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Stubble burning not the only reason for Delhi air quality: CSE report

Delhi’s pollution level — or PM2.5 concentration — saw its first huge spike of the winter on 2 November with a sudden and staggering 68 per cent jump in 24 hours, crossing 313 microgram per cubic metre, which took it into the "severe plus" category, as per the air quality index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's air. Releasing the new analysis of the deadly winter pollution that has gripped Delhi-NCR, CSE executive director, research and advocacy, Anumita Roychowdhury said: "This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk.

GRAP temporary emergency measure, need enforcement of rules & penal action to tackle air pollution: Experts

There is nothing like a disaster to galvanise authorities and this is quite evident in Delhi-NCR where inadequate round-the-year action on the ground and lack of enforcement of existing rules emerge as the weakest link in the fight against air pollution. Experts, tracking the issue for years, have flagged how all sectors have policies and rules but their implementation and enforcement are not stringent and uniform, leaving the people in capital city and neighbouring areas gasping for breath. They also underlined that real action to deal with vehicular pollution (the largest contributor of pollution in Delhi), industrial emissions, waste burning and construction/demolition dust should not be pushed to back burner while red-flagging only episodic events like stubble burning whose contribution, in any case, is less than the other sources put together. “While several measures taken over the years to clean up fuels and technology across transport and industry as well as to control dust have helped to stabilise and bend the longer term particulate trends, more action is needed at scale and speed to address the remaining policy gaps for meeting the clean air targets in Delhi,” said Anumita Roychowdhury of the Centre for Science and Environment (CSE). Noting that the Graded Response Action Plan (GRAP) measures are just temporary emergency response to prevent further loading of pollution when the pollution is already tapped in the city, she said, “While this emergency action is largely confined to dust control, construction, truck movement, open burning etc, this requires very stringent enforcement, monitoring and penal action cross the city.” Asked to identify few actions which Delhi-NCR should have taken round-the-year but it didn’t, another expert Sunil Dahiya of Centre for Research on Energy and Clean Air (CREA) pointed out at inefficient progress on strengthening public transportation and non-motorised transport infrastructure, lack of enforcement of emission regulations aiming to reduce emission load from industries and coal-based power plants, and absence of emission load reduction-based approach for key polluting sectors and geographies as critical gaps which led to the current situation. He also underlined that the portrayal of false solutions to air pollution in the form of anti-smog guns and smog towers has actually led to diversion from real solutions of emission load reduction at pollution sources. Both Roychowdhury and Dahiya pitched for using an airshed approach to deal with the situation through comprehensive measures as air pollutants don’t have boundaries. “The regional or airshed based approach to pollution control with a strong compliance and implementation strategy, effective financing and monitoring are urgently needed to make a difference,” said Roychowdhury, noting that only Delhi centric measures would not suffice as pollution blows between boundaries. Hundred percent collection, segregation and recycling of all waste, remediation of legacy waste in all dump sites, elimination of dirty fuels in all non-confirming industries and households, and stronger hyper local action on all other pollution sources are some of the areas where the authorities need to act round-the-year. Source link

Delhi air pollution: Odd-even vehicle plan to be implemented for a week after Diwali

