Air pollution in Delhi-NCR


Context: Delhi pollution: From late October onwards, meteorological factors and ‘stubble’ burning to add to the already high pollution base in the Indo-Gangetic basin, particularly the pollution due to the Particulate Matter (PM), Haze and Smoke.

Particulate matter (PM) is made of solid particles and liquid droplets in the air. Any type of burning or dust-generating activity is a source of PM E.g., Emissions (from vehicles and industrial plant smokestacks)

Particulate matter—PM2.5 (diameter of 2.5 micrometres or less) and PM10—far exceeds national and World Health Organization limits and are considered the main culprit for high pollution of Delhi and its surrounding regions called NCR.

Reasons for Delhi NCR region facing extreme particulate pollution:

Geographical reasons:

  • Location of Delhi: It lies to the northeast of the Thar Desert, to the northwest of the central plains and to the southwest of the Himalayas. As winds arrive from the coasts, bringing with them pollutants picked up along the way, they get ‘trapped’ right before the Himalayas.
  • Cold temperature during winter: During summer hotter air rises higher above the surface and takes the pollutants along with it. However, during October-November, the air is not that hot. The pollutants are trapped and tend to get concentrated at lower levels of the atmosphere, resulting in the smoke and haze situation.
  • Lack of wind esp. after the end of the monsoon: Average wind speed in winter in the Delhi NCR region is one-third of the summer months. This makes the pollutant concentration in the region.
  • Dust Storm: -According to SAFAR (System of Air Quality and Weather Forecasting And Research), 40% of the particulate pollution in Delhi on those specific days could be sourced to a “multi-day dust storm” that originated in the Middle East.

Anthropogenic factors:

  • Stubble burning: The root cause of stubble burning can be traced back to the 1960s-70s when India introduced several measures as part of its Green Revolution to feed its rising population.
  • Governmental policy:In an attempt to address the growing water crisis, the Punjab and Haryana governments introduced laws, which delayed Kharif cropping and thus worsened the pollution due to stubble burning.
  • Manufacturing activity, Power Generation, Construction, and Transport: The Central Pollution Control Board (CPCB) and the National Environmental Engineering Research Institute (NEERI) have declared vehicular emission as a major contributor to Delhi’s increasing air pollution.
  • Minimum Citizen participation: Unlike in other parts of the world, there is little citizens’ movement for controlling pollution.
  • Poor Regulations: Regulation is most often seen as imposing bans, not hand-holding and persuading industry – most of them small factories – into adopting environment-friendly measures
  • India has not recognised in policy and law that air pollution is a killer.

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Indian Express, 05-11-22