This ranking is based on real-time data, which means that Delhi would have been at the top of that list on Nov. 10, when the AQI was at a record high.

Based on a 2019 average, 14 of the 20 cities with the world’s worst air were in India. The World Health Organization considers fine particulate matter pollution—known as PM2.5 pollution—to be safe at a level below 25 μg/m3 per day. In most parts of Delhi, the PM2.5 level has been roughly 10 times this threshold.

In view of these emergency conditions, Indian courts have also banned the use of firecrackers till Nov. 30, during which time the Hindu festival of Diwali also falls. Hindus consider lighting firecrackers as part of traditional Diwali celebrations.

Despite the ban, some Indians burnt firecrackers yesterday (Nov. 14), adding to the AQI woes. Keeping in mind this annual event—meteorological conditions that lead to an “air lock” in India’s north, and leads to PM2.5 and PM10 being trapped—Indians have often expressed the desire to migrate to other parts of India, or even the world.

For air-quality aspirants, these are currently the top 10 cities in the world with the best air.

📬 Sign up for the Daily Brief

Our free, fast, and fun briefing on the global economy, delivered every weekday morning.