Fig. 2: Diurnal PM2.5 profile in Kigali.
From: Detecting urban PM2.5 hotspots with mobile sensing and Gaussian process regression

a Overall average and b averages by day of the week. The daily pattern of PM2.5 concentrations was observed to be fairly similar across all days of the week. Times are given in the local timezone (Central African Time, UTC+02:00).