As winter sets in, a dense layer of toxic smog has descended over Delhi, driving the city’s air quality down to its worst level in eight years. Air pollution levels have deteriorated rapidly since the end of October, remaining hazardous every day since November 12. On November 18, the Air Quality Index (AQI) hit 494, plunging the city’s pollution levels into the “severe plus” category, the worst classification possible. Anything up to 50 is deemed “good”; beyond 200 is “poor.”
This smog, composed mainly of fine particulate matter, known as PM2.5, has engulfed what was already the → Continue reading at Wired - Science