Pre-winter gas chamber? Delhi AQI more than doubles in 72 hours; pollution spikes at hotspots
New Delhi: Delhi’s air quality has deteriorated sharply over the past three days, even as winter is yet to set in. The national capital’s Air Quality Index (AQI) more than doubled from 90 on Friday to 187 on Sunday, according to data from the Central Pollution Control Board (CPCB).
The change comes as temperatures have started falling following the withdrawal of the monsoon. Delhi recorded a minimum temperature of 17.1 degrees Celsius on Sunday, 1.3 degrees below the seasonal normal, the IMD said. With no rainfall forecast over the coming week, pollution levels remain a concern.
The situation was particularly worrying at ITO where the AQI reached 430 on Sunday, placing it in the severe category. Meanwhile, 22 monitoring stations across Delhi recorded poor air quality, pointing to rising pollution levels in several parts of the city.
Why is Delhi’s AQI rising before Winter?
The recent deterioration follows a relatively cleaner reading on Friday, when Delhi’s AQI stood at 90. It rose to 159 on Saturday before reaching 187 on Sunday.
Dry weather, slower wind speeds and the absence of rainfall have contributed to the rise. Vehicle emissions, road dust and construction activity also add to pollution. Rain and stronger winds help disperse pollutants, but these natural cleaning conditions have weakened after the monsoon.
As winter approaches, cooler temperatures, stagnant winds and lower mixing heights can make it harder for pollutants to disperse, increasing the risk of further deterioration.
How Delhi’s pollution levels have changed
CPCB data also shows a rise in pollution at several locations since the start of October. On October 1, the AQI at ITO stood at 132 while Jahangirpuri recorded 216 and Punjabi Bagh 178. Anand Vihar, which often records high pollution levels, had an AQI of 96 that evening.
The CPCB classifies AQI readings of 101-200 as moderate, 201-300 as poor, 301-400 as very poor and 401-500 as severe.
What Delhi government says
Despite the recent spike, Delhi Environment Minister Manjinder Singh Sirsa said the city had recorded 211 days of good, satisfactory and moderate air quality so far this year. He described it as the best performance since 2016, excluding the COVID-affected year 2020.
Sirsa also said days with poor, very poor and severe air quality had fallen from 168 during the corresponding period in 2016 to 79 this year.
However, with the AQI rising and no rain expected in the coming week, Delhi faces fresh concerns over air pollution ahead of the winter season.