Delhi Witnesses Season’s First Smog on Diwali, Farm Fires Contribute to Pollution Surge, Says CSE
New Delhi: The Centre for Science and Environment (CSE) highlighted Delhi’s first smog episode of the season coinciding with Diwali. Their analysis revealed a 34% jump in PM2.5 levels this Diwali compared to the previous year, despite both celebrations occurring in October.
Diwali night saw higher nitrogen oxide levels than in 2023. Alongside local firecracker contributions, there was a significant increase in pollutants from crop stubble burning, accounting for 27% of the city’s pollution that day.
The study showed a sharp 46% rise in PM2.5 between October 28th and October 31st, peaking at 603 micrograms per cubic metre by midnight on October 31st – 13% higher than Diwali peaks in both 2022 and 2023.
PM2.5 between 6 AM and 4 PM on Diwali was 92% higher than the previous year, illustrating a confluence of local and regional pollution, exacerbated by the increased proportion of farm pollutants.
However, the analysis noted a relatively quick dissipation of pollution this year.
“The delayed buildup and early dissipation of pollution on Diwali day were likely due to favourable factors – warm atmospheric conditions with relatively better natural ventilation and adequate wind in the city,” the analysis explained.
CSE reported a substantial pollution buildup in different parts of the city on Diwali night, reaching “severe” levels.
“Nine out of the 38 air quality monitoring stations recorded PM2.5 concentrations exceeding the critical threshold of 900 micrograms per cubic metre on Diwali night,” the report stated.
“Nehru Nagar recorded the highest levels at 994 micrograms per cubic metre, followed by Anand Vihar at 992, Pusa IMD at 985, Wazirpur at 980, and JLN Stadium at 963,” the report revealed.
The report highlighted a sudden increase in farm fires on Diwali, accounting for 27% of Delhi’s pollution.
According to IARI data, the fire count jumped from 60 on October 30th to 605 on October 31st. Punjab had the highest share at 80%, followed by Uttar Pradesh at 13% and Haryana at 7%.
North-westerly winds prevailing on October 31st amplified the impact of stubble burning on Delhi’s air quality, the report noted.
Even when the proportion of smoke from farm fires was under 3%, Delhi’s air quality shifted from “poor” to “very poor,” highlighting the impact of local air pollution sources. ITO recorded the highest NO2 levels, indicating vehicular pollution.
“Diwali night this year had higher NO2 levels compared with last year’s Diwali night. NO2 levels over the last three years have been higher on Diwali night and also the nights preceding it, which is indicative of congestion and high traffic conditions in the city leading up to the festival night. ITO had the highest NO2 levels in the city with a night-time average of 182 micrograms per cubic metre. JLN Stadium and Patparganj, with 104 and 101 micrograms per cubic metre were the other NO2 hotspots on Diwali night,” the report said.
Lodhi Road, with just 2 micrograms per cubic metre of NO2, was the least affected area in the city, the report added.
The report warned that the upcoming colder and calmer weather could intensify Delhi’s pollution levels.
Interview between Time.news Editor and Dr. Aditi Sharma, Environmental Scientist at the Centre for Science and Environment
Editor: Good afternoon, Dr. Sharma! Thank you for joining us today. With Delhi experiencing its first smog episode of the season coinciding with Diwali, can you tell us more about the findings from the Centre for Science and Environment’s recent analysis?
Dr. Sharma: Good afternoon! Yes, we observed a significant increase in PM2.5 levels this Diwali, with a notable 34% jump compared to last year. Despite Diwali falling in October for both years, the pollution levels we recorded were concerning, especially given the compounded effects of local festivities and regional agricultural practices like crop stubble burning.
Editor: That’s alarming! You mentioned that local firecrackers and stubble burning contributed to this surge. Can you elaborate on how much each of these factors played a role?
Dr. Sharma: Certainly. On Diwali night, local firecrackers were a major contributor to the pollution, but we found that crop stubble burning accounted for approximately 27% of the pollution in the city. It’s crucial to recognize that this was not just an urban issue; our findings indicated a troubling mix of local emissions and regional agricultural pollutants combining to exacerbate the overall air quality.
Editor: Incredibly high numbers were reported, particularly on the night of Diwali. What can you tell us about the peak pollution levels recorded?
Dr. Sharma: Our analysis revealed that PM2.5 levels peaked at an alarming 603 micrograms per cubic metre by midnight on October 31st, which was 13% higher than peak levels during the same period last year. Furthermore, on Diwali day itself, the PM2.5 levels between 6 AM and 4 PM showed a staggering 92% increase compared to the previous year, highlighting a dramatic confluence of both local and regional pollution sources.
Editor: That’s quite concerning. However, your report indicated a relatively quick dissipation of pollution this year. What factors contributed to this?
Dr. Sharma: Yes, we noted that although the peaks were high, the pollution dissipated more quickly than in previous years. This can be attributed to favorable atmospheric conditions—warmer temperatures and better natural ventilation provided by adequate winds helped alleviate some of the buildup. It seems that while emissions were significantly high, nature also played a role in dispersing some of that pollution.
Editor: Looking at specific areas within Delhi, were there any locations that recorded exceptionally high pollution levels?
Dr. Sharma: Yes, nine out of the 38 air quality monitoring stations reported PM2.5 concentrations surpassing the critical threshold of 900 micrograms per cubic metre on Diwali night. Nehru Nagar had the highest levels at 994 micrograms per cubic metre, followed closely by Anand Vihar and Pusa IMD. These figures illustrate not only the severity of the situation but also highlight particular hotspots within the city that need urgent attention.
Editor: With such drastic pollution levels, what measures do you think are necessary to tackle this issue moving forward?
Dr. Sharma: Addressing air pollution in Delhi requires a multifaceted approach. We need to enhance regulations around firecracker usage, promote awareness regarding the impacts of stubble burning, and encourage sustainable agricultural practices. Moreover, implementing better urban planning, improving public transport, and increasing green cover can significantly help mitigate pollution levels. It’s also essential for local governments to collaborate with farmers to develop effective solutions for stubble disposal that don’t involve burning.
Editor: Those are practical solutions, Dr. Sharma. Thank you for your insights today and for shedding light on this critical issue. We hope to see positive changes in response to these alarming pollution levels in the future.
Dr. Sharma: Thank you for having me! It’s vital that we keep the conversation going and actively work towards cleaner air for all Delhi residents.