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दिल्ली की साफ हवा ने तोड़ा 8 साल का रेकॉर्ड, अक्टूबर-नवंबर महीने में औसत AQI रहा 142

नई दिल्ली: सर्दियों का पहला फेज 8 सालों में सबसे साफ रहा है। सीएसई की नई रिपोर्ट में यह दावा किया गया है। रिपोर्ट के अनुसार इन दो महीनों में राजधानी का औसत एक्यूआई 142 एमजीसीएम रहा। 2018 की तुलना में यह 18 प्रतिशत तक कम रहा, जबकि 2016 की तुलना में यह 38 प्रतिशत तक कम है। 2016 के अक्टूबर-नवंबर अब तक के सबसे प्रदूषित दो महीने रहे हैं। दिल्ली-एनसीआर में राजधानी सबसे प्रदूषित गाजियाबाद में इन दो महीनों के प्रदूषण स्तर में 2020 की तुलना में 36 प्रतिशत की कमी आई है। वहीं, ग्रेटर नोएडा में 28 प्रतिशत, फरीदाबाद में 22 प्रतिशत की कमी आई है। इस दौरान 19 प्रतिशत, गुरुग्राम में 15 प्रतिशत और नोएडा में 40 प्रतिशत की कमी आई। दिल्ली-एनसीआर में सबसे प्रदूषित क्षेत्र राजधानी रही है। दूसरे नंबर पर गुरुग्राम और तीसरे पर गाजियाबाद रहा।

October-November period least polluted in Delhi in eight years: CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. “Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter pollution curve,” said Anumita Roychowdhury, executive director, research and advocacy, CSE. But there may be more spikes later as has usually been observe

Delhi Pollution: Smoke Intrusion From Farm Fires In Oct-Nov Lowest In Four Years: Centre for Science and Environment

Not only have the number of farm fires in Punjab and Haryana this season been the lowest since 2016, the national capital also witnessed the least smoke intrusion from stubble burning during October-November in four years, according to a Centre for Science and Environment analysis. Analysis of data from SAFAR, the Union Ministry of Earth Sciences' air quality forecasting agency, shows that smoke from farm fires contributed to PM2.5 pollution in Delhi on 53 days this year, starting October 12. The figure is lower than the previous three years when smoke intrusion was reported on 56-57 days but higher than the 2018 reading of 48 days. https://www.millenniumpost.in/big-stories/delhi-pollution-smoke-intrusion-from-farm-fires-in-oct-nov-lowest-in-four-years-centre-for-science-and-environment-502079

Delhi pollution: Smoke intrusion from farm fires in Oct-Nov lowest in four years, says CSE

Not only have the number of farm fires in Punjab and Haryana this season been the lowest since 2016, the national capital also witnessed the least smoke intrusion from stubble burning during October-November in four years, according to a Centre for Science and Environment analysis. Analysis of data from SAFAR, the Union Ministry of Earth Sciences' air quality forecasting agency, shows that smoke from farm fires contributed to PM2.5 pollution in Delhi on 53 days this year, starting October 12. The figure is lower than the previous three years when smoke intrusion was reported on 56-57 days but higher than the 2018 reading of 48 days. The highest contribution this year was 34 per cent on November 3. Last year, the share of farm fires in Delhi's PM 2.5 pollution peaked to 48 per cent on November 7. The Centre for Science and Environment (CSE) said stubble burning-related smokefall over Delhi depended on two major factors -- the number and intensity of farm fires and meteorological conditions conducive for the transportation of the smoke to the national capital. This October-November, not only have the quantity and intensity of farm fires been comparatively lower but also the meteorological conditions less conducive for transport of the smoke, the green think tank said. The CSE estimated that smoke from farm fires accounted for 4.1 tonnes of PM2.5 during October-November in Delhi. This is 37 per cent lower than 6.4 tonnes of PM2.5 from stubble burning last year and almost half the 2020 figure (8 tonnes). The volume this year is also significantly lower than the 2019 figure (6.4 tonnes) -- an indicator of the meteorological help Delhi got as there were fewer farm fires in 2019. According to the Indian Agriculture Research Institute, Punjab, which accounts for the maximum cases of stubble burning every year, reported just 49,922 farm fires this season (September 15 to November 30) against 71,304 last year and 83,002 in 2020. The agrarian state logged 50,738 incidents of stubble burning in 2019; 59,684 in 2018; 67,079 in 2017 and 1,02,379 in 2016. Haryana logged 3,661 farm fires this season against 6,987 in 2021 and 4,202 in 2020. The neighbouring state saw 6,364 incidents of stubble burning in 2019; 9,225 in 2018; 13,085 in 2017 and 15,686 in 2016.

