A methodology for elemental and organic carbon emission inventory and results for Lombardy region, Italy

This paper presents a methodology and its application for the compilation of elemental carbon (EC) and organic carbon (OC) emission inventories. The methodology consists of the estimation of EC and OC emissions from available total suspended particulate matter (TSP) emission inventory data using EC and OC abundances in TSP derived from an extensive literature review, by taking into account the local technological context. In particular, the method is applied to the 2008 emissions of Lombardy region, Italy, considering 148 different activities and 30 types of fuels, typical of Western Europe. The abundances estimated in this study may provide a useful basis to assess the emissions also in other emission contexts with similar prevailing sources and technologies. The dominant sources of EC and OC in Lombardy are diesel vehicles for EC and the residential wood combustion (RWC) for OC which together account for about 83% of the total emissions of both pollutants. The EC and OC emissions from industrial processes and other fuel (e.g., gasoline, kerosene and LPG) combustion are significantly lower, while non-combustion sources give an almost negligible contribution. Total EC + OC contribution to regional greenhouse gas emissions is positive for every sector assuming whichever GWP100 value within the range proposed in literature. An uncertainty assessment is performed through a Monte Carlo simulation for RWC, showing a large uncertainty range (280% of the mean value for EC and 70% for OC), whereas for road transport a qualitative analysis identified a narrower range of uncertainty.