An Assessment of the Emissions Inventory Processing Systems EMS-2001 and SMOKE in Grid-Based Air Quality Models

• Published in: Journal of the Air & Waste Management Association (1995) Vol. 53; no. 9; pp. 1121 - 1129
• Main Authors: Hogrefe, Christian, Sistla, Gopal, Zalewsky, Eric, Hao, Winston, Ku, Jia-Yeong
• Format: Journal Article
• Language: English
• Published: Pittsburgh, PA Taylor & Francis Group 01.09.2003; Air & Waste Management Association; Air and Waste Management Association; Taylor & Francis Ltd
• Subjects: Air Pollutants - analysis; Applied sciences; Atmospheric pollution; Emissions (Pollution); Environment; Environmental monitoring; Exact sciences and technology; Forecasting; Measurement; Models, Theoretical; Oxidants, Photochemical - analysis; Ozone - analysis; Photochemistry; Pollutants physicochemistry study: properties, effects, reactions, transport and distribution; Pollution; United States; USA, East; USA
• ISSN: 1096-2247; 2162-2906
• DOI: 10.1080/10473289.2003.10466261

In the United States, emission processing models such as Emissions Modeling System-2001 (EMS-2001), Emissions Preprocessor System-Version 2.5 (EPS2.5), and the Sparse Matrix Operator Kernel Emissions (SMOKE) model are currently being used to generate gridded, hourly, speciated emission inputs for urban and regional-scale photochemical models from aggregated pollutant inventories. In this study, two models, EMS-2001 and SMOKE, were applied with their default internal data sets to process a common inventory database for a high ozone (O 3 ) episode over the eastern United States using the Carbon Bond IV (CB4) chemical speciation mechanism. A comparison of the emissions processed by these systems shows differences in all three of the major processing steps performed by the two models (i.e., in temporal allocation, spatial allocation, and chemical speciation). Results from a simulation with a photochemical model using these two sets of emissions indicate differences on the order of ±20 ppb in the predicted 1-hr daily maximum O 3 concentrations. It is therefore critical to develop and implement more common and synchronized temporal, spatial, and speciation cross-reference systems such that the processes within each emissions model converge toward reasonably similar results. This would also help to increase confidence in the validity of photochemical grid model results by reducing one aspect of modeling uncertainty.