Traffic flow and road network-based spatial allocation of regional mobile source emission inventories

In order to address the bias brought by traditional methods for spatial allocation of mobile source emission inventories into grid cells, a new approach named "standard road length" is proposed in this study. The new approach makes use of the GIS-based road network information and traffic flows to help allocate the mobile source emission inventory into the grid cells. The approach was demonstrated by the spatial allocation of the regional mobile source emission inventories in the Pearl River Delta (PRD). The results show that spatial distributions of emissions from mobile sources using the new approach are consistent with distributions of regional road network systems. The consistency implies that the new approach is promising in reducing spatial bias in spatial allocation of emissions, especially as the grid cell size decreases.