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The Deconstruction of Volcanic Risk Case Study: Galeras, Colombia

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The Deconstruction of Volcanic Risk Case Study: Galeras, Colombia THE DECONSTRUCTION OF VOLCANIC RISK CASE STUDY: GALERAS, COLOMBIA Jessica Kate Roberts Ph.D. University of York Environment February 2015 “It would be nice if all of the data which sociologists require could be enumerated because then we could run them through IBM machines and draw charts as the economists do. However, not everything that can be counted counts, and not everything that counts can be counted” William Bruce Cameron, (1963) 2 Abstract History has shown that the combination of active volcanism and human populations can lead to devastating consequences, which at their most extreme have resulted in the collapse of entire societies. However these losses have not only been attributed to the impact of volcanic hazards but also the management strategies put in place to try to mitigate them, criticised for the detrimental long-term socio-economic impacts they have had on communities involved. General risk management theory argues that the failure of risk management strategies can be in part due to the poor risk assessment methodologies used to inform decision-making. ‘Insufficient’ or ‘inaccurate’ data is often attributed to disciplinary biases, a weakness in methodological tools and a focus on top down prescriptive approaches lacking in participation from those living with the risks in question. This thesis, acknowledging these broader debates, examines whether the way in which volcanic risk is assessed is fully representative of the complexities of the relationship between society and volcanoes. Using an empirical study of communities living on the Galeras volcano in Colombia, it compares the public experience of risk with the way in which it is interpreted and measured within Volcanology. Results of the study show that whilst previous volcanic risk assessments have been strong in their ability to capture data on volcanic hazards, assessment methods have been significantly weaker in their ability to address the threat of other non-volcanic hazards, social vulnerability and the social, economic and cultural value of the volcano environment. This thesis argues that a more sustainable approach to volcanic risk management is dependent upon risk assessments methodologies being developed that combine both the analytical frameworks of Volcanology with the experiential influences that drive the attitudes and behavior of the communities in question. TABLE OF CONTENTS ABSTRACT 3 LIST OF FIGURES 10 LIST OF TABLES 11 ACKNOWLEDGEMENTS 13 AUTHORS DECLARATION 17 CHAPTER ONE: INTRODUCTION 18 1.0 RESEARCH OUTLINE 19 1.1 RESEARCH RATIONALE 20 1.1.1 THE GLOBAL IMPACT OF NATURAL DISASTERS 20 1.1.2 THE GLOBAL IMPACT OF VOLCANIC DISASTERS 21 1.1.3 THE ROOT CAUSES OF VOLCANIC DISASTERS 23 1.1.4 THE CHALLENGE FOR REDUCING VOLCANIC RISK 25 1.1.5 THE CASE FOR USING PARTICIPATORY 28 APPROACHES IN RISK ASSESSMENT 1.2 RESEARCH AIMS AND OBJECTIVES 34 1.3 THE STRUCTURE OF THE THESIS 34 CHAPTER TWO: CHOOSING TO LIVE WITH VOLCANIC HAZARDS: 36 A LITERATURE REVIEW 2.0 INTRODUCTION 37 2.1 UNDERSTANDING THE COMPLEXITY OF SOCIAL