Delhi's PM2.5 levels hit a peak by midnight on Diwali this year, which was 13% higher than the peaks observed last year and in 2022, a recent analysis by the Centre for Science and Environment (CSE) showed. “The Diwali night this year had higher nitrogen dioxide (NO2) levels that indicate high traffic congestion,” the CSE report said.
Centre for Science and Environment (CSE). The elevated pollution was largely attributed to a combination of firecracker usage, increased traffic ...
Two days after Diwali, Delhi’s Air Quality Index (AQI) worsened, crossing 500 and reaching the ‘Hazardous’ level. As of 5 am, the AQI stood at 507, with thick smog covering the city. According to IQAir data, PM2.5 levels in Delhi-NCR are now over 65 times higher than WHO’s safe limit. According to reports, Delhi’s AQI soared from 327 to 507 within 12 hours. At 9 p.m. on Saturday, Delhi’s AQI was recorded at 327 in most areas. A thick layer of smog engulfed the national capital, and the AQI was recorded at 507. According to the IQAir website data, Delhi-NCR’s PM2.5 levels were over 65 times more threatening than the WHO-prescribed limit. Meanwhile, Delhi Environment Minister Gopal Rai said that around 200 mobile anti-smog guns will be deployed across the national capital to combat dust pollution. Speaking to ANI on Saturday, Gopal Rai said that the Delhi government is continuously working on the ground to combat the rising pollution levels. He further said that to address dust pollution, the Delhi government will deploy 200 mobile anti-smog guns throughout the city, which will operate in three shifts of eight hours each, spraying water in every assembly constituency to help control dust levels. An analysis by the Centre for Science and Environment has drawn attention to the season’s first smog—on Diwali day. It also said that the PM2.5 concentration this Diwali was 34% higher than in 2022, despite both occurring in October. The study said that by midnight on October 31, PM2.5 hit a peak of 603 micrograms per cubic metre, 13% higher than Diwali peaks recorded in both 2022 (when Diwali occurred on Oct 24) and 2023 (Nov 12).
NEW DELHI: The national capital's PM2.5 levels hit a peak by midnight on Diwali this year, which was 13 per cent higher than the peaks observed last year and in 2022, a recent analysis showed. The Diwali night this year had higher nitrogen dioxide (NO2) levels that indicates high traffic congestion, a report by Centre for Science and Environment (CSE) said. The research organisation's report also said unlike previous years, on Diwali night in Delhi, there was a quick build-up of PM2.5 levels and dissipation the next day.
Good weather conditions helped ease the pollution levels in Delhi after Diwali. Despite extensive use of fireworks and increased stubble burning, the city's air quality did not enter the "severe" category. Wind speeds reaching up to 16 km/h and higher-than-normal temperatures kept the Air Quality Index (AQI) in the "very poor" range, resulting in the second cleanest post-Diwali day since 2015 as reported by TOI. AQI peaked at 362 on Friday morning but gradually improved to 354 by noon, with an average AQI of 339 for the day. In a TOI report, Anumita Roychowdhury from the Centre for Science and Environment (CSE) attributed the improvement to warmer conditions and reasonable wind speed.
Delhi's air quality has been the second cleanest post-Diwali since 2015, maintaining a “very poor” Air Quality Index (AQI) instead of deteriorating to “severe". This stability is credited to “strong wind ventilation", with speeds reaching 16 kilometres per hour. While the 24-hour air quality index (AQI) climbed steadily through Thursday night — from 328 in the early evening to 338 at midnight, reaching 362 by 9am Friday — the city experienced an unexpected respite. Strong, sustained winds swept through Delhi, rapidly dispersing the dense smoke layer and bringing the AQI down to 339 by 4pm Friday, further improving to 323 by 7pm. The use of fireworks, an increase in stubble burning, and emissions from various local sources that release toxic gases pushed the city’s air quality into the upper range of “very poor” late Thursday night and into Friday morning. Mahesh Palawat, vice president at Skymet meteorology, explained this complex interaction between temperature and pollution: “Higher temperature keeps mixing height high and allows pollutants to move and disperse freely. Low temperature slows down wind speed and also traps pollutants closer to the surface through a phenomena called inversion.” He noted that while winter months typically see the mixing height drop to a mere 200-300 metres, Thursday maintained mixing height of 2,100 metres. “Even though the air quality on Diwali was in the very poor category — hitting severe levels during midnight — these conditions dissipated quickly the next day to reach moderate levels by the afternoon. This is mainly because of relatively warm conditions with reasonable wind speed and natural ventilation. The deep calm winter inversion conditions are yet to set in. Despite this, the month of October has also seen more poor and very poor days than previous years, even when the contribution of farm fires has been just around 1-3%, indicating a very high impact of local and regional pollution,” Anumita Roychowdhury, executive director, Research and Advocacy at the Centre for Science and Environment (CSE) told The Times of India.
