Stubble burning accounted for 32 per cent of Delhi's PM2.5 pollution (File)
The air quality in Delhi and nearby areas turned "severe" on Diwali as people defied a ban on lighting firecrackers in several areas, compounding the pollution cause by burning farm waste in neighbouring states.
Stubble burning accounted for 32 per cent of the city's PM2.5 pollution and calm winds worsened the situation, allowing the accumulation of pollutants, weather officials said.
The Ministry of Earth Sciences' air quality monitor, SAFAR, said, "Even a small increase in local additional emissions is likely to have significant deterioration impact on Sunday and Monday."
It said peak levels of PM10 and PM2.5 are expected between 1 am and 6 am in case of additional internal emissions.
The city recorded an overall Air Quality Index or AQI of 414 on Saturday, which falls in the "severe" category.
The 24-hour average AQI was 339 on Friday and 314 on Thursday.
Delhi recorded a 24-hour average AQI of 337 on Diwali last year (October 27), and 368 and 400 in the next two days. Thereafter, pollution levels remained in the "severe" category for three days.
This time, the India Meteorological Department has said that a fresh western disturbance could increase the wind speed and improve the air quality in Delhi-NCR after Diwali.
Light rain is likely on Sunday under the influence of a western disturbance. It is still unclear if it is enough to wash away pollutants, Kuldeep Srivastava, the head of the IMD's regional forecasting centre, said.
V K Soni, the head of the IMD's environment research centre, said calm winds, smoke from farm fires and firecrackers emissions may push the air quality to the "severe" zone on Diwali night.
The National Green Tribunal (NGT) had on Monday imposed a total ban on sale or use of all kinds of firecrackers in the National Capital Region (NCR) from November 9 midnight to November 30 midnight, saying "celebration by crackers is for happiness and not to celebrate deaths and diseases".
A bench led by NGT Chairperson Justice Adarsh Kumar Goel clarified that the direction will apply to all cities and towns in the country where the average of ambient air quality during November 2019 was in "poor" and above categories.
(With inputs from PTI)
