Delhi Air Quality Swings Between 'Severe' and 'Very Poor'; AQI at 318

New Delhi: The air quality index in Delhi continued to swing between the "severe" and "very poor" levels. The city's 24-hour average air quality index, recorded until 4 pm on Sunday, was 318 (very poor), improving from the severe category recorded the previous day when it was 412, according to data from the Central Pollution Control Board (CPCB).

Decrease in Severe AQI Stations, But Pollution Levels Remain High

None of the 38 monitoring stations in Delhi recorded AQI in the severe category on Sunday, compared to 20 stations that recorded severe air quality the previous day, according to the SAMEER app, which provides hourly updates on the National Air Quality Index.

PM2.5 Levels Remain Hazardous for Health

An AQI between 0 and 50 is considered "good," 51-100 "satisfactory," 101-200 "moderate," 201-300 "poor," 301-400 "very poor," 401-450 "severe," and above 450 "severe plus." CPCB data identified PM2.5 as the primary pollutant, with its levels recorded at 138 at 3 pm.

PM2.5 particles, measuring 2.5 micrometers or smaller (about the width of a human hair), pose serious health risks as they can enter the lungs and bloodstream, according to the CPCB.

Sources of Pollution: Vehicular Emissions and Stubble Burning

The Centre's Decision Support System (DSS) for Air Quality Management estimated that vehicular emissions contributed 18.1 per cent to Delhi's pollution on Sunday. Stubble burning, another major factor, accounted for 19 per cent of Delhi's pollution on Saturday.

The DSS provides daily estimates for vehicular emissions, while data on stubble burning is typically released the following day.

Pollution Crisis Reaches Dangerous Levels

Delhi's air quality dropped to the hazardous category last Sunday morning, with the AQI crossing 450 for the first time this season.

It got worse on Monday, reaching the season's highest average Air Quality Index (AQI) of 495. In response, Stage 4 restrictions under the Supreme Court-mandated Graded Response Action Plan (GRAP) were implemented across the city to address the worsening air pollution crisis.

Slight Improvement, But Hazardous Conditions Persist

According to data, the city's air quality stayed in the severe category from Monday to Wednesday. While there was a slight improvement on Thursday and Friday, it returned to the severe category on Saturday.

Thick Smog and Unusual Temperatures in the City

Meanwhile, a thick layer of mist and smog covered the city in the morning and evening, reducing visibility.

The daytime temperature was recorded at 29.1 degrees Celsius, two degrees higher than usual for this time of year, according to the India Meteorological Department (IMD).

Weather Forecast: Moderate Fog Expected on Monday

Humidity levels fluctuated between 96 and 76 per cent during the day.

The IMD has forecast moderate fog for Monday, with maximum and minimum temperatures expected to be around 28 and 12 degrees Celsius, respectively.