The importance of the residual layer in characterizing ozone episodes in East Tennessee

This thesis was written to characterize episodes of high concentrations in East Tennessee. The trajectory ozone analysis of high pressure air masses revealed that the trajectory of a high pressure system impacting East Tennessee was not as important as whether the system stagnated. Four ozone episodes have also been analyzed. In May 1992, stations representative of the residual layer observed an excellent example of a nocturnal increase of ozone due to regional transport that contrasted a simultaneous decrease in ozone concentrations at nearby low altitude monitors. Using ozone isopleth maps and comparisons of individual stations representative of the residual layer and the mixed layer in the three other episodes, it was found that the residual layer can store and transport ozone concentrations of 80-120 parts per billion or greater over large areas. Furthermore, convective mixing the following day can make these concentrations the most important source of ozone for rural areas and small cities similar to Knoxville, where the daily maximums may be within 5-20 parts per billion of the background concentration in the residual layer as measured at White Top Mountain and Mount Mitchell. Thus, this research demonstrates the need for additional studies of vertical concentrations of ozone to determine a community's typical background ozone concentrations and true production rates. photo-chemical