Delhi is facing a serious environmental crisis as dense fog and extreme air pollution grip the city. The Air Quality Index (AQI) has climbed close to 400, which falls under the “severe” category. While residents woke up to thick fog across Delhi and the NCR, the bigger danger is the highly polluted air people are breathing every day.
According to the India Meteorological Department (IMD), visibility at the Indira Gandhi International Airport was very poor. At 10:00 UTC, visibility dropped to just 1.1 kilometres, and the runway visual range was around 2 kilometres. Because of this, flight services were badly affected. Around 78 incoming flights and 70 outgoing flights were cancelled, and two flights had to be diverted. The previous day saw even worse disruption, with 118 flights cancelled. Although CAT-III landing systems are in use, delays continue.
Experts explain that fog makes the pollution problem worse. When fog forms, it traps harmful pollutants close to the ground instead of allowing them to disperse. This leads to a sharp rise in pollution levels and increases health risks, especially for children, the elderly, and people with breathing problems. If the fog continues, AQI levels are expected to rise further. This is not a new issue for Delhi. Over the past ten years, the city’s average AQI during December has mostly stayed in the “very poor” to “severe” range, showing how serious and long-lasting the pollution problem is. In December 2025, the average PM2.5 level was recorded at 212 micrograms per cubic metre, while PM10 levels were even higher at 341 micrograms per cubic metre. These numbers confirm that harmful particulate matter remains the main pollutant affecting Delhi’s air quality.
