Scenarios andDecision Support Systems

Monika ZurekFAO, Rome

Greg KikerUniversity of Florida

GECAFS Caribbean Meeting, 30 Aug 05

Overview of the talk

Looking into the future

What are scenarios? Why use scenarios?

Decision Support Systems

The GECAFS scenarios component

Looking into the future

Out of curiosity

For scientific exploration

For decision-making

Decisions are based on expected outcomes and the

trade-offs they imply Decisions involve uncertainty about how the future will

unfold

For planning purposes/strategic planning exercise

Sources of Uncertainty when thinking about the Future

Ignorance

Understanding is limited

SurpriseThe unexpected and the novel can alter directions

VolitionHuman choice matters

Source: P. Raskin

Methods for looking into the future

Predictions are seen by the public and decision makers as things that will happen no matter what they do.

Forecast is the best estimate from a particular method, model, or individual.

Projections are heavily dependent on assumptions about drivers and boundary conditions; they often assume that these will not change. Projections lead to "if this, then that" statements.

Scenarios……

Cau

salit

y

Uncertainty (data availability)

Projection

Scenarios, predictions & projections?

What if?

Scenarios

The probability that …

PredictionF

acts

low high

unknown

known

Source: modified after R. Leemans 2003

Cau

salit

y

Uncertainty (data availability)

Projection

Scenarios, predictions & projections?

What if?

Scenarios

The probability that …

Prediction

The probability that …

PredictionF

acts

low high

unknown

known

Source: modified after R. Leemans 2003

Scenario Definitions

Plausible stories about how the future might unfold from existing patterns, new factors and alternative human choices. The stories can be told in the language of both words and numbers (Raskin, in press).

Plausible descriptions of how the future may develop, based on a coherent and internally consistent set of assumptions about key relationships and driving forces (Nakicenovic 2000).

A tool for ordering one’s perceptions about alternative future environments in which one’s decision might be played out (Schwartz 1996).

Plausible alternative futures, each an example of what might happen under particular assumptions (MA).

Why use scenarios?

Purpose of scenarios:

Information dissemination Scientific exploration Decision-making tool

Understanding all factors influencing the future Robust strategies that work under different worlds

Different process of stakeholder involvement in scenario development

Understanding and communicating the main assumptions on which people base their notion of the future

‚Good‘ scenarios should ...

... be plausible (or ‘not implausible‘)

... be internally consistent and coherent

... be constructed with rigour, detail & creativity

... meet the goals of scenario exercise!!!

Decision Support Systems

Many definitions, many visions, many versions…

DSS Integrate Tools Models Databases Visualization (GIS, graphics, charts…) Decision analysis (MCDA, trade-off analysis,

linear programming)

Spatial Maps of Ecosystem Indicators

User-Defined “Slow and Fast”

Time Steps Management Options

“Warning Lights”

Tabbed panes with several time series charts

Mouse-driven Chart and Text

Display

Reset Button

Example DSS: QnD System

Challenges in Building DSS

DSS almost always focus on one sector’s (or discipline’s) tools and concepts

Model integration is difficult and technically challenging

Not helpful in unearthing assumptions Transparency versus Ease of Use Integration with scenario planning -

“More gaps than links”

CARSEA Scenarios • Neo-Plantation Economy• Quantity Over Quality• Growing Asymmetries• Diversify Together

Tourist visits, foreign investment, external prices, etc.

Climate Scenarios • Precipitation• Hurricane Intensity/ Frequency• Sea Level Rise

QnD:Jamaica Version 0.0

• Stochastic relationships• Time series values• Incremental change

Socio-Economic Drivers

Climatic Drivers QnD Scenarios

• Neo-Plantation with mild Climate Change• Neo-Plantation with intense Climate Change• Etc…

GECAFS – research focus

1. Classifying and characterizing the major food systems existing today for GEC studies,

2. Investigating the vulnerability of existing food systems to GEC and its consequences for different parts of society,

3. Sketching plausible future changes in environmental and socioeconomic conditions that will effect food systems,

4. Based on the analysis of plausible futures, devising decision support systems for the formulation of diverse policy-instruments to adapt global food system to GEC.

Scenarios Component Research Questions

What are plausible future changes in environmental and socio-economic conditions that will affect food systems?

What elements of global scenarios are most important for regional-level food system analyses?

How best can global scenarios be linked to the regional scale in order to capture regional-level factors relevant to food systems?

Linking global and regional scenario exercises

Global Scenarios

IGP CAR SAF

Preparatory phaseFeedback

Regional GECAFS Scenarios