Delhi’s air quality worsens every Diwali but this year it has reached the ‘very severe’ category a day prior to the festival of lights. The government conveniently blames these high pollution levels on stubble burning by farmers of Punjab and Haryana but in a report released on Wednesday, the Centre for Science and Environment has come up with hard data to show that the contribution of farm fires to the rising PM2.5 levels in the capital region has been 16 per cent. Delhi's 1.3 crore vehicles are primarily responsible for this pollution spike, especially because of the massive congestion on main arterial roads. The cities on the periphery of the capital such as Faridabad, Ghaziabad, Gurgaon, and Gautam Buddh Nagar must also take their share of the blame. The unrestricted use of firecrackers, despite the ban imposed by the Supreme Court, has muddied our air even further. It has been stated ad nauseam that 22 out of the world’s 30 most polluted cities are in India with Ghaziabad enjoying the dubious distinction of being the most polluted. Let’s face it. Our cities are in a royal mess. A Niti Aayog report says that nearly 70 per cent of India’s water is contaminated, especially that coming from our main rivers. Waterborne diseases are rampant and we continue to have more than 1.5 million children succumbing annually to diarrhoea. The water supplied in our cities is sub-standard with its quality is known to deteriorate as the water travels through the trunk mains to service reservoirs. The Economist Intelligence Unit’s 2022 “Global Liveability Index,” which looks at healthcare, environment, education, and infrastructure in 173 cities around the world, highlights. New Delhi is ranked 140, Mumbai 141, Chennai 142, Ahmedabad 143 and Bengaluru 146. This is all the more shocking because just 25 years ago, Bengaluru and New Delhi were considered “garden cities’ with a pleasant ambience that its residents found extremely endearing. Our hill stations were amongst the most beautiful and salubrious but all that has changed as these too have metamorphosed to become concrete jungles.
NEW DELHI: Good weather spared Delhiites a “severe” punishment a day after Diwali as widespread use of fireworks, a spike in the share of stubble burning, and emissions from other local sources releasing toxic gases pushed the city’s air quality into the upper level of “very poor” late Thursday night and Friday morning. High ventilation by winds of up to 16km/h and above-normal temperatures kept AQI within the “very poor” range, making it the second cleanest post-Diwali day since 2015. festivals With clear skies, the day after Diwali was good in comparison to years like 2020 and 2021 — when air quality had plummeted to severe — and even last year, when AQI was 358. However, despite favourable conditions and lack of winter chill, post-Diwali 2024 still managed to spill a toxic cocktail of pollutants into the air. On Thursday, while some areas of south Delhi refrained from bursting crackers on a mass scale, the majority of the city made up for it. A spike in the share of stubble burning in the city's PM2.5 level also made a difference, with the share of stubble burning soaring to 27.61% on Diwali day (Thursday), compared to 8.4% on Wednesday and 1.8% on Tuesday. AQI peaked at 362 at 9am on Friday morning as the pollution load kept increasing until that time. However, after that, it gradually improved. By noon, it had improved to 354 on Friday, while the day’s average AQI was 339 against 328 on Thursday. how delhi "Even though the air quality on Diwali was in the very poor category — hitting severe levels during midnight — these conditions dissipated quickly the next day to reach moderate levels by the afternoon. This is mainly because of relatively warm conditions with reasonable wind speed and natural ventilation. The deep calm winter inversion conditions are yet to set in. Despite this, the month of October has also seen more poor and very poor days than previous years, even when the contribution of farm fires has been just around 1-3%, indicating a very high impact of local and regional pollution,” said Anumita Roychowdhury, executive director, Research and Advocacy at the Centre for Science and Environment (CSE). Friday morning also turned hazy, which cleared with the winds and sun. According to the weather department, the wind speed was between 12- 16km/h until midnight on Diwali, which dropped to 3-7 km/h towards midnight but increased again on Friday morning, helping with ventilation and dispersal of pollutants. However, even as post-Diwali