Delhi's air quality deteriorates as monsoon
Delhi's air quality index has worsened to 169, with dry weather and low winds contributing to the rise. The India Meteorological Department predicts the monsoon will withdraw from the city within days, ending a period of relatively clean air.
Delhi's air quality has deteriorated into the upper end of the moderate category, recording an Air Quality Index (AQI) of 169 on Monday afternoon. The India Meteorological Department (IMD) states conditions are now favourable for the withdrawal of the monsoon from the city within the next two to three days.
Dry weather and low wind speeds have contributed to the accumulation of pollutants. The main pollutants identified are PM2.5 and ozone. This marks the highest AQI reading since July 19, when it was 171.
A steady decline in air quality
The city's air quality has worsened steadily over recent days. According to the source report from the Hindustan Times, the AQI has climbed from 88 on Friday to 118 on Saturday, then to 160 on Sunday, before reaching 169 on Monday.
| Day | AQI |
|---|---|
| Friday | 88 |
| Saturday | 118 |
| Sunday | 160 |
| Monday | 169 |
The Central Pollution Control Board (CPCB) categorises an AQI between 101 and 200 as 'moderate'. The scale ranges from 'good' (0-50) to 'severe' (401-500).
Monsoon withdrawal and local hotspots
The IMD announced the southwest monsoon has already withdrawn from parts of Rajasthan, Haryana, and Punjab. Conditions are favourable for its further withdrawal from the remaining parts of Punjab, Haryana-Chandigarh-Delhi, Rajasthan and parts of Saurashtra & Kutch, Jammu-Kashmir, Himachal Pradesh, Uttarakhand and West Uttar Pradesh in the next two to three days, the department stated.
With the monsoon's retreat, no rain is expected in Delhi this week. The city recorded a maximum temperature of 35.6 degrees Celsius and a minimum of 25 degrees Celsius on Monday. The IMD forecasts the minimum temperature may fall gradually to 22-23 degrees Celsius by the weekend.
The deterioration is already evident at several monitoring stations. Eight of Delhi's 42 active stations recorded air quality in the 'poor' category (AQI 201-300) on Monday.
| Monitoring Station | AQI (Category) |
|---|---|
| Siri Fort | 221 (Poor) |
| Chandni Chowk | 221 (Poor) |
| IGI | 219 (Poor) |
| Burari | 215 (Poor) |
| Wazirpur | 213 (Poor) |
| Patparganj | 208 (Poor) |
| Narela | 207 (Poor) |
| IIT | 202 (Poor) |
End of a cleaner period
Delhi has experienced relatively clean air over the past month due to monsoon rains and strong winds. In September, the city recorded 12 'satisfactory' and eight 'moderate' air quality days.
The cleanest air day of the year so far was recorded on July 9, with an AQI of 48, which falls in the 'good' category. The last 'poor' air quality day before this week was on July 12, when the AQI hit 246. That brief deterioration was attributed to dust carried by winds from Afghanistan, Iran, and Pakistan towards northwestern India.
