Residents of the national capital breathed a slight sigh of relief on Monday as the city's overall air quality index (AQI) showed a marked improvement, dropping into the 'Poor' category. However, this reprieve is expected to be short-lived, with forecasting agencies predicting a deterioration in the coming days.
Current Air Quality Status and Contributing Factors
According to data from the Central Pollution Control Board (CPCB), the 24-hour average AQI for Delhi was recorded at 234 on Monday, November 11. This placed the city in the 'Poor' category, a significant improvement from the 'Very Poor' levels witnessed over the preceding weekend. The System of Air Quality and Weather Forecasting and Research (SAFAR) also reported a similar figure, with its monitoring station at Delhi University recording an AQI of 234.
Meteorological conditions played a crucial role in this temporary improvement. Favorable wind speeds helped in the dispersion of pollutants, preventing their accumulation over the city. However, scientists have flagged a concerning trend: the contribution of stubble burning to Delhi's PM2.5 pollution. SAFAR data indicated that the share of stubble burning in the capital's PM2.5 concentration was around 21% on Monday. This external factor, combined with local emissions, remains a persistent challenge.
Grim Forecast for the Coming Days
The improved air quality is unlikely to last. Both SAFAR and the Early Warning System for Delhi have issued alerts forecasting a likely decline starting Tuesday. The primary reason cited is a change in weather patterns. Wind speeds are expected to slow down significantly, and the wind direction is predicted to shift to north-westerly. This combination is detrimental as it will not only reduce the natural dispersal of existing pollutants but also transport smoke from ongoing stubble burning in Punjab and Haryana directly towards the National Capital Region (NCR).
These stagnant conditions are expected to lead to the accumulation of particulate matter. Forecasts suggest that the AQI could slip back into the 'Very Poor' category (301-400) by Wednesday, November 13. Authorities are closely monitoring the situation, as prolonged exposure to such air quality poses serious health risks, particularly for children, the elderly, and individuals with pre-existing respiratory or cardiovascular conditions.
Ongoing Measures and Public Health Advisory
In response to the fluctuating air quality, the Commission for Air Quality Management (CAQM) continues to enforce Stage II of the Graded Response Action Plan (GRAP) across the NCR. This stage includes a set of anti-pollution measures designed to prevent further deterioration. Key actions under GRAP Stage II involve:
- Strictly enforcing bans on coal and firewood use in eateries and other commercial establishments.
- Enhancing parking fees to discourage private vehicle usage.
- Increasing the frequency of mechanized cleaning and water sprinkling on roads to suppress dust.
Despite these measures, the looming deterioration highlights the complex and trans-boundary nature of Delhi's winter pollution crisis. While local sources like vehicle emissions, construction dust, and industrial activity are major contributors, the seasonal impact of farm fires in neighboring states adds a critical and uncontrollable dimension. Health experts advise vulnerable groups to limit prolonged outdoor exposure, use N95 or N99 masks when outside, and avoid strenuous exercise in the open during early morning and late evening hours when pollution levels tend to peak.
The coming week will be a critical test of both meteorological fortune and the efficacy of existing pollution control protocols as Delhi braces for another potential spike in its toxic air.
