|Title||Improving CEA: moving from expert judgement to more quantitative approaches|
|Author(s)||Piet, G.J.; Jongbloed, R.H.; Tamis, J.E.; Vries, P. de|
|Event||ICES Annual Science Conference 2018, Hamburg, 2018-09-24/2018-09-27|
|Publication type||Abstract in scientific journal or proceedings|
|Abstract||Currently the most comprehensive cumulative effects assessment (CEA)
framework in terms of human activities and their pressures affecting the ecosystem components of the North Sea is still based on semi-quantitative scores from expert judgement. The outcome of this CEA is strongly determined by the estimation of the severity of the interaction which suffers from the fact that it only has three impact categories, i.e. none, chronic and acute, which capture the effect at the level of the individual but without any consideration of how this translates to population -level effect which best represents the actual
impact risk. Also, while Exposure appears adequately covered with both a spatial and a temporal component (albeit still based on expert judgement), the intensity of the pressure which together with the sensitivity of the population determines the severity and hence the population-level impact risk is ignored. In this study we show how a CEA can be improved by including quantitative information that adequately covers the above issues. We also present a framework that determines the confidence level of the CEA depending on the (quality of the) information used and methodological choices. This framework can be used to guide the development of science to improve the confidence level.