Fig. 2: Spatial and temporal variation in fine particulate matter (PM2.5) and its species.
From: Local incomplete combustion emissions define the PM2.5 oxidative potential in Northern India

Standardized monthly variation of PM2.5 and its species except OA for five sites (a, c, e, g, i, k, m). The temporal anomaly (y-axis) for each sampling site was calculated from 9-12 (Jan), 8-9 (Feb), 5-6 (Mar), 5 (Apr), and 5 (May) daily samples as: ((absolute value – temporal site average (μ))/temporal site standard deviation (σ)). The colored solid lines and corresponding shaded area represent site-specific temporal anomaly and its ±1σ. A thick black dashed line represents the overall averaged spatial variation. The absolute values of the same parameters are shown as box whisker plots [line/box: median and 25th-75th percentile; upper and lower end of whisker: 10th-90th percentile] in the (b, d, f, h, j, l, n).