Heatmaps showing adjusted mean variations in terms of PM2.5 between the 2019 and 2020 study periods by sensor and daily hour intervals.

Each heatmap row represents graphically the adjusted mean variation in terms of PM2.5 and PM10 between 2019 and 2020 over the complete set of Purple Air sensors (All sensors) and by sensor (PA-S1 –PA-S23) over daily hours intervals defined. Shades of green are proportional to the estimated magnitude of the reduction in terms of PM2.5 between 2019 and 2020; shades of red are proportional to the estimated magnitude of the increase in terms of PM2.5 between 2019 and 2020 as showed by the colors legend on the right side of each plot. The “+” symbol denotes an increase in terms of pollutants concentration between year 2019 and 2020.

Read more here: Source link