Gurgaon: The city’s air quality deteriorated to the ‘poor’ category on Wednesday, a day after Dussehra, as the air quality index (AQI) rose to 216 (poor). Thousands had gathered across the city on Tuesday to witness Ravan dahan, while fireworks lit up the night sky.According to air quality monitoring data, the city’s AQI was 184 (moderate) on Tuesday and 132 (moderate) on Monday. This year’s post-Dussehra AQI was higher than the readings recorded on the day after the festival in each of the previous four years. In 2025, the AQI was 88 (satisfactory) on Oct 3, while it was 169 (moderate) on Oct 13 in 2024. The reading stood at 190 (moderate) in 2023 and 73 (satisfactory) in 2022. The city had recorded more polluted air in 2021, when the AQI reached 308 (very poor) on Oct 16, the day after Dussehra.The worsening air quality coincided with a drop in minimum temperature. According to India Meteorological Department (IMD) data, the city recorded a minimum temperature of 14 degrees Celsius on Wednesday, the lowest in Haryana. It was three degrees below normal and 0.6 degrees lower than the previous day.Three of the city’s four air quality monitoring stations reported data on Wednesday morning. Gwalpahari recorded an AQI of 233 and TERI Gram 205, both in the ‘poor’ category. Sector 51 recorded 175, which falls in the ‘moderate’ category.Air quality also worsened in Noida and Ghaziabad, with both cities recording ‘poor’ air on Wednesday. Noida’s AQI rose to 249 (poor) from 161 (moderate) on Tuesday and 138 (moderate) on Monday. Ghaziabad recorded 223 (poor), up from 202 (poor) on Tuesday and 175 (moderate) on Monday.The decline in air quality also came during the ongoing crop residue burning season in north India. Satellite-based monitoring data showed 1,265 farm-fire incidents across seven states between Sept 15 and Oct 20. These included 404 in Punjab, nine in Haryana, 187 in UP, one in Delhi, 215 in Rajasthan, 61 in Uttarakhand and 388 in MP. However, the available data did not establish the extent to which emissions from these fires contributed to Gurgaon’s pollution levels on Wednesday.Air quality across Delhi-NCR worsens every winter as falling temperatures and unfavourable meteorological conditions slow dispersal of pollutants. Emissions from vehicles, construction activities, road dust, waste burning and crop residue fires add to the region’s pollution load. Fireworks during festivals can also lead to short-term spikes in particulate pollution.The city’s pollution levels have fluctuated through Oct. CPCB data showed an AQI of 207 on Oct 2 and 201 on Oct 9, before the reading dropped to 89 (satisfactory) on Oct 16. It later rose to 159 (moderate) on Oct 18, dipped to 132 on Oct 19 and climbed to 184 on Oct 20.“The wind speed on the night of Oct 20 dropped to under 1 kmph occasionally, and throughout the day on Oct 21 it remained well below 10 kmph. Winds above 10 kmph are conducive for pollutant dispersion. Moreover, an uptick in the number of farm fires is being reported in northwest India. During this time of the year, the wind direction towards Delhi-NCR is predominantly northwesterly, and transports pollutants from farm fires. According to Delhi’s Air Quality Early Warning System, AQI is expected to be around 300 mark, owing to unfavourable winds. We are going to experience a strong El Nino winter, and according to an analysis by Council on Energy, Environment and Water (CEEW), meteorological conditions for pollutant dispersion are better during La Nina years,” said Mohammad Rafiuddin, programme lead, CEEW.Commission for Air Quality Management (CAQM) invoked Stage I of the Graded Response Action Plan (GRAP) across Delhi-NCR on Wednesday after Delhi’s AQI rose to 244 (bad) at 2pm from 179 on Tuesday. The commission said air quality was likely to remain in the ‘poor’ category over the next few days and directed agencies across the region to implement Stage I measures with immediate effect to prevent further deterioration.
