Modeling Ozone in the Eastern United States Using a Fuel-Based Mobile Source Emissions Inventory
Monday, 14 December 2015: 09:15
3010 (Moscone West)
A fuel-based mobile source emissions inventory of nitrogen oxides (NOx) and carbon monoxide (CO) is developed for the continental US. Emissions are mapped for the year 2013, including emissions from on-road gasoline and diesel vehicles, and off-road engines. We find that mobile source emissions of NOx in the National Emissions Inventory 2011 (NEI11) are 50-60% higher than results from this study; mobile sources contribute around half of total US anthropogenic NOx emissions. We model chemistry and transport of emissions from the NEI11 and our fuel-based inventory during the Southeast Nexus (SENEX) Study period in the summer of 2013, using the Weather Research and Forecasting with Chemistry (WRF-Chem) model. In the Eastern US, there is a consistent over-prediction of tropospheric ozone (O3) levels when simulating emissions from the NEI11, with the largest biases located in the Southeastern US. Using our fuel-based inventory, we test O3 sensitivity to lower NOx emissions. We highlight results in the Southeast, a region with significant interactions between anthropogenic and biogenic emissions of ozone precursors. Model results of NOy, CO, and O3 are compared with aircraft measurements made during SENEX.