Observations of Air Pollution During High Ozone Days in San Antonio and Austin, Texas

The two largest metropolitan areas in Central Texas, San Antonio and Austin, have been experiencing rapid growth and face challenges meeting the National Ambient Air Quality Standards (NAAQS). San Antonio is in nonattainment with the NAAQS ozone standard. Austin’s ozone design value reached above the ozone standard in 2023 and its PM_2.5 design value is above the recently lowered NAAQS PM_2.5 standard of 9.0 μg/m³. In this work, we characterize some of the factors that contribute to high ozone days and PM_2.5 episodes in 2024 in the San Antonio and Austin metropolitan areas. Our analysis combines NASA's high-resolution Tropospheric Emissions: Monitoring of Pollution (TEMPO) satellite, new Pandora and AERONET ground-based remote sensing data, and existing in situ observations from monitoring stations. The use of the novel high-resolution air pollution observations can improve our understanding of pollutant dynamics, which in turn can inform mitigation strategies and public health policies.