lecture overview - adpc overview risk assessment & management ... consequently, the...

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Lecture Overview

Risk assessment & managementDefinitionsElements at risk• Classification• Types of losses• Building & facilities subclasses• Data sources

Vulnerability• Social science approaches to vulnerability• Natural science approaches to vulnerability• Effects on vulnerabilitity• Conclusions & perspectives

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Risk assessment & management (1/3)

Probab ility o f landslid ing

Triggering factors

Landslide inventory

P reparato ry factors

H azard assessm ent

R unout behavior Land use

E lem ents a t risk

V ulnerab ility assessm ent

R isk assessm ent

R isk m anagem ent

C ost-benefit ana lys is Dai et al. (2002)

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Risk AnalysisNatural Science

Risk EvaluationSocial Science

Risk ManagementInterdisciplinary

Hollenstein, 1997

Risk = f (Hazard, Elements at risk, Vulnerability)Varnes, 1984

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adopted from Hollenstein, 1997 & Kienholz, 1995

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Risk Management

Glade & Crozier, 2005

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Definitions (1/2)

Hazard (I): a potentially damaging process or situation, e.g. a landslide of sufficient size, depth, or displacement to cause damage or disruption.

Hazard (II, H): the probability of a potentially damaging event of a given magnitude occurring in a unit of time.

Elements at risk (E): all valued attributes threatened by the hazard and may include structures, land resources, social and physical infrastructure, productive and non-productive activities, environmental qualities, life and physical and mental wellbeing.

based on Crozier & Glade, 2004 ???

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Definitions (2/2)

Vulnerability (V): the expected degree of loss experienced by theelements at risk for a given magnitude of hazard.

Risk (R): a measure of the probability and severity of loss to theelements at risk, usually expressed for a unit area, object, oractivity, over a specified period of time. R = H x E x V

Acceptable risk: a level of risk that a given society is prepared to accept because of the marginal cost of any further risk reduction. Risk management may aim to reduce all risks to this level.

based on Crozier & Glade, 2004 ???

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Elements at risk

Classification of elements at riskTypes of losses• Human/Social/Economic• Primary/Secondary

Building and facilities• Main subclasses

Data sources• Remote sensing• Cadastres• Censuses

Adopted from Montoya wy

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Classification of elements at risk

Building & facilitiesPopulationThe environmentProductionEconomic activities


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Types of losses

•Losses borne by theinsurance industryweakening the insurancemarket and increasingpremiums•Loss of markets and tradeopportunities through shorttermbusiness interruption•Loss of confidence byinvestors, withdrawal ofinvestment•Capital costs of repair

•Progressivedeterioration ofdamaged buildingsand infrastructurewhich are notrepaired

•Disease•Permanent disability•Psychological impact•Loss of social cohesion dueto disruption of community•Political unrest (govt.response is perceived asinadequate)

Secondary Effect

•Interruption of businessdue to damage to buildingsand infrastructure•Loss of productiveworkforce through fatalities,injuries and relief efforts•Capital costs of responseand relief

Ground deformationor loss of groundquality

Structural damage or collapse to buildingsand infrastructure

Non-structuraldamage and damageto contents

FatalitiesInjuriesLoss of income or

employment opportunities

•Homelessness

Primary Effect

EconomicPhysicalHuman - social

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Buildings & Facilities

General building stockEssential facilitiesHigh potential loss facilitiesTransportation systemsLifeline utility systems


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Construction• Structure

• Building material• Structural type• Height (Basement?)

• ContentsOccupancy (Land use)

Buildings & Facilities – General building stock (1/4)


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Occupancy (Land use)• Residential

• Single family• Multi-family• Temporary-lodging• Mobile home• Institutional• Nursing


IKONOS, Denver, USA


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Occupancy (Land use)• Industrial

• heavy• light• food/drugs/chemicals• metals/mineral processing• high technology


IKONOS, London, UK


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Occupancy (Land use)• Commercial/Institutional

• retail trade• wholesale trade• banks• hospital• medical office/clinic


IKONOS, Singapore


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Facilities that provide services to the community and should be functional after a disaster• Police stations• Hospitals• Fire stations• Schools

Buildings & Facilities – Essential facilities (1/2)


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Hospitals• Vital role in the preservation of life and health in

disaster situations• Essential but also highly vulnerable

• Complexity• Small rooms/long corridors• High occupancy 24 hours/day• Hazardous material

Buildings & Facilities – Essential facilities (2/2)


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Population

Most important characteristics• Children • Elderly population• low-income

Not fixed to the groundActivity based location• At home (18:00 – 08:30)• At work (09:00 – 17:30)• Commuting hours (08:30 – 09:00; 17:30 – 18:00)=> Not 1 scenario but at least 2

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Data sources for elements at risk mapping

Satellite data• Many objects can be distinguished• Satisfactory for regional disaster management

But: A detailed risk assessment have to complement with or use:

CadastresCensusesLanduse mapsField survey


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Vulnerability - Basic Issues

Vulnerability relates to the consequences, or the results of an impact of a natural force, and not to the natural process or force itself (Lewis 1999).

