Delhi Breathes Easier for Now: Winds Bring Respite, But Post-Oct 15 Haze Looms Large

Delhi, a city often synonymous with challenging air quality, experienced a welcome breath of fresh air over the past weekend. Residents enjoyed a temporary reprieve as the Air Quality Index (AQI) notably improved, settling into the 'moderate' category. On Sunday, the city's average AQI was recorded at a relatively manageable 149, a stark contrast to the higher pollution levels often seen.

This much-needed improvement is primarily attributed to consistent, strong winds that have been sweeping across the National Capital Region.

These winds act as natural purifiers, efficiently dispersing accumulated pollutants and preventing them from lingering in the lower atmosphere. The meteorological conditions have been favorable, allowing for better ventilation and dilution of emissions.

However, environmental experts and agencies like SAFAR (System of Air Quality and Weather Forecasting And Research) and the India Meteorological Department (IMD) issue a cautionary note: this clear sky might be short-lived.

The respite is projected to be temporary, with a significant deterioration in air quality anticipated shortly after October 15. This date often marks a critical turning point as winter approaches.

The primary culprits behind the impending decline are a combination of meteorological shifts and seasonal agricultural practices.

Post-mid-October, wind speeds are expected to significantly decrease, creating conditions conducive to pollutant accumulation. Concurrently, the annual practice of stubble burning in neighbouring states, particularly Punjab and Haryana, is set to intensify. The smoke plumes from these farm fires, carried by prevailing winds, will inevitably drift towards Delhi, adding a substantial load to its already strained air quality.

While stubble burning is a major seasonal factor, Delhi's baseline pollution levels are always influenced by a myriad of local emission sources.

Vehicular exhaust, industrial emissions, dust from construction activities, and waste burning collectively contribute to a persistent blanket of smog. When adverse weather conditions combine with external factors like farm fires, the air quality can rapidly plunge into 'poor' or even 'very poor' categories, posing significant health risks to the populace.

Authorities have already implemented the Graded Response Action Plan (GRAP) to combat pollution, which includes various measures depending on the severity of the AQI.

As the situation is expected to worsen, stricter stages of GRAP might need to be enforced to mitigate the impact. The forecast for the immediate future indicates 'moderate' air quality for Monday, potentially slipping to 'poor' by Tuesday, signaling the beginning of the challenging pollution season that grips the region every autumn and winter.