Integrated Scenario Modelling for Managing Catchments

Abstract: Integrated Scenario Modelling (ISM) is discussed as a tool to perform integrated assessment in catchments for improved sustainability outcomes. ISM applies scenarios as model inputs which take into account achievable policy/management drivers and socioeconomic capacity for change, as well as uncontrollable system shocks. It computes, as model outputs, indicators covering a spectrum of biophysical and socioeconomic impacts for each scenario. Given the complex nature of catchment problems, the broad objectives of ISM should be to understand the directions and magnitudes of change in relation to management interventions, so as to compare associated outcomes. Central to this objective is the need for improved techniques of uncertainty and sensitivity analysis, to provide a measure of confidence in the ability to choose between different management decisions. Three examples of problems treated with an ISM approach are discussed. The way in which their differing contexts influence the integration into scenario modelling illustrates the choices made in model construction