Use of overseas emissions models to predict traffic emissions in urban areas: technical note.

This note explores potential discrepancies between Australian test data, a newly developed Australian emission algorithm and predictions from two commonly used international traffic emission models. These emission models require input that can readily be extracted from macroscopic traffic models. We have found substantial discrepancies, i.e. mean NOx prediction errors for a stretch of freeway are a factor of 1.6 to 2.0 higher for overseas models, when compared to an Australian average speed model that was developed using Australian test data. (a).