Contribution of different vehicle types to primary and secondary PM2.5 in Europe

Over recent years, research has largely concentrated on emissions from passenger cars, while other on-road vehicle categories -such as two-wheelers, buses, and heavy-duty trucks- have received less attention. Consequently, their influence on regional air quality and PM_2.5 concentrations remains uncertain. To address this gap, the three-dimensional chemical transport model PMCAMx was applied together with the EASVOLEE (Effects on Air Quality of Semi-Volatile Engine Emissions) emission inventory to quantify the impact of a broad range of on-road vehicle types, including passenger cars, two-wheelers, trucks, and buses, on atmospheric particulate matter.

PMCAMx was applied all over Europe, with a particular focus on selected areas of interest using multiple nested grids with progressively increasing spatial resolution. Organic aerosol (OA) processes were represented using the one-dimensional Volatility Basis Set (VBS) framework, which treats both primary and secondary OA as chemically reactive and semi-volatile components.

The simulations assess the contributions of the different vehicle types to primary and secondary, organic and inorganic PM_2.5 levels. The contributions of volatile (VOCs), intermediate volatility (IVOCs), semi-volatile (SVOCs) and low volatility (LVOCs) organic compounds are also quantified. Seasonal variability was also investigated.