Delhi-NCR Faces Double Blow of Smog and Fog; AQI Crosses 500 in Parts of Region
Delhi and neighbouring NCR areas continued to struggle with poor air quality on November 10, the day after Diwali, as a thick layer of smog and morning fog affected several locations. Firecracker emissions added to the pollution, while low visibility caused inconvenience for commuters during the early hours.
Visuals recorded around 6:45 am showed a thick haze over several parts of the capital, including Akshardham and Sarai Kale Khan. Streetlights appeared less effective through the polluted air. Visibility was also reduced on several roads, slowing down traffic.
CPCB Records Poor to Very Poor Air Quality
According to Central Pollution Control Board (CPCB) figures cited in the report, the AQI near India Gate and Kartavya Path stood at 258, falling in the 'poor' category. The reading around Safdarjung was 371, classified as 'very poor'. Dhaula Kuan recorded an AQI of 194, categorised as 'moderate'.
Ambala in Haryana recorded an AQI of 250, placing it in the 'poor' category.
Private AQI Readings Show Extremely High Levels in NCR
Separate readings from AQI.in, collected from different locations at around 8 am, showed extremely high pollution levels in parts of Delhi-NCR.
New Delhi: 480
Defence Colony: 476
Greater Kailash: 450
Noida: 370
Ghaziabad: 381
Gurugram: 526
Faridabad, Sector 11: 501
These are private platform readings and should be distinguished from CPCB monitoring-station figures.
Visibility Improves at Delhi Airports
The India Meteorological Department reported an improvement in visibility at Safdarjung and Palam airports compared with November 9. At Safdarjung, visibility improved from 100 metres on November 9 to 1,000 metres on November 10. The lowest visibility during the latest fog episode was 500 metres at 6:30 am. Visibility remained below 1,000 metres from 4:30 am to 8 am. At Palam, visibility increased from 600 metres to 800 metres, with shallow fog reported. It was still below 1,000 metres at 8 am.
Why Do AQI Readings Differ?
Explaining the difference between monitoring systems, IIT Delhi Professor Mukesh Khare of the Civil Engineering Department said CPCB stations use scientific methods to measure pollutants such as PM2.5, PM10, nitrogen dioxide and sulphur dioxide. Private agencies often use sensor-based systems. Their readings can be affected by sensor quality, calibration, temperature, humidity and local weather conditions. Therefore, readings from private platforms may differ from those recorded by standardised CPCB monitoring stations.
