The use of survey data to investigate ozone sensitivity to point sources

During the Southern Oxidants Study's 1992 Atlanta Intensive, a survey was conducted to improve the emission estimates from point sources for the Atlanta metropolitan region. The survey consisted of a questionnaire and a daily activity log for the largest point sources in the region. The point source information was used to compare a 1992 typical summer day's emissions with a specific day's emissions (10 August 1992). Both emission inventories indicate that about 90% of point source nitrogen oxides (NO x ) emissions were from power plants. Furthermore, our results show that the daily variation of point source NO x emissions during the Intensive Study was mostly due to the emissions from the power plants. The daily variation of NO x emissions with respect to a typical summer day was as much as 24%. Although the day-to-day variability in point source VOC emissions was as much as 28%, their contribution to the total VOC was not significant. Finally, we evaluate the impact of NO x emissions from power plants on ozone concentrations. Air quality model simulations show significantly different ozone concentrations depending on power plant location.