This experiment aims to perform a multi-model evaluation against reanalysis meteorological fields combined with ground-based observations of aerosol properties in a trajectory-based Lagrangian framework. The representation of source and transport dependence of aerosols to different regions will be examined. Applying trajectory calculations to the meteorological fields from reanalysis and GCM data for the same location and time-period facilitates a highly transparent means for evaluating the discrepancies between models and observations as a function of aerosol source/sink pathways during transport to a measurement station. This analysis technique will have wide scientific relevance as it facilitates tracing the aerosol evolution during transport to investigate the role of sources, dynamical processes and sinks on the aerosol properties in the model. For further details, see experiment documentation linked below.