Delhi pollution: Smoke intrusion from farm fires in Oct-Nov lowest in four years, says CSE

The figure is lower than the previous three years when smoke intrusion was reported on 56-57 days but higher than the 2018 reading of 48 days. The highest contribution this year was 34 per cent on November 3. Last year, the share of farm fires in Delhi's PM 2.5 pollution peaked to 48 per cent on November 7. Factors at play The Centre for Science and Environment (CSE) said stubble burning-related smokefall over Delhi depended on two major factors — the number and intensity of farm fires and meteorological conditions conducive for the transportation of the smoke to the national capital.

Delhi Pollution: Smoke Intrusion From Farm Fires In Oct-Nov Lowest In Four Years, Says CSE

Not only have the number of farm fires in Punjab and Haryana this season been the lowest since 2016, the national capital also witnessed the least smoke intrusion from stubble burning during October-November in four years, according to a Centre for Science and Environment analysis. Analysis of data from SAFAR, the Union Ministry of Earth Sciences' air quality forecasting agency, shows that smoke from farm fires contributed to PM2.5 pollution in Delhi on 53 days this year, starting October 12. The figure is lower than the previous three years when smoke intrusion was reported on 56-57 days but higher than the 2018 reading of 48 days. The highest contribution this year was 34 per cent on November 3. Last year, the share of farm fires in Delhi's PM 2.5 pollution peaked to 48 per cent on November 7. The Centre for Science and Environment (CSE) said stubble burning-related smokefall over Delhi depended on two major factors -- the number and intensity of farm fires and meteorological conditions conducive for the transportation of the smoke to the national capital. This October-November, not only have the quantity and intensity of farm fires been comparatively lower but also the meteorological conditions less conducive for transport of the smoke, the green think tank said. The CSE estimated that smoke from farm fires accounted for 4.1 tonnes of PM2.5 during October-November in Delhi. This is 37 per cent lower than 6.4 tonnes of PM2.5 from stubble burning last year and almost half the 2020 figure (8 tonnes). The volume this year is also significantly lower than the 2019 figure (6.4 tonnes) -- an indicator of the meteorological help Delhi got as there were fewer farm fires in 2019. According to the Indian Agriculture Research Institute, Punjab, which accounts for the maximum cases of stubble burning every year, reported just 49,922 farm fires this season (September 15 to November 30) against 71,304 last year and 83,002 in 2020. The agrarian state logged 50,738 incidents of stubble burning in 2019; 59,684 in 2018; 67,079 in 2017 and 1,02,379 in 2016. Haryana logged 3,661 farm fires this season against 6,987 in 2021 and 4,202 in 2020. The neighbouring state saw 6,364 incidents of stubble burning in 2019; 9,225 in 2018; 13,085 in 2017 and 15,686 in 2016.

Delhi pollution: Smoke intrusion from farm fires in Oct-Nov lowest in four years, says CSE

Not only have the number of farm fires in Punjab and Haryana this season been the lowest since 2016, the national capital also witnessed the least smoke intrusion from stubble burning during October-November in four years, according to a Centre for Science and Environment analysis.Analysis of data from SAFAR, the Union Ministry of Earth Sciences" air quality forecasting agency, shows that smoke from farm fires contributed to PM2.5 pollution in Delhi on 53 days this year, starting October 12.The figure is lower than the previous three years when smoke intrusion was reported on 56-57 days but higher than the 2018 reading of 48 days.The highest contribution this year was 34 per cent on November 3. Last year, the share of farm fires in Delhi"s PM 2.5 pollution peaked to 48 per cent on November 7.The Centre for Science and Environment (CSE) said stubble burning-related smokefall over Delhi depended on two major factors -- the number and intensity of farm fires and meteorological conditions conducive for the transportation of the smoke to the national capital.This October-November, not only have the quantity and intensity of farm fires been comparatively lower but also the meteorological conditions less conducive for transport of the smoke, the green think tank said.The CSE estimated that smoke from farm fires accounted for 4.1 tonnes of PM2.5 during October-November in Delhi. This is 37 per cent lower than 6.4 tonnes of PM2.5 from stubble burning last year and almost half the 2020 figure (8 tonnes).The volume this year is also significantly lower than the 2019 figure (6.4 tonnes) -- an indicator of the meteorological help Delhi got as there were fewer farm fires in 2019.According to the Indian Agriculture Research Institute, Punjab, which accounts for the maximum cases of stubble burning every year, reported just 49,922 farm fires this season (September 15 to November 30) against 71,304 last year and 83,002 in 2020.The agrarian state logged 50,738 incidents of stubble burning in 2019; 59,684 in 2018; 67,079 in 2017 and 1,02,379 in 2016.Haryana logged 3,661 farm fires this season against 6,987 in 2021 and 4,202 in 2020. The neighbouring state saw 6,364 incidents of stubble burning in 2019; 9,225 in 2018; 13,085 in 2017 and 15,686 in 2016. PTI GVS SZM

