Fig. 3From: Air quality index variation before and after the onset of COVID-19 pandemic: a comprehensive study on 87 capital, industrial and polluted cities of the worldHeat Map created with GraphPad Prism showing average medians of the four first months the AQIs following 2020 lockdown and comparisons with 2018, 2019 and 2021. A AQI-PM2.5 variation, B AQI-PM10 variation, C AQI-SO2 variation, D AQI-NO2 variation, E AQI-CO variation and F AQI-O3 variationBack to article page