Investigating The Impact of initial and Boundary Concentrations on Air Quality Modeling Accuracy Over Tehran

Document Type : Original Articles


1 MSc. Student of Mechanical Engineering, Department of Mechanical Engineering, Sharif University of Technology, Tehran

2 Assistant Professor, Department of Mechanical Engineering, Faculty of Energy Conversion, Sharif University of Technology, Tehran

3 Assistant Professor, Department of, University of Shahid Beheshti, Tehran


In this study, the performance of WRF/CAMx modeling system in predicting primary and secondary gasephase pollutants is evaluated. The main goal of this research was investigating the impact of initial and boundary concentrations, used to feed the CAMx model, on the accuracy of the model and the level of pollutants over Tehran modeling domain. For this purpose, CAMx model was ran in two cases with different initial and boundary concentration. The model performance in two cases compared against observations measured at air quality monitoring stations. Results showed significant impact of initial and boundary concentrations on model accuracy and level of pollutant concentrations over the city. When using constant zero initial and boundary concentrations model showed poor performance in predicting level of pollutants and daily maximum concentrations, especially for NO2and O3concentrations which mostly produce during chemical reactions in the atmosphere. But using MOZART data to prepare initial and boundary concentrations lead to improve in model accuracy and predicting daily maximum concentrations.


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