Macquarie University, New South Wales, Australia

Gabriella Sköld was Coordinator of the Arctic Research Centre at Umeå University (Arcum). She completed her Ph.D. at Umeå University in 2010, investigating fertility patterns among Sami populations in northern Sweden in the nineteenth century. Since then she has worked as a postdoctoral research fellow at the Centre for Sami Research (Vaartoe) at Umeå University, and has examined patterns of demographic change linked to hydro-power developments in the north of Sweden in the mid-twentieth century.

Peter Sköld is Director of the Arctic Research Centre at Umeå University (Arcum). Peter is an historian who has focused on researching the history of the Sami people of northern Sweden. His Ph.D. looked at the impact of smallpox on Sami populations during the Swedish colonization period. Peter has previously been the Director of the Centre for Sami Research (Vaartoe) at Umeå University and has served in a number of academic and political leadership positions in the Arctic and the Barents Region, including as Chair of the International Association of Arctic Social Scientists.

Yelizaveta Skryzhevska is an associate professor of Geography at Miami University of Ohio, USA. Her areas of specialization are human geography and Geographic Information Systems. Her research interests are in the fields of regional development of the post-Soviet countries such as Ukraine and Russia, and geography education. She has published numerous articles on inequalities of regional development and disparities in distribution of rural population in Ukraine, adaptation to climate change as a tool for regional development in Russia, and geography education in the US universities. She currently serves as Associate Dean for Academic Affairs at the College of Liberal Arts and Applied Science at Miami University Regionals.

Kerstin K. Zander is an Associate Professor at the Northern Institute at Charles Darwin University. She is interested in the economics of climate change impacts and adaptation, including migration. She is a Humboldt Fellow and an Adjunct Researcher at the German Development Institute in Bonn.

### **Chapter 1 Introduction: Conceptualising the Demography of Disasters**

**Dávid Karácsonyi and Andrew Taylor**

**Abstract** Understanding and documenting intersects between disasters and human demographic change is an emerging academic field. Both the study of disasters and demographic issues are broad constructs in their own rights. While it may seem obvious to link the two, as we have in this book, disasters can impact on populations and population change in multifarious, obtuse and complex ways. Our aim in this book is to extend the nascent work to improve disaster policy and planning processes through enhancing knowledge about the demography-disaster nexus. In this chapter, we overview contemporary debates and paradigm shifts within the field of disaster studies to provide conceptual links between these and the field of demography. To conclude, we outline the topics and case studies which form the basis for individual chapters in this book.

**Keywords** Disaster-demography nexus · Hazard · Vulnerability · Social embeddedness · Non-routine event

### **1.1 Introduction**

Understanding and documenting intersects between disasters and human demographic change is an emerging scientific field. This demography-disaster nexus is growing in importance as efforts to build structured and cohesive planning to prevent and mitigate disasters grow in line with the anticipated and realised increases in extreme events (Coleman 2006; Eshghi and Larson 2008; Okuyama and Sahin 2009). According to Donner and Rodríguez (2008, p. 1090), the contemporary growth in

D. Karácsonyi (B)

Geographical Institute, CSFK Hungarian Academy of Sciences, Budaörsi út 45, Budapest 1112, Hungary

e-mail<EMAIL_ADDRESS>
A. Taylor Northern Institute, Charles Darwin University, Ellengowan Dr., Darwin, Casuarina NT 0810, Australia e-mail<EMAIL_ADDRESS>
population densities in vulnerable areas and regions, and especially mass urbanisation in developing nations, is the most important factor that has increased populationrelated hazard exposure. In addition to this, the increased frequency and intensity of extreme weather events due to climate change (Katz and Brown 1992; Easterling et al. 2000; Frich et al. 2002; Coumou and Rahmstorf 2012; Jakab et al. 2019) have already contributed and soon will more significantly contribute to increased population vulnerabilities. Furthermore, global entropy has increased through technological change (Ellul 1964) and as a result of complex and systemic issues where nuclear, chemical, biotech industries and artificial intelligence along with 'traditional' threats such as pandemic, violence, war and famine bear the potential to trigger catastrophic events (Quarantelli et al. 2007). Each of these factors have the potential to alter demographic profiles and negatively affect people's lives through disasters.

The demographic make-up of populations at the time of disaster determines who is impacted and the extent of impacts on residents and others. Improving technologies, improved warning systems, investments in disaster mitigating infrastructure and improving community preparedness and response in the face of disasters are examples of attempts to reduce disaster impacts. While a range of studies have looked at demographic impacts from individual disasters, these are generally shortterm focused and concentrated on post-event analysis and evaluation. Our aim in this chapter and generally in the book is to extend the nascent work to improve disaster policy and planning process through the growing knowledge about the demography-disaster nexus.

Both the study of disasters and demographic issues themselves are broad constructs in their own rights. While it may seem obvious to link the two, as we have in this book, disasters can impact on populations and change populations in multifarious, obtuse and complex ways. Populations may be the root cause of a localised disaster or indeed be the main 'victims'. Disasters can speed up pre-existing demographic changes or create new population profiles through immediate impacts and human reactions to such events (as we learn in Chap. 2 by Karácsonyi et al., in Chap. 5 by Carson et al. and in Chap. 7 by Bird and Taylor). Their impacts on demographic change can occur on a complex time–space continuum which may involve feedback loops. Most obvious are deaths and injuries, out-migration and the temporary relocation of residents and others from affected areas which rapidly and noticeably alter the pre-existing demographic profile of a town or region. More vulnerable cohorts (like the elderly) are often disproportionately impacted. Disasters may also affect the gendered demography of places, as discussed in Chap. 9 by Barnes. Disasters may encourage populations not immediately affected by the disaster at hand to adjust their demographic behaviours, such as around fertility or migration. Such feedback loops may be complex, unknown and unpredictable, altering not only the population profile but the economies and social fabric of towns and regions well into the future (see for example, Chap. 5 by Carson et al., Chap. 6 by King and Gurtner, or Chap. 8 by Zander et al.).

This introductory chapter discusses paradigm shifts in the field of disaster studies. This provides important theoretical context to posit our examination of the disasterdemography nexus which is the core theoretical contribution of the book. In the latter part of this chapter, we outline the structure of the book to facilitate a digestible overview for the reader.

### **1.2 Disaster Studies: From 'Acts of God' to a Distinguishable Scientific Field**

In the face of the conventional perception of disasters as 'acts of God' (Robinson 2003) that are chaotic and random situations with anarchy and panic (Quarantelli and Dynes 1972; Webb 2007), the majority of disaster experts now perceive disasters are never 'accidental' (Quarantelli et al. 2007; Lavell and Ginnetti 2013). Thus, there is a need for systematic research and analysis to enhance the potential for the prevention of disasters. Samuel Prince's doctoral thesis (Prince 1920) on the 1917 Halifax explosion1 is recognised by many as the first systematic disaster study (Drabek and McEntire 2003; Perry 2007). However, the real flourishing in disaster studies started during the early Cold War era with studies on the impact of bombings on civilian's morale in World War II (see United States Strategic Bombing Survey 1947). Many of these studies attempted to address how American communities might react to a possible nuclear war. Consequently, they had strong strategic-military origins and aims along with consummate funding provided by the armed forces (Bolin 2007; Perry 2007; Rodríguez et al. 2007). A notable step forward in the institutionalisation of civilian disaster studies was the establishment of the Disaster Research Centre at Ohio State University, the first of such schools, in 1963. The School published several synthesising works on disaster studies and played a pioneering role in developing theoretical frameworks rooted in the field of social sciences (see for example, Dynes 1970; Mileti 1975; Quarantelli 1978; Oliver-Smith 1979; Drabek 1986). This nascent adjunction between disasters and social sciences more than half a century ago was arguably the beginnings of the field we recognise today.

Although early links were evident between disaster studies and social sciences, disaster studies are multifarious and are strongly multidisciplinary by nature (Quarantelli 2006). Because of this, disaster studies are not ontologically limited to a clearly defined field (see for example the debate summarised in Perry and Quarantelli 2005). Alexander (2005, p. 24) proposed, for example, that disaster studies encompass the fields of geography, anthropology, sociology, social psychology, development studies, health sciences, geophysical sciences and engineering. Consequently, members of risk, hazard and disaster study communities with various backgrounds have often taken very different approaches which Cutter (2005) proposed made it

<sup>1</sup>A cargo ship loaded with munition exploded during the World War killing approximately 2000 people.

difficult to develop a recognisable and distinctive academic field with a universally understood inner logic and framework.

As such, the field of disaster studies is constantly emerging and reshaping. This brings many benefits. Not least, the knowledge and understanding about the risks of and impacts from disasters can be sourced and considered from a wide range of disciplines; including those reflected on here. The theoretical and applied 'stock' of knowledge is, therefore, not constrained to ontological paradigms, and its evolving nature protects disaster studies from the dangers of received wisdom which may be pervasive in singular and more focused fields. Disaster studies are, therefore, plural in a conceptual, theoretical and applied sense. While the benefits are many, this also brings challenges, as we will now discuss in relation to the debate on defining precisely what constitutes a disaster and therefore disaster studies.

### **1.3 Disaster: A Non-routine Phenomenon or Embedded in Society?**

To meaningfully consider the disaster-demography nexus, it is necessary to plot the debate and literal discussion on what constitutes a disaster. As an illustration, Dynes (1970), Rodríguez et al. (2007) and Webb (2007) stressed that disaster is understood by many as an agent for bad luck to be bought to bear on the physical environment, human system and society in general. However, disasters are now widely recognised as complex events with society and populations intricately linked to the causes and consequences of individual disasters, rather than simply as victims or passive actors.

Two seminal books have sought to address the definition of a disaster; *What is a disaster?* by Perry and Quarantelli (2005) and *At risk*, by Blaikie et al. 1994 (its newer edition is Wisner et al. 2004). In the former, most contributors emphasised that a disaster can oftentimes be understood as 'departure from normal', a 'nonroutine event', as echoed by Kreps (1989) and Drabek (1989). In Wisner's work, authors understood disasters as being embedded in the 'normal' functioning of the society and in particular rooted in social inequalities. The main criticism on this 'non-routineness' position is that, if disaster occurs when society cannot function normally under severe environmental change, then members of society are usually able to cope with everyday problems and needs when there is no external hazard stress on them (Donner and Rodríguez 2008, p. 1092).

