Delhi's Air Quality Plummets, Raising Concerns Over Underreporting

On October 30, 2025, Delhi's air quality index (AQI) spiked by almost 100 points, from 279 to 373, over a 24-hour period. This sharp increase in pollution levels has raised concerns about the accuracy of air quality monitoring in the city.

According to the analysis, the spike in AQI could be attributed to both a genuine increase in pollution and potential underreporting of the index on October 29. Satellite imagery and modeled estimates of pollution suggest that the spike recorded on October 30 was much larger than the forecasts, particularly in the early hours of the day.

Residents of Delhi have also reported a visibly dense haze in the city for the past three to four days, contradicting the relatively lower AQI readings of 294 and 279 on October 28 and 29, respectively. This discrepancy between the official data and the perceived air quality has further fueled doubts about the reliability of the air quality monitoring system.

The article notes that while the spike in air pollution on October 29-30 does not conclusively prove measurement issues with India's AQI data, it does lend credence to the concerns expressed by Delhi residents about the air quality in the city. The situation highlights the need for a more robust and transparent air quality monitoring system to ensure accurate reporting and effective measures to address the city's persistent air pollution problem.