UNCERTAINTY TREATMENT IN INTEGRATED ASSESSMENT MODELLING

Lessons learned from previous workshops

Dr. Marjolein B.A. van AsseltInternational Centre for Integrative Studies (ICIS)

Maastricht UniversityThe Netherlands

Lecture at workshop UN/ECE Task Forceon Integrated Assessment Modelling

January 24, 2002

CONTENTS

• History of IA modelling and uncertainty

• EFIEA workshop on Uncertainty

• ESF-TERM II workshop on Dealing with uncertainty in environmental management

• RIVM expert workshop on Uncertainty ‘leidraad’

1970s

1980s

1990s

2002

Club of Rome;1st generation integrated

computer simulation models

Energy-environmentmodels

First IA models: RAINS, IMAGE, DICE

A wealth of IA models (climate change,

acidification, global change)

O’Neill;Importance of uncertainty in environmental modelling

PhD Hettelingh: uncertainty in regional IAMsJanssen et al. RIVM report Uncertainty & Sensitivity analysis

ICAM (probability based IAM)TARGETS, QUEST (perspective-based uncertainty analysis)

PhD van der Sluijs: Uncertainty & IAMsRefelections on IA uncertainty identified as critical topic

July ’99: EFIEA workshop on uncertaintyNov ’00: ESF-TERM II workshop on Dealing with uncertainty

Oct ’01: RIVM expert workshop uncertainty

Among others: Bailey et al., ’96, Risbey et al., ’96, Rotmans and van Asselt, ’96, Morgan and Dowlatabadi, ’96, Parson, ’96, Schneider, ’97, Ravetz, ’97, Jäger, ’98, Rotmans and Dowlatabadi, ‘98

Club of Rome;1st generation integrated

computer simulation models

Energy-environmentmodels

First IA models: RAINS, IMAGE, DICE

A wealth of IA models (climate change,

acidification, global change)

O’Neill;Importance of uncertainty in environmental modelling

PhD Hettelingh: uncertainty in regional IAMsJanssen et al. RIVM report Uncertainty & Sensitivity analysis

ICAM (probability based IAM)TARGETS, QUEST (perspective-based uncertainty analysis)

PhD van der Sluijs: Uncertainty & IAMsRefelections on IA uncertainty identified as critical topic

July ’99: EFIEA workshop on uncertaintyNov ’00: ESF-TERM II workshop on Dealing with uncertainty

Oct ’01: RIVM expert workshop uncertainty

16th century

17th century

18th century

19th century

1905

1960

2002

Descartes

Enlightenment: reason and objectivity as key values

Dominance of positivism: the search for and prediction of empirical regularities to make universal, true statements / perfect, complete knowledge; uncertainty is unscientific

Einstein’s new physic: relativism instead of absolutism

Heisenberg’s uncertainty principle

“sceptical crisis”

post-modernism: truth and certainty are illusions social constructivism: knowledge is constructed

uncomfortable splits: acceptance of uncertainty positivist practice

ongoing search for uncertainty management

EFIEA workshop on Uncertainty

• European Forum on Integrated Environmental Assessment www.vu.nl/ivm/efiea

• 10-18 July 1999

• Baden bei Wien, Austria

• Organisors Jill Jäger and Carlo Jaeger 40 participants

EFIEA workshop on Uncertaintytopics

• Uncertainty and climate change• Integrated Water Assessment• Uncertainty in Economic analysis• Uncertainty in IA modelling• Uncertainty in participatory IA• Expert elicitation• IA focus groups• Ad hoc groups on No regret policies and on

interface users-producers Integrated Assessments

EFIEA workshop on Uncertainty

• Report edited by Jill Jaeger:– No consensus report– Broad collection of ideas

• My (subjective) evaluation:– Community-wide recognition for uncertainty as

important topic in IA (milestone)– Model(lers)-oriented– Rich and useful discussions but not focussed on

uncertainty, but more broadly on IA

For example, Integrated water assessment; participation; cultural differences; changing role of science in society; IPCC; integration of macro-economic with bottom-up technological models

EFIEA workshop on Uncertaintyconcluding statements

• “There are different notions of what uncertainty is and means. At least there is a distinction between uncertainties as viewed by decision-makers, uncertainties in the real world and model uncertainties.”