McEntire (2013) distinguished two main schools in disaster studies, the social vulnerability school (emphasising social, political and economic structures) and the holistic school (in which disasters are seen as non-routine events, related to nonroutine social problems). In the holistic school, for example, disaster definitions can be related to the scale and speed of disasters. The scale is emphasised by Quarantelli (1998, 2006) who distinguished a catastrophe from disaster and by Bissel (2013) who distinguished an emergency, hazard, disaster and catastrophe from each other based on the size of the impacted area and population. A further element in the definitional quandary is based on the different speeds of disaster impacts (Alexander 2001; Robinson 2003; Quarantelli 2006; Bissel 2013); those slowly emerging (such as sea level rise, industrial pollution, landscape degradation—see Kertész and Kˇreˇcek 2019) and rapid onset disasters (e.g. hurricanes, earthquakes and floods).

Furthermore, in the holistic school (non-routineness perspective), the definitional debate has focused on the root causes of disasters including that they may be sudden, unexpected and unwanted events (Gencer 2013) and a result of natural or human made catastrophes (Robinson 2003). Alexander (2001) categorised disasters based on the geophysical agent, such as earthquake, volcanic eruption, desertification and soil erosion. Alexander (2001) and others, such as Kapuchu and Özerdem (2013), also stressed that natural and man-made disasters are usually very different. They highlighted that a disaster is a situation where people are confronted with a sudden and uncontrollable catastrophic change caused by natural phenomena or external human action. Hence, Kapuchu and Özerdem (2013, p. 12) pointed out that disasters induced by natural hazards can be predicted to some extent, but that it is impossible to prevent them.

In contrast to the stance on disasters by Alexander, Kapuchu and Özerdem, the majority of disaster experts (e.g. Quarantelli et al. 2007) agree that each disaster is influenced by humans and can therefore be prevented. This viewpoint stresses that human actions have the potential to reduce disaster impacts. Conversely, poor or wrong decisions can worsen the situation. In support of this, Perry (2007) bought to the fore definitional differences between the terms hazard and disaster. In his view, a disaster occurs when a hazard (an extreme physical event, such as extreme rainfall, heat wave or earthquake) intersects with the social system (vulnerable human population). In a practical sense, therefore, a landslide in a remote, uninhabited area is just a geological phenomenon if there is no injury, loss of life or property damage. It is important to emphasise that only a very small fraction of hazards lead to a disaster (Quarantelli et al. 2007) because usually there is no impact on human population (see Alexander 2001 on the 1964 Sherman debris avalanche in sparsely populated Alaska).

Robinson (2003), Wisner et al (2004) and Cutter (2005) argued that a disaster is an interplay between human–social root causes and hazard event and hence can lead to a combination of multiple events (e.g. conflict causing hunger, disease and displacement). Blaikie et al. (1994) and Wisner et al. (2004) used the 'pressure and release model' to show how disasters can occur when natural hazards affect vulnerable populations. In the model, vulnerability and natural hazards are seen as intersecting forces generating systemic pressure which are released in the form of a disaster. The pressure and release model suggests that, even if the triggering event is natural, the root causes are always society-based. This view helped shift attention to the vulnerability of human–social systems. As Cutter (2005, p. 39) stated, the question is not about a disaster but about vulnerability to environmental threats and extreme events. Cutter underlines that vulnerability is embedded in human, natural and technological systems, which are interconnected, and this interaction is of utmost importance in grasping vulnerability.

Alexander (2001) surmised that human vulnerability has often been a result of underestimating the limited degree to which technology and economic systems are able to mitigate *natural disasters*. In other words, natural hazard events have the power to exert a substantial and consistent influence on modern society (ibid. p. 3). Hence, in Alexander's perception, disasters induced by these events are in fact 'natural' disasters. Alexander's view is further supported by the recent cultural turn in disaster studies (see Webb 2007, Ekström and Kverndokk 2015). Consistent with that paradigm, there are some studies on how communities living in hazard-prone areas have been influenced through their continuous disaster experiences, including in Japan (Bajek et al. 2008; Kitagawa 2016) and the Philippines (Bankoff 2003). A cross-cultural study by Paton et al. (2010) comparing Japan and New Zealand (two disaster-prone nations) revealed some universal similarities on how hazard beliefs and social characteristics interact despite the fundamental cultural differences between the two countries.

In spite of the earth science-based criticisms by Alexander and the findings by recent cultural studies, Wisner's 'social embeddedness' view is widely accepted by disaster study experts with a sociology background. Hence, these scholars tend to avoid the use of the term 'natural disaster' (see O'Keefe et al. 1976; Cannon 1994; Cohen and Werker 2008). Despite this, the term 'natural disaster' is still common particularly in the economic, demographic and geographic literature (see for instance, UN General Assembly 1989; Cavallo and Noy 2011; Cavallo et al. 2013). Some authors have concluded that the 'natural disaster' events they studied have different impacts for developing nations (Kahn 2005; Toya and Skidmore 2007; Loayza et al. 2012; Chen et al. 2013), for women (Enarson 2000; Neumayer and Plümper 2007) or for low-income people (Masozera et al. 2007). These all emphasise that the severity of a disaster is related to social, rather than natural characteristics, in support of Wisner and his colleague's (2004) view that disasters are rooted in 'social' rather than in 'natural' causes.

Wisner et al. (2004, p. 92) went further to suggest a more 'radical' social embeddedness view, stating even nature itself can be considered as a part of the resources that are allocated by social processes, such that, under routine social functioning, people become more or less vulnerable to hazard impacts. Hence, vulnerability to natural hazards is a social construct (Lavell et al. 2012). According to Wisner, vulnerability describes a set of conditions that people derive from their historical, cultural, social, environmental, political and economic contexts, as well as socio-economic status. In Wisner's definition (ibid. p. 11), vulnerability is 'the characteristics of a person or group and their situation that influence their capacity to anticipate, cope with, resist and recover from the impact of natural hazard events'.

Wisner's assumption has been further elaborated on by Oliver-Smith (2009) who argued that "social systems generate the conditions that place people differentiated along axes of class, race, ethnic, gender or age, at different levels of risk from the same hazard and subject to different forms of suffering from the same event" (p. 120). Such perspectives were the first to mark direct links to population and their characteristics according to demographic traits such as age, race, gender and socio-economic status. Hence, vulnerable groups are not only at risk because they are exposed to a hazard but as a result of their marginality, of everyday patterns of social interaction and organisation and their constrained access to resources (Cardona et al. 2012, p. 71). Further, Wisner et al. (2004) accentuated that levels of vulnerability change during the life-course (e.g. partner formation, child bearing and later years) such that vulnerability for individuals may be temporary or in flux based on a range of factors in their lives including changes in occupation, immigration status or residence and again, the links to the field of demography become evident.

Of course, in the academic discourse, disasters are not only approached through root causes and triggering events, but also in terms of consequences. While the 'social embeddedness' approach accentuates social conditions as both the root cause and consequence from disasters, the 'non-routineness' perspective has a strong social science emphasis regarding consequences, which are understood as 'non-routine' social conditions generated by the disaster. These consequences may include significant loss of resources and threats to life (Frankenberg et al. 2014, p. 3), causing severe physical injuries, emotional distress and substantial property damage (Flanagan et al. 2011). According to Robinson (2003) and Smith (2005, p. 233), disasters change social and human life and livelihood in a negative way for certain groups hit directly or indirectly by the event, leading to serious disturbances and disruptions to the functioning of a society. In addition, Lindell (2013) summarised disaster consequences into two main groups, physical impacts (e.g. casualties, damage) and social impacts (psychological, demographic, economic and political impacts).

In summary, analysing literature in which disasters are defined, debated and understood highlights some successive paradigm shifts in disaster science (Fig. 1.1), the move away from seeing disasters as non-routine cyclic events, meaning simply a departure from, then a return to 'normal'. Even the 'normal' is often a different, deteriorated or improved situation compared to the initial stage. Hence, the disaster life cycle, a fundamental framework for disaster studies (Coetzee and Niekerk 2012; Lavell et al. 2012), which was proposed by Mileti (1975), Baird et al. (1975) and Drabek (1986, 1999), was broadly used by key institutions such as UN Office for Disaster Risk Reduction (UNISDR 2009) and Federal Emergency Management Agency (FEMA) of the USA has been criticised as being overly simplistic (see Lewis 1999). Disasters are complex, multidimensional events where root causes and consequences are embedded in the functioning of society, and they are related to policy and political management failures, social injustice and exclusion. Ultimately, this conception of disasters focuses attention on the relevance of the disaster-demography nexus in understanding, managing and recovering from disasters.

### **1.4 Method and Structure of the Book**

The book consists of eleven, mostly multiple-authored chapters which aim to compare jurisdictions and provide insights from different cases. The cases range from technological to natural hazard events and population vulnerabilities. It is important

**Fig. 1.1** Paradigm shifts in disaster studies

to highlight that several other shock events, other than natural hazards, technological accidents, infectious diseases or climate change could also unfold vulnerabilities and hence lead to disastrous demographic consequences for populations. Unrest, war and ethnic cleansing could be also understood as part of demography of disasters (see Drabek 1999; Wisner et al. 2004) along with pandemics or economic crises because they change the demographic profile of the impacted populations and lead to mass displacements. Global disasters (nuclear war, climate change) are part of the disaster literature dialect as well (see Giddings 1973), and hence, the concepts of 'risk society' or 'global risk society' have been introduced by Wisner et al. (2004) and Cutter (2005). In addition, Wisner et al. (2004) suggested disasters caused by natural hazards are not the greatest threat to humanity in comparison with violent conflicts or famines which interact with each other, making disaster impacts worse. Of course, the cases presented in this volume are limited in scope. That is why we summarised other ways of disaster-demography nexus in Chap. 13. Hence, the final chapter is not only summarising the learnings from the present volume but also serves as an extended literature review.

