Air pollution in Delhi

A dense toxic smog in New Delhi blocks out the sun. Photo November 8, 2017.[1]
MISR measurement, Nov. 5, 2016: The optical depth of the thick haze was too much for calculation, "because the haze is so thick that the algorithm has classified the area as cloud". (less than 37 percent of sunlight, air quality index=751).

The air quality in Delhi, the capital territory of India, according to a WHO survey of 1,650 world cities, and a survey of 7,000 world cities by the US-based Health Effects Institute in August 2022,[2] is the worst of any major city in the world. It also affects the districts around Delhi.[3][4] Air pollution in India is estimated to kill about 2 million people every year; it is the fifth largest killer in India. India has the world's highest death rate from chronic respiratory diseases and asthma, according to the WHO. In Delhi, poor quality air irreversibly damages the lungs of 2.2 million or 50 percent of all children.

On 25 November 2019, the Supreme Court of India made statements on the pollution in Delhi saying "Delhi has become worse than narak (hell)".[5] Supreme Court Justice Arun Mishra said that it is better to get explosives and kill everyone.[6]

During the COVID-19 pandemic lockdown in India, the water quality of the Yamuna and Ganges river basins improved as industries were closed due to the lockdown.[7][8][9][10] The air quality also significantly improved during the lockdown.[11]

India's Ministry of Earth Sciences published a research paper in October 2018 attributing almost 41% to vehicular emissions, 21.5% to dust and 18% to industries.[12] The director of Centre for Science and Environment alleged that the Society of Indian Automobile Manufacturers is lobbying "against the report" because it is "inconvenient" to the automobile industry...[13]

Air quality index of Delhi is generally in the Good (0–50), Satisfactory (51–100), and Moderate (101–200) levels between March and September, and then it drastically deteriorates to Poor (201–300), Severe (301–400), or Hazardous (401–500+) levels during October to February due to various factors including burning of effigies during Vijayadashami, bursting of firecrackers during Diwali, thermal power plants in NCR[14], stubble burning,[15][16] road dust, vehicle pollution and cold weather.[17][18][19] In November 2016, in an event known as the Great Smog of Delhi, the air pollution spiked far beyond acceptable levels. Levels of PM2.5 and PM 10 particulate matter hit 999 micrograms per cubic meter, while the 24-hour peak limits for those pollutants are 15 and 60 micrograms per cubic metre respectively.[20] According to Bloomberg, 16.7 lakh (1,670,000) people died due to polluted air in India in the year 2019. Further, according to data released by environment ministry in 2022, the Air Quality Index of Delhi National Capital Region is over 200 for at least half the year.[21]

Delhi's pollution problem is also caused by the factor of animal agriculture, as smog and other harmful particles are produced by farmers burning their crops in other states since the 1980s. About 80% of agriculturally used land is used for animal agriculture, so animal agriculture can also be attributed as a factor in Delhi's air pollution problem.[22][failed verification] Initiatives such as a 1,600km long and 5km wide The Great Green Wall of Aravalli green ecological corridor along Aravalli Range from Gujarat to Delhi which will also connect to the Sivalik Hills range is being considered with planting of 1.35 billion (135 crores) new native trees over 10 years to combat the pollution.[23] In December 2019, IIT Bombay, in partnership with the McKelvey School of Engineering of Washington University in St. Louis, launched the Aerosol and Air Quality Research Facility to study air pollution in India.[24]

On 15 November 2021, Delhi's air quality saw marginal improvement as it reached the lower end of the "severe" category with AQI at 318, according to the System of Air Quality and Weather Forecasting And Research. Delhi government announced to shut all the schools along with government offices[25] for a week due to the severe air pollution. The government told the Supreme court that they are confident and prepared for a complete lockdown.[26] The Supreme Court asked the centre and states of the NCR region to consider remote work policies for the employees. When the air quality of Delhi on 18 November 2021 slipped to the "severe" category with the AQI at 362, the Supreme Court of India reprimanded the central and state governments asking them to take strict measures to reduce pollution in Delhi and NCR regions.[27]

On 19 November 2021, NASA released a report on the issue of pollution in Delhi.[28]

On November 18, 2024, Delhi recorded its worst air quality of the season, with a 24-hour Air Quality Index (AQI) reading of 491, classified as "severe plus." This level, as reported by India's pollution control authority, indicates hazardous conditions with significant health impacts, particularly for vulnerable populations. The reading marks the highest AQI level for Delhi in 2024.[29]