• “It is important to assess new methods to handle unquantifiable uncertainties”

• “There is not one method that suffices in doing uncertainty analysis for IAM”

• “Stories behind the numbers ease the discussion of uncertainties”• “Participatory processes may be used to evaluate the uncertainty about

particular outcomes / as tool for improving our understanding of disagreements”

EFIEA workshop on Uncertaintysuggestions

• Peer review system for validating IAMs (validation protocols, testing procedures)

• Competition within and between ‘families’ of models

• Need for intermediate/communication interfaces

• Assessment through series of what-if analyses / multiple scenarios

EFIEA workshop on UncertaintyIdentified research questions & themes

• Uncertainty and disagreement/dissent/value diversity

• How do decision-makers deal with uncertainty? What do they need to know to be able to act?

• Assessment of extremes/extreme events, outliers, poorly known/small probability - high consequence scenarios and cumulation of uncertainty

• How to do expert elicitation in a sound way?

• Communication of uncertainty (both inside and outside scientific community)

• Classification/taxonomy of uncertainty

“Not in order to produce the ultimate typology of

uncertainties, but to clarify the differences in terminology”

Workshop “Dealing with uncertainty in environmental management”

• European Science Foundation TERM II programme

• 1-3 November 2000

• Maastricht, the Netherlands

• Organised by Marjolein van Asselt & Rob Maas; hosted by ICIS & RIVM

40 participants

ESF workshop on Dealing with uncertaintytopics

• Institutional and policy dimensions• Uncertainty in integrated assessment

cases transboundary air pollution, RIVM’s environmental outlooks, water

• Pluralistic uncertainty management (PRIMA)• Agenda-setting for social-scientific research

Uncertainty in relation to perception and social constructionUncertainty is more than statistics/mathematical artefact

• Binder with abstracts, papers and slides and internal report for ESF

• My (subjective) evaluation:– broad interest in uncertainty management– box of Pandora feeling– primarily a ‘consuming’ audience– more uncertainty awareness than uncertainty

management workshop

ESF workshop on Dealing with uncertainty

“I want to further explore uncertainty”“Uncertainty has become more than just a

mythical concept”“I learned to see uncertainty as an opportunity

and challenge, and less as a risk”“ I used to be afraid of pluralism”

ESF workshop on Dealing with uncertainty Identified research questions & themes

• criteria for uncertainty management (in what cases does uncertainty management add value?)

• institutional factors, contexts and arrangements• uncertainty i.r.t. type of policy problems /phases in policy life cycle • uncertainty about policy responses and decision-making processes• uncertainty requires permanent learning; how to facilitate learning processes

(continuous dialogue/interaction scientists-decisionmakers)? • willingness to accept uncertain outcomes• pluralistic uncertainty managent - convergence• ambiguity/ debatable constructed certainties / diverging certainties• communication of uncertainty• responsibility of scientists, codes of ethics

ESF workshop on Dealing with uncertainty Observations

• “Uncertainty management is not possible without a clear problem definition”

• “Mismatch: Scientists address a subset of uncertainties policy makers need, and at the same time policy makers don’t need the degree of precision scientists are aiming at”

ESF workshop on Dealing with uncertainty suggestions

• Strengthen communication between natural sciences and social sciences on uncertainty

• Including more perspectives and assumptions force politicians to discuss what they want to take responsibility for

• (Type of) uncertainty as filter for selecting relevant stakeholders

• Fields we can learn from: risk & hazard management, game theory, discourse analysis

Expert workshop on uncertainty ‘leidraad’

• RIVM

• 25 October 2001

• Utrecht, the Netherlands

• Organised by Jeroen van der Sluijs (Utrecht University)

15 experts

Expert workshop on uncertainty ‘leidraad’ topics

• Uncertainty and problem framing• Typologies• Quantitative methods• Qualitative methods• Interplay science and policy / post-normal science

• “Leidraad” see Presentation Jeroen van der Sluijs (tomorrow); paper in preparation Harremous et al.

• My (subjective) evaluation:– high-level constructive discussions and collective

thinking among variety of uncertainty experts

– shared recognition of the need for interdisciplinary and inter-institute teamwork

– agreement to disagree (typology, terminology)

Expert workshop on uncertainty ‘leidraad’

EFIEA workshop (‘99):milestone in putting uncertainty on IA agenda

ESF workshop (‘00):uncertainty awareness & broader recognition

EFIEA workshop (‘99):milestone in putting uncertainty on IA agenda

ESF workshop (‘00):uncertainty awareness & broader recognition

Expert workshop (‘01):teamwork towards uncertainty management

EFIEA workshop (‘99):milestone in putting uncertainty on IA agenda

ESF workshop (‘00):uncertainty awareness & broader recognition

Expert workshop (‘01):teamwork towards uncertainty management

UN/ECE Task force workshop (‘02):???????

EFIEA workshop (‘99):milestone in putting uncertainty on IA agenda