Context:

• Delhi’s winter season symbolizes both celebration and concern — vibrant festivals coincide with toxic air pollution.
• In 2025, however, unique meteorological factors like an early monsoon withdrawal, rainfall events, and a transitioning La Niña phase have offered temporary relief.
• Yet, the broader air quality challenge persists, demanding structural policy responses.

The Meteorological Silver Lining:

• Early monsoon withdrawal - A welcome change:
  • The 2025 monsoon withdrew early (last week of September), the earliest since 2002.
  • Benefits:
    • Active winds curtailed pollutant stagnation.
    • Western disturbance-induced rainfall helped wash pollutants away.
  • Significance: Reversal of the recent trend of delayed monsoon withdrawal, which had worsened pollution by compressing the atmospheric boundary layer.
• ENSO and La Niña prospects:
  • India currently experiences El Niño-Southern Oscillation (ENSO)-neutral conditions, trending towards La Niña (with a 71% probability by mid-October 2025).
  • Positive impacts: Recent studies from the National Institute of Advanced Studies (NIAS) indicate that strong La Niña events enhance surface wind speeds, aiding dispersion of particulates.
  • Caution: Weak La Niña, if prolonged, may intensify winter severity, favouring pollution accumulation.

Agricultural and Regional Dynamics:

• Impact of floods and harvest delays: Severe floods in Punjab and Haryana delayed harvests by 1–2 weeks.
• Consequences:
  • Stubble burning delayed, not coinciding with Diwali — temporarily reduced pollution.
  • However, delayed harvest compresses Rabi sowing window, as farmers usually have a tight window of around 45 days to clear fields.
  • Farmers may resort to burning rice stubble, as it is non-usable as fodder due to high silica content.

Firecrackers, Judiciary, and Urban Emissions:

• Judicial intervention and green crackers:
  • The judiciary allowed “green firecrackers” under strict regulation.
  • Despite being “eco-friendly,” they emit 60–70% of pollutants compared to conventional ones.
  • As a result pollution spikes persisted — air quality index (AQI) remained “very poor”, though not “severe,” mainly due to favourable weather.
• Data gaps and AQI misrepresentation:
  • Missing midnight-to-4 am pollution data potentially underreports true AQI peaks.
  • Hourly particulate matter (PM) concentrations reportedly soared to 1000–1800 µg/m³, revealing a deeper, masked pollution crisis.

Structural, Governance Challenges and Solution:

• Short-term fixes vs. long-term strategy: Ad-hoc measures like smoke towers, water sprinkling, or cloud seeding are ineffective.
• The real solution: Lies in source-based mitigation, targeting vehicular, industrial, and agricultural emissions.

Way Forward:

• Adopt airshed-based governance: Airshed management—coordinating emission control across Delhi-NCR and neighbouring states (Punjab, Haryana, UP)—is essential.
• Strengthen agricultural support: Promote in-situ stubble management, and incentivize crop diversification.
• Enhance AQI data transparency: Ensure real-time, uninterrupted monitoring to reflect true pollution levels.
• Implement NARFI vision:
  • The NARFI (National Air Quality Resource Framework of India) developed by NIAS provides a scientific blueprint for sustainable Atmanirbhar air quality management.
  • Its vision is to build national capacity for research, forecasting, and policy coordination.
• Public participation: Encourage community-driven emission reduction through awareness and behaviour change.

Conclusion:

• Delhi’s brief respite in 2025 underscores the influence of natural variability—not policy—on air quality.
• While La Niña and early monsoon withdrawal may offer temporary relief, climate-linked uncertainties and agricultural realities could reverse gains.
• Sustainable clean air demands systemic reform, scientific management, and cooperative federalism, moving beyond symbolic or seasonal interventions.