Pollution levels become severe in Delhi and visibility decreases

Pollution levels in Delhi reached extremely hazardous levels on Friday morning, with the city's average air quality index (AQI) recorded at 494 at 7.31 am, according to an ANI report. As per data from the Central Pollution Control Board (CPCB), the AQI was 403 even at 8.40 am. Due to thick smog and pollution, visibility decreased in several areas of the city, and pollution levels were recorded as severe at many monitoring stations.

According to CPCB data, an AQI between 401 and 500 falls in the severe category. This type of severe pollution can affect even healthy people, while it can create more serious difficulties for those who already have health problems. Vehicle emissions, industrial activities, construction dust, waste, and biomass burning are the main causes of pollution. Low wind speed, limited atmospheric mixing, and temperature inversion can trap pollutants near the ground and slow down their dispersion process. Fog contains tiny water droplets, while smog contains air pollutants such as particulate matter and gases. Both together can reduce visibility and degrade air quality.

According to CPCB figures, IIT Delhi was one of the most affected locations where an AQI of 488 was recorded. This was followed by 455 in ITO, 451 in JNU, 419 in Anand Vihar, 413 in Rohini, and 402 AQI was recorded at Rajokri Border. All these areas were in the severe category. Air quality was also very poor in other parts of the capital, and an AQI of more than 400, i.e., in the severe category, was recorded at more than 33 stations.

The Delhi government has deployed water sprinklers across the city to fight pollution. Under Stage III of the Graded Response Action Plan (GRAP), measures including bans on unnecessary construction and demolition have been taken.

On the other hand, Aam Aadmi Party leader Saurabh Bharadwaj criticised the BJP-run Delhi government on Thursday and raised questions over the reliability of CPCB's AQI data. Speaking to ANI and citing a report by the Centre for Research on Energy and Clean Air (CREA), Bharadwaj alleged that the pollution levels shown on government websites were 49% lower than the actual figures. He termed this discrepancy as a fraud on the population of Delhi. Bharadwaj claimed that if the AQI is 370, it could be 560 or more. He also questioned how CPCB deals with readings above 999, as their measurement system cannot record values above that level.

According to the ANI report, CREA found that in the analysis of hourly PM2.5 data from 59 monitoring stations in Delhi, 255 hours of records were missing between 4 pm on 8 November and 4 pm on 9 November. The analysis also noted that the 24-hour average PM2.5 concentration had increased from 269 to 400 micrograms per cubic metre, showing an increase of almost 49%. Bharadwaj used these findings to allege the difference between the recorded and officially displayed pollution levels.

The Central Pollution Control Board (CPCB) is a statutory institutional framework under the Government of India that sets and regulates standards to prevent air, water, and land pollution.