Project Summary
University of Houston atmospheric science researchers have conducted a study to better understand the sources of ozone pollution in Houston. Their research revealed that while local emissions contribute to elevated ozone levels, the majority of excess ozone is transported from other regions, particularly from the central and northern United States. This complex phenomenon was studied during two ozone episodes in September 2021, a peak period for ozone due to weather patterns.
The researchers found that approximately 63% of excess ozone during these episodes came from transported pollution, while 37% was generated by local sources. The study also highlighted the crucial role of nitrogen oxides (NOx) and volatile organic compounds (VOCs) from industrial and vehicle emissions in ozone formation. Notably, long-lived oxygenated VOCs, such as acetone and formaldehyde, were found to significantly contribute to ozone production.
Using observational data from the TRACER-AQ field campaign and advanced computer models, the team simulated air movement and regional pollution chemistry to analyze the impact of both local and transported emissions. These findings underscore the importance of addressing both local emission control and regional pollution transport to develop effective strategies for mitigating ozone pollution and protecting public health in Houston.