The odd-even plan will be implemented in the national capital territory from November 13 to November 20 to curb air pollution, Delhi’s Environment Minister Gopal Rai said on Monday as air quality remained in the “severe” category for the fifth consecutive day despite mitigation efforts. The rule, which allows vehicles with odd-numbered licence plates on the road on dates with odd numbers and those with even-numbered plates on others, will be enforced a day after Diwali. “After studying the situation following the implementation, a decision will be taken on future actions,” he added. Rai said that the decision was taken considering the likelihood that pollution levels will rise after the festival, during which firecrackers, even though banned, are often set on fire. Air quality plunges in the winter months in Delhi, which is often ranked the world’s most polluted capital. Stubble burning in Punjab and Haryana, along with falling temperatures, low wind speed and emissions from industries and coal-fired plants contribute to air pollution in the region. At 3 pm on Monday, Delhi’s air quality index stood at 411, according to real-time figures from the Ministry of Earth Sciences’ SAFAR, or System of Air Quality and Weather Forecasting And Research. An air quality index ranging between 401 and 500 falls under the “severe” category. A reading of above 400 can affect healthy people and seriously impact those with existing illnesses. Levels of the PM2.5 fine particles was 261 micrograms per cubic meter. Particulate matter smaller than 2.5 microns (or about ten-thousandth of an inch) are particularly dangerous to human health. Such particles are small enough to travel deep into the respiratory system, potentially impairing lung function. To be considered safe, the National Ambient Air Quality Standards require PM2.5 concentration in air to be less than 60 micrograms per cubic metre in any given 24-hour period. At a press conference on Monday, Rai said that all schools will be shut across the national capital till November 10. This is excluding students of Classes 10 and 12 preparing for board examinations. On Sunday, the Commission for Air Quality Management put the Graded Response Action Plan, a set of anti-pollution measures, into effect at its highest level in Delhi and surrounding cities to tackle the crisis. This includes a ban on entry of trucks into Delhi, with some exceptions. Further, light commercial vehicles registered outside Delhi will not be allowed to enter the city, with exceptions in place for vehicles that run on compressed natural gas, electricity or BS-VI diesel. A ban has also been imposed on construction and demolition activities related to linear projects such as roads, flyovers and pipelines. On Sunday, Delhi-based think tank Centre for Science and Environment said in its report that the early start of the national capital’s smog episodes this year as compared to 2022 may be attributed to the low rainfall in September and October. At least three consecutive days of air quality index being in the “severe” category is considered one smog episode.

Pollution in Delhi soar 68% within 24hrs: CSE Report

Delhi experienced a sudden and significant spike in pollution levels on November 2, with PM2.5 concentration levels soaring by 68% within 24 hours, crossing the ‘severe+’ category as per the Air Quality Index (AQI) concentration range. The analysis released by the Centre for Science and Environment (CSE) in response to the deadly winter pollution currently gripping Delhi-NCR. Anumita Roychowdhury, executive director of research and advocacy at CSE, stated that this winter season has begun with much higher pollution levels compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has dangerously tipped the scale, increasing public health risk. Roychowdhury added that even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This situation demands the most stringent and sustained action on vehicles, industry, energy systems, and waste management across the region. Sudden Smog Increase in Delhi The analysis, conducted by CSE’s Urban Lab, highlights the sudden and rapid build-up of smog in the early phase of winter. On November 2, PM2.5 levels in Delhi crossed the ‘severe+’ level for the first time this season, marking a sudden escalation of 68% within 24 hours. Avikal Somvanshi, head of CSE’s Urban Lab, noted that such rapid build-up is not uncommon during this part of the season and is generally associated with smoke from farm stubble fires and meteorological factors assisting the transportation of smoke to Delhi-NCR. However, he emphasized that the rapid build-up in a short time span is able to tip air quality into the severe category because baseline pollution from local sources is already very high.

Severe air quality alarm in Delhi-National Capital Region before Diwali: Government forecast