AQI 2024 turns out to be the second cleanest since 2015, what's concerning is the hourly spike in PM2.5 levels in some areas, which, as per the DPCC, spiked to more than 30 times the national permissible limits. "In addition to pollution from firecracker bursts, stubble burning incidents in Punjab are on the rise, signalling that post-harvest burning is ramping up and will likely exacerbate pollution in DelhiNCR over the next two weeks. Immediate intervention from authorities is crucial to manage this issue," stated Sunil Dahiya, founder and lead analyst, Envirocatalysts. According to Abhishek Kar, senior programme lead, Council on Energy, Environment and Water (CEEW), while the wind speeds reaching over 2m/s between 7am and 4pm on Friday helped the city, the air quality is yet to see a breather. "The air quality will remain an issue in the coming days due to an increase in stubble burning in the upwind states of Punjab and Haryana. According to the AQEWS, the AQI for the next seven days is expected to be consistently above 350 and will occasionally breach the 400- mark,” said Kar.
India’s national capital and its surroundings were engulfed by a toxic haze and the acrid stench of smoke on Thursday night as a large number of revellers violated a ban on firecrackers and police looked the other way to inflict on their fellow citizens a public health crisis that would have turned far more toxic had it not been a providential strengthening of winds on Friday that helped blow the smoke away. Across the national capital region (NCR), what began as a staccato of pops and bangs in the late evening turned into a crescendo of whistling rockets, thunderous aerial explosions and relentless smoke-spewing sparks of anars and charkhis that went on well past midnight. The air quality index (AQI) at 4pm before the celebrations began on Thursday was at 328, classified “very poor”, and held steady till about 9pm after which it began steadily worsening: 330 at 10pm, 338 at midnight, 347 at 3am on Friday and 362 at 9am.Post 9am, the AQI began improving and was 354 by noon, 339 by 4pm and 314 by 10pm. But these figures were all 24-hour averages. In real time, PM2.5 levels in the city shot up by a staggering 15 times in some parts of the city, reaching as high as over 1,800 µg/m³ in certain residential areas. The World Health Organization sets the safe limit of PM2.5 exposure at 15µg/m³ India’s National Ambient Air Quality Standards sets it at 60µg/m³. By Friday afternoon, the worst of the pollution appeared to have been swept away by strong winds and warm temperature, an unusual set of meteorological circumstances for this time of the year but one that meant the city of 20 million caught a lucky break. “We had steady winds throughout Diwali day and on Friday too. Wind speed was 12-16 km/hr till 6 pm on Thursday. It dipped marginally, but remained between 3 and 7 km/hr through the night and again picked up to around 10 km/hr when the sun came out on Friday,” said an India Meteorological Department official, who asked not to be named, while another climate expert described this improvement as nothing but “getting lucky with the weather”. It was not merely the sights and sounds of Thursday night that illustrated the brazen flouting of the firecracker ban. HT’s analysis of real-time pollution monitoring data shows in granular detail how concentrations of PM2.5, ultrafine particulates that mostly make up smoke, shot up in the evening: At the Nehru Nagar station, abutting Lajpat Nagar, hourly average PM2.5 concentration rose from 101 µg/m³ to a whopping 898 µg/m³ at 11pm, or a nearly nine-fold increase. At Anand Vihar, next to the residential settlements of Vivek Vihar, the peak 1am was 992 µg/m³, over seven times the 135 µg/m³ recorded at 6pm. In instant readings, these numbers reached even more alarming figures: 1,853 µg/m³ at Vivek Vihar and 1,527 µg/m³ at Nehru Nagar. That these spikes were due to firecrackers is clear when one takes into account readings at Narela and Najafgarh, both industrial zones that were empty as people went back home to celebrate Diwali. At Najafgarh, the peak was roughly 247 µg/m³ and in Narela, around 260 µg/m³ -- both these stations recorded 80-90 µg/m³ in the evening, which made the increase the most moderate seen across the city. India classifies the safe limit for PM2.5 exposure to be no more than 60 µg/m³. Other data too suggested there was widespread violation of the firecracker ban. The Delhi Pollution Control Committee (DPCC) said of its 31 ambient noise monitoring stations, 22 recorded higher