  1. ^ Kumar, Hari; Schultz, Kai (7 November 2017). "Delhi, Blanketed in Toxic Haze, "Has Become a Gas Chamber"". The New York Times. Archived from the original on 8 November 2017. Retrieved 7 November 2017.
  2. ^ Koshy, Jacob (17 August 2022). "Delhi's PM2.5 levels worst in the world". The Hindu. Retrieved 18 August 2022.
  3. ^ "Ambient (outdoor) air pollution in cities database 2014". who.int. WHO. 2014. Archived from the original on 28 March 2014. Retrieved 31 May 2015.
  4. ^ Harris, Gardiner (14 February 2015). "Delhi Wakes Up to an Air Pollution Problem It Cannot Ignore". The New York Times. Retrieved 30 May 2015.
  5. ^ "'Delhi worse than hell': Supreme Court rebukes Centre, states on air pollution". Hindustan Times. 25 November 2019. Retrieved 26 November 2019.
  6. ^ ""Better To Get Explosives, Kill Everyone": Supreme Court On Delhi Pollution". NDTV.com. Retrieved 26 November 2019.
  7. ^ "Lockdown makes Ganga water significantly cleaner". LiveMint. 4 April 2020. Retrieved 22 April 2020.
  8. ^ Naqvi, Haider; Kumar, Sudhir (4 April 2020). "Lockdown does what decades of schemes couldn't: Clean Ganga". HT Digital Streams Ltd. Retrieved 22 April 2020.
  9. ^ "India's coronavirus lockdown reveals fresh air, cleaner rivers". Living Media India Ltd. 22 April 2020. Retrieved 22 April 2020.
  10. ^ Babu, Nikhil (14 April 2020). "Yamuna cleaner due to lockdown". The Hindu. Retrieved 22 April 2020.
  11. ^ "The silver lining: air pollution dips amid the lockdown". Retrieved 2 May 2020.
  12. ^ "Usual suspects: Vehicles, industrial emissions behind foul play". Times of India. Retrieved 18 December 2018.
  13. ^ "UA vicious nexus". Down to Earth. Retrieved 18 December 2018.
  14. ^ "Delhi Pollution: This is the reason behind the maximum pollution in Delhi-NCR, not due to stubble burning, shocking revelation in the study". NavbharatTimes.com. 17 November 2024. Thermal power plants in NCR cause 16 times more air pollution than stubble burning
  15. ^ "Out of here in November: In Delhi-NCR, smog break is becoming the new annual vacation". The Times of India. 5 November 2023.
  16. ^ "Delhi AQI: CP Smog tower down due to DPCC, says minister Gopal Rai; official says running cost high". The Times of India. 5 November 2023.
  17. ^ Vishnoi, Anubhuti (10 December 2015). "IIT-Kanpur study says trucks and road dust are bigger pollutants than cars in Delhi". The Economic Times.
  18. ^ "Delhi breathed easier from January to April". The Times of India. 6 June 2017.
  19. ^ "Air pollution: Delhi enjoys cleanest February in three years". 27 February 2018.
  20. ^ "Diwali effect: Pollution worsens, particulate matter soars in Delhi". Indian Express. 1 November 2016.
  21. ^ Rampal, Nikhil (22 July 2022). "You thought only winter meant bad air in Delhi? Govt data tells a different, worrying story". The Print. Retrieved 21 August 2022.
  22. ^ farming pollution
  23. ^ Want govt to build 1600 km green wall along Aravalli, Indian Express, 24 December 2019.
  24. ^ "McKelvey Engineering, IIT Bombay partner to study air pollution". The Source. 4 December 2019. Retrieved 14 February 2020.
  25. ^ Bhardwaj, Amit (13 November 2021). "Delhi shuts schools, govt offices for a week due to air pollution, CM Kejriwal says no lockdown for now". India Today. Retrieved 15 November 2021.
  26. ^ "Consider work from home, call emergency meet with states in NCR: What SC said on Delhi pollution". India Today. 15 November 2021. Retrieved 15 November 2021.
  27. ^ "Delhi NCR Pollution: जानें कहां क्या बंद हुआ, किन चीजों पर लगीं पाबंदियां, 20 बड़े Updates". Aaj Tak (in Hindi). 18 November 2021.
  28. ^ "हर साल दिल्ली क्यों बन जाती है 'स्मोग की राजधानी'? NASA ने जारी की रिपोर्ट". Aaj Tak (in Hindi). 19 November 2021. Retrieved 19 November 2021.
  29. ^ "India's capital chokes as air pollution levels hit 50 times the safe limit". AP News. 18 November 2024. Retrieved 18 November 2024.