Lewis, 1999

Consequences are generally measured in terms of damage and losses, either on a metric scale in terms of a given currency, or on a non-numerical scale based on social values or perceptions and evaluations.

Social Science Approach Natural Science Approach

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Types of vulnerability

NaturalEcologicalTechnicalEconomincalStructural

SocialPoliticalIdeologicalCulturalEducative

Wilches-Chaux, 1992

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Social Science Approaches: Vulnerability 1/7

Consequently, the “…so-called natural disasters are primarily the products of political economies and not the natural hazards themselves…” (Mileti 1999:120).

Any natural hazard, natural risk, and consequentlyany form of „natural“ disaster is caused byhumans (Geipel 1992).

Weichselgartner (2001:85) argues, “…natural disasters are socially constructed…”

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Social Science Approaches: Vulnerability 2/7Any “natural” disaster is thus the result of bad or false adaption to nature (Dombrowski 2001).

Concept of ‘voluntary’ and ‘involuntary’ activities within risk assessments (Adams 1998; Starr 1969). The living in a hazardous area is more voluntary for the rich (Smith 2001).

Chambers (1989)(1989) refers to both refers to both internal and external internal and external dimensionsdimensions affecting vulnerability.affecting vulnerability.

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Pohl (1998) states that if a natural event is endangering people or property, the event will be perceived as a hazard. If the person – or society –that is threatened or endangered can make decisions and react to potential process occurrence, the hazard becomes a risk. Consequently, if an individual or a society has no opportunity to make decisions, the natural event is “just” a hazard, not a risk (Pohl & Geipel 2002).


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Smith (2001:6) notes that “…risk means different things to different people because each person holds a unique view of the environment…” and gives therefore a vague definition only.

As early as 1956, Simon “… argued that perception is a filter through which the decision maker views the ‘objective’ environment ant its hazards…” (in Smith 2001:67).


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Chambers (1989): “…vulnerability…is not the same as poverty. It means not lack of want, but defenceless and an inability to cope with risk, shocks and stress”.

BlaikieBlaikie et al.et al. (1994: 9)(1994: 9) define vulnerability as define vulnerability as “…the characteristics of a person or a group in “…the characteristics of a person or a group in terms of their capacity to anticipate, cope with, terms of their capacity to anticipate, cope with, resist, and recover from the impact of a natural resist, and recover from the impact of a natural hazard.”hazard.”

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Vulnerability is closely correlated with socio-economic position and depends on class, caste, ethnicity, gender, disability, age, education and seniority (Blaikie et al. 1994; Hewitt 1997).Vulnerability is determined by factors closely related to conditions, whether or not people and their environment are able to withstand or copewith a natural disaster (Hewitt 1997; Smith 2001).

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“.... not only are people different, but they are changing continuously, both as individuals and as groups. This constant change within the human system ..... interacts with the physical system to make hazard, exposure, and vulnerability all quite dynamic” (Mileti 1999: 119).“.... vulnerability reduction itself would be socially and environmentally sustainable development .…” (Lewis 1999: 42).


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Natural Science Approach: Vulnerability 1/2

A comprehensive natural risk assessment includes risk analysis, risk perception and evaluation, and risk management (e.g. Hollenstein 1997).

The product of Elements at Risk and Vulnerabilityis also often expressed as consequences (e.g. Wu et al. 1996), but should not to be confused with exposure (Alexander 2000).

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Natural Science Approach: Vulnerability 2/2

Vulnerability is important in the determination of the consequence and refers to the degree of loss of a given element at risk, or set of elements at risk resulting from event occurrence of a given magnitude (Newman and Strojan 1998).

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Vulnerability: Diverse Effects

Vulnerability of different elements at risk varies for similar processes (Fell 1994: 263)

Temporal probability for a person of being present during the landslide event is variable.Different groups of humans have different coping potentials.Early warning system affects the vulnerability of people.Spatial probability of landslide occurrence influences vulnerability.

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Vulnerability: Conclusions

No unique and simple method is currently available.Vulnerabilities of given elements at risk towards a specific type and magnitude of process are frequently missing.Vulnerability is commonly based on estimates and refer often to examples from other regions, or even other processes.Vulnerability is not static – it is changing!!

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Vulnerability: Future Research

Details on elements at risk and their specific vulnerability to the respective magnitude of event. Vulnerability curves. Advanced vulnerability modelling approaches for various natural hazards (e.g. Hollenstein et al. 2002; Melching 1999)

Calculation of vulnerability maps - instead of ‘risk’maps (e.g. Weichselgartner 2001).

