When
Monday, October 19, 2026, at 10:00 a.m.
Rachel Braun
Research Assistant Professor
School of Sustainable Engineering and the Built Environment
Arizona State University
"Impacts of Wildfire Smoke and Biogenic Emissions on Ozone Air Pollution in Metro Phoenix, Arizona"
Harshbarger 118A-A1
ABSTRACT
Metro Phoenix, Arizona has undergone rapid expansion and population growth in recent years. Alongside these changes, the region is currently in nonattainment of National Ambient Air Quality Standards set by the EPA for multiple criteria air pollutants, including ozone. Ground-level ozone forms through reactions of oxides of nitrogen and volatile organic compounds (VOC) in the presence of sunlight. The unique meteorological and ecological conditions in Metro Phoenix compared to many other urban areas across the United States present opportunities and challenges for studying factors leading to the formation of ground-level ozone in the region. This talk will explore two factors contributing to ozone pollution in Metro Phoenix: wildfires and biogenic VOC emissions from plants. Particular focus will be given to the many ways in which high temperatures impact the relationships between these sources and ozone formation, as the peak ozone season occurs during the summertime in Metro Phoenix.
ABOUT THE SPEAKER
Rachel Braun is a research assistant professor in the School of Sustainable Engineering and the Built Environment at Arizona State University. Rachel received her PhD in chemical engineering with a minor in atmospheric sciences from the University of Arizona in 2020. Her graduate work focused on aerosols and clouds in marine environments. She then worked as a postdoctoral researcher at Arizona State University with the Healthy Urban Environments Initiative that focused on issues related to heat and air pollution in Metro Phoenix. Her current work focuses on ozone pollution in Metro Phoenix.