Fig. 5: Global daily risk exposure to ambient PM2.5 pollution.
From: First close insight into global daily gapless 1 km PM2.5 pollution, variability, and health impact
Spatial distributions of global daily exposure risks with the percentages (unit: %) of days exceeding the WHO-recommended four short-term interim targets: a S-IT1 (daily PM2.5 > 75 μg m−3), b S-IT2 (daily PM2.5 > 50 μg m−3), c S-IT3 (daily PM2.5 > 37.5 μg m−3), d S-IT4 (daily PM2.5 > 25 μg m−3), and e short-term air quality guideline (S-AQG) level (daily PM2.5 > 15 μg m−3) at each 1-km2 grid in areas with a population density > 1 per km2 for the year 2022. Square insets zoom in on hot spots with high daily PM2.5 exposure risks in mega-cities (A-J). The (i–v) bar charts show the percentages (unit: %) of populated areas that have at least 1, 7, or 30 days exceeding the WHO daily air quality standards for the global, developed, and developing world. The line chart plots in (vi) show the percentages (unit: %) of populated areas as a function of WHO daily air quality standards for developed and developing countries (i.e., solid and dashed lines, respectively) and for exposure periods of 1 day, 7 days, and 30 days (different colored lines). The maps were created using ESRI ArcGIS Pro 3.0.1.