This volume contains significant spatial-geographical analysis, and this is the basis for its subtitle 'impacts for population and place'. For example, Chap. 2 has a strong emphasis on spatiality through permanent mass displacements. Chap. 3 and

#### 1 Introduction: Conceptualising the Demography of Disasters 9

**Fig. 1.2** Locations and triggering events of the disasters represented in this book

the comparative example in Chap. 4 draws attention to how bushfires impacted population migration in California while in Chap. 4 we learn of the contributing effects of a lack of forest maintenance to catastrophic forest fires in Russia. Geography is also represented by the spatial variation of case study areas in this book (Fig. 1.2) covering Europe, Asia, North America, Australia and New Zealand. Altogether 13 disaster cases are discussed in this volume with the majority occurring in the twenty-first century.

The following chapters aim to broaden links between demography and disasters. Chapters 2–8 focus on holistic population-disaster linkages where hazard events alter population trends (disaster-induced mass displacements, migration as heat adaptation strategy, long-term impact of disasters in sparsely populated areas) or population change generates disaster risks. Chapters 9–11 focus on issues related to demography more broadly, such as the disruption of lifeline networks as key infrastructure elements, gender aspects of resilient urban design and the role of communities in disaster recovery. Chapter 12 is about international collaboration in the field of disaster studies and highlights, through the author's personal experiences, how scientific ideas and approaches can be exchanged and new connections can be built through case studies across nations.

### **References**

Alexander D (2001) Natural disasters. Taylor & Francis Group, New York.

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### **Chapter 2 Long-Term Mass Displacements— The Main Demographic Consequence of Nuclear Disasters?**

#### **Dávid Karácsonyi, Kazumasa Hanaoka, and Yelizaveta Skryzhevska**

**Abstract** Human history has witnessed several major disasters that have affected the economic, social and environmental conditions of their respective regions. The nuclear disaster of Chernobyl (1986, Ukraine, that time the Soviet Union) and Fukushima (2011, Japan) appears to be the most significant disasters in terms of negative outcomes produced for their population over a long time. Despite this, the analysis of the socio-economic outcomes of these disasters has attracted much less scientific attention than health or radiation-related issues (UNDP 2002a; Lehman and Wadsworth 2009, 2011). Although nuclear accidents are deemed to be rare events, the Fukushima disaster occurred only 25 years after Chernobyl. These disasters highlighted the need for a detailed long-term socio-economic analysis of these accidents to acquire sufficient knowledge to be applied when considering new construction sites for nuclear power facilities (Lehman and Wadsworth 2011). This chapter focuses on the problem of permanent resettlement resulting from nuclear disasters and its effects on regional demographic trajectories and spatial shifts. Based on the results of this study we argue that mass displacement after a nuclear disaster rather than the radiation itself has a much more significant impact on deteriorating health, natural reproduction and economic performance of the affected population. Furthermore, given the differences in radio-ecological conditions, reconstruction policy and the time framework, Fukushima may demonstrate demographic consequences that are different from the Chernobyl case.

D. Karácsonyi (B)

Geographical Institute, CSFK Hungarian Academy of Sciences, Budaörsi út 45, Budapest 1112, Hungary

e-mail<EMAIL_ADDRESS>
K. Hanaoka Department of Geography, Ritsumeikan University, 56-1 Tojiin-kita-machi, Kita-ku, Kyoto 603-8577, Japan e-mail<EMAIL_ADDRESS>
Y. Skryzhevska

Miami University, 202 Mosler Hall, 1601 University Boulevard, Hamilton, OH 45011-3316, USA e-mail<EMAIL_ADDRESS>
**Keywords** Chernobyl · Fukushima · Radiation exposure · Mass displacement · Spatial-demographic consequences · Urbanisation

### **2.1 Introduction**

Human history has witnessed several major disasters that have affected the economic, social and environmental conditions of their respective regions. The nuclear disaster of Chernobyl (1986, Ukraine, that time the Soviet Union) and Fukushima (2011, Japan) appears to be the most significant disasters in terms of negative outcomes produced for their population over a long time. Despite this, the analysis of the socio-economic outcomes of these disasters has attracted much less scientific attention than health or radiation-related issues (UNDP 2002a; Lehman and Wadsworth 2009, 2011). Although nuclear accidents are deemed to be rare events, the Fukushima disaster occurred only 25 years after Chernobyl. These disasters highlighted the need for a detailed long-term socio-economic analysis of these accidents to acquire sufficient knowledge to be applied when considering new construction sites for nuclear power facilities (Lehman and Wadsworth 2011). This chapter focuses on the problem of permanent resettlement resulting from nuclear disasters and its effects on regional demographic trajectories and spatial shifts, while Chap. 11 studies the community involvement during and after evacuation and resettlement process in two nuclear disaster cases.

At first glance, Chernobyl and Fukushima may not be comparable, given the tremendous difference in their socio-economic conditions. The geographic, cultural and socio-economic distances can hardly be greater between any two points on Earth than between Japan during the 2010s and the Soviet Union during the 1980s. However, according to Oliver-Smith (2013), geographically and culturally distanced societies present analogous issues during similar disaster events. For instance, Chernobyl and Fukushima both deployed similar policies to manage mass population displacements. An initial emergency evacuation was followed by organised or spontaneous resettlement of the vulnerable population to avoid further radiation risks. The radiation threat should be considered as both a rapid-onset disaster because of the urgent need of evacuation and a slow-onset disaster because of its long-lasting effect, making a return difficult or even impossible over time.

The Chernobyl and Fukushima disasters illustrate how long-term emergency mass displacement triggers demographic shifts. They are not the largest evacuations in human history; however, they are among the largest permanent resettlements in peacetime caused by a previously unforeseen, unplanned situation.

Geographically detailed data is necessary to understand spatial turbulences caused by mass displacement after the Fukushima and Chernobyl disasters. In this study, data series spanning over three decades was used to provide insights into long-term population shifts after Chernobyl based on census populations. In the Fukushima case, mobile phone location data was used alongside the census data in spatially fine-scale to interpret population changes. This provides short-term but spatially and structurally detailed data about the effect of mass displacement. This detail is used to explore the difference between de facto and de jure populations which could be significant during the post-disaster evacuation phases. Thus, the findings derived by analysing the two data sets can complement each other.

The core analysis used Geographic Information Systems (GIS) based on detailed spatial units that included the territories of Belarus, Ukraine, nine western provinces of Russia and the Tohoku area located on the northern part of Honshu the main island of Japan.

### **2.2 Spatial Demography Impact of Mass Displacements**

Relocation or resettlement of disaster-stricken populations is a common strategy applied within disaster mitigation policy (Oliver-Smith 1996). Generally speaking, displacement is the impact of a disaster which results from the vulnerability of people to shocks or stresses, compelling them to relocate just for survival (Lavell and Ginnetti 2013). Migration has always been one of the most important survival strategies adopted by people facing natural hazards or human-caused disasters (Hugo 2008).

Along with the demographic loss (death tolls and injuries) caused directly during the disaster event, it could be argued that population displacement can be viewed as the other demographic consequence of a disaster. Mass displacement also has direct effects such as death, injury, disease (Robinson 2003) and could cause social insecurity and disrupted life prospects. Displacement, the demographic and social impacts of which are oftentimes underestimated, can be an even more significant consequence of a disaster than the direct death toll.

A large number of studies on the health and natural reproduction consequences of Chernobyl mostly explained the demographic losses resulting exclusively from radiation. However, they often neglected the impact of mass displacement itself. In the 30-year period after the Chernobyl disaster, the number of indirect victims (deaths caused by cancer, cardiovascular diseases, etc.) is still widely debated (TORCH 2006, 2016; Peplow 2006 or see Greenpeace 2006) because the linkage between radiation and cancer cannot be proven due to its stochastic occurrence within the population (see WHO 2006, 2016; IAEA-WHO-UNDP 2005; IAEA 2006). The only two exceptions are the increase of thyroid cancer cases among those who were young and adolescent during the disaster (4000 cases by 2002 according to IAEA 2006; OECD 2002) and leukaemia that occurred after 1990 among former on-site emergency clean-up workers (*likvidator*s) (Hatch et al. 2005; Balonov et al. 2010; European Commission 2011).

Despite there being a large number of health studies, science still lacks full, final and objective information about the medical and biological consequences of Chernobyl (UNDP 2002b; Hatch et al. 2005; Baverstock and Wiliams 2006 and others). Studies investigating health issues resulting from nuclear disasters are limited as a result of the lapse between initial exposure and the presentation of symptoms. This lapse can be as long as 10–20 years after the accident (Lehmann and Wadsworth 2011). Extreme variations in individual exposure causing tragic outcomes are impossible to follow up over long periods of time when analysing large populations. Considering also that the screening effect inflates health statistics when populations in the affected area experience intense health control that identifies illnesses which would otherwise never be explored (UNDP 2002a). It is estimated that the indirect death toll varies from 4,000 (Peplow 2006; IAEA 2006) to 60,000 (TORCH 2006).

Studies on natural population reproduction trends often did not prove a mathematical correlation with radiation exposure after Chernobyl (IAEA 2006). According to Linge et al. (1997), the birth and death rates during 1986–1996 were similar to those in non-affected areas. However, their investigations were based on the populations of larger regions, potentially cloaking extreme local variations. Other studies (see Omelianets et al. 1988, 2016; Lakiza-Sachuk et al. 1994; Voloshin et al. 1996; Rolevich et al. 1996) claim radiation exposure temporarily decreased birth rates immediately after the accident in the affected areas. However, this decrease can be explained by the disinclination to bear children during the uncertain life prospects that eventuated post-Chernobyl resettlement (Abbott et al. 2006). It can also be explained by the fear of the effect of radiation exposure during pregnancy instead of the presence of radiation effect itself (Jaworowski 2010). This view is supported by Lehmann and Wadsworth (2011), who states that contamination levels have little or no influence on fertility, marriage behaviour and education performance. This is further illustrated by a lack of statistical correlation between radiation exposure and chromosome aberrations or birth defects (OECD 2002; Baverstock and Williams 2006). According to the research by Rolevich et al. (1996), Libanova (2007), and Mesle and Poniakina (2012), there is higher mortality among people living in the affected areas. However, the increase in mortality cannot be explained by the radiation alone (Shestopalov et al. 1996). The increase of psychological problems caused by the social disruption during the resettlement presented significant health consequences (Brenot et al. 2000; Balonov et al. 2010). Furthermore, as younger generations migrate out of the disaster area (Voloshin et al. 1996; Omelianets et al. 2016), a statistical consequence is an increase in mortality simply because of the shift in age structures towards aging.

