Impact of smoke on ozone, aerosols and oxidant chemistry in urban and rural areas in the U.S.

Wildfire smoke regularly impacts millions of people around the U.S. As part of the NOAA/NASA Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) and NSF Western Wildfire Experiment For Cloud Chemistry, Aerosol Absorption And Nitrogen (WE-CAN) measurement campaigns, the community has collected an unprecedented amount of data and knowledge on fire emissions and in-situ smoke plume chemistry. However, much less is known about how these plumes mix and interact with anthropogenic emissions in urban areas and in the wildland-urban interface (WUI). This project will examine several key questions regarding O3 formation, oxidant production, aerosol sources and smoke identification. Specific objectives include: (1) Use a detailed chemical box model to examine multiple smoke scenarios in urban and rural areas to better understand O3 and oxidant production; (2) Examine observations in urban and rural locations to evaluate the consistency of PM2.5/CO/NOx/O3 enhancement ratios measured from individual plumes by aircraft observations; (3) Use long-term data from satellite indicators combined with surface observations of PM2.5 and smoke tracers to improve identification of smoke at the surface, especially for low smoke concentrations, and therefore improve our understanding of smoke impacts.