Delhi's Air Quality Reaches Hazardous Levels as Weak Winds Trap Pollutants Across NCR Region

New Delhi:

Delhi's air quality deteriorated significantly on Sunday due to weak wind conditions that trapped pollutants, pushing the overall Air Quality Index (AQI) to 366, placing it firmly in the "very poor" category. Three monitoring stations recorded "severe" air quality with readings above 400, according to data from the Centre Pollution Control Board.

The concentration of PM2.5 particles reached 189.6 micrograms per cubic metre, while PM10 levels stood at 316. PM2.5 consists of fine inhalable particles with diameters of 2.5 micrometres or smaller, whereas PM10 encompasses slightly larger particles up to 10 micrometres in diameter, as defined by the CPCB.

These elevated pollution levels can cause respiratory discomfort, particularly affecting vulnerable populations such as those with pre-existing lung or heart conditions, children, and elderly individuals.

The overall AQI jumped dramatically from 303 the previous day to 366, reflecting a substantial deterioration in air quality conditions.

In neighboring regions, Haryana's Dharuhera recorded an AQI of 434, categorized as "severe," while Maharashtra's Bhiwandi registered "very poor" air quality with an AQI of 376—both readings worse than Delhi's.

Other cities in the National Capital Region (NCR) also experienced "very poor" air quality: Ghaziabad (351), Gurugram (357), Noida (348), and Greater Noida (340). Faridabad fared somewhat better with a "poor" AQI reading of 215.

According to the Air Quality Early Warning System (AQEWS) for Delhi, wind speeds dropped below 8 kmph from the northwest direction during evening and nighttime hours, significantly hindering the dispersion of pollutants.

The AQEWS noted that a ventilation index below 6,000 m²/s combined with wind speeds under 10 kmph creates unfavorable conditions for pollutant dispersal.

The forecast indicates that air quality is likely to remain in the "very poor" category until November 4.

Within the capital, three monitoring stations recorded "severe" air quality with AQI readings exceeding 400, with Wazirpur reporting the highest level at 413.

An additional 28 stations registered "very poor" air quality with readings above 300, according to the CPCB's Sameer application.

For reference, the CPCB classifies AQI values as follows: 0-50 is "good," 51-100 "satisfactory," 101-200 "moderate," 201-300 "poor," 301-400 "very poor," and 401-500 "severe."

Temperature readings in Delhi on Sunday showed a maximum of 30.7 degrees Celsius, 0.5 degrees below the seasonal average, while the minimum temperature was 16.8 degrees Celsius, 1.5 degrees above normal, according to the India Meteorological Department (IMD).

Humidity levels stood at 75 percent at 5:30 PM.

The weather office has forecast shallow fog for Monday, with expected maximum and minimum temperatures of around 30 and 15 degrees Celsius, respectively.

As part of pollution control measures, a ban on the entry of commercial vehicles not registered in Delhi and those not compliant with BS-III or lower emission standards came into effect in the national capital on November 1.