decibel levels this Diwali compared to last year. The highest decibel levels this Diwali were recorded at central Delhi’s Karol Bagh – an average of 88.7 dB (A), around 5% higher than the average reading of 84.5 dB (A) recorded last Diwali. The Delhi Fire Services too said it received the highest number of calls -- 280 -- for fire-related incidents since records were kept beginning 2012. The defiance of the firecracker ban raised questions about the effectiveness of environmental regulations in a city consistently ranked among the world’s most polluted capitals. An environment department official when contacted, said enforcement of the ban lay with the Delhi Police. “We appealed to people to not burst crackers and to report instances on 112 and 1090. The Police was then responsible for taking suitable action,” the official added. The Delhi Police did not comment on the mass violation of the firecrackers ban. HT sent messages to several senior police officers, including the spokesperson of Delhi Police and deputy commissioners of police (DCPs) of all 15 police districts, seeking data and their response on action taken against violation of the firecrackers ban. They did not respond till the time of going to print. What helped, then, was simply the weather. “We got lucky, in the sense that we have seen this in some previous years when wind speed has been low and the pollutants hang in the air for several days. If winds are strong, pollution disperses within a matter of hours and then you again have local sources adding to the pollution,” said Mahesh Palawat, vice president at Skymet meteorology, forecasting similar wind speed for Saturday, but a drop on Sunday. Environmental experts pointed out that relying on favourable weather conditions is a dangerous gamble. “October being a warmer month and Diwali day recording reasonably good wind speed, the pollution levels on Diwali night that build up to severe levels, did not last very long,” said Anumita Roychowdhury, executive director, research and advocacy at the Centre for Science and Environment (CSE), pointing out that peak pollution levels on Diwali night were in fact in the severe range.
As Delhi's air quality deteriorated further thanks to the relentless bursting of firecrackers despite a ban to celebrate Diwali, its neighbouring state, Punjab, on Thursday reported 484 stubble-burning cases. This is the highest number of cases in a single day in 2024. According to data from the Punjab Pollution Control Board (PPCB), the total number of stubble-burning cases in the state this year has now reached 2,950. Out of all the districts in Punjab, Sangrur reported 89 cases of stubble burning, the highest number on Thursday. Following Sangrur, Ferozepur reported 65 cases, whereas Mansa reported 40 cases. This year, Amritsar has reported the maximum number of cases at 529, whereas Tarn Taran has recorded 444 cases. Sangrur has recorded 348 cases. The Sangrur administration is taking stringent action against officials who were not able to avoid such incidents, a Hindustan Times report said, citing Sandeep Rishi, deputy commissioner of Sangrur. The district has reported 147 incidents of stubble burning in the last three days. The administration has suspended eight officials and registered cases against three employees under section 14 of the Commission for Air Quality Monitoring (CAQM) Act. Additionally, a letter has been written to higher officials to their departments to suspend three other officials, the report added. The state has observed a rise in stubble-burning cases due to paddy harvesting and burning of crop residue. Other districts such as Patiala, Ferozepur and Mansa have been witnessing a rising number of farm fire incidents in the last few days. Meanwhile, Delhi’s air quality has dropped from ‘poor’ to ‘very poor’ mainly due to local pollution sources, according to a PTI report citing an analysis by the Centre for Science and Environment (CSE). As per the analysis, farm fires have contributed only 4.44 per cent to Delhi’s air quality level whereas local sources have contributed over 95 per cent. The transport sector contributes more than half to Delhi’s air quality level, residential burning contributes nearly 13 per cent, industrial emissions account for 11 per cent and construction activities provide around 7 per cent. "This year, the air quality has worsened even though the contribution of farm fires has remained significantly lower than previous years," the report quoted Anumita Roychowdhury, executive director of research and advocacy at the CSE as saying.
