Delhi's Air Quality Deteriorates Sharply as Diwali Approaches

Strategic Insights -

Delhi's air quality reached a critical level on Saturday, with the 24-hour average air quality index touching 199, just shy of the "poor" category. The sharp deterioration reflects typical pre-winter meteorological patterns, which create atmospheric conditions that trap pollutants near the ground. The Air Quality Early Warning System forecast further deterioration, predicting poor air quality from Sunday through the week ahead, as calm wind conditions persist and temperature inversion concentrates pollutants near the surface.

Key Takeaways:

  • Delhi's air quality index touched 199 on Saturday, just one point shy of the "poor" category, marking a significant jump from 170 on Friday and 100 the previous day.
  • The sharp rise reflects typical meteorological patterns for mid-October, when falling temperatures create atmospheric conditions that prevent pollutants from dispersing.
  • Low wind speeds, combined with temperature inversion, create a "lid" that concentrates pollutants near the surface, making the air quality worse.
  • Northwesterly winds during this season carry smoke from crop stubble burning in Punjab and Haryana, adding to the city's pollution level.
  • The Air Quality Early Warning System bulletin warned that "air quality is very likely to be in the poor category from Sunday to Tuesday," with the outlook for the subsequent six days also indicating poor conditions.
  • Delhi typically sees a sharp spike in pollution levels during Diwali due to firecracker burning, compounding the meteorological factors.
  • The city last recorded poor air on June 11, when the AQI stood at 245, and has enjoyed 122 consecutive days of cleaner air since then.

Statistics:

  • 24-hour average air quality index: 199
  • Wind speed on Saturday: 6-9 kmph
  • Maximum temperature on Saturday: 30.3°C, 3.9°C below normal
  • Minimum temperature on Saturday: 19.4°C, 1.6°C below normal
  • Delhi's air quality index improvement since June 11: 122 consecutive days of cleaner air
  • Breakdown of Delhi's air quality index improvement:

+ 77 satisfactory days

+ 45 moderate days

+ 0 poor days since June 11

Sources:

  • Central Pollution Control Board's daily bulletin
  • Air Quality Early Warning System bulletin
  • India Meteorological Department forecast
  • Hindustan Times.