Delhi's Pollution Levels Rocket to "Poor" Zone as Toxic Air Returns

Strategic Insights -

Delhi's 20 million-plus residents are bracing themselves for months of toxic air as the city's pollution levels rocketed into the "poor" zone for the first time in four months on Tuesday. This comes as dipping temperatures, dusty winds, and the impending Diwali festivities threaten to drive up pollution levels to the worst in the world. The city's average 24-hour air quality index (AQI) hit 211 at 4 pm on Tuesday, according to the Central Pollution Control Board's (CPCB) daily bulletin. Experts warn that Delhi's problem will only get more acute in the coming weeks, with Diwali around the corner and stubble fires already peppering the farmlands of Punjab.

Key Takeaways:

  • Delhi's pollution levels reached a "poor" zone for the first time in four months on Tuesday, with an average AQI of 211.
  • The city is expected to experience months of toxic air, with pollution levels driven up by smoke from firecrackers on Diwali, lower temperatures, slowing winds, and smoke from stubble fires in upwind Punjab and Haryana.
  • The Commission for Air Quality Management (CAQM) ordered the enforcement of Graded Response Action (Grap) Stage 1, which includes preventive measures such as periodic mechanized sweeping and water sprinkling on roads.
  • Grap Stage 1 is typically enforced when the AQI crosses 200, with Stage 2 (very poor) measures invoked when the AQI crosses 300, Stage 3 (severe) when the AQI crosses 350, and Stage 4 (severe-plus) when the AQI is above 400.
  • The Supreme Court revised the thresholds for the last two categories in 2023, which would earlier be invoked at 400 and 450 respectively.
  • Forecasts by the Centre's Air Quality Early Warning System warn that the air will only get more noxious, with "very poor" AQI also likely around or after Diwali.
  • Stubble fires in Punjab have already clocked 70 farm fires over the past week, with 31 on Tuesday alone.
  • Delhi's top contribution to PM 2.5 on Monday was 19.8% from the transport sector, followed by Gurugram (9.3%) and Delhi's residential sector (5.1%).
  • Delhi's maximum temperature stood at 32.6°C on Tuesday, forecast to rise further and possibly touch 34°C by Wednesday.

Statistics:

  • Delhi's 24-hour AQI reached 211 on Tuesday.
  • The CPCB classified the AQI as "poor" for the first time in four months.
  • The Grap Stage 1 measures include 27 preventive measures such as periodic mechanized sweeping and water sprinkling on roads.
  • The AQI is forecast to worsen, with "very poor" AQI also likely around or after Diwali.
  • Stubble fires in Punjab have already clocked 70 farm fires over the past week, with 31 on Tuesday alone.
  • Delhi's top contribution to PM 2.5 on Monday was 19.8% from the transport sector.
  • The Supreme Court revised the thresholds for Grap Stage 3 and 4 in 2023.

Sources:

  • Hindustan Times, "Delhi's pollution levels rocket to 'poor' zone as toxic air returns"