Although approaches cited in the previous paragraph often appear opposing, it is very important to stress that even if the results are biased that the majority of scientists agree that the Chernobyl disaster as a whole played a significant role in the deteriorating natural reproduction during the 1990s. Natural reproduction decline was also related to general socio-economic decay during and after the collapse of the Soviet Union, such as growing poverty and unemployment, increasing alcoholism and poorer medical services (Ioffe 2007; Baranovski 2010; Marples 1993, 1996 and others). As such, it is hard to distinguish the two separate effects.

Out of the health and natural reproduction studies, only a few research focuses on wider demographic consequences. Lehmann and Wadsworth (2011) underline the lower market performance of those who were exposed to higher radiation. This effect however is based on the self-assessment of their own health condition as poor, not directly from the radiation. These people also have lower mobility. Abbott et al. (2006) approached the socio-economic effect of Chernobyl through the view of risk and uncertainty when analysing poor economic circumstances. The most significant documentation on Chernobyl-related social and economic issues has been launched by UNDP (2002a as well as 2002b, c), calling for the need of a new developmental approach. According to this document, a holistic approach integrating health, radio-ecology and economic aspects is needed to fully understand Chernobyl.

Based on the literature, we argue that the main direct negative demographic impact of Chernobyl was not the number of deaths or illnesses, not even the psychological consequences (see Rumyantseva et al. 1996; Lochard 1996; Brenot et al. 2000 or Jaworowski 2010) but the urgent need for the resettlement of ten-hundred thousands of people because of the long-term radiation threat. This resettlement resulted in the distortion of everyday life and changed natural reproduction due to post-disaster uncertainty and social insecurity. Post-Chernobyl and post-Fukushima displacement caused much more significant demographic shifts than the radiation itself. Thus, the effect of permanent mass displacement should be the focus when explaining demographic outcomes.

Permanent resettlements resulting from disasters are relatively rare events hence less discussed in the general disaster literature (Oliver-Smith 2013) despite having a long-term demographic impact. Flooding, earthquakes and volcano eruption can cause large evacuations but rarely long-term displacements. However, long-term demographic shifts can be caused by temporary resettlement during or following a natural hazard event as well as it discussed in Chaps. 5 and 6. If a displacement caused by natural hazards becomes permanent, this indicates failed remediation policies (Oliver-Smith 2013). Yet there is no clear distinction between temporary (short-term) and permanent (long-term) displacement in the literature. As previously identified, such a distinction can often be policy induced. In Fukushima, policy documents refer to evacuees as temporarily displaced people to maintain hope for a return and to keep communities together (see Chap. 11). A displacement can last for years, even for life and still, it is described as "temporary".

Furthermore, mass displacement in practice often does not solve the problem caused by the disaster itself but generates new challenges (Robinson 2003). In many cases, the resettlement results in a secondary disaster (Oliver-Smith 2013), which will further produce serious consequences in a badly planned or unplanned resettlement (Cernea 2004). At a new location, an appropriate settlement design, housing, services and an economic base need to be built to enable people to revitalise itself and achieve adequate levels of resilience (Oliver-Smith 2009). These challenges caused by mass displacement should also be considered as integral parts of the Chernobyl and Fukushima disasters. We argue that the lack of a holistic view led to an overemphasis of health risks by radiation which neglected the effect of the main consequence of nuclear disasters: permanent mass displacement and the uncertainties and disturbances caused by it.

### **2.3 Changing Region and Shifting People by Nuclear Disaster**

Nuclear radiation levels significantly determine evacuation and resettlement policies rather than an understanding of the key findings from the literature summarised in the previous section whereby radiation exposure itself has a minor effect directly on general demographic trends. The radiation is not a homogenous phenomenon, it has changing levels, composition and characteristics over time, and thus, the evacuation and resettlement measures follow this change to cope with the changing radiation threat. Based on this, certain radiation phases can be distinguished over time which results in an adjustment of resettlement policies following the disaster. Thus, the level of radiation and change in population trends are strongly interrelated through the resettlement policies rather than through health consequences. There are important differences between Fukushima and Chernobyl in terms of the composition of emitted isotopes resulting in the slightly different evacuation and resettlement policies. In the following section, these different and changing characteristics of radiation will be presented to better understand evacuation and resettlement measures in the two cases.

### *2.3.1 The Chernobyl Case*

In 1986, at the Chernobyl nuclear power station, the operation failure and poor engineering design that led to an explosion in Unit 4 within the reactor core<sup>1</sup> which damaged the shielding, released 3–4% (5–6 tonnes) of fragmented nuclear fuel2 into the surrounding environment and was followed by a ten-day graphite fire. The accident caused a release of fission products into the environment, which was the

<sup>1</sup>A runaway nuclear chain reaction caused a steam blast within the reactor vessel that was followed by a larger chemical explosion seconds later either by hydrogen–air or carbon-monoxide–air ignition. The magnitude of the reactor core explosion and resulting release of fuel was unprecedented in the history of nuclear accidents, e.g. in Fukushima, in Three Mile Island or Windscale.

<sup>2</sup>The reactor that exploded in Chernobyl used low-enriched uranium-oxide fuel with 2% 235U and 98% 238U. The spent fuel still consists of ~96% 238U as well as <1% 235U, 236U and ~1% transmuted isotopes such as 239Pu, 240Pu and other trans-uranium elements, which emit alpha radiation (high energy 4He nuclei) when decaying. These isotopes are harmful when inhaled (causing lung cancer) or ingested in small quantities, but human skin stops alpha radiation.

On the other hand, during normal reactor operation, most of the fissile isotopes (82% of 235U, 62–73% of 239Pu and 72% of 241Pu), representing ~2 to 3% of the total fuel mass, will undergo fission when capturing a neutron instead of transmutation, producing short and medium half-life products such as 131I (beta emitter), 90Sr (beta emitter) and 137Cs (beta and gamma emitter, a decay product of very short-lived 137Xe). Although the total amount of such material released was less than 0.5 kg for 131I and less than 25 kg for 137Cs, it represents a significant danger because beta radiation (emission of high energy electrons or positrons) and especially gamma radiation (high energy photons) can penetrate human tissue, making it hazardous even without actual intake of the isotope.

principal source of high initial effective doses<sup>3</sup> in large areas that extended outside of the Soviet Union. However, the isotopes with a short half-life<sup>4</sup> rapidly decay (UNDP 2002b), such as 131I (Iodine-131) which was found to be the root cause of increased thyroid cancer cases after the disaster. One year after the accident, the total effective dose levels dropped to 2% of what it had been at the time of the accident, and after two years, it had fallen to 1% (IAEA 2006). Among those isotopes that remained over long time,<sup>5</sup> the largest area (Table 2.1) was polluted by 137Cs (Caesium-137), which is the predominant source of the remaining dose levels causing a health risk since the third year after the disaster.<sup>6</sup>

After the Chernobyl disaster, two solutions—or their combination—were employed to mitigate the effects on the local population: radiological decontamination and the resettlement of people to non-contaminated areas. Establishing new homes for resettlement seemed clearly more expensive but was also the much safer solution (Tykhyi 1998).

The most severely contaminated area was the surroundings of the power plant with a radius of 30 km, the so-called "Exclusion Zone" including the plant itself, as well Pripyat city with 50 thousand people (1986), Chernobyl town and several villages. The total population of this area (116 thousand people) (Table 2.1) was evacuated during 1986–1987 (UNSCEAR 2000; IAEA 2006) mostly to large cities such as Kiev, Minsk, Chernihiv, Zhytomyr (Lehmann and Wadsworth 2011), was their communities quickly dissolved (Voloshin et al. 1996; IOM 1997). Many of them were settled later in Slavutich, a town established in 1988 for evacuees from Pripyat (Voloshin et al. 1996; Mesle and Poniakina 2012). The "Exclusion Zone" remained closed even until today. It is only opened in special cases such as for a very small number elderly and voluntary repatriates (*samosyoli*) (Lochard 1996).

The concentric zoning was adjusted in 1988 based on the survey results of 137Cs surface activity levels7 (Fig. 2.1). At the same time, the definition of "Contaminated Area" (137Cs activity is above 37 kBq/m2),8 as well as an additional "Resettlement

<sup>3</sup>Effective dose is measured in Sieverts (Sv) defined as the total amount of energy from ionizing radiation absorbed by the human body, measured in J/kg.

<sup>4</sup>Half-life of these released isotopes: 132Te 78 h, 133Xe 5 days, 131I 8 days. This means that half of the initial amount of each isotope present will have decayed over this time. E.g. 131I 100% on day 1, 50% on day 8, 25% on day 16, 12.5% on day 24 and so on.

<sup>5137</sup>Cs has a half-life of 30 years, 90Sr 29 years, 239Pu 24 thousand years and 240Pu 6.5 thousand years.

<sup>6137</sup>Cs is highly soluble in water. Thus, its salts are more easily integrated into parts of the food chain and easily adsorbed in human soft tissues (particularly the cardiovascular system). Its biological half-life is only 2 months; thus, it is rapidly excreted on intake. Unlike 137Cs, 90Sr has a biological half-life of 20 years and absorbed into the bones. This prolonged exposure caused leukaemia amongst clean-up workers in the evacuation zone (Balonov et al. 2010).

<sup>7</sup>Activity, given in becquerels (Bq) or curies (Ci), is a measure of the total number of nuclear decays per second occurring in a certain quantity of radioactive substance. Activity by weight of radioactive material can be expressed as Bq/g, and average surface activity level can be expressed as kBq/m<sup>2</sup> or Ci/km2. 1 Ci <sup>=</sup> 3.7 <sup>×</sup> 1010 Bq.

