Figure 2.

Map of Atlanta mobile monitoring data for three pollutant metrics. Data spatially binned into a grid with 300 m × 300 m cell size, and the median was calculated for each bin. Color scale represents quantiles of the resultant spatial bins. Original PN₂₅ concentrations have been adjusted by aligning data collected on separate days using the daily 5^th percentile. PN₂₅ concentrations presented are the incremental concentration change from the 5^th percentile; there are no negative measurements in the original data. Particle size and PN₂₅/PN₅₀ are calculated with the original (unaligned) data Figures a, c, and e: The solid blue box encloses the airport transects and the dashed blue lines leading to ATL airport indicate approximate approach paths to the two landing strips (see supplemental Figure S3). Figures b, d, and f: The black box indicates the zoomed-in spatial region displayed in Figures a, c, and e.