In a surprising reprieve, favourable weather conditions shielded Delhiites from “severe” pollution levels a day after Diwali, despite widespread firecracker use and an uptick in stubble burning, both of which pushed the city’s air quality into the upper bounds of the “very poor” category on Thursday night and Friday morning. A combination of brisk winds reaching up to 16 km/h and above-normal temperatures helped mitigate the pollution, marking the second cleanest post-Diwali day since 2015. This year’s Diwali conditions showed improvement compared to severely polluted post-Diwali periods in 2020 and 2021. While the average air quality index (AQI) on Diwali day was 328, it spiked to 362 by Friday morning but later subsided to a daily average of 339, as natural ventilation helped dilute pollutants. According to the Delhi Pollution Control Committee (DPCC), some areas of south Delhi experienced less cracker activity on Thursday, yet pollution remained high due to increased firecracker use across the rest of the city. The share of stubble burning in the city’s PM2.5 pollutant load also saw a significant jump, reaching 27.61% on Diwali day compared to 8.4% the previous day and just 1.8% on Tuesday. "Even though the air quality on Diwali was in the very poor category — hitting severe levels during midnight — these conditions dissipated quickly the next day to reach moderate levels by the afternoon. This is mainly because of relatively warm conditions with reasonable wind speed and natural ventilation. The deep calm winter inversion conditions are yet to set in," Anumita Roychowdhury, executive director, Research and Advocacy at the Centre for Science and Environment (CSE), was quoted as saying in a Times of India report. "Despite this, the month of October has also seen more poor and very poor days than previous years, even when the contribution of farm fires has been just around 1-3%, indicating a very high impact of local and regional pollution,” Anumita added. Early Friday morning brought hazy skies, but these cleared by noon as wind speeds rose, helping to ventilate the city. The India Meteorological Department reported that while wind speeds fell to 3-7 km/h toward midnight on Diwali, they picked up again the next morning, aiding in dispersing the pollution load. However, environmental experts warn that while the capital experienced moderate relief on Friday, the rise in stubble burning incidents in neighboring Punjab is likely to exacerbate air quality issues in the coming days. Sunil Dahiya, founder of Envirocatalysts, highlighted the urgency of government intervention, as PM2.5 levels in some areas exceeded 30 times the national permissible limits. Abhishek Kar, senior program lead at the Council on Energy, Environment and Water (CEEW), emphasized that this short-term improvement might not hold up as stubble burning continues. "The air quality will remain an issue in the coming days due to an increase in stubble burning in the upwind states of Punjab and Haryana. According to the AQEWS, the AQI for the next seven days is expected to be consistently above 350 and will occasionally breach the 400- mark,” Kar told TOI.