Oct-Nov period least polluted in Delhi in eight years: CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. ”Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter pollution curve,” said Anumita Roychowdhury, executive director, research and advocacy, CSE. But there may be more spikes later as has usually been observed in previous years. Stronger pre-emptive measures and deeper round-the-year action on local sources is needed to bring down the winter pollution to satisfactory levels, she said. The CSE analysis is based on real-time data available from functional air quality monitoring stations in Delhi-NCR. There are 81 continuous ambient air quality monitoring stations (CAAQMS) spread across the region. The analysis showed that average PM2.5 levels across 37 functional CAAQMS stations in Delhi stood at 142 micrograms per cubic metre (µg/m3) for the months of October and November. This is the lowest level recorded since the city installed these stations in 2018. ”If data for the 10 oldest stations (working since 2014-15) is referred to, October-November of this year remains the least polluted in comparison,” the CSE said. The PM2.5 level this October-November has been 38 per cent lower as compared to October-November of 2016, which was the worst in the last eight years. Ghaziabad’s October-November average PM2.5 this year is 36 per cent lower than the same period in 2020. Similarly, Greater Noida and Faridabad registered improvements of 28 per cent and 22 per cent, respectively. This is higher than Delhi’s city-wide improvement of 19 per cent in the same time frame. Gurugram showed the least improvement with a mere 15 per cent change. Noida’s October-November average PM2.5 this year appears to be 40 per cent lower than the same period in 2020. However, it may be noted that one of Noida’s CAAQM stations is reporting uncharacteristically low values this season. This needs to be examined, the CSE said. Delhi was the most polluted major city in NCR with an October-November average of 142 µg/m3, followed by Gurugram (134 µg/m3) and Ghaziabad (131 µg/m3). The CSE analysis also showed that there has been no severe smog episode so far during this season. This makes the October-November period the first in the last five years to be smog-free. It is considered a severe smog episode when the air quality index remains in the ‘severe’ category for at least three consecutive days. There is usually one smog episode during October-November lasting six-ten days. During the winter of 2021, there were three smog episodes – two in November and one in December. November 2021 had recorded the longest smog episode of 10 continuous days (4-13 November). Such events have not occurred this winter. Farm fires this year were about half of the previous year. The total count of farm fires reported this year from Punjab, Haryana and Delhi in the months of October and November stood at 54,391, according to NASA’s VIIRS satellite and 11,824 according to NASA’s MODIS satellite. These are respectively 37 per cent and 42 per cent lower than the figures for October-November of 2021. Analysis of SAFAR data shows that this year, smoke from the farm fires contributed to PM2.5 levels in Delhi on 53 days, starting October 12 and ending on December 3. This is less than the last three years, when smoke intrusion was reported on 56 days but higher than the 2018 figure of 48 days. The highest contribution this year was 34 per cent, reported on November 3. The smoke from farm fires that covers Delhi is dependent on two major factors: number and intensity of the fires, and meteorological conditions conducive for transportation of the smoke to Delhi. This October-November, not only the number and intensity of farm stubble fires have been comparatively lower but also the meteorological conditions have been less conducive for the transport of smoke. As a result, considerably lesser smoke invaded Delhi. The CSE estimated that smoke contributed about 4.1 tonnes of PM2.5 during October-November in Delhi. This is 37 per cent lesser than the 6.4 tonnes that came last year, and also almost half of the 2020 figure. High rainfall and local wind speed helped disperse local pollution. Delhi received 115 mm of rainfall this October-November, the highest in the last five years. This helped clean up the city air, especially in October. Average wind speed for November stood at 12.4 km/hour which helped in dispersing local pollution. Average wind speed for the month in 2021 was 11 km/hour and 11.5 km/hour in 2020.