A cocktail of traffic and energy emissions, crop residue fires and weather patterns typical for this time of the year has pushed peak concentrations of tiny dust and soot particles far beyond acceptable levels across the National Capital Region (NCR). The peak concentrations of particulate matter smaller than 10 microns (or PM2.5) — small enough to penetrate deep inside human lungs — could exceed acceptable levels up to four-fold over Delhi through this week and rise even higher during Diwali, a government air quality forecast said on Monday. The air quality early warning system run by the Indian Institute of Tropical Meteorology, Pune, has predicted that peak concentrations of PM2.5 will spike up to 250 micrograms per cubic metre every evening over the next three days, dip slightly on Friday and Saturday, and rise on November 12 and 13. The permissible limit for PM2.5 in India is 60 micrograms per cubic metre over a 24-hour period. Environmental experts say the NCR’s air quality, deteriorating over the past week, is a fresh reminder of inadequate air pollution control measures. Central and state authorities over the years have taken several measures to clean up fuels and technology across the transport and industry sectors, control dust sources and discourage crop residue fires. But more action is needed to meet clean air targets, said Anumita Roychowdhury, executive director for research and advocacy at the Centre for Science and Environment (CSE), a non-government entity in New Delhi. “Only this (more action) can prevent the buildup of such smog episodes that endanger public health,” she said. Amnesty International also issued a statement on Monday calling for immediate action to address India’s “prolonged air emergency levels”. “The annual air emergency in Delhi is neither a new problem nor one that comes without warning,” Ann Harrison, Amnesty International’s climate adviser said in a statement. “The government’s repeated failure(s) to protect people from exposure to hazardous air in Delhi and surrounding areas risk violating their human rights to life and health,” she said. The CSE said the most notable trend this year has been the sudden and rapid buildup of smog in the early phase of winter. On November 2, PM2.5 levels over Delhi exceeded 300 microgram per cubic metre, rising 68 per cent within 24 hours and reaching the “severe” level for the first time in the season. Weather scientists tracking air quality said wind direction and strength play a critical role in the air quality over the NCR. “The crop stubble fires only add to large baseline levels of other sources of pollution. But the wind direction typically moves the soot like a river towards NCR,” said a scientist who asked not to be named. The Centre has said it has released over Rs 3,300 crore under a crop residue management scheme to discourage paddy straw burning. The Union environment ministry said last month that the counts of paddy straw fires across northern India from mid-September to end-October had dropped from more than 13,600 fires in 2022 to 6,300 in the same period this year.

Delhi NCR air pollution Highlights: Ban on BS-III petrol vehicles and BS-IV diesel vehicles to continue in GRAP-4

The air pollution situation across Delhi NCR does not seem to improve, despite several measures being taken by the respective government and administration. The air quality in the city was in ‘severe plus’ category on Monday morning with overall AQI at 471, as per the data shared by the System of Air Quality and Weather Forecasting And Research (SAFAR). Meanwhile, the AQI in Noida was even worse at 550. The AQI in Gurugram stood at 467. Delhi government has announced that schools up to Class 5 in the city will remain closed, and Class 6 to 10 can shift to online lectures. Meanwhile in Noida, as the city’s air quality turned ‘severe’, several schools have stopped all outdoor activities and some of them have even announced switching to online classes. In addition to this, the Commission for Air Quality Management (CAQM) has decided to invoke Stage IV of the GRAP in the entire NCR with immediate effect on Sunday. Ban on BS-III petrol vehicles and BS-IV diesel vehicles will be continued in GRAP-4: Delhi minister Delhi Environment Minister Gopal Rai on Monday said,”The ban that was imposed on BS-III petrol vehicles and BS-IV diesel vehicles will be continued in GRAP-4… Except for LNG, CNG and electric trucks of the essential commodities and essential service vehicles, other trucks are banned entry into Delhi…In GRAP-3, demolition work at Flyovers, overbridges and power transmission pipelines was given an exemption…Now they are also banned.” Delhi air pollution LIVE: NASA shares Punjab farm fires’pic BJP leader Amit Malviya took to Twitter and said, “As per NASA satmap this morning, stubble burning continues unabated in Punjab. Smog from these farm-fires are choking Delhi. Despite AAP running both Punjab and Delhi, Arvind Kejriwal couldn’t care. His negligence is killing our children and aged, people are falling ill across…” Delhi air pollution news: IIT-K says artificial rain is the solution The researchers at the Indian Institute of Technology (IIT) Kanpur have developed the technology of cloud seeding and artificial rain. They say that with the help of the artificial rains, the pollutants present in the air will settle down. In this technique, a special type of chemical is sprayed on the clouds through planes, after which it starts raining. In the past, China has also used it on some special occasions. Delhi AQI news Live: Poor air quality, smog result of low rainfall A report by the Centre for Science and Environment (CSE) has suggested that poor air quality and smog have begun early in Delhi this year when compared to last year due to low rainfall in September and October. The report further said in 2022-23 winters, a similar heavy smog instance was witnessed from January 6 to January 9. To note, three consistent days of severe AQI is considered one smog episode.