VULNERABILITY 37 2.2 LIVING WITH ENVIRONMENTAL HAZARDS 40 2.2.1 RISK PERCEPTION 40 2.2.2 PRIORITISATION 40 2.2.3 RESILIENCE 41 2.2.4 SOCIAL CAPITAL 44 2.2.5 TRADITIONAL SOCIETIES 44 2.3 VOLCANIC COMMUNITIES 45 2.4 MOUNTAIN COMMUNITIES 49 2.4.1 SOCIAL VULNERABILITY IN MOUNTAIN COMMUNTIES 50 2.5 VOLUNTARY AND INVOLUNTARY MIGRATIONS 53 2.6 SUMMARY 54 CHAPTER THREE: METHODOLOGY 56 3.0 INTRODUCTION 57 3.1 THE CASE STUDY APPROACH 57 3.2 THE STUDY AREA 59 4 3.3 ACCESSING THE COMMUNITY 60 3.4 METHOD SELECTION AND SUBJECT SAMPLING 61 3.5 A SYNTHESIS OF VOLCANIC RISK ASSESSMENTS 66 3.5.1 METHOD 66 3.5.2 KEY THEMES EMERGING FROM THE SYNTHESIS OF VOLCANIC RISK 67 3.5.3 KEY THEMES EMERGING FROM THE SYNTHESIS OF 68 VOLCANIC VALUE 3.5.4 KEY THEMES EMERGING FROM THE 68 SYNTHESIS OF VOLCANIC HAZARD 3.5.5 KEY THEMES EMERGING FROM THE REVIEW A 70 SYNTHESIS OF VOLCANIC VULNERABILITY 3.5.6 SYNTHESIS SUMMARY 72 3.6 DEVELOPING A FRAMEWORK FOR THE INTERVIEW QUESTIONS 72 3.6.1 SELECTING QUESTIONS TO EXPLORE COMMUNITY 74 EXPERIENCE OF VALUE 3.6.2 SELECTING QUESTIONS TO EXPLORE COMMUNITY 75 EXPERIENCE OF HAZARD 3.6.3 SELECTING QUESTIONS TO EXPLORE COMMUNITY 76 EXPERIENCE OF VULNERABILITY AND RESILIENCE 3.7 THE INTERVIEW TRANSCRIPT 77 3.8 THE PILOT STUDY 80 3.9 TRANSCRIBING AND TRANSLATION 80 3.10 INTERPRETING THE DATA 81 3.11 REPORTING THE DATA 85 3.12 POSITIONALITY AND REFLEXIVITY 86 3.13 SUMMARY 89 CHAPTER FOUR: THE ECOLOGICAL AND SOCIO-ECONOMIC CONTEXT OF SOCIAL VULNERABILITY IN COLOMBIA 90 4.0 INTRODUCTION 91 4.1 CLIMATE AND RESOURCES 91 4.2 PEOPLE 92 4.3 LIVELIHOODS AND ECONOMY 93 4.4 INFRASTRUCTURE 94 4.5 SOCIAL AND ENVIRONMENTAL ISSUES 95 4.6 NATURAL HAZARDS AND RISK MANAGEMENT 98 4.7 THE CHALLENGE OF THE GALERAS CASE STUDY 101 5 4.8 SUMMARY 102 CHAPTER FIVE: DECONSTRUCTING VALUE 103 5.0 INTRODUCTION 104 5.1 THEME ONE: QUALITY OF LIFE 104 5.1.1 TRANQUILITY 107 5.1.2 COMMUNITY 108 5.1.3 SAFETY 111 5.1.4 CONTRADICTIONS WITHIN COMMUNITY PERCEPTIONS 112 5.1.4.1 WORK AND WEALTH 113 5.1.4.2 POVERTY 113 5.1.4.3 HEALTH AND FOOD PRODUCTION 115 5.1.4.4 GALERAS, FRIEND NOT FOE 116 5.1.5 SECONDARY CODING OF QUALITY OF LIFE DATA 118 5.2 THEME TWO: MOTIVATION TO RESIDE ON GALERAS 120 5.2.1 TRANQUILITY 120 5.2.2 ANCESTRY 121 5.2.3 EMPLOYMENT 123 5.2.4 SECURITY 123 5.2.5 COMMUNITY 124 5.2.6 COST OF LIVING 124 5.3 THEME THREE: INCOME SOURCES 125 5.3.1 LOCATION OF INCOME SOURCE 126 5.3.2 SECONDARY CODING OF INCOME SOURCES 127 5.3.3 RELATIVE IMPORTANCE OF INCOME SOURCES 127 5.4 THEME FOUR: LAND USE 128 5.4.1 LAND USE MOTIVATION 129 5.4.2 THE CHANGING LAND USE PROFILE 132 5.4.3 A MOSAIC LANDSCAPE OF NICHE OPPORTUNITIES 134 5.4.4 CROP PROFILE 136 5.4.5 RELATIVE IMPORTANCE OF LAND USE 139 5.4.6 ECONOMIC VALUE OF LAND USE 141 5.4.7 CULTURAL VALUE OF LAND USE 141 5.5 THEME FIVE: THE DIRECT BENEFITS OF GALERAS 143 5.5.1 WATER 144 5.5.2 VOLCANIC ASH 145 5.5.3 OPPORTUNITIES FOR TOURISM 149 5.5.4 QUALITY OF AIR 149 6 5.5.5 THE BEAUTY OF THE LANDSCAPE 149 5.5.6 FORESTRY PRODUCTS 150 5.5.7 THE CIRCUMBALAR ROAD 150 5.5.8 OTHER BENEFITS 151 5.5.8.1 SECURITY 151 5.5.8.2 A GOOD ECONOMY 152 5.5.8.3 GOOD HEALTH 152 5.5.8.4 COMMUNITY 152 5.5.8.5 ANCESTRY 152 5.5.8.6 SOCIAL SECURITY 152 5.5.8.7 COMPENSATION 152 5.5.8.8 SYMBOLIC REFERENCE 152 5.6 THEME SIX: FUTURE POTENTIAL OF THE GALERAS COMMUNITIES 