DL-POLLUTION-CSE - Oct-Nov period least polluted in Delhi in eight years: CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. "Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter ...

Delhi pollution: Smoke intrusion from farm fires in Oct-Nov lowest in four years, says CSE

Not only have the number of farm fires in Punjab and Haryana this season been the lowest since 2016, the national capital also witnessed the least smoke intrusion from stubble burning during October-November in four years, according to a Centre for Science and Environment analysis. Analysis of data from SAFAR, the Union Ministry of Earth Sciences' air quality forecasting agency, shows that smoke from farm fires contributed to PM2.5 pollution in Delhi on 53 days this year, starting October 12. The figure is lower than the previous three years when smoke intrusion was reported on 56-57 days but higher than the 2018 reading of 48 days. The highest contribution this year was 34 per cent on November 3. Last year, the share of farm fires in Delhi's PM 2.5 pollution peaked to 48 per cent on November 7. The Centre for Science and Environment (CSE) said stubble burning-related smokefall over Delhi depended on two major factors — the number and intensity of farm fires and meteorological conditions conducive for the transportation of the smoke to the national capital.

8 साल में पहली बार, अक्टूबर-नवंबर में दिल्ली सबसे कम प्रदूषित, नहीं दिखा स्मॉग

इस साल अक्टूबर-नवंबर में दिल्ली में प्रदूषण का स्तर पिछले आठ वर्षों से सबसे कम रहा है. ये हम नहीं, थिंक टैंक सेंटर फॉर साइंस एंड एनवायरनमेंट (सीएसई) की एक स्टडी कह रही है. सीएसई के अनुसार, इस बार सर्दियों के मौसम में लंबे समय तक स्मॉग नहीं दिखाई दिया. ऐसा पिछले पिछले पांच वर्षों में पहली बार हुआ है. आमतौर पर ऐसा देखा गया है कि अक्टूबर और नवंबर में 6 से 10 दिनों तक स्मॉग छाया रहता है. सीएसई की कार्यकारी निदेशक अनुमिता चौधरी ने कहा कि इस साल पराली जलाए जाने की घटनाएं कम हुई हैं. साथ ही दिवाली के दौरान भी प्रदूषण कम हुआ. यही सारी वजहें हैं, जिससे प्रदूषण का स्तर पिछले साल के मुताबिक कम हुआ है. स्टडी के अनुसार, शहर के 10 सबसे पुराने वायु गुणवत्ता निगरानी स्टेशनों के डेटा से यह भी पता चला है कि पिछले आठ वर्षों में पीएम 2.5 का स्तर कम था. प्रदूषण के स्तर में दिखी गिरावट इन 10 स्टेशनों का औसत पीएम 2.5 का स्तर 135 µg/m3 था. 2015 में इन महीनों में पीएम 2.5 का स्तर 181 µg/m3 था. 2016 और 2017 में औसत 200 µg/m3 से अधिक था. वहीं, 2021 में यह आंकड़ा 153 µg/m3 था. यह डेटा आनंद विहार, आईजीआई हवाई अड्डा, मंदिर मार्ग, पंजाबी बाग, आरके पुरम और शादीपुर में स्थित वायु निगरानी स्टेशनों के हैं. न्यूनतम तापमान 11 डिग्री सेल्सियस रहने की संभावना देश की राष्ट्रीय राजधानी दिल्ली में ठंड बरकरार है. मौसम विभाग के अनुसार, दिल्ली का आज यानि मंगलवार को न्यूनतम तापमान 11 डिग्री सेल्सियस और अधिकतम तापमान 26 डिग्री सेल्सियस रहने का अनुमान है. हालांकि, मौसम विभाग के अधिकारियों के मुताबिक, रात में तापमान और गिर सकता है. जिससे ठंड और बढ़ सकती है. दिल्ली में सोमवार को अधिकतम तापमान 27.1 डिग्री सेल्सियस दर्ज किया गया, जो इस मौसम के औसत तापमान से चार डिग्री अधिक है. दिल्ली में 24 घंटे की औसत वायु गुणवत्ता ‘खराब’ श्रेणी में दर्ज की गई. समीर ऐप के मुताबिक, वायु गुणवत्ता सूचकांक (एक्यूआई) सुबह नौ बजकर 10 मिनट पर 238 से बेहतर होकर शाम चार बजे 218 हो गया.