<sup>8</sup>Staying in an area where 137Cs activity is 37 kBq/m2 is equivalent to receiving an effective dose of 0.25 <sup>µ</sup>Sv per hour (the human body absorbs ~0.25 <sup>×</sup> 10–6 J energy per kg every hour from beta

**Table 2.1** Zoning in Chernobyl, compared to Fukushima (Based on IAEA 2006; UNDP 2002a)

Zone" (137Cs activity above 555 kBq/m2) was established (UNSCEAR 2000; IAEA 2006). The latter was subject to further obligatory evacuation and resettlement. The general position was that in the mainly rural areas where healthy foodstuffs could no longer be produced in agriculture, it was futile to compel the local population to stay. Decontamination efforts were suspended in those areas where the local population

and gamma-decay). This effective dose over one day is equivalent to one dental X-ray check (which is ~5 µSv), or eating 2.5 bananas every hour (0.1 µSv) (Banana contains naturally occurring <sup>40</sup> K). During a standard air flight, the average dose is 2–4 µSv/h, while during a flight by Concorde, it was 9–10 µSv/h.

**Fig. 2.1** Affected areas by Chernobyl and Fukushima disasters (Author and cartography by Karácsonyi, 137Cs contamination data by USCEAR 2000)

would receive a 70-year ("lifetime") extra effective dose<sup>9</sup> of at least 350 mSv (milli-Sievert) (Malko 1998), and residents of these areas, 220 thousand people, were also resettled to non-contaminated areas at the very beginning of the 1990s (UNSCEAR 2000; IAEA 2006). The 350 mSv concept became the subject of sharp criticism (Malko 1998) given the impossibility of determining the dosage for each person leading to questioning the calculations made for the resident population as a whole. This inevitably caused mistrust among people.

Majority of subsequent resettlements happened in Belarus, until 1996, when these measures were finalised there. This second wave was followed by a more moderate one during the late 1990s only in Ukraine by the resettlement of additional 50 thousand people until 2005 when the process was officially ended there as well (IAEA 2006).

There are no exact records available on the total number of people that moved in the three affected countries, the numbers vary between 300 and 500 thousand which

<sup>9</sup>The average daily global background dose on the Earth's surface is 100 µSv which means, people who exposed 350 mSv extra dose throughout their lifetime, they exposed to at least ~10% higher background radiation caused by Chernobyl.

**Table 2.2** Estimated number of people affected by post-Chernobyl resettlement/evacuation by country and by time frame (Based on UNDP 2002a; UN 2002; IOM 1997; UNSCEAR 2000; IAEA 2006; Lehmann 2011)

includes voluntary resettlement as well (326,000—IAEA 2006; 350,000—UNDP 2002a; IAEA-WHO-UNDP 2005; 492,000—UN 2002) (Table 2.2). Outside the "Resettlement Zone", in areas with 137Cs activity levels between 185 and 555 kBq/m2, people were free to decide to stay or to leave. A legal act provided dwellings for those displaced. In these areas, economic restrictions, such as in agriculture, were coupled with increased health and food control.

It was reported that around 5–6 million people (IAEA-WHO-UNDP 2005; Balonov et al. 2010) lived in "Contaminated Areas" as of 2005, and still 200 thousand (IAEA 2006; Balonov et al. 2010) resided in the "Resettlement Zone". We estimate that by 2010, approximately 5 million people still lived in areas where radiation exposure exceeded 0.25 µSv/h (137Cs activity over 37 kBq/m2) in 1986 (Table 2.1). As a result of the natural isotope decay and purification processes, the exposure significantly decreased from 1986 which allowed the zoning to be readjusted (IOM 1997; UNDP 2002b). The only exception is the closer area surrounding the accident site in the "Exclusion Zone". It was polluted by 241Pu which has a relative short half-life and decaying into 241Am, a much more radio-toxic isotope.10

<sup>10241</sup>Pu (a beta emitter) has a relatively short half-life (14 years), but its decay product 241Am (an alpha and gamma emitter, half-life: 400 years) is much more radio-toxic. In contrast to other isotopes, there will be a natural increase in 241Am activity over time. By 2058, the 241Am activity will surpass the cumulative activity of all trans-uranium isotopes (UNDP 2002b) and reach its maximum concentration a hundred years after the accident (IAEA 2006). Because of its longer half-life, it will surpass the activity of 137Cs 300 years after the accident, significantly slowing the natural purification within the "Exclusion Zone".

### *2.3.2 Fukushima—The Accident, Zoning, Regulation, Consequences*

On 11 March 2011, the Great East Japan Earthquake (moment magnitude of 9.0) and subsequent huge tsunami hit the two nuclear power plants (Fukushima I and II or Fukushima Daiichi and Daini) in Fukushima Prefecture. According to the official government report (NAIIC 2012), all nuclear reactors stopped safely after the earthquake. However, soon after the earthquake water from the tsunami wave, which was higher than 14 m, flowed into the nuclear power plants over the seawall. At the Fukushima I nuclear power plant, four out of six nuclear reactors lost their cooling functions because all the emergency backup generators were destroyed or drained by the huge tsunami. Three nuclear reactors then experienced a nuclear meltdown, and hydrogen–air chemical explosions occurred outside the reactor vessel.

Due to the accident, a large amount of fission products, mainly 131I, 134Cs and 137Cs, were released into the ocean and the atmosphere. The total amount of radioactive materials released was estimated to be 770,000 TBq by the Nuclear and Industrial Safety Agency and 570,000 TBq by the Nuclear Safety Commission (TEPCO 2011). Steinhauser et al. (2014) reported around 5,300,000 TBq in case of Chernobyl and 520,000 TBq in case of Fukushima. These numbers mean that the long-lasting effect of Fukushima is significantly lower than Chernobyl; however, the threat during the accident was almost on a similar scale. In particular, radioactive materials spreading in a north-western direction from the nuclear power plant made a huge geographic area highly contaminated. During the evening of 11th March, the Japanese government declared a nuclear emergency. On the same day, an evacuation order was initially issued to the area within a 3 km radius of the power plant, but this was increased to a 30 km radius until 15th March. Group evacuations of residents were carried out by municipality offices on the morning of 12th March. At the same time, many residents who could drive cars evacuated individually.

After the nuclear accident, government organisations started to measure accurate aerial radiation levels with aeroplanes, helicopters and cars. Also, radiation levels were monitored continuously by at least 1600 monitoring posts installed across Fukushima Prefecture. The geographical extent of the highly contaminated area in Fukushima is limited compared to the Chernobyl case (Imanaka 2016; Steinhauser et al. 2014). However, 137Cs is expected to remain for a long time (Fig. 2.1).

In April 2012, since the nuclear reactors were confirmed to be cooled down, the evacuation areas were reorganised into three based on their annual radiation dose as of March 2012: (1) areas where it is expected that the residents will have difficulty returning for a long time (above 50 mSv/year), (2) areas in which the residents are not permitted to live (20 mSv-50 mSv/year) and (3) areas for which the evacuation order is ready to be lifted (below 20 mSv/year). The Japanese government accepted the 20 mSv/year rule during rehabilitation period according to recommendations by ICRP Publication 111 (ICRP 2009) in comparison with the 5 mSv/year (or 350 mSv during 70 years) rule introduced after Chernobyl. Inside the evacuation areas, the total population was 81,291 people over an area of 1150 km2. Among the population, 24,814 people resided within the highest contaminated area (above 50 mSv/year), whose size is 337 km<sup>2</sup> (Team in Charge of Assisting the Lives of Disaster Victims, Cabinet Office 2013). In 2015, the evacuation order was lifted for some parts of the evacuation areas, but five municipalities remain completely within evacuation areas and another three are partially included. In all the evacuation areas, previous residents are not allowed to stay overnight without special permission. In the highest contaminated area, all entrance roads to the area are blocked, and previous residents are currently not permitted to enter.

In the area affected by Fukushima disaster, large-scale decontamination is now underway (Ministry of Environment 2017). In fact, owing to natural degradation and decontamination work since the disaster, some parts of the evacuation areas meet the criteria for the order being lifted; the annual air dose has dropped to a level below 20 mSv per year, infrastructure and basic amenities such as supermarkets, hospitals and post offices can be reconstructed, and close consultation with municipalities achieved (Nuclear Emergency Response Headquarters 2015). In areas where the evacuation order was lifted, previous residents are permitted to return. On the other hand, in areas with the highest contamination levels, it was expected that residents would not be permitted to enter for a long time. The Japanese government, however, revised their legislation in an attempt to encourage residents to return there in five years or so by selecting prioritised sites for intensive decontamination and reconstruction which is named "reconstruction base".

### **2.4 Data and Methods**

This research analysed and mapped population census data related to the Chernobyl (1979–2010) and Fukushima (2005–2015) affected regions. Demographic trends in the Chernobyl affected area at district (*raion*) level were derived from population censuses extending three decades following the disaster. In conjunction with the final two censuses under the Soviet Union (1979, 1989),11 the censuses from the successor states were also used noting their time and methodological deviation. These included Belarus in 1999 and 2009, Ukraine in 2001 and Russia in 2002 and 2012. To further Ukraine's 2001 census data, the 2010 registered resident population number and composition data were included because there was no further census held in Ukraine after 2001 and until the publication of this chapter.

This investigation used a consolidated spatial system that included 846 units based on district-level (*rayon*) data. This data was free of administrative boundary changes that covered the entire territory of Ukraine and Belarus, as well as nine western regions (*oblast*s) of Russia (Fig. 2.1). This wider territory included the evacuation areas as well the evacuee receiving sites, where the post-Chernobyl evacuation and resettlement could have a fundamental impact upon the demographic processes. For an exact determination of the impact of the disaster, the share of 137Cs contaminated

<sup>11</sup>The Soviet Union dissolved in 1991.

area within the area of each spatial units (districts) was taken into account and ArcGIS was utilised for calculations. The radiation level data was provided by UNSCEAR (2000).

As evacuation is still underway in the Fukushima-affected area, understanding displacement after the accident is a difficult task. Resident registration and questionnaire surveys of evacuees are important data sources. However, at the time of writing this chapter, the former provides information on registered residents only. Response rates to the latter are now around 50–60%, and the tabulated data published is inadequate for demographic analysis. Recently, the results of the Japanese population census 2015 were released. The census form, which asked about demographic characteristics as well as locations of residence five years ago, provides information on migration from highly contaminated areas. The geographic unit for this study is the municipality level (*Shi-Cho-Son*).

