A study of the effects of vehicle emissions on the atmosphere of Sultan Qaboos University in Oman

Traffic jams have become a serious matter at Sultan Qaboos University (SQU) in Muscat, Oman due to an increase in student numbers. Therefore, the main objective of this research study is to apply the information gained by running CALPUFF software to model and investigate the concentration dispersion of the three most dominant vehicle emissions carbon monoxide (CO), mononitrogen oxides (NOx), and carbon dioxide (CO2) at SQU. The study was divided into two main parts: a line source study focused on investigating the dispersion of CO, NOx, and CO2 for a street located within the university's boundaries, and a study of the university domain as an area source. The study was based on statistical data collected on April 2, 2014, between 00h00 and 23h00 Local Standard Time (LST). Information related to both surface and upper air quality was obtained and processed into data files which were used to activate CALMET. For selecting vehicle emission factors, a comparison between different studies was conducted. CALPUFF line source case study simulation results showed that CO levels were within the allowable concentrations assigned by the United States' Environmental Protection Agency (EPA) standards. On the other hand, the NOx and CO2 simulated results were higher than the allowable amounts according to the EPA emission standards. Moving to the area source study, results demonstrated that the three pollutants significantly exceeded the allowable standards. The top five maximum concentrations were located near the origin of the study domain for both line and area source measurements. At the times that maximum concentrations were recorded, the wind was blowing from the sea toward the land. As a result, the greatest accumulation of pollutants was located close to the domain of the area of study.