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Hazard, Vulnerability & Risk …

Natural hazard analysis should move towards natural risk analysis (e.g. Glade et al. 2005).Natural risk calculations are crucial – estimates. Natural risk assessment should also include the investigation of the communication.Natural risk analysis commonly only available for local and regional scales, smaller scale studies are rare (e.g. for landslides Dikau & Glade 2003).Risk as a dynamic approach (Hufschmidt et al. 2005)

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ReferncesAdams J. 1998: Risk. London, UCL Press.Alexander, D.E. 2000: Confronting catastrophe. New York: Oxford University Press.Blaikie, P., Cannon, T., Davis, I. and Wisner, B. 1994: At risk - Natural hazards, people's vulnerability, and disasters. London: Routledge.Chambers R. 1989: Vulnerability, coping and policy. IDS Bulletin 20, 1-7.Dikau, R. and Glade, T. 2003: Nationale Gefahrenhinweiskarte gravitativerMassenbewegungen. In Liedtke, H., Mäusbacher, R. and Schmidt, K.-H., editors, Relief, Boden und Wasser, Heidelberg: Spektrum Akademischer Verlag, 98-99.Dombrowsky W.R. (2001): Die globale Dimension von Katastrophen. In – Plate, E.J. und B. Merz (Hrsg.): Naturkatastrophen . Ursachen, Auswirkungen, Vorsorge, 229-246Fell, R. 1994: Landslide risk assessment and acceptable risk. Canadian Geotechnical Journal 31, 261-272.Geipel, R. 1992: Naturrisiken: Katastrophenbewältigung im sozialem Umfeld. Darmstadt: Wiss. Buchges.

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ReferncesGlade, T. and Crozier, M.J. 2005: A review of scale dependency in landslide hazard and risk analysis. In Glade, T., Anderson, M.G. and Crozier, M.J., editors, Landslide hazard and risk, Chichester: Wiley, 75-138.Glade, T., Anderson, M.G. and Crozier, M.J. 2005: Preface. In Glade, T., Anderson, M.G. and Crozier, M.J., editors, Landslide hazard and risk,Chichester: Wiley, xi-xx.Hewitt, K. 1997: Regions of risk. A geographical introduction to disasters. Essex: Addison Wesley Longman Limited.Hollenstein, K. 1997: Analyse, Bewertung und Management von Naturrisiken. Zürich: vdf Hochschulverlag AG, ETH Zürich.Hollenstein, K., Bieri, O. and Stückelberger, J. 2002: Modellierung derVulnerability von Schadensobjekten gegenüber Naturgefahrenprozessen. Bern: Bundesamt für Umwelt Wald und Landschaft (BUWAL), 116.Hufschmidt, G., Crozier, M.J. and Glade, T. 2005: Evolution of landslide risk in New Zealand. In Gutiérrez, F., Gutiérrez, M., Desir, G., Guerrero, J., Lucha, P., Marín, C. and García-Ruiz, J.M., editors, 6th International Conference on Geomorphology, 7.-11. September 2005, Zaragoza, Spain, 341.

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ReferncesKienholz, H. 1995: Gefahrenbeurteilung und -bewertung - auf dem Weg zueinem Gesamtkonzept. Schweizerische Zeitschrift für Forstwesen 9, 701-725.Lewis 1999: Development in disaster-prone places - Studies of vulnerability. London: Intermediate Technology Publications Ltd.Melching, C.S. 1999: Economic aspects of vulnerability. In World Metereological Organization, editor, Comprehensive risk assessment for natural hazards, Geneva: World Metereological Organization,, 66-76.Mileti, D.S. 1999: Disasters by design - A reassessment of natural hazards in the United States. Washington, D.C.: Joseph Henry Press.Montoya, L. wy: Elements at risk. ITC-presentation.Newman, M.C. and Strojan, C.L. 1998: Risk assessment: logic and measurement. Chelesea, Michigan: Ann Arbor Press.Pohl J. & R. Geipel, 2002: Naturgefahren und Naturrisiken. GeographischeRundschau 54(1), 4-8.Pohl J. 1998: Die Wahrnehmung von Naturrisken in der "Risikogesellschaft".- In: G. Heinritz, R. Wiessner & M. Winiger (Eds.) Nachhaltigkeit als Leitbild derUmwelt- und Raumentwicklung in Europa. Stuttgart, 153-163.

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ReferncesSmith K. 2001: Environmental hazards: Assessing risk and reducing disaster. London, Routledge.Smith, K. 2001: Environmental hazards: Assessing risk and reducing disaster. London.Starr C. 1969: Social benefit versus technological risk. Science 165, 1232-1238.Varnes, D.J. 1984: Landslides hazard zonation: a review of principles and practice. Paris, France: UNESCO.Weichselgartner, J. 2001: Disaster mitigation: the concept of vulnerability revisited. Disaster Prevention and Management 10, 85-94.Wilches-Chaux, G. 1992: The global vulnerability. In Aysan, Y. and Davis, I., editors, Disasters and the small dwelling, 30-35.

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