Haze blankets China

Left: A thick layer of haze blanketed the North China Plain on October 9, 2014. On that day, PM2.5 levels were 13 times higher than the level the WHO considers safe for 24-hour exposure. The graphic on the right shows PM2.5 exposure intensity, calculated using days of heavy pollution and population density. Graphics via NASA and Beijing City Lab.

Sources: https://plus.google.com/+NASAEarthObservatory/posts/YTeFK84Qwpo and https://www.beijingcitylab.com/working-papers/