Reactive trace gases comprise a fraction of the Earth’s atmosphere, yet their chemistry strongly influences many atmospheric processes, Earth’s climate, ecosystem functions, and our health. We are an atmospheric chemistry research group in the Department of Environmental Sciences at the University of Virginia focusing on (1) the spatiotemporal variability of pollutants within cities and their resulting disproportionate impacts, (2) mechanisms of atmosphere-biosphere exchange, focusing on specific organismal processes that alter atmospheric chemistry and composition, and (3) long-term trends in chemical oxidation, capitalizing on extemporary atmospheric experiments, conducting experiments that span multiple years, and using the wealth of multi-year composition data collected from the surface and space. We combine satellite, aircraft, ground-based field, and laboratory measurements to do this work.