The Commission for Air Quality Management (CAQM) on Saturday said, the national Capital region recorded an average Air Quality Index (AQI) of 167 from January 1 to September 30 this year, the second-best for the corresponding period in six years.

Better air quality during this period was recorded only during the pandemic-affected 2020, it said in a statement. The daily avg. AQI for Delhi in the above noted period during the current year has been recorded as 167 as against 184 in 2022, 180 in 2021,  188 in 2019 and 193 in 2018 respectively, during the corresponding periods.

Delhi experienced its only "good" air quality day of the year, with an AQI of 45, on September 10, the final day of the G20 Summit. Despite less rainfall in September 2023 (82.7 mm) compared to September 2022 (165 mm), the average AQI for the month this year (108) remained on par with last year (104).

The month of September, 2023 also witnessed the only   “Good” air quality day  (AQI -45) of  the year on 10th September, 2023, co-incidentally on the  final day of the G20 Summit in New Delhi.

AQI is greatly impacted by the levels of rainfall/ precipitation and wind speed. September 2023 recorded a lower   rainfall of  total 82.7 mm as against 165 mm during the month of September, 2022.  Despite this deficit of rainfall, the daily avg. AQI during the month of September, 2023 at 108, has been comparable with the daily avg. AQI of 104 during September, 2022.

Delhi witnessed highest number of days (193) with “Good” to “Moderate” air quality (Daily Average AQI<200) during January – September 2023 as compared to the corresponding period for last 5 years (barring the COVID affected 2020).

“Good” to “Moderate” air quality days during this period in the previous years were only 146 in 2022, 174 in 2021, 165 in 2019 and 152 in 2018 respectively. This period in 2023 has also witnessed a remarkable reduction in daily avg. PM2.5 and PM10 concentrations over the last 6 years.

The CAQM said there has been a substantial reduction in daily average PM2.5 and PM10 concentrations in 2023 compared to the past six years.

In the first eight months of 2023, the daily average PM2.5 concentrations were around 73 micrograms per cubic metre, significantly lower than the range of 82-95 micrograms per cubic metre observed during the 2017-2022 period (excluding 2020). Similarly, the average PM10 concentration in Delhi this year averages 169 micrograms per cubic metre, lower than the range of 183-215 micrograms per cubic metre in the previous years (excluding 2020).

“Favourable meteorological conditions, continual ground level efforts, actions by various stakeholder agencies to abate air pollution and ongoing monitoring and enforcement actions have helped to better air quality during 2023. The Commission further urges all agencies and stakeholders to effectively implement the directions / guidelines related to abatement of air pollution and the citizens to follow the Citizen Charter in this regard, in our collective pursuit for better air quality during the ensuing winter season,” it said.