153 5.6.1 AGRICULTURE 154 5.6.2 TOURISM 156 5.6.3 SMALL ENTERPRISES 158 5.6.4 WATER 158 5.6.5 THE COMMUNITY 158 5.7 THEME SEVEN: PLACES OF IMPORTANCE ON GALERAS 160 5.8 SUMMARY 163 CHAPTER SIX: DECONSTRUCTING HAZARD THROUGH THE LIVELIHOOD LENS 164 6.0 INTRODUCTION 165 6.1 HAZARDS AND THE LIVELIHOOD SYSTEM 165 6.1.1 ACCESS TO LIVELIHOOD ASSETS 2002- 2012 168 6.2 CATEGORISING HAZARDS TO LIVELIHOOD ASSETS 170 6.2.1 THE GALERAS LIVELIHOODS RISK MATRIX 179 6.2.2 MAPPING THE HAZARDSCAPE OF GALERAS 180 6.2.3 COMPARING COMMUNITY DISRUPTIONS 181 6.2.4 CASCADING HAZARDS 184 6.2.5 LOCALISED HAZARDSCAPES 186 6.3 SUMMARY 187 CHAPTER SEVEN: DECONSTRUCTING VULNERABILITY AND RESILIENCE 188 7.0 INTRODUCTION 189 7.1 IDENTIFYING INCOME AND EXPENDITURE 189 7.1.1 MONTHLY EXPENSES 191 7 7.2 IDENTIFYING NECESSITIES FOR THE FUNCTIONING OF THE GALERAS LIVELIHOOD SYSTEM 193 7.2.1 THEME ONE: EMPLOYMENT 195 7.2.2 THEME TWO: PHYSICAL HEALTH 195 7.2.3 THEME THREE: EDUCATION 196 7.2.4 THEME FOUR: FOOD 196 7.2.5 THEME FIVE: WATER 196 7.3 IDENTIFYING THREATS TO THE FUNCTIONING OF THE LIVELIHOOD SYSTEM 199 7.3.1 THEME ONE: EMPLOYMENT 201 7.3.2 THEME TWO: GOVERNANCE 202 7.3.3 THEME THREE: THE VOLCANO 203 7.3.4 THEME FOUR: WEALTH 203 7.3.5 THEME FIVE: PUBLIC SERVICES 204 7.3.6 THEME SIX: CLIMATE CHANGE 204 7.4 IDENTIFYING THE EFFECTIVE RESPONSES NEEDED TO DEAL 208 WITH DISRUPTIONS TO THE LIVELIHOOD SYSTEM 7.5 IDENTIFYING THE FUTURE POTENTIAL OF THE GALERAS 211 COMMUNITIES 7.6 REALISING THE FUTURE POTENTIAL OF THE GALERAS COMMUNITIES 212 7.7 SUMMARY 218 CHAPTER EIGHT: DISCUSSION 220 8.0 INTRODUCTION 221 8.1 DECONSTRUCTING RISK AT GALERAS 222 8.2 DECONSTRUCTING VALUE AT GALERAS 223 8.2.1 THE VALUE OF GALERAS THE LIVELIHOOD 223 SYSTEM 8.2.2 THE VALUE OF GALERAS THE MOUNTAIN 226 8.2.3 THE VALUE OF GALERAS THE ASSET 238 8.2.4 INFORMED AND RATIONAL DECISION MAKING 230 8.2.5 THE VALUE OF GALERAS FOR THE FUTURE 231 8.2.6 THE VALUE OF GALERAS THE VOLCANO ECOSYSTEM 232 8.2.7 THE VALUE OF GALERAS THE PLACE 233 8.2.8 SUMMARY OF VALUE 236 8.3 DECONSTRUCTING HAZARD AT GALERAS 237 8.3.1 THE HAZARDSCAPE OF GALERAS 238 8.3.2 HETEROGENEITY OF HAZARDS 240 8 8.3.3 DIFFERING COMMUNITY PERCEPTIONS OF RISK 241 8.3.4 SUMMARY OF HAZARD 245 8.4 DECONSTRUCTING VULNERABILITY AT GALERAS 246 8.4.1 THE GALERAS VULNERABILITY PROFILE 246 8.4.2 THE COPING CAPACITY OF THE GALERAS COMMUNITIES 249 8.4.3 THE INFLUENCE OF VOLCANIC ACTIVITY ON SOCIAL VULNERABILITY 250 8.4.4 RISK PERCEPTION AS AN INFLUENCE OF VULNERABILITY255 8.4.5 SUMMARY OF VULNERABILITY 252 8.5 RECONSTRUCTING VOLCANIC RISK ASSESSMENTS 252 8.5.1 A NEED FOR FURTHER DEVELOPMENT OF VALUE AND VULNERABILITY ASSESSMENT TOOLS 254 8.5.2 THE NEED TO PROTECT VOLCANIC CULTURES 255 8.5.3 THE NEED FOR A CULTURAL SHIFT IN VOLCANOLOGY 256 8.6 SUMMARY 257 CHAPTER NINE: CONCLUSION 258 9.0 CONCLUSIONS 259 9.1 RECOMMENDATIONS FOR FUTURE VOLCANIC RISK ASSESSMENTS 266 9.1.1 SUMMARY 267 APPENDICES 269 HOUSEHOLD INTERVIEW TRASNCRIPT 270 RESEARCH ETHICS FORM 2011 281 REFERENCES 289 9 LIST OF FIGURES FIGURE 3.1: VOLCANIC HAZARD MAP OF GALERAS 58 FIGURE 3.2: THE SIX CASE STUDY SITES 60 FIGURE 3.3: THE DATA COLLECTION METHODOLOGY 63 FIGURE 3.4: THE SUSTAINABLE LIVELIHOODS FRAMEWORK 83 FIGURE 5.1: PERCEPTIONS OF QUALITY
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