Viability, efficiency, resilience and equity: Using very diverse indicators to deal with uncertainties of future events

Abstract

Dynamic models can help adapt to climate change since they inform on the impacts of decisions and future events on sustainability. They make it possible to follow the evolution of variables over time, to model exogenous events and adaptive policies and to compute sustainability indicators. Various model types based on different worldviews exist, and they give rise to different indicators. Modellers generally choose only one type of model, limiting the variety of indicators. However, decision-makers, who have to be creative to face global change, need a wider diversity of indicators. The objective of this paper is to show the diversity of insights one can get by using alternative system indicators and their decision implications. We test our “very diverse indicators” approach and illustrate its results for a population at risk of flooding and a water-basin manager who can help the population implement protection measures. We test many variations, including e.g. viability theory and agent-based modelling, and different indicators of viability, resilience, efficiency and equity, based on comparable data sets. We show possible synergies of the obtained diversity of insights: for example, one indicator says that it is urgent to act and another which is the best policy to use. We discuss the difficulties of implementation and the benefits of our approach for the decision-maker.