As a shortcoming of the census data, the data can only capture night-time populations who have resided in their current place continuously for at least three months. Although evacuation areas are lifted every year and temporal visitors increase after that, we cannot understand such changes in the ambient population by utilising census data. In Japan, as a new form of dataset, ambient population datasets based on 70 million mobile phone users' locations, named "mobile spatial statistics", are released at the 500 m grid cell level. The technical details of the dataset are explained in Terada et al. (2013) and Oyabu et al. (2013). The ambient population datasets we have shown the average of the hourly population in June 2015 and June 2016. Since the ambient population before the accident is not available, the census population in 2010 at the same 500 m grid cell level was used in combination to understand the geographical distributions of population change from 2010 to 2015.

### **2.5 Demographic Impacts on Regional Scale**

### *2.5.1 Chernobyl Disaster—Shifts of Three Decades*

The population of Polesye region, where Chernobyl disaster occurred, has been decreasing since 1970 (Khomra 1989), first to a moderate extent, then at a higher rate since 1986. The data series spanning three decades since the disaster reveals that the consequences of the Chernobyl accident are reflected most characteristically by the demographic trends of the 1990s even though evacuation measures can be reached back to the 1980s (Fig. 2.2). This is partly because during the census in 1989, three years after the disaster, many people still stayed in the evacuation zone and received permanent housing in the following years after that.

The annual population growth of Ukraine amounted barely to 200,000 in the 1980s. Such a wave of resettlement mobilising 100,000 in 1986–87 and additional 100,000 during the following ten years thoroughly reshaped the total population pattern in large part of the country. In Belarus, the population increased in the 1980s by

**Fig. 2.2** Average annual population change by rayons (Author and cartography by Karácsonyi, calculation based on 1979, 1989 Soviet, 2001 Ukrainian, 1999, 2009 Belarusian and 2002, 2010 Russian census populations as well as de jure population in Ukraine by 2010)

around 30,000 people each year, while in consequence of the Chernobyl disaster, 25– 30,000 people were resettled in 1986–87, followed by additional 100,000–130,000 during the 1990s in a country with a population of barely 10 million. The effect was even more dramatic because the evacuation affected around 1–1.6% of the country's total population. The corresponding figure was 0.4% in Ukraine and 0.04% in Russia. Even in 2010, Belarus had the highest share of population living in contaminated areas (Tables 2.3and 2.4). No other country has experienced the impact of a nuclear accident to the same degree. Given the large number of people who were resettled, the recipient regions—in particular the major towns and their environs—saw a relatively more favourable demographic trend in the 1990s.

**Table 2.3** People living in administrative units in 2010, where radiation dose was higher than 0.25 µSv/h during Chernobyl (in 1986) and Fukushima (in 2011) disasters

aBefore the disaster, they became affected one year later

**Table 2.4** Share of population and area of administrative divisions in selected countries in 2010, where radioactive contamination was higher than 0.25 µSv/h after Chernobyl (in 1986) and Fukushima (in 2011)

aBefore the disaster, they became affected one year later

When reviewing the entire affected area within the three countries, a general dependence of the population change on the proportion of areas of radioactive contamination was only apparent in the 1990s (Table 2.5). The internal population change of entire Ukraine and Belarus was strongly under the influence of the resettlement measures rather than by natural change or other types of internal migration between 1989 and 2001. In Russia, the depopulation of affected areas was less significant. Because of dissolution of the Soviet Union, a large number of ethnic Russian political refugees from other republics arrived and resettled into these areas counterbalancing the out migration caused by the disaster (Veselkova et al. 1994).

From the 2000s, a significant correlation between population change and the share of contaminated areas could not be found. Demographic "waves" of resettlement calmed down by the 2000s, and even returning migration to the former places could be detected. The population of several small towns that lay in the contaminated areas in Belarus but had been cleaned−up (Naro˘ulia, Brahin and Chojniki) began to grow once more (Table 2.6). In these towns that have undergone complex rehabilitation, people receive significant state assistance as well as apartments built with governmental funding. In such small towns, the presence of young families with small children is striking. For this reason, in the contaminated areas, the population is becoming urbanised more rapidly than elsewhere. These areas have become

**Table 2.6** Change of total population of some towns in contaminated area

aOutside the contaminated area

Belarus's "most rapidly urbanising" regions (Table 2.5). The ratio of urban population is on the increase in Ukraine as well, but it is also a result of its close location to the Kyiv agglomeration.

Chernobyl did not change the direction of regional population dynamics. The decline in population would be significant even without Chernobyl; however, it did accelerate the process. The population density was low even before the disaster, and the evacuations merely accentuated this state of affairs. Natural population reproduction data (crude birth and crude death ratio) around 2010 does not reflect any correlation with higher radiation levels any more, suggesting the decline in the birth rate was only temporary after the disaster and connected with the uncertainties because of resettlement. The disaster did, however, fundamentally alter the urbanisation processes and the network of villages. Smaller villages in remote areas disappeared in significant numbers, whereas small towns and minor urban centres became relatively more "stable".

The negative demographic processes of the Polesye combined with the disastercaused outmigration and resettlement poked a huge hole in the demographic space of the region, which is especially spectacular in the changing population density within rural areas. Even the districts outside the evacuated zone became the most sparsely populated areas of Belarus and Ukraine (Fig. 2.3).

**Fig. 2.3** Population density by rayons (Author and cartography by Karácsonyi, calculation based on 1979 Soviet, 2009 Belarusian, 2010 Russian census populations as well as de jure population in Ukraine by 2009)

### *2.5.2 Fukushima—Recent Demographic Processes*

Regional population structure changed fundamentally after the construction of the nuclear power plants in the coastal area of Fukushima Prefecture. According to a case study conducted in Tomioka Town by Kajita (2014), residents consisted of three groups: (1) people who lived in the area originally, before the construction of the nuclear power plant, (2) "newcomers" who migrated there to work for construction and electric industries and had already settled for a long term and (3) short-term stayers who were sent by TEPCO and other related companies. Overall, the total population increased in the 1970s when people migrated for work. However, during the 1990–2000s, it gradually decreased again or levelled off. Along with such population decline, the elderly ratio (people aged 65 years and over) went up to around 20–30% in 2010.

The nuclear accident had almost irreversible impacts on regional population structure. As we explained above, group evacuation was organised by municipality offices, and evacuees temporally stayed at city halls, schools and hotels in nearby major cities such as Iwaki, Fukushima, Koriyama and Nihonmatsu. An exception is Futaba, which chose Saitama Prefecture, located around 200 kms away to the south. Understandably, some people outside the evacuation areas escaped farther, stayed at their friends' or relatives' houses temporarily and after that found new houses by themselves. According to official statistics, the total number of evacuees including both ordered and voluntary evacuations reached the maximum number (164,000 people) in May 2012 and 79,000 people remained evacuated as of February 2017 (Asahi 2017a).

In Japan, there are two types of temporal houses provided for evacuees by municipality: prefabricated houses specially constructed after the accident and existing rented houses that municipalities leased. The maximum number of house units provided was 16,800 in 2013 for the former type and 25,554 in 2012 for the latter type (Fukushima Prefecture 2017). Evacuees from the same municipality were arranged to stay in the same prefabricated house complex to maintain the original community and human network (Fig. 2.4). As the map suggests, most of them are located in major cities where infrastructures are provided and daily necessities are easily purchased. In contrast, the detail spatial distribution of households staying in rented houses is not publicly reported, but it can be assumed to be more dispersed and close to major cities based on the locations of housing supply before the accident.

The Japanese population census 2015 provides insights about where people were displaced after the accident (Fig. 2.5). Table 2.7 provides the proportion of evacuees who live outside or inside Fukushima Prefecture by five municipalities which lost their population almost completely after the accident. For those who stay in the prefecture, the proportions of current residences in four major cities are presented. Analysing the proportions disaggregated by age group, we found that the younger they are, the more they are likely to leave Fukushima Prefecture. Around 30–40% of people aged below 40 years old choose to find new residence outside Fukushima Prefecture, for example, Tokyo Metropolitan Area and Sendai in Miyagi Prefecture. Young people can choose a new place which is distant from their home municipality because they have less economic and social capital which keeps them staying in an area closer to their previous residence (Isoda 2015).

As far as those who remain in Fukushima Prefecture are concerned, people are likely to select the nearest major city. For example, in the case of Iitate Village, 60– 70% of residents among those who remain in Fukushima Prefecture chose Fukushima city located 35 kms away. Around 40% of residents from Tomioka selected Iwaki. These results partly reflect the fact that about 55,239 people still lived in temporary houses at the end of September 2015 (Fukushima Prefecture 2017), when the Japanese population census was carried out. The figures in Table 2.7 partially include people already resettled. According to questionnaire surveys conducted by the Reconstruction Agency (2016) in 2015–2016, around 30–40% of affected families bought a new house and settled in a new community. Furthermore, based on the number of recipients of special provisions for housing acquisition, 85% of them seem to have found a newly owned house in Fukushima Prefecture (Asahi 2016). The locations of new houses are likely to be in major cities because land prices in places such as Fukushima City, Iwaki City have increased or at least levelled off.

The sudden population increase caused by mass displacement unintentionally led to several complaints among residents in receiving municipalities. For example, local newspapers reported that traffic jams became more frequent, the queues in hospitals were longer, and housing rent increased. It should also be noted that junior and high school students evacuated from Fukushima-affected areas experienced bullying

**Fig. 2.4** Locations of temporary housing complexes in Fukushima Prefecture (Author Hanaoka, cartography by Hanaoka and Karácsonyi, data from www.pref.fukushima.lg.jp/sec/41065d/juutak utaisaku001.html)

**Fig. 2.5** Total population change by municipalities (Author and cartography by Karácsonyi, calculation based on 2010, 2015 Japanese census populations)

 average ( = age group: ) are presented Distance in brackets is based on the shortest path between two municipal offices calculated by Google Maps concerning the nuclear accident at school. In this way, resettlement after the nuclear accident, unfortunately, has been accompanied by various hardships in the new environment for evacuees. Figure 2.6 shows those municipatities where evacuees were

**Fig. 2.6** Changing population dynamics after 2011 (Difference between population change of 2005–2010 and 2010–2015) (Author and cartography by Karácsonyi, calculation based on 2005, 2010, 2015 Japanese census populations)

hosted (red colour), changing the demographic trends between 2010 and 2015 in these settlements.

