IWRM as a Tool for Adaptation to Climate

Change

Dealing with uncertainties

Goal and objectives of the session

At the end of this session, participants will be familiar with the uncertainties involved in:• Predicting impacts of climate change• Adapting to the predicted impacts of

climate change.

Uncertainties

One thing is certain:Nothing is certain

In this session: Uncertainty and climate change How to deal with uncertainties Types of uncertainties Adaptation to climate change under

uncertainty:• Prediction-oriented approaches• Resilience-oriented approaches.

Climate change

Changes in temperature and precipitation characterised by uncertainties regarding:

•magnitude

•timing

•spatial distribution

As well as uncertainties with respect to vulnerabilities.

Feedbacks increasing uncertainties

Melting of ice/snow > reduced reflection sun’s radiation > increased heating

Thawing permafrost > release CO2 and CH4 > accelerating global warming

Higher land and ocean temperatures: reduced uptake of atmospheric CO2.

Uncertainties in environmental management (Ravetz, 2005)

Increasingly dealing with situations where facts are uncertain, values in dispute, stakes high and decisions urgent

Weighing risks is a political task.

Uncertainties in water management

Uncertainty, variability and risk most important consequences of climate change

Climate change projections inconsistent and/or inaccurate at regional/local scales

Stationarity in weather and water systems not longer reliable basis for planning.

Experience from the past is no longer a reliable guide for the future.

Challenges in water management

Improve predictions (temporal/spatial scales required by water managers)

Collaboration/communication between climate and water resources management community

Adaptive management: adaptive and flexible approaches to improve coping with uncertain developments vs finding optimum solutions

> Institutional flexibility and a central role for stakeholders.

Typology of uncertainties: From ‘knowing for certain’ to ‘unknown’

Statistical:• Range with probability, chances, probabilities• Assuming underlying models are adequate, data

representative

Scenario:• Ranges of possible outcomes: ‘What if?’

Recognized:• Present, but can not be estimated (chaos, unknown processes)• No scientific consensus, e.g. accelerated sea level rise, shut-

down thermohaline ocean circulation.

Adaptation to CC under uncertainty

Prediction-oriented: Characterising, reducing, managing and

communicating uncertainty Increasing sophistication of modelling tools

and techniques.

Resilience-oriented: Uncertainties can not be reduced Learning from the past.

Prediction-oriented approaches

IPCC approach: Uncertain information by using CC scenarios

as drivers for impacts from which adaptation strategies are developed.

Risk approaches: Identify, evaluate, select and implement

actions to reduce risks (probability x consequences).

Frameworks for risk approaches (Dessai and van der Sluijs, 2007)

1. Identify key climatic variables2. Create scenarios/ranges for these variables3. Sensitivity analysis between CC and

impacts4. Identify impact thresholds5. Carry out risk analysis6. Evaluate risk and identify feedbacks7. Consult stakeholders, analyse proposed

adaptations, recommend planned adaptation options

Frameworks for risk approaches -2- (ten Brinke et al., 2008)

Risk management cycle/safety chain

Risk management

Pro-action

Eliminating structural causes of accidents and disasters to prevent them from happening in the first place (e.g. building restrictions in flood-prone areas)

Prevention

Taking measures beforehand that aim to prevent accidents and disasters, and limit the consequence in case such events do occur (e.g. building dykes)

Crisis management

Preparation

Taking measures to ensure sufficient preparation to deal with accidents and disasters in case they happen (e.g. contingency planning)

ResponseActually dealing with accidents and disasters (e.g. response teams)

Recovery

All activities that lead to rapid recovery from the consequences of accidents and disasters, and ensuring that all those affected can return to the ‘normal’ situation and recover their equilibrium.

Frameworks for risk approaches -3- (PLANAT)

Frameworks for risk approaches -4- (Sullivan and Meigh, 2005)

Resilience-oriented approaches (Dessai and van der Sluijs, 2007)