दिवाली के साथ-साथ नई दिल्ली में प्रदूषण पर भी चर्चा बढ़ जाती है. दिवाली के अगले दिन खबरों में दिल्ली के बढ़े AQI लेवल पर बहस तेज हो जाती है. लेकिन इस बार दिवाली के अगले दिन प्रदूषण स्तर पिछले साल के मुकाबले कम रहा है. अगर 2022 को छोड़ दिया जाए, तो 2015 के बाद से ये सुबह दिवाली के अगले दिन की सबसे साफ सुबह थी. केंद्रीय प्रदूषण नियंत्रण बोर्ड (CPCB) के आंकड़ों के मुताबिक, दिवाली के बाद 24 घंटे का औसत वायु गुणवत्ता सूचकांक (AQI) शुक्रवार को 339 था, जो 2023 में दिवाली के अगले दिन (13 नवंबर) 358 से बेहतर है. दिवाली के बाद सबसे खराब वायु गुणवत्ता वाला दिन 2021 में दर्ज किया गया, जिसमें AQI 462 था. इस बार क्यों कम रहा प्रदूषण? प्रदूषण के कम रहने के कई कारण, लेकिन इसमें सब से अहम इस समय का मौसम है. पिछले साल दिवाली नवंबर में मनाई गई थी और इस समय तापमान काफी ठंडा था. पिछले साल नवंबर का न्यूनतम तापमान 13 डिग्री सेल्सियस और अधिकतम 27.8 डिग्री सेल्सियस दर्ज किया था. जबकि इस साल दिवाली अक्टूबर के आखिर में मनाई गई है और इस समय मौसम पहले के मुकाबले काफी गर्म है. IMD के मुताबिक इस साल का अक्टूबर पिछले 73 सालों में सबसे गर्म अक्टूबर रहा है. दिल्ली के सफदरजंग मौसम केंद्र में अक्टूबर में दर्ज किए गए अधिकतम और न्यूनतम औसत तापमान क्रमशः 35.1 डिग्री सेल्सियस और 21.2 डिग्री सेल्सियस था. ये आंकड़ा दिल्ली में 1901 के बाद से महीने में दर्ज किया गया चौथा सबसे ज्यादा तापमान है. दरअसल जब तापमान ठंडा होता है, तब हवा में एक परत जम जाती है. जिसकी वजह से प्रदूषण वायुमंडल की ऊपरी परत में नहीं फैलता और नीचे ही रहता है. हवा भी रही जिम्मेदार प्रदूषण कम रहना का दूसरा कारण है तेज हवाएं. तेज हवाओं के चलने से प्रदूषण का बेहतर ढंग से फैलाव हुआ और प्रदूषित हवा एक जगह नहीं ठहरी. तेज हवाओं के कारण PM2.5 और PM10 जैसे छोटे प्रदूषकों का स्तर, जो गुरुवार को पंजाब और हरियाणा में पराली जलाने और पटाखे फोड़ने की वजह से बढ़ गया था, वो अगले दिन कम हो गया. सेंटर फॉर साइंस एंड एनवायरनमेंट में रिसर्च एंड एडवोकेसी की एग्जीक्यूटिव डायरेक्टर अनुमिता रॉय चौधरी ने ‘इंडियन एक्सप्रेस’ को बताया, इस बार दिवाली अक्टूबर में थी, मौसम में ठंडक अभी तक नहीं आई है. दिवाली की रात के बाद प्रदूषण को कम करने के लिए हवा की गति भी अनुकूल थी. दिवाली के दिन दोपहर तक हवा की गुणवत्ता ‘खराब’ रही और फिर शाम को ‘बहुत खराब’ हो गई. आधी रात को गंभीर AQI स्तर देखा गया और कई स्टेशनों पर सुबह 7 बजे तक बना रहा. दिवाली से रात के समय PM2.5 के स्तर में बहुत बढ़ोतरी देखी गई. इसमें पटाखों का योगदान कितना था, ये नहीं बता सकते क्योंकि कई और फैक्टर इस बढ़ोत्तरी में शामिल हैं. 2 नवंबर को दिल्ली के अलग-अलग इलाकों में कितना रहा AQI सेंट्रल पॉल्यूशन कंट्रोल बोर्ड के ऐप समीर के मुताबिक आज यानी शनिवार को दिल्ली का AQI 298 है. ये आंकड़ा सुबह 6 बजे का है. अलीपुर 301 आनंद विहार 382 अशोक विहार 331 बवाना 319 बुराड़ी 318 चांदनी चौक 301 द्वारका सेक्टर 8 310 पंजाबी बाग 339 आरकेपुरम 346 रोहिणी 311 सोनिया विहार 328 विवेक विहार 322 वजीरपुर 325
सेंटर फॉर साइंस एंड एनवायरनमेंट की एक रिपोर्ट के अनुसार, दिल्ली में स्थानीय स्रोतों से निकलने वाले प्रदूषण में सबसे बड़ा योगदान वाहनों से निकलने वाले धुओं का है, जो कुल प्रदूषण का आधे से ज्यादा है। इसके बाद आवासीय जलन से 13 प्रतिशत, उद्योग से 11 प्रतिशत, निर्माण से 7 प्रतिशत, ऊर्जा से 6 प्रतिशत, कचरा जलाने से 5 प्रतिशत, और सड़क की धूल और अन्य स्रोतों से 4 प्रतिशत योगदान है।