Opinion: Innovations for disaster resilience exist – now we must help them scale up

Crisis response and preparedness has come a long way – but to manage future disasters, we need to support a marketplace for tried-and-tested innovations – and to learn from experience in countries like India. Meenakshi Iyer and Aarti MohanFew calamities are as devastating as a natural disaster. The decades of repercussions and humanitarian crises inflicted by a tsunami, earthquake or flood echo a sense of helplessness globally as communities and nations rally to respond. India is no stranger to this feeling. In the first nine months of 2022, India experienced some form of extreme weather on 88% of the days, according to the Centre for Science and Environment. From floods in Uttar Pradesh and landslides in Manipur, to a cyclone in Tamil Nadu, these natural disasters are part of a larger pattern of climate change that is affecting all of us. Equally of concern are the areas across the country that are vulnerable to natural climate-related changes, which bring irrecoverable loss to livelihoods and material damage along both coastal areas and mountains. To withstand these domino effects, a public-private ecosystem needs to rally together. Not only to enable greater predictability in how we prepare for, respond to, and recover from natural disasters, but also to look at the bigger picture of how we are sustainably funding climate resilience, and mitigating rising instances of natural disasters for people and planet. India: agility and innovation The promise of 2023 was shaken by the Turkey-Syria earthquake in February; more recently we observed the catastrophe of wildfires in Hawaii, one of the deadliest US wildfires in more than a century. Manu GuptaIndia’s approach to disasters has evolved over time. In the 1990s, warnings did not reach people on time or were not accurate, and this led to a “paralysis of the system not being able to respond,” according to Dr. Manu Gupta, co-founder at SEEDs, a non-profit building resilience against disaster and climate change impacts. However, Gupta, who has over 30 years of experience in disaster management, says the system in India “has moved towards a zero-casualty approach” – in other words, there is an explicit focus on saving lives. A big shift in how India now deals with natural disasters is also through empowering communities to be first responders. Covid-19 has opened up the possibilities of how disasters can be managed. By May 2021, the number of new cases confirmed in India had peaked at just over 390,000 and demand for medical oxygen rose ten-fold. Neetha Joy, a director at ACT Grants, a non-profit venture philanthropy platform, shares how the Indian government, in a fight or flight moment, was open to all ideas at that time. This enabled agility and innovation to be fast-tracked. The Indian government, in a fight or flight moment, was open to all ideas “In a non-pandemic situation, this wouldn't have come together so quickly,” Joy says, including “getting all these unlikely stakeholders together on a table, ideating, coming up with a solution and seamlessly making it work. It was a good peek into what can happen.” Neetha JoySolutions for telemedicine, oxygen supply grids, and continuity of patient care were enabled by the government. All this was made possible by the government relaxing certain barriers to direct capital for entrepreneurs, and through concerted efforts across the healthcare ecosystem. However, Joy also cautions that, as post-pandemic society has started to move back to business as usual, so have startups and the government. Maintaining the momentum and elasticity for innovation that such disruptions in the face of disaster can offer is critical to make innovation scalable. Incentivising entrepreneurs In India there are some exciting innovations being trialled to manage natural disasters better. Technology is a popular and exciting prospect for innovation in this regard, from the potential of drones and robotics, to enabling digital public goods and infrastructure (DPG/DPI). Gupta’s team is working on developing DPGs that can be used in a natural disaster, to provide real-time information on the type of losses people experience for better responsiveness. Capturing this information would not only account for physical loss, but also for issues around “fears or sentiments… because mental health has become a major issue,” he says.

