The role of numerical models in environmental decision-making

Modelling is undertaken for a variety of reasons. The pre-sent short discussion focuses on everyday model usage as undertaken by government and consulting companies to assist in environmental management. In this context, a model’s purpose is to predict the behaviour of a system under a management regime which is not yet in place or has just started. The term management regime may refer to excavation of a mine, extraction of water, contaminant remediation, allocation of water for irrigation, etc. A common aspect of all these prac-tices is evaluation of the risk of bad things happening. The decision-making process should include exploration of the costs and benefits associated with alternative management practices, and quantification of risks accompanying different management decisions...