Publication Date


Degree Program

Department of Geography and Geology

Degree Type

Master of Geoscience


Throughout the United States, many areas exceed the level of safe ground ozone (O3) concentration. Non-natural emissions made as result of daily human activities and natural emissions react photochemically to produce ground O3 concentration. Variation in ground O3 concentration is controlled by local and regional emissions, synoptic and mesoscale meteorology, and boundary layer chemistry and dynamics. When the right meteorological variables are present, rural areas can have unhealthy air conditions with high levels of ground O3 concentration similar to that of metropolitan areas. Particular ground O3 concentration episodes were analyzed to summarize what meteorological variables constitute a healthy or hazardous ground O3 day. Hourly ground O3 data for Mammoth Cave National Park from the years, 1998 through 2003 were analyzed. Once analyzed, a combination of meteorological variables is used in a simple linear regression to create the coefficients for empirical predictive model based on 1998-2000 data. The meteorological variables included maximum temperature (Tmax), diurnal temperature range (DTR), solar radiation (SR), and daily precipitation (Pd). The meteorological coefficients were then used with the available meteorological data from 2001 through 2003 to predict ground O3 for 2001 through 2003. Certain meteorological variables such as SR are not easily available in most regions and rural sites in the United States. Therefore, SR was excluded from the regression model to see if rural areas can also forecast ground O3 sufficiently. Root mean square error, d-index, and mean absolute error were used to assess the performance of the predictive model. These measures were calculated to find out if a significant relationship between ground O3 and the meteorological variables is present. For example, the d-index was calculated and ranged from 0.81-0.84 for the best regression model performances. This suggests that the predictive ground O3 from 2001 through 2003 is in agreement with observed ground O3 from 2001 through 2003.


Earth Sciences