Model Answer

Introduction

Delhi's air quality deteriorates annually during the post-monsoon months, turning “poor” to “severe” due to a complex interaction of meteorological factors and anthropogenic emissions. In October 2025, Delhi recorded an AQI of 211 (poor category), prompting the activation of Stage 1 of the Graded Response Action Plan (GRAP).

Body

1. Causes of Deteriorating Air Quality:

   1. Vehicular and Industrial Emissions: High traffic density, especially diesel vehicles, release NOx and VOCs that react under sunlight to form ground-level ozone, a harmful secondary pollutant.
   2. Particulate Matter (PM10 and PM2.5): Dust from roads, construction sites, and open burning, coupled with reduced wind speed during October, increases particulate concentration.
   3. Stubble Burning in Neighboring States: Post-harvest burning of rice stubble in Punjab, Haryana, and Western UP adds a significant transboundary load of PM2.5 and PM10. Although only 552 farm fires were reported between mid-September and mid-October, the peak is expected in November.
   4. Meteorological Factors: Stable atmospheric conditions, low boundary layer height, and calm winds hinder dispersion of pollutants, causing accumulation near the surface.

2. Effectiveness of GRAP:

   Positive Aspects:

   • Provides a graded, pre-emptive mechanism to control pollution, activating measures like halting construction, mechanized road cleaning, and banning DG sets.
   • Enhances institutional coordination between CPCB, CAQM, and local authorities.

   Limitations:

   • Reactive rather than preventive: Action starts only after AQI crosses thresholds.
   • Weak enforcement: Local-level compliance is inconsistent.
   • Limited focus on root causes: It cannot address stubble burning, vehicular congestion, or waste burning effectively without long-term structural changes.

Way Forward:

• Sustainable crop residue management through incentives and biomass-based industries.
• Transition to electric public transport and stricter vehicular emission norms.
• Dust control and construction waste management in urban areas.
• Regional air-shed management approach integrating neighboring states.

Conclusion/Way Forward

Delhi's pollution crisis is not a local phenomenon but a regional environmental challenge. While GRAP has provided an institutional framework for emergency response, lasting improvement requires preventive, multi-sectoral, and cooperative measures addressing both rural and urban emission sources.