October-November period least polluted in Delhi in eight years: CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. “Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter pollution curve,” said Anumita Roychowdhury, executive director, research and advocacy, CSE.

Oct-Nov period least polluted in Delhi in eight years CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. "Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter pollution curve," said Anumita Roychowdhury, executive director, research and advocacy, CSE. But there may be more spikes later as has usually been observed in previous years. Stronger pre-emptive measures and deeper round-the-year action on local sources is needed to bring down the winter pollution to satisfactory levels, she said. The CSE analysis is based on real-time data available from functional air quality monitoring stations in Delhi-NCR. There are 81 continuous ambient air quality monitoring stations (CAAQMS) spread across the region. The analysis showed that average PM2.5 levels across 37 functional CAAQMS stations in Delhi stood at 142 micrograms per cubic metre (µg/m3) for the months of October and November. This is the lowest level recorded since the city installed these stations in 2018. "If data for the 10 oldest stations (working since 2014-15) is referred to, October-November of this year remains the least polluted in comparison," the CSE said. The PM2.5 level this October-November has been 38 per cent lower as compared to October-November of 2016, which was the worst in the last eight years. Ghaziabad's October-November average PM2.5 this year is 36 per cent lower than the same period in 2020. Similarly, Greater Noida and Faridabad registered improvements of 28 per cent and 22 per cent, respectively. This is higher than Delhi's city-wide improvement of 19 per cent in the same time frame. Gurugram showed the least improvement with a mere 15 per cent change. Noida's October-November average PM2.5 this year appears to be 40 per cent lower than the same period in 2020. However, it may be noted that one of Noida's CAAQM stations is reporting uncharacteristically low values this season. This needs to be examined, the CSE said. Delhi was the most polluted major city in NCR with an October-November average of 142 µg/m3, followed by Gurugram (134 µg/m3) and Ghaziabad (131 µg/m3). The CSE analysis also showed that there has been no severe smog episode so far during this season. This makes the October-November period the first in the last five years to be smog-free. It is considered a severe smog episode when the air quality index remains in the 'severe' category for at least three consecutive days. There is usually one smog episode during October-November lasting six-ten days. During the winter of 2021, there were three smog episodes – two in November and one in December. November 2021 had recorded the longest smog episode of 10 continuous days (4-13 November). Such events have not occurred this winter. Farm fires this year were about half of the previous year. The total count of farm fires reported this year from Punjab, Haryana and Delhi in the months of October and November stood at 54,391, according to NASA's VIIRS satellite and 11,824 according to NASA's MODIS satellite. These are respectively 37 per cent and 42 per cent lower than the figures for October-November of 2021. Analysis of SAFAR data shows that this year, smoke from the farm fires contributed to PM2.5 levels in Delhi on 53 days, starting October 12 and ending on December 3. This is less than the last three years, when smoke intrusion was reported on 56 days but higher than the 2018 figure of 48 days. The highest contribution this year was 34 per cent, reported on November 3. The smoke from farm fires that covers Delhi is dependent on two major factors: number and intensity of the fires, and meteorological conditions conducive for transportation of the smoke to Delhi. This October-November, not only the number and intensity of farm stubble fires have been comparatively lower but also the meteorological conditions have been less conducive for the transport of smoke. As a result, considerably lesser smoke invaded Delhi. The CSE estimated that smoke contributed about 4.1 tonnes of PM2.5 during October-November in Delhi. This is 37 per cent lesser than the 6.4 tonnes that came last year, and also almost half of the 2020 figure. High rainfall and local wind speed helped disperse local pollution. Delhi received 115 mm of rainfall this October-November, the highest in the last five years. This helped clean up the city air, especially in October. Average wind speed for November stood at 12.4 km/hour which helped in dispersing local pollution. Average wind speed for the month in 2021 was 11 km/hour and 11.5 km/hour in 2020. PTI GVS DIV DIV