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to "severe plus" category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: "This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. "Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region." The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: "This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. "But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high." The report pointed out that the most notable trend this year is the "sudden and rapid build-up of smog" episode in this early phase of winter. "On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or 'severe plus' level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours," it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. "This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19," it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. "In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with 'good' PM2.5 AQI before the onset of winter was observed on September 9, 2023," it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE's Urban Lab listed the key factors behind Delhi's toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi's Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. "While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent -- highest this season indicating the higher influence of combustion sources," the report stated. It further said that SAFAR's estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. "It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November," it noted. The report also stated that the levels of NO2 – which comes largely from vehicles -- are also rising in the region. "This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard," it said. ITO is most polluted NO2 location in Delhi, with an average of 219 microgrammes/cubic metre. Nehru Nagar and Siri Fort are the next most polluted NO2 locations in Delhi, the report said.

Behind Toxic Delhi Air, Local Factors' Role Bigger Than Farm Fires: Experts

Delhi AQI levels have been in the 'severe' category for the past few days. PTI New Delhi: Stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's skyline, a latest report on Delhi's toxic air quality has pointed out. Anumita Roychowdhury, executive director of Centre for Science and Environment, told NDTV that their latest report has found that PM2.5 levels in Delhi-NCR rose by a "staggering and unprecedented" 68 per cent within just 24 hours on November 2. The spike in PM2.5 levels was recorded at a time when the contribution of stubble burning in Delhi's PM2.5 levels is gradually declining. Data recorded by System of Air Quality and Weather Forecasting And Research (SAFAR) and Decision Support System For Air Quality Management In Delhi has shown that the share of stubble burning in Delhi's PM2.5 concentration over the past few days has been in the 25-35 per cent range -- lower than previous years. This component is likely to rise as stubble burning reaches its peak.

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to "severe plus" category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: "This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. "Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region." The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: "This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. "But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high." The report pointed out that the most notable trend this year is the "sudden and rapid build-up of smog" episode in this early phase of winter. "On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or 'severe plus' level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours," it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. "This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19," it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. "In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with 'good' PM2.5 AQI before the onset of winter was observed on September 9, 2023," it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE's Urban Lab listed the key factors behind Delhi's toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi's Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. "While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent -- highest this season indicating the higher influence of combustion sources," the report stated. It further said that SAFAR's estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. "It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November," it noted. The report also stated that the levels of NO2 – which comes largely from vehicles -- are also rising in the region. "This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard," it said. ITO is most polluted NO2 location in Delhi, with an average of 219 microgrammes/cubic metre. Nehru Nagar and Siri Fort are the next most polluted NO2 locations in Delhi, the report said. --IANS

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to "severe plus" category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: "This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. "Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region." The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: "This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. "But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high." The report pointed out that the most notable trend this year is the "sudden and rapid build-up of smog" episode in this early phase of winter. "On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or 'severe plus' level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours," it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. "This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19," it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. "In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with 'good' PM2.5 AQI before the onset of winter was observed on September 9, 2023," it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE's Urban Lab listed the key factors behind Delhi's toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi's Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. "While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent -- highest this season indicating the higher influence of combustion sources," the report stated. It further said that SAFAR's estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. "It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November," it noted. The report also stated that the levels of NO2 – which comes largely from vehicles -- are also rising in the region. "This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard," it said. ITO is most polluted NO2 location in Delhi, with an average of 219 microgrammes/cubic metre. Nehru Nagar and Siri Fort are the next most polluted NO2 locations in Delhi, the report said.

