Impacts of dry deposition on atmospheric composition

We investigated the role of dry deposition, an often overlooked yet important loss pathway for numerous trace species, and its variations with meteorology and land use, in shaping observed distributions of ozone over the eastern United States. We used measurements from northern mid-latitude eastern U.S. forests and process-level models to advance the understanding of temporal variability in vegetative uptake of ozone, an air pollutant and greenhouse gas (Clifton et al., 2017 and 2019).  By coupling dry deposition in a chemistry-climate model with a dynamic vegetation model that includes land-use transitions, we examined variability in the dry depositional sink on time scales ranging from hours to decades, including during extreme climate and pollution events (Clifton et al., 2020a). We also found that interpreting observed ground-level ozone trends in terms of ozone precursor emission changes is likely sensitive to any large-scale changes in dry deposition (Baublitz et al., 2020). Our review on the processes controlling dry deposition over land is available here (Clifton et al., 2020b). [NSF Graduate Research Fellowship to Olivia Clifton; NOAA]