October-November period least polluted in Delhi in eight years: CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. "Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter pollution curve," said Anumita Roychowdhury, executive director, research and advocacy, CSE. https://www.news9live.com/state/delhi-ncr/october-november-period-least-polluted-in-delhi-in-eight-years-cse-213668

Oct-Nov period least polluted in Delhi in eight years: CSE

The period from October to November was the least polluted in the last eight years in Delhi and there has been no severe smog episode during the winter season so far, according to green think tank Centre for Science and Environment. "Diwali in a warmer October, lower incidents of crop fires, pre-emptive action based on pollution forecasting, and favourable meteorological conditions including extended rainfall in October, have all contributed towards bending of the early winter pollution curve," said Anumita Roychowdhury, executive director, research and advocacy, CSE. But there may be more spikes later as has usually been observed in previous years. Stronger pre-emptive measures and deeper round-the-year action on local sources is needed to bring down the winter pollution to satisfactory levels, she said. The CSE analysis is based on real-time data available from functional air quality monitoring stations in Delhi-NCR. There are 81 continuous ambient air quality monitoring stations (CAAQMS) spread across the region. The analysis showed that average PM2.5 levels across 37 functional CAAQMS stations in Delhi stood at 142 micrograms per cubic metre (µg/m3) for the months of October and November. This is the lowest level recorded since the city installed these stations in 2018. "If data for the 10 oldest stations (working since 2014-15) is referred to, October-November of this year remains the least polluted in comparison," the CSE said. The PM2.5 level this October-November has been 38 per cent lower as compared to October-November of 2016, which was the worst in the last eight years. Ghaziabad's October-November average PM2.5 this year is 36 per cent lower than the same period in 2020. Similarly, Greater Noida and Faridabad registered improvements of 28 per cent and 22 per cent, respectively. This is higher than Delhi's city-wide improvement of 19 per cent in the same time frame. Gurugram showed the least improvement with a mere 15 per cent change. Noida's October-November average PM2.5 this year appears to be 40 per cent lower than the same period in 2020. However, it may be noted that one of Noida's CAAQM stations is reporting uncharacteristically low values this season. This needs to be examined, the CSE said. Delhi was the most polluted major city in NCR with an October-November average of 142 µg/m3, followed by Gurugram (134 µg/m3) and Ghaziabad (131 µg/m3). The CSE analysis also showed that there has been no severe smog episode so far during this season. This makes the October-November period the first in the last five years to be smog-free. It is considered a severe smog episode when the air quality index remains in the 'severe' category for at least three consecutive days. There is usually one smog episode during October-November lasting six-ten days. During the winter of 2021, there were three smog episodes – two in November and one in December. November 2021 had recorded the longest smog episode of 10 continuous days (4-13 November). Such events have not occurred this winter. Farm fires this year were about half of the previous year. The total count of farm fires reported this year from Punjab, Haryana and Delhi in the months of October and November stood at 54,391, according to NASA's VIIRS satellite and 11,824 according to NASA's MODIS satellite. These are respectively 37 per cent and 42 per cent lower than the figures for October-November of 2021. Analysis of SAFAR data shows that this year, smoke from the farm fires contributed to PM2.5 levels in Delhi on 53 days, starting October 12 and ending on December 3. This is less than the last three years, when smoke intrusion was reported on 56 days but higher than the 2018 figure of 48 days. The highest contribution this year was 34 per cent, reported on November 3. The smoke from farm fires that covers Delhi is dependent on two major factors: number and intensity of the fires, and meteorological conditions conducive for transportation of the smoke to Delhi. This October-November, not only the number and intensity of farm stubble fires have been comparatively lower but also the meteorological conditions have been less conducive for the transport of smoke. As a result, considerably lesser smoke invaded Delhi. The CSE estimated that smoke contributed about 4.1 tonnes of PM2.5 during October-November in Delhi. This is 37 per cent lesser than the 6.4 tonnes that came last year, and also almost half of the 2020 figure. High rainfall and local wind speed helped disperse local pollution. Delhi received 115 mm of rainfall this October-November, the highest in the last five years. This helped clean up the city air, especially in October. Average wind speed for November stood at 12.4 km/hour which helped in dispersing local pollution. Average wind speed for the month in 2021 was 11 km/hour and 11.5 km/hour in 2020. PTI GVS DIV DIV