STUBBLE BURNING NOT ONLY TO BLAME FOR ALARMING SPIKE IN AIR QUALITY IN DELHI: CSE REPORT

New Delhi, Nov 7 , Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to “severe plus” category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi’s air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital’s air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: “This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. “Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region.” The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: “This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. baseline pollution from local sources is already very high.” The report pointed out that the most notable trend this year is the “sudden and rapid build-up of smog” episode in this early phase of winter. “On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or ‘severe plus’ level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours,” it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. “This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19,” it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. “In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with ‘good’ PM2.5 AQI before the onset of winter was observed on September 9, 2023,” it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE’s Urban Lab listed the key factors behind Delhi’s toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi’s Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. “While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent — highest this season indicating the higher influence of combustion sources,” the report stated.

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to “severe plus” category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi’s air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital’s air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: “This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. “Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region.” The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: “This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. “But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high.” The report pointed out that the most notable trend this year is the “sudden and rapid build-up of smog” episode in this early phase of winter. “On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or ‘severe plus’ level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours,” it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. “This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19,” it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. “In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with ‘good’ PM2.5 AQI before the onset of winter was observed on September 9, 2023,” it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE’s Urban Lab listed the key factors behind Delhi’s toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi’s Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. “While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent — highest this season indicating the higher influence of combustion sources,” the report stated. It further said that SAFAR’s estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. “It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November,” it noted. The report also stated that the levels of NO2 – which comes largely from vehicles — are also rising in the region. “This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard,” it said. ITO is most polluted NO2 location in Delhi, with an average of 219 microgrammes/cubic metre. Nehru Nagar and Siri Fort are the next most polluted NO2 locations in Delhi, the report said.

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to “severe plus” category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi’s air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital’s air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: “This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. “Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region.” The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: “This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. “But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high.” The report pointed out that the most notable trend this year is the “sudden and rapid build-up of smog” episode in this early phase of winter. “On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or ‘severe plus’ level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours,” it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. “This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19,” it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. “In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with ‘good’ PM2.5 AQI before the onset of winter was observed on September 9, 2023,” it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE’s Urban Lab listed the key factors behind Delhi’s toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi’s Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. “While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent — highest this season indicating the higher influence of combustion sources,” the report stated. It further said that SAFAR’s estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. “It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November,” it noted. The report also stated that the levels of NO2 – which comes largely from vehicles — are also rising in the region. “This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard,” it said. ITO is most polluted NO2 location in Delhi, with an average of 219 microgrammes/cubic metre. Nehru Nagar and Siri Fort are the next most polluted NO2 locations in Delhi, the report said.

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to “severe plus” category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi’s air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital’s air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: “This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. “Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region.” The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: “This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. “But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high.” The report pointed out that the most notable trend this year is the “sudden and rapid build-up of smog” episode in this early phase of winter. “On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or ‘severe plus’ level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours,” it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. “This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19,” it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. “In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with ‘good’ PM2.5 AQI before the onset of winter was observed on September 9, 2023,” it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE’s Urban Lab listed the key factors behind Delhi’s toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi’s Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. “While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent — highest this season indicating the higher influence of combustion sources,” the report stated. It further said that SAFAR’s estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. “It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November,” it noted. The report also stated that the levels of NO2 – which comes largely from vehicles — are also rising in the region. “This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard,” it said.

Stubble burning not only to blame for alarming spike in air quality in Delhi: CSE report

