What the AQI Number on Your Phone Actually Measures
An AQI of 180 sounds alarming, but what is it counting? Here’s how India’s Air Quality Index is worked out, what its colours mean, and why different apps show different numbers for the same air.
Air and weather
Smog in winter, the monsoon’s arrival, the AQI number on your phone: the air and weather shape daily life in India more than most of us realise.
This topic explains what the numbers mean, where they come from and what you can do with them.
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- Why the Monsoon Reaches Kerala First
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