Delhi's air quality experienced a significant downturn in November 2025, with pollution levels nearly doubling compared to the previous month. This deterioration has propelled Delhi to the fourth most polluted city in India, while Ghaziabad has topped the list as the most polluted city.

Ghaziabad recorded a monthly average PM2.5 concentration of 224 micrograms per cubic meter in November, exceeding national air quality standards on all 30 days of the month. Delhi ranked fourth with a monthly average PM2.5 concentration of 215 micrograms per cubic metre, nearly double its October average of 107.

Cities in Crisis

The Centre for Research on Energy and Clean Air (CREA) reported that 20 out of 29 cities in the National Capital Region (NCR) recorded higher pollution levels this November compared to last year. Nineteen cities exceeded the PM2.5 standard every single day in November. Besides Ghaziabad and Delhi, other cities in the top 10 most polluted list included Noida, Bahadurgarh, Hapur, Greater Noida, Baghpat, Sonipat, Meerut, and Rohtak. Uttar Pradesh accounted for six of these cities, Haryana for three, and Delhi for one.

Stubble Burning's Diminished Role

Interestingly, stubble burning contributed less to Delhi's pollution this year, averaging 7% in November, a significant decrease from 20% last year. The peak contribution reached 22%, considerably lower than last year's 38%. Despite the reduced impact from stubble burning, 20 out of 29 NCR cities recorded higher pollution levels than the previous year. This suggests that local sources of pollution within Delhi and the NCR are major contributors to the worsening air quality.

Factors Behind Delhi's Air Pollution

Several factors contribute to Delhi's persistent air pollution problem. These include:

• Vehicular Emissions: A large number of vehicles, many of which are old and poorly maintained, release high levels of pollutants.
• Industrial Pollution: Industries in and around Delhi often fail to adopt environment-friendly fuels and techniques, emitting harmful gases.
• Construction Dust: Construction activities generate significant amounts of dust, which contribute to air pollution.
• Weather Conditions: During winter months, cooler temperatures and low wind speeds trap pollutants near the ground.
• Firecrackers: The bursting of firecrackers during festivals adds to the existing pollution load.
• Landfill Fires: Burning of municipal solid waste at landfill sites further degrades air quality.

Health Impacts and Mitigation Measures

High levels of air pollution pose significant health risks, including respiratory illnesses, cardiovascular diseases, and other health problems. To mitigate these effects, authorities recommend wearing masks and avoiding prolonged outdoor activities during periods of high pollution.

The government has also implemented measures to control air pollution, such as:

• Enforcing Bharat Stage VI emission norms for vehicles.
• Promoting the use of electric vehicles.
• Banning firecrackers during Diwali.
• Spraying water to suppress dust.

While these measures have had some impact, the air quality in Delhi-NCR remains a major concern.

Regional Comparison

While Delhi's air quality worsened, other regions fared differently. Rajasthan had the highest number of cities breaching air quality standards in November, while Meghalaya's capital, Shillong, was the cleanest.

The air quality crisis in Delhi-NCR highlights the urgent need for more effective and sustainable solutions to combat air pollution. A coordinated effort from the government, industries, and the public is crucial to ensure cleaner air for the future.