In Fukushima, affected municipalities are planning several resettlement sites outside evacuation areas, but they seem to be temporal, not permanent resettlements. This is because firstly, some evacuees' wish to return to their hometowns, and secondly, permanent resettlement sites managed by the affected municipality in the receiving municipality are practically difficult under the current Japanese local government system. There are several issues to solve, such as whether dual resident registration can be admitted or not and how to share taxes and public services among municipalities (Tsunoda 2015). Therefore, in principle, affected municipalities are making every effort to enable residents to return to their homes through decontamination. The evacuation order has already been lifted for some evacuation areas, and radiation levels dropped as a result of the natural degradation and decontamination. In the spring of 2017, the evacuation order excepting the highest contaminated area was lifted for the majority of evacuation areas in Iitate Village, Kawamata Town, Namie Town and Tomioka Town. Approximately, 32,000 people lived there before the accident (Asahi 2017b). The total evacuation areas being lifted until April 2017 was 70% of the initial evacuation areas issued immediately after the accident. Yet, many people decided not to return. They not only worried about the radiation level, but basic amenities (e.g. shops, hospitals) and employment opportunities are limited. For example, in Naraha Town, the evacuation order was lifted for all evacuation areas, which covered 80% of the municipality. According to official town records (Naraha Town 2016), only 781 people, which is equivalent to 10.6% of the total population before the accident, have returned. Among them, the proportion of people aged 65 years and over reached 53% (the elderly ratio in 2010 was 24%).

Young people resettled outside Fukushima Prefecture, while many of the migrants who returned are elderly people. This trend accompanies geographical separations of generations in rural areas where young families and their parents traditionally lived together. In addition, since the 1970s, nuclear industries had attracted many migrants from the outside. Many of the first generations reached or are reaching the age of retirement (65 years old). Thus, it is a difficult question whether such people who migrated from the outside previously and settled for a long time will choose to return again. Pre-disaster population structure characterised by a mixture of rural and industrialised areas makes the estimation of future demographic trends difficult in Fukushima-affected areas.

Using spatial mobile statistics, we mapped the average of hourly population per 500 m grid cell in June 2016 and compared it to 2010 population census data to analyse the changes (Fig. 2.7). Comparing the two maps, we found that the geographic distribution of grid cells with high population density almost remained the same outside the evacuation areas between two time periods, while inside, they disappeared almost completely. In particular, there is no peak in population density distribution in the town centre proximity to railway stations, implying that densely populated residential areas no longer exist after the accident. However, there are several grid cells with somewhat higher population density in areas close to the nuclear power plant in Okuma Town and Tomioka Town. This population distribution does not well

**Fig. 2.7** Population distributions in census and mobile phone data (Author Hanaoka cartography by Hanaoka and Karácsonyi)

overlap with the census one, suggesting that most of the people are temporal visitors such as engineering and technical workers at nuclear power plants.

Eighty percent of the area of Naraha Town, located within the 20 km radius from the nuclear power plant, was previously included in the evacuation areas. As we discussed above, the evacuation order was lifted for these areas in September 2015, and the total number of grid cells with population density above 100 people also increased from 32 grid cells in June 2015 to 41 grid cells in June 2016, among 472 grid cells across Naraha Town. This result may suggest that people already returned in these areas or people can enter them more frequently than before, perhaps in preparation for returning. The Japanese population census is conducted every five years, and it is not able to capture such temporal dynamics of population changes. Using mobile spatial statistics will help to continuously monitor and explore the reconstruction progress after the evacuation areas are lifted.

### **2.6 Discussion and Recommendations**

The mass displacement after a nuclear disaster, rather than the radiation itself has a much more significant impact on deteriorating health, natural reproduction and economic performance of the affected population. Based on the literature and the results of this study, these consequences can be summarised as follows:

Population immigration trends are influenced by employment opportunities. Sectors vulnerable to radiation such as agriculture, fishing, food industry are in decline (IOM 1997; UNDP 2002b), while others requiring a lesser sized or a rotating labour force, such as forestry or nuclear waste storage facilities are maintained. New jobs in health care, engineering, science and construction are also represented.

(5) The returning migration or remaining in place is more common in the case of elderly people. Firstly because they have a higher attachment to the place and because of their age, they are less flexible to start a new life somewhere else. Their expected lifelong exposure is also much lower than for the adolescent population. Therefore, they are more likely to accept the risks associated with living in these polluted areas. In-migration to contaminated areas can also be observed in Belarus recently. However, this results from government policy to attract new settlers, rather than the return of the elderly population.

Unlike the Chernobyl case, in Fukushima, permanent resettlement sites outside the affected area were not organised, and instead, extensive decontamination work and higher accepted radiation thresholds make evacuees legally able to return their original homes within six years or so after the nuclear accident. This was also possible because of lower level of Cs137 contamination and lack of high risk trans-uranium elements. Not to mention that according to some experts (see Hjelmgaard 2016), after the 131I and 137Cs phases (IOM 1997), a third phase related to 241Pu–241Am decay has begun in Chernobyl with health consequences yet to be realised and understood. Given the differences in radio-ecological conditions, reconstruction policy and the time framework, Fukushima may demonstrate demographic consequences that are different from the Chernobyl case. In contrast, the return rate is very low which causes a large drop in population density similarly to Chernobyl.

According to World Nuclear Association (2018), nuclear accidents have a low and decreasing probability. Even though previously unforeseen circumstances always could cause accidents in the nuclear industry (Labaudiniere 2012), bring forth the need for evacuation or even permanent displacement of large populations. There are certain points that should be considered when developing resettlement and redevelopment policy for possible future disaster-stricken regions based on the consequences of past displacements. Most of the following points were not considered in post-Chernobyl but were followed in post-Fukushima mass displacement showing a clear policy improvement and better situation-adapted decision-making.

#### 2 Long-Term Mass Displacements—The Main Demographic … 43

to 50 years onwards following the disaster). The permanent mass displacement should be seen only as the ultimate solution to cope with the consequences of a nuclear disaster. It can cause much larger and longer demography shifts than the distortion caused by a low-level radiation exposure resulting in health problems. People should be provided with reliable information about the threat and assistance if they decide to move. On the other hand, people should be allowed to take the risk if they decide to do so, but compensation is necessary.

(3) The intent to move, stay or return is strongly age-specific, and the return migration should be supported accordingly. Infrastructure redevelopment should be planned in accordance with the demographic shift towards aging populations such as more senior homes, hospitals rather than nursery. Low return rates, falling population density and shifting settlement system towards population concentration and urbanisation are also common consequences. Thus, infrastructure regeneration, reconstruction (roads, railway links) should target these areas.

In summary, the most significant lesson from this study is that a poorly planned mass displacement can cause a larger economic loss than the disaster itself. There were clear differences between the management of Chernobyl and Fukushima disasters in this regard. The post-Chernobyl policies that drove population displacement lacked previous experiences on effect of radiation on human health in large populations. The administrative rigidity of the zoning and lack of financial sources for infrastructure-reconstruction and redevelopment (see also Chap. 11) accelerated further the total population and economic loss in Chernobyl. The knowledge and experience derived from the Chernobyl case helped the decision-making in Fukushima. Townships were opened up for returners in recent years in the Fukushima disaster area is possible because of the lower level of radiation and lack of emitted trans-uranium isotopes. The long-lasting existence of Chernobyl zone contributed significantly to the false view to explain all demographic consequences by the invisible radiation threat presented in and around the "death zone". This delivered a negative image of the entire area, making regional redevelopment even more difficult.

### **References**

and the total number of evacuees are 32,000 people. Still 24,000 evacuees of "difficult-to-return" zone). *Asahi Newspaper*, Morning 28th February 2017, p.1.

selective migration: Analysis of Okuma Town Survey based on human capital theory.) In: ed. Yoshihara, N., Nihei, Y., Matsumoto, M.: *Records of the Victims' Refuge Lives in the Great East Japan Earthquake*, Rikka Press, pp. 544–561.

**Open Access** This chapter is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

### **Chapter 3 Estimating Migration Impacts of Wildfire: California's 2017 North Bay Fires**

**Ethan Sharygin**

**Abstract** This chapter examines a cluster of wildfire conflagrations that hit northern California during October 2017, which resulted in significant loss of housing units (6874 residential structures destroyed or damaged). To assess the magnitude of the migration response and network of destinations, a method to estimate migration drawing from a proxy universe of households with students enrolled in public schools was proposed, using data on school exits and re-enrollments from a longitudinal student database. The analysis finds that a small minority of households affected by the fires moved out of the area. Out of nearly 7800 persons displaced by the central fire complex in one city, this study estimated fewer than 1000 changed neighborhoods; of those, fewer than 500 moved out of Sonoma County. These findings are applicable to other wildfires and localized disasters where a substantial portion of housing is lost but public infrastructure in the region remains intact.

**Keywords** Wildland-urban interface · Wildfire · Natural hazards · Migration · Administrative data

### **3.1 Introduction**

This chapter examines a cluster of wildfire conflagrations that hit northern California during October 2017, which resulted in significant loss of housing units (6874 residential structures destroyed or damaged). The magnitude of migration response was unknown, as was the timing and the network of possible destinations. This chapter provides a standard theoretical framework for understanding fire disasters: their frequency and locations most at risk. It also presents an overview of the 'October 2017 Fire Siege' and the conditions which precipitated the fire followed by a discussion into possible approaches to estimating population impacts. A method is proposed to estimate migration drawing from a proxy universe of households with students enrolled in public schools using data on school exits and re-enrollments from a

E. Sharygin (B)

Population Research Center, Portland State University, Portland, OR, USA e-mail<EMAIL_ADDRESS>
<sup>©</sup> The Author(s) 2021

D. Karácsonyi et al. (eds.), *The Demography of Disasters*, https://doi.org/10.1007/978-3-030-49920-4\_3

longitudinal student database. The analysis finds that a small minority of households affected by the fires moved out of the area. Out of nearly 7800 persons displaced by the central fire complex in one city, this study estimated that fewer than 1000 people changed neighborhoods; of those, fewer than 500 moved out of Sonoma County. These methods and findings are applicable to policies and policy research regarding future wildfires and localized disasters where a substantial portion of housing is lost but public infrastructure in the region remains intact.

