The air quality in Delhi-NCR improved markedly on Wednesday from "severe" to "very poor" towards the evening, with the wind speed catching up.
According to the environment authority, the wind speed on Wednesday increased while light showers at some places across Delhi-NCR helped to improve the overall ambient air quality of the region.
At 8 p.m. on Wednesday, the average air quality of Delhi and Delhi-NCR was "very poor" with the volume of major pollutant PM2.5, or particles with diameter less than 2.5 micrometers, 131 units in Delhi and 129 units in Delhi-NCR -- five time the safe limit.
However, on Tuesday the situation was severe with at least 11 out of 21 active monitoring stations falling under "severe" and "severe plus or emergency" category, while the PM2.5 in Delhi was 254 units and in Delhi-NCR it was 261 units -- 10 times the safe limit.
According to the Central Pollution Control Board (CPCB) at 4 p.m. on Wednesday the Air Quality Index of Delhi was 282 (poor) against 378 (very poor).
"The wind speed has increased on Wednesday and also the air quality has improved due to some showers here and there across NCR," Shambahvi Shukla, a researcher at the Centre for Science and Environment and member of the EPCA told IANS.
According to the India Meteorological Department, the wind speed would vary between 6 to 9 kmph.
"The air quality would remain the same, that is very-poor, on Thursday as well," Shukla added.
Meanwhile, the air quality in Anand Vihar area in east Delhi, Vasundhara in Ghaziabad and Sector 125 in Noida -- both in Uttar Pradesh -- came out of "severe plus or emergency" category to "very poor" on Wednesday for the first time in a month.