Technical Note: Bayesian Model Averaging for Emergency Response Atmospheric Dispersion Multi-Model Ensembles: Is it Really Better? How Many Data Are Needed? Are the Weights Portable?

In the paper we investigate applicability of Bayesian Model Averaging (BMA) methodology to atmospheric dispersion multi-model ensemble system within the context of emergency response applications. BMA method can be used both to the evaluation of model predictions and for building combination of model results using BMA weighing factors. We analyze time evolution of BMA weights and we include a detailed quantitative comparison of different combinations of model results performed by the means of statistical indicators. The analysis allows us to identify similarities and differences among different combined models. Finally we raise the question of portability of BMA weights among various cases.JRC.F.8-Sustainable Transport (Ispra