Section 3.1 of this chapter discusses the growth of wildfire risk in California over the last and next century. Section 3.2 provides background on the Central Sonoma-Lake-Napa Unit (LNU) Complex fires, in particular the largest, the Tubbs fire in Sonoma County. Sections 3.3 and 3.4, the size of the displaced population is estimated, and previous research on estimating migration discussed. The 'school enrollment proxy method,' a new method of estimating migration, is described along with the results. The closing section outlines limitations of this approach and identifies directions for future research.

### **3.2 Background**

### *3.2.1 Wildfire Hazard in California*

Disasters are a major part of the Californian experience. Throughout American expansion into California, earthquakes, floods, fire, and other catastrophes have played an important role in defining life in the state. A tragic standard was set by the 1906 San Francisco earthquake and ensuing fire that followed, which destroyed 28,000 buildings, displaced at least 200,000 residents, and killed between 500 and 3000 people. Flooding in Los Angeles in 1938 destroyed 5600 buildings and caused over 100 deaths. Earthquakes at Loma Prieta in 1989 and Northridge in 1994 injured thousands and caused billions of dollars of damage. Wildfires in Berkeley during 1923 and then Oakland in 1991 destroyed thousands of residences and emphasized wildfire as a constant threat in urban and suburban parts of the state.

Disasters can be broadly classified into two types of looming threats. Gradualonset disasters include droughts, sea level rising, global warming, while suddenonset disasters would include fires, floods, and earthquakes. Sudden-onset threats are especially important for applied demographers to anticipate and prioritize due to their disruptive and chaotic aftermath and the essential role that demographic data can play in the government response. Sudden-onset disasters have immediate consequences, including mass mobilizations of people and resources.

This paper presents a case study from a series of wildfires in late 2017 that displaced more than 10,000 people in Sonoma County in the State of California. This event presented an exceptional challenge to account for the population of each county and city as of January 1, 2018 and to estimate the size of the affected population and the relocation patterns of people displaced by the fires.

While migration responses to wildfire are the focus of the present research, a broader agenda on disaster demography should consider sequelae of disasters and differential vulnerability (see Chaps. 4, 6 and 10). In the example of wildfires, smoke plumes may have a significant public health impact. Equity concerns are also important. Climate change is expanding the geography of risk and changing the demographic profile of the affected populations (see also Chap. 8). No longer limited to remote areas or vacation homes, vulnerability to wildfire in particular, may be reversing from a progressive to a regressive hazard (Davies et al. 2018; Baylis and Boomhower 2018).

Even though California is one-third forested, many of these forests are in poor health due to a combination of factors that including climate change and inadequate, misguided, or uncoordinated forest management policy. Abatzogulou and Williams (2016) found that climate change was responsible for half of the increase in aridity in Western US forests between 1966 and 2016 and that without climate change the cumulative area burned by fires would be just half of what has occurred between 1984 and 2016. Climate change is expected to continue to increase the frequency and intensity of fires (Keyser and Westerling 2017; Moghaddas et al. 2018).

More than 40% of California housing stock is in areas at heightened risk of fire damage, where housing abuts forest, referred to as the wildland–urban interface (WUI; Hammer et al. 2007). The hills, forests, and peripheries of cities and towns are desirable areas, both for builders and potential residents attracted to their natural amenities. Housing growth in WUI areas in California grew by approximately 20% each decade during 1990–2010, compared to 10% each decade for non-WUI areas even though the WUI accounts for just 10% of land area (Radeloff et al. 2018). This has contributed to more problematic forests due to fire suppression efforts and also exposed an increasing number of residents to increased fire risks.

### *3.2.2 Conditions of the 2017 Fire Season and the LNU Complex Fires*

The year 2017 marked a record fire season in California, with 436 significant fires that burned more than 630,000 ha (CDFFP 2019). Yet, the records set during the fire season of 2017 have already been surpassed. Fires during 2018, notably the Carr fire near the city of Redding and the Camp fire which razed the city of Paradise, were the deadliest (93 confirmed fatalities) and most destructive (650,000 ha) in the state's history. This increase has necessitated the development of a robust toolset for estimating demographic impacts of disasters.

The LNU Complex fires comprised of the Tubbs, Nuns, Atlas, and several other fires deserves special mention. These three conflagrations occurred during October 2017 and in close to each other in the WUI. Nauslar et al. (2018) state that these fires 'pushed the bounds of conventional fire wisdom with the extreme rates of spread, size, and timing.' They affected four counties, but Sonoma County bore the brunt of the population and housing impacts. They affected four counties, but Sonoma County bore the brunt of the population and housing impacts.

Sonoma County is located north of San Francisco, along the California coast of the Pacific Ocean. The county has a great deal of climatic variation, according to elevation and proximity to the ocean. Parts of the county close to the ocean remain cool and moist year-round and can be foggy most days from late afternoon until morning. Inland areas have a more typically Mediterranean climate, with hot, dry summers and cool, wet winters. The Northern Coastal Range of mountains runs on either side of the Sonoma Valley. Its abundance of variable microclimates lends itself well to viticulture, with California's first wineries established in the area in the 1850s. Santa Rosa is the largest city in Sonoma County and was home to 178,000 of the county's 504,000 residents in 2017 (CDOF 2018).

The region had suffered the effects of severe drought since 2011—possibly the worst drought in more than 1000 years (Griffin and Anchukaitis 2014). These conditions contributed to a record high total of 129 million dead trees in the state as of late 2017 (USFS 2018; Guerin 2017; Buluç 2017). In total, the state's tree mortality survey counted 147 million tree deaths during 2010–2018. A normal average would be 1 million tree deaths each year. However, 62 million deaths were recorded in 2016 at the peak of the drought.

As of October 2016, 83% of the state was in drought, and 21% of the state was in 'exceptional' drought status, the most severe category. The first months of 2017 saw high rainfall, which mitigated drought conditions. Most of the precipitation of the 2016–17 season fell during January and February, marking the state's wettest winter and the second-wettest year since records began in 1895 (Di Liberto 2017). The rain fell so fast that it caused flooding throughout the state and damaged the nation's tallest dam, Oroville Dam. The state's drought declaration had been in place since 2014 and was lifted in April 2017. The immense volume of rain was a welcome reprieve to depleted reservoirs but also promoted the growth of shrubs and grasses that typically wither during the hot, dry summer and become fuel for more intense fires (Dudney et al. 2017). Recent research found that the connection between wet weather and fire activity in California has broken down completely during the second half of the twentieth century, as the effect of growth and fuel buildup during rainier seasons created greater fire hazards within the context of increased annual temperatures (Wahl et al. 2019).

The state's seasonal wind patterns are another factor in making California especially susceptible to fires late in the year. Late summer winds, known regionally as the Santa Ana or Diablo winds, can occasionally bring fast hot winds that exacerbate fires. These winds may grow more intense as a result of climate change, although the effect is debated (Jin et al. 2015; Mass and Ovens 2019). These late summer or fall winds were a factor in all of the state's most destructive WUI fires and have long been recognized as 'a wind of bad augury […] at this season of the year' (Russell and Boyd 1923).

It was during one such windy evening on October 8, 2017 that a small fire ignited near the town of Calistoga, a city of approximately 5000 in Napa County. The state had effected a 'red flag warning' which alerts the public to heightened fire hazard conditions. Warm air at 32 °C combined with strong winds with peak gusts of 175 km/h. Weather stations in the hills around Santa Rosa recorded windspeed exceeding the ninety-ninth percentile as well as relative humidity below the second percentile (Nauslar et al. 2018). At the 9:44 pm local time, a resident of Calistoga reported a fire in the vicinity of Tubbs Road. Within six hours of the report, numerous fires in the region had grown into major conflagrations, collectively termed the LNU Complex (Fig. 3.1). The Tubbs fire, while not the largest of these, was the most destructive. It moved out of the WUI into urban Santa Rosa and surrounding communities.

Embers carried by strong winds ignited cascading spot fires that complicated rescue efforts by making it impossible to track the extent of the fire during the period of its most rapid expansion overnight. The fire spread uncontrolled during the night and reached the city limits of Santa Rosa by 1 am on October 9. Although

**Fig. 3.1** Central LNU Complex fires in Sonoma County (Author: Sharygin, cartography by Karácsonyi)

**Table 3.1** Characteristics of Sonoma County, Santa Rosa City and Tubbs fire perimeter

it was not fully contained until October 31, the urban destruction caused by the fire peaked within 24 h before winds died down. The Tubbs fire eventually burned almost 15,000 ha and destroyed 5636 structures, of which 4651 were residential. Collectively, the LNU Complex fires consumed more than 5000 housing units in Sonoma, Napa, and Solano counties (Hawks et al. 2017).

The following analysis focuses on impacts in Sonoma County, where the Tubbs fire displaced the greatest number of residents. The city of Santa Rosa lost 3081 housing units, representing approximately 5% of the city's housing stock (CDOF 2018). The city was already facing a housing shortage before the fire: with an overall vacancy rate of just 4.2% in 2017 (1.6% vacancy for rental units), and with 6.5% of housing units defined as 'overcrowded' (more than one resident per room).<sup>1</sup> Table 3.1 provides additional characteristics of Sonoma County, the city of Santa Rosa, and the fire-devastated areas.

The census block groups affected by the Tubbs fire had fewer renters as a share of households and higher average income. Households in the fire zone were also more likely to have at least one person in the household over the age of sixty-four, but the difference in the share of households with children was not found to be statistically significant.

### **3.3 Estimating Population Impacts From Housing Data**

### *3.3.1 Role of Housing in Population Estimates*

This section will investigate ways in which the statistics of destruction presented in the previous section could be translated to population and migration data necessary to plan a recovery effort. The State of California Demographic Research Unit produces

<sup>1</sup>U.S. Census Bureau; ACS 2017 5-year SF, table DP04. Retrieved 1 April 2019 from https://factfi nder.census.gov.

population estimates for July and January of each year. The methods of accounting for population change include housing data that enters into the calculation in several ways. Annual estimates for January 1 are produced via complimentary top-down and bottom-up estimation steps. The headline state population is estimated using a cohort component method (Swanson and Tayman 2012), in which the total population is determined by the last known population2 accounting for births, deaths, and migration. Net migration is composited from different datasets for different age groups that include school enrollment; tax returns, driver's licenses, and immigration data; and pension and health insurance data.