Delhi’s pollution level – PM2.5 concentration – saw its first huge spike of this winter season on November 2 with a sudden and staggering 68 per cent jump within 24 hours, crossing 313 microgramme per metre cubed which was equivalent to "severe plus" category as per the Air Quality Index (AQI) concentration range, the Centre for Science and Environment (CSE) said in its latest study. It also said that stubble burning alone could not have led to this alarming spike in Delhi's air pollution levels if local factors, including vehicle emissions, had not already poisoned the national capital's air. Releasing the new analysis by CSE of the deadly winter pollution that has gripped Delhi-NCR these days, CSE Executive Director, Research and Advocacy, Anumita Roychowdhury said: "This winter season has started with a much higher pollution level compared to November last year. The combination of adverse meteorological conditions, onset of crop residue burning, and high local pollution has tilted the scale dangerously, increasing public health risk. "Even though the overall long-term pollution curve is stable and downward, it is still significantly above the national ambient air quality standards. This demands most stringent and sustained action on vehicles, industry, energy systems and waste management across the region." The analysis has been done by CSE’s Urban Lab, whose head Avikal Somvanshi said: "This kind of rapid build-up is not uncommon during this part of the season and is generally associated with smoke-fall from farm stubble fire and meteorological factors assisting transportation of the smoke to Delhi-NCR and topping the high local pollution. "But it must be kept in consideration that this rapid build-up in a short time span is able to tip air quality into severe category because baseline pollution from local sources is already very high." The report pointed out that the most notable trend this year is the "sudden and rapid build-up of smog" episode in this early phase of winter. "On November 2, PM2.5 levels in Delhi crossed 300 microgrammes/cubic metre or 'severe plus' level for the first time this season. It was a very sudden escalation as the level rose a staggering 68 per cent within 24 hours," it said. The analysis pointed out that during the previous five years, overall trends show that PM2.5 levels start to rise steadily from the beginning of October. "This year, the levels started to rise from the middle of September. Illustratively, this increase was at a slower rate and by the end of October, the levels were 20-30 per cent lower than the average levels for the corresponding Octobers of the previous five winters – since 2018-19," it said. It further pointed out that early beginning of bad air quality days this year due to lower rainfall during September and October. "In contrast to the previous winter of 2022-23, the smog episode has started earlier this year. The last day with 'good' PM2.5 AQI before the onset of winter was observed on September 9, 2023," it said. It remains to be seen how many more smog episodes with varying durations may occur this winter. As is the global practice, at least three continuous days of severe AQI is considered as one smog episode. In previous winters, such episodes have been recorded lasting six-10 days the winters between 2018 and 2021 had, on an average, experienced three smog episodes each. During the winter of 2022-23, only one smog episode was recorded from January 6-9. Also, Diwali and late December of 2022-23 did not witness a smog episode (like in the earlier winters). The analysis by CSE's Urban Lab listed the key factors behind Delhi's toxic air. The report noted that this spike in pollution levels is not uncommon during this time of the year and is generally associated with stubble burning in north Indian states before farmers start work on the winter crop. Meterological factors helping the movement of smoke to Delhi-NCR is also behind the jump in Delhi's Air Qualty Index, it said. The report also stated that share of PM2.5 in PM10 is an important indicator of the impact of combustion sources. "While coarser PM10 comes largely from dust sources, the tinier PM2.5 come more from vehicles, industry and open burning. This year the percentage share of PM2.5 in PM10 has crossed 50 per cent, which indicates higher impact of combustion sources. On November 2, the ratio for PM2.5 stood at 60 per cent -- highest this season indicating the higher influence of combustion sources," the report stated. It further said that SAFAR's estimate has shown that the percentage contribution of farm stubble fire to Delhi’s PM2.5 concentration had crossed 25 per cent on November 2. "It was in the 10-20 per cent range in the week leading to November 2. This is expected to rise in the coming days. The fire instances in Punjab and Haryana are yet to peak. In previous years, on the worst days, its contribution had topped 40 per cent, as generally noted during the middle of November," it noted. The report also stated that the levels of NO2 – which comes largely from vehicles -- are also rising in the region. "This indicates high impact of vehicular pollution. City-wide average NO2 is up by 60 per cent compared to the first week of October last year. Certain high traffic locations have been reporting levels as high as three-four times the 24-hour standard," it said. ITO is most polluted NO2 location in Delhi, with an average of 219 microgrammes/cubic metre. Nehru Nagar and Siri Fort are the next most polluted NO2 locations in Delhi, the report said.