Presentation on theme: "Elements of Risk Analysis – Hazard and Vulnerability"— Presentation transcript:
1Elements of Risk Analysis – Hazard and Vulnerability Session 2Dr. Bijan KhazaiRisk AnalysisFundamentals of Risk Analysis11
2Learning Objectives Learn Understand The basic elements and processes of hazard analysis.The basic dimensions and elements in vulnerability analysis.The concepts of multi-hazard, exposure, susceptibility and resilience.UnderstandSpatial, dimensional and temporal components of hazard analysis.Progression of vulnerability associated with root causes, dynamic pressures, and unsafe conditions.Scales, sectors and components for vulnerability analysis.Use of indicators in vulnerability analysis.Coupling and interaction between hazard and vulnerability and the dependency of vulnerability on hazard.
3Hazard AnalysisHazard analysis describes and assesses the probability of occurrence of an extreme natural event at a specific place, at a specific time, and with specific intensity and duration for a vulnerable population.Where? How Big? How Often?Output: Severity of event by locationThis map shows relative shaking hazards in the United States and Puerto Rico. During a 50-year time period, the probability of strong shaking increases from very low (white), to moderate (light blue, green, and yellow), to high (orange, pink, and red). Blue dots are past earthquakes.Map not to scale. Source: USGS
4Where, How Big, How Often?spatialanalysisWhere are the areas which are potentially threatened?Analyze extent of impacted area1How bad can it get? What are the dimensions?Analyze local characteristicsWith what intensity and force do hazards occur?On what scale to the hazards occur?dimensionalanalysis2When and how often are future hazards to be expected?Analyze frequency and duration of the hazard eventIntervals (or cycles) of recurrencetemporalanalysis3
5Multi-hazard Analysis Analysis of only single hazards in an area might lead to a misjudgement of the „all hazards“ risks for these areas.Indexing can be one way of combining different hazards in one map.Hazards may be weighted equally or weights can be assigned based on the frequency of each hazard.Comparisons between the impact of different natural hazards on a population are more correctly performed by examining risk rather than hazard indicators.
6VulnerabilityParadox: Measuring vulnerability without precisely defining it!“Vulnerability defined as conditions determined by physical, social, economic, and environmental factors or processes, which increase the susceptibility of a community to the impact of hazards.” (UNISDR, 2004)Multi-structures of VulnerabilityExposure/ValueFragility/SusceptibilityCoping Capacity/Resilience
7Progression of Vulnerability THE PROGRESS OF VULNERABILITY123ROOT CAUSESDYNAMICPRESSURESUNSAFECONDITIONSHAZARDSPhysical Environment:Dangerous LocationsUnprotected buildings and infrastructureEconomy:Livelihoods at riskLow income levelSocial Relations:Populations at riskLack of solidarityPublic actions and Institutions:Lack of disaster preparednessLack of:Legal frameworksInstitutionsTrainingAppropriate skillsLocal InvestmentsPress FreedomEthical Standards in public lifeEarthquakeWind storms(cyclone/hurricane/Typhoon)FloodingVolcanic eruptionLandslidesDroughtVirus and pestsLimited Access to:PowerStructuresResourcesDisasterIdeologies:Political SystemsEconomic SystemsMacro ForcesRapid Population changeRapid UrbanizationSource: Blaike et al. (1996)
8Vulnerability Intervention A Vulnerability FrameworkHAZARDHazard InterventionInternational/NationalSub-nationalLocalVulnerability InterventionVULNERABILITYSUSCEPTIBILITYand FRAGILITYLACK OFRESILIENCEExposureReductionFragility /SusceptibilityResilienceImprovementEXPOSUREPhysicalEcologicalSocialEconomicCulturalInstitutionalCapacity toanticipateSpatial/TemporalCapacity tocopeCapacity torecoverAdjusted from MOVE (2009)
9ResilienceResilience is the capacity of an individual, community, organization, city, nation to respond, cope and recover from a disaster.Resilience in physical and social systems can be seen as having four infrastructural qualities:Robustness: the inherent strength or resistance in a system to withstand external demands without degradation or loss of functionality;Redundancy: system properties that allow for alternate options, choices, and substitutions under stress;Resourcefulness: the capacity to mobilize needed resources and services in emergencies; andRapidity: the speed with which disruption can be overcome and safety, services, and financial stability restored.
10Vulnerability Dependency on Hazard Degree of Vulnerability of an infrastructure, a community, a society or a process should be related to the magnitude of the hazard in question through fragility curves (or fragility functions).MaizeSorghum
11Scales, Sectors and Components of Vulnerability “fractal” nature of Vulnerability“Ministry of Education”“School District”“School Principal”Source: Villagrán, (2001)
12Vulnerability Analysis - Indicators Many aspects of vulnerability cannot be directly measured or observed, though they can be described.Indicators have been used broadly in economic, social and environmental analysis of vulnerability.Vulnerability indicators should provide information regarding the susceptibility, coping capacity and resilience of a system.Below is a mathematical description of risk as a function of the nature of a hazard and the vulnerability to that hazard..
13A Social Vulnerability Index ThemeFragility Factors (-)Resilience Factors (+)Social FragilityHow do personal attributes and living situations affect vulnerability?How do finances contribute to recovery?Coping CapacityHow do social networks affect vulnerability?How does access to services affect vulnerability?ConceptualFramework1Family Structure2Poverty3Unemployment4Disability5Home/Land Ownership1Social Networks2Risk Perception3Risk Mitigation4Community Preparedness5MobilityQuantitative IndicatorsSocial Vulnerability IndexSource: MIS model , 2009