An Analysis of the Relationship Between Tropospheric Ozone Pollution and Synoptic Conditions in Phoenix, Arizona

High levels of surface ozone pollution have been shown to have adverse effects on human health and our environment. For at least the past decade, ozone concentrations in Phoenix, Arizona have been above the federal health standard, set in place by the Environmental Protection Agency. It is crucial that all factors contributing to rising tropospheric ozone levels within the Phoenix metropolitan area are analyzed to better understand this risk for future mitigation efforts. Consequently, the primary objective of this study is specifically to examine meteorological factors' influence on Phoenix’s ground level ozone by comparing days of ozone exceedances with ozone non-exceedances days over the course of 2010-2020. To carry out this research, various weather conditions for both exceedance and non-exceedance ozone days were studied using unpaired Student’s t-tests and Pearson product-moment correlation tests. The results of this study suggest that the most significant factors that are associated with the occurrence of surface ozone exceedances in Phoenix are wind speed and temperature, whereas the least significant variables are wind direction and sky conditions. This indicates that more stable synoptic conditions in which skies are clearer, allowing for higher temperatures and more stagnant air movement, are ideal for ozone production leading to an ozone exceedance. The results from this honors thesis will be useful as it will aid in greater understanding of the relationship between Phoenix’s surface ozone and weather, aiding future ozone forecasting.