Delhi Records Cleanest Air In Nearly A Decade, Says CAQM Data
Delhi is experiencing its cleanest air stretch in almost ten years, according to official data, with air quality from January to September 2025 showing marked improvement compared to previous years—except during the extraordinary Covid lockdown period. Figures released by the Central Pollution Control Board (CPCB) reveal that the Capital’s average Air Quality Index (AQI) for the first nine months of this year has been the best since 2018, offering residents rare relief from the toxic skies that typically blanket the city. The Commission for Air Quality Management (CAQM), while presenting the data on Wednesday, attributed the cleaner air to a combination of favourable weather conditions and ongoing regulatory measures. “The improving trend in the overall air quality of Delhi-NCR continues and for the period between January–September this year, Delhi registers its best-ever average AQI during the eight years from 2018 to 2025, excluding 2020,” CAQM said in its statement. Numbers Show a Clear Shift Between January and September 2025, Delhi’s average AQI stood at 164—an improvement over 178 in 2024, 167 in 2023, and 193 in 2018. Only the pandemic year of 2020, when restrictions led to a sharp drop in emissions, recorded a lower level at 144. Officials noted that data from 2016 and 2017 were excluded due to inconsistencies, while 2020 was left out since its numbers reflected an “extraordinary halt in activity” rather than long-term progress. The Capital also logged its cleanest monsoon quarter in years. From July to September 2025, Delhi’s average AQI was 91—the lowest since 2018 (excluding 2020). By comparison, the figure stood at 103 in 2023, 95 in 2022, and 109 in 2018. Weather Gave Delhi a Breather Meteorologists say the weather played a decisive role in this year’s cleaner air. Unlike previous winters, January 2025 was marked by relatively high minimum and maximum temperatures, which helped disperse pollutants instead of trapping them close to the ground. “The summer this year was not as intense, with no heatwaves recorded,” explained Anumita Roychowdhury, executive director at the Centre for Science and Environment to media. “Additionally, we experienced frequent and intense spells of rain during the monsoon, which regularly washed away pollutants. Meteorological factors were definitely responsible for better air quality. How much the pollution level bounces back in the winter months is very important this year.” Thanks to these conditions, Delhi recorded no ‘severe’ or ‘severe-plus’ air days till September—compared to three such days each in 2024 and 2023, six in 2021, and seven in 2019. The city also registered its highest number of “satisfactory” days—75—since 2018, barring the exceptional 95 days recorded in 2020. In comparison, there were only 66 such days in 2024 and 53 in 2018. Fragile Gains Ahead of Winter Levels of PM2.5 and PM10, the harmful fine particles linked to severe respiratory illnesses, were also at their lowest in the first nine months of 2025 compared to the same period over the past seven years (again, with 2020 as the exception). Yet experts warn that these gains remain precarious. Historically, Delhi’s air quality plunges toward the end of the year, as colder weather traps pollutants, stubble burning in neighbouring states intensifies, and festive fireworks worsen the haze. For now, however, Delhiites are experiencing something rare—a sustained spell of cleaner air.
