 "In Graphics l What AQI does and does not tell you")
New Delhi and its surrounding towns are currently blanketed in a dense haze, with air quality deteriorating by the day.
According to live data from the Swiss organisation IQAir, Delhi now holds the unenviable title of the worst global capital, with the Air Quality Index (AQI) breaching the 400 mark.
For Delhi residents, this situation is all too familiar. Each winter, they contend with smog—a hazardous blend of smoke and fog—as cold air traps dust, vehicle emissions, and smoke from illegal stubble burning.
Also read: Winter is here: How Delhi is choking on thick smog and poor air
The thick smog has severely impacted visibility, leading to disruptions in flights and train services across the capital and its vicinity. On Friday, the Delhi government responded by implementing anti-pollution measures under GRAP Stage III to address the alarming AQI levels.
But what does AQI actually represent, and how is it calculated? Let’s explore this in more detail.
 "Russian drones over Poland: Trump’s tepid reaction a wake-up call for Nato?")
 "As Russia pushes east, Ukraine faces mounting pressure to defend its heartland")
 "Why Mossad was not on board with Israel’s strike on Hamas in Qatar")
 "Turkey: Erdogan's police arrest opposition mayor Hasan Mutlu, dozens officials in corruption probe")
 "Russian drones over Poland: Trump’s tepid reaction a wake-up call for Nato?")
 "As Russia pushes east, Ukraine faces mounting pressure to defend its heartland")
 "Why Mossad was not on board with Israel’s strike on Hamas in Qatar")
 "Turkey: Erdogan's police arrest opposition mayor Hasan Mutlu, dozens officials in corruption probe")