दिवाली के अगले दिन दिल्ली में वायु गुणवत्ता में उल्लेखनीय सुधार हुआ। अनुकूल मौसम स्थितियों के कारण दिल्ली की हवा "गंभीर" की श्रेणी में जाने से से बच गई। आतिशबाजी के बावजूद, वायु गुणवत्ता सूचकांक (AQI) "बहुत खराब" श्रेणी में रहा। 16 किमी/घंटा तक की गति से चलने वाली हवा और सामान्य से अधिक तापमान ने AQI को बेहतर बनाए रखने में महत्वपूर्ण भूमिका निभाई। जिसके चलते शहर में 2015 के बाद से दिवाली के बाद दूसरा सबसे साफ दिन रहा। सेंटर फॉर साइंस एंड एनवायरनमेंट (CSE) में रिसर्च एंड एडवोकेसी की कार्यकारी निदेशक अनुमिता रॉयचौधरी ने दिवाली के दौरान और उसके बाद वायु गुणवत्ता की गतिशील प्रकृति की ओर इशारा किया।
New Delhi: The air quality in Delhi remained within the "very poor" range on Friday morning despite widespread use of fireworks, and other factors like a spike in the share of stubble burning, and emissions from other local sources due to relatively warm conditions with reasonable wind speed and natural ventilation, according to experts. These factors contributed significantly in improving the air quality in city - which hit severe levels during midnight — to reach moderate levels by the afternoon next day, they said. "The deep calm winter inversion conditions are yet to set in. Despite this, the month of October has also seen more poor and very poor days than previous years, even when the contribution of farm fires has been just around 1-3%, indicating a very high impact of local and regional pollution,” said Anumita Roychowdhury, executive director, Research and Advocacy at the Centre for Science and Environment (CSE), according to Times of India.
Delhi experienced a rare respite from severe pollution levels the day after Diwali, aided by favorable weather conditions that helped disperse pollutants. Despite extensive firecracker use and an increase in stubble burning, the city’s air quality on Friday was the second cleanest post-Diwali day since 2015. Brisk winds up to 16 km/h and above-average temperatures played a crucial role in reducing pollution levels, with the air quality index (AQI) hitting 362 in the morning before dropping to an average of 339 by day’s end. Firecracker use across the city remained high, with pollution in some areas surging to severe levels by midnight. The contribution of stubble burning to Delhi’s PM2.5 pollutants also saw a jump, reaching 27.61% on Diwali compared to 8.4% the previous day. Experts from the Delhi Pollution Control Committee (DPCC) and the Centre for Science and Environment (CSE) noted that pollution levels were initially high but quickly reduced due to warm weather and moderate wind speeds. Anumita Roychowdhury from CSE observed that while October has seen more “poor” air quality days, this Diwali saw fewer severe conditions due to improved ventilation. However, environmentalists cautioned that the relief might be short-lived, as stubble burning incidents in Punjab are likely to worsen the air quality soon. Sunil Dahiya from Envirocatalysts warned that PM2.5 levels exceeded permissible limits in certain areas, and Abhishek Kar from the Council on Energy, Environment, and Water (CEEW) projected that Delhi’s AQI could rise above 350, with potential to exceed 400 in the days ahead as crop residue burning intensifies in neighboring states.