Evaluation of AERMOD for Near-Road Pollutant Dispersion Using Data from the General Motors Sulfur Dispersion Experiment
There is an increasing need to investigate the adverse health effects associated with exposure of transportation-related air pollutants. Hence, it is important to evaluate the accuary of dispersion models in predicting near-roadway pollutant concentrations. In the present study, the capability of the steady-state plume dispersion model AERMOD to model near-roadway pollutant dispersion was assessed and validated using the General Motors (GM) Sulfur Dispersion Experiment. It was found that in general, the AERMOD is capable of predicting a conservative tracer (SF6) concentrations at both surface (0.5 m) and higher elevations (3.5 and 9.5 m) at downwind locations. The model performance decreases as elevation increases, with a much smaller overall fractional bias (FB) of -0.237 at surface level and higher FB values of -0.479 and 0.796 at 3.5 and 9.5 m, respectively. This indicates a necessity in improving the vertical distribution of pollutants in AERMOD. The model performance under low wind conditions can be greatly improved by enforcing a minimal horizontal dispersion parameter (sigma-v) of 0.3 m s⁻¹ and wind speed of 1 m s⁻¹. However, AERMOD is not capable of predicting concentrations at upwind locations for both high and low wind speed cases. In addition, the predicted vertical concentration fields show abnormal bands of high concentrations at higher elevations when the wind direction is parallel (regardless of wind speed) or oblique (less than 1 m s⁻¹) to the road. Enforcing a minimal wind speed and sigma-v leads to slightly improved concentration fields but the abnormal bands cannot be completely eliminated.
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Supplemental Notes:
- This paper was sponsored by TRB committee ADC20 Standing Committee on Transportation and Air Quality. Alternate title: Evaluation of AERMOD for Near-Road Pollutant Dispersion Using Data from General Motors Sulfur Dispersion Experiment
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Corporate Authors:
500 Fifth Street, NW
Washington, DC United States 20001 -
Authors:
- Askariyeh, Mohammad Hashem
- Kota, Sri Harsha
- Vallamsundar, Suriyapriya
- Zietsman, Josias
- Ying, Qi
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Conference:
- Transportation Research Board 96th Annual Meeting
- Location: Washington DC, United States
- Date: 2017-1-8 to 2017-1-12
- Date: 2017
Language
- English
Media Info
- Media Type: Digital/other
- Features: Figures; References; Tables;
- Pagination: 13p
- Monograph Title: TRB 96th Annual Meeting Compendium of Papers
Subject/Index Terms
- TRT Terms: Dispersions (Chemistry); Pollutants; Roadside; Sulfur
- Identifier Terms: AERMOD (Computer model)
- Subject Areas: Environment; Highways;
Filing Info
- Accession Number: 01628698
- Record Type: Publication
- Report/Paper Numbers: 17-05268
- Files: TRIS, TRB, ATRI
- Created Date: Mar 8 2017 5:09PM