Science and Policy interface: role of integrated assessment modelling (IAM) and cost-benefit analysis (CBA)

Integrated Assessment Modelling (IAM) has been at the heart of European air quality policy development for more than two decades3. Such tools provide a useful framework for policy makers to connect the increasingly complex science dealing with multiple pollutants and multiple effects to practical and cost-effective policy. Given that the complexity of the underlying science is embedded (often deeply embedded) within the IAM, the development and use of such tools places significant responsibility on the scientific community involved.

First they need to ensure that ‘good science’ is incorporated into the model and that uncertainties in the science are made transparent and their policy relevance explored. Second, they need to ensure that the exogenous or endogenous data driving the model accounts for uncertainties (e.g. alternative ‘future worlds’). Complex science connected to practical policy ‘at the push of a button’ is alluring since it no longer requires stakeholders (especially hard pressed policy makers) to invest in understanding the science or its limitations. The danger is that all this complexity becomes a black box where only the inputs and outputs are visible.