Delhi's Air Quality Post-Diwali: 2nd Cleanest Since 2015, Thanks to Winds

Discover how Delhi managed to keep its air quality relatively clean post-Diwali, making it the second cleanest since 2015, with insights into the impacting factors.

P24 News Media

November 02, 2024

1 minute

India

Delhi's Air Quality Post-Diwali: 2nd Cleanest Since 2015, Thanks to Winds

Delhi has achieved a notable feat with its air quality marking the second cleanest record following Diwali celebrations since 2015. Rather than slipping into a severe AQI status, the city has maintained a “very poor” classification, thanks primarily to strong winds that exceeded 16 kilometers per hour, allowing for effective ventilation.

Air Quality Index Trends

On Thursday evening, the AQI began its ascent, starting from 328 and climbing to 338 by midnight, peaking at 362 by Friday morning. Surprisingly, a shift in weather patterns provided relief from the typical post-Diwali pollution, leading to an AQI drop to 339 by the afternoon and further to 323 by the evening.

Role of Weather in Air Quality

Mahesh Palawat, vice president at Skymet meteorology, elaborated on the relationship between air temperature and pollution levels. Warmer temperatures contribute to a higher mixing height which facilitates the dispersion of pollutants. Conversely, colder temperature leads to a reduced wind speed, trapping pollutants near the surface, a situation known as temperature inversion.

Diwali Pollution Source Dynamics

Although the use of fireworks, increasing stubble burning, and local emissions contributed significantly to the pollution levels, which surged late Thursday night into Friday morning, sustained winds helped in alleviating the situation. Noteworthy is the increase in stubble burning contributing to PM2.5 levels on Diwali day, where its influence soared to 27.61%, contrasting sharply with only 1.8% just days before.

Future Air Quality Concerns

Despite the commendable post-Diwali air quality, there are underlying concerns regarding hourly spikes in PM2.5 levels in particular areas of Delhi, often exceeding national safety limits by over 30 times. Experts stress that while immediate conditions have improved, persistent local and regional pollution remains a pressing issue, particularly with winter months approaching which typically worsen air quality.

Impact of Local Pollution

Anumita Roychowdhury from the Centre for Science and Environment remarks on the worrying trend of poor air quality days throughout October, signaling an urgent need for addressing the larger pollution contributors beyond festive activities. It reinforces the notion that the conditions of natural ventilation, while currently favorable, may not last with the expected onset of winter, alongside increased regional pollution.

To sum up, the 2024 post-Diwali air quality in Delhi, while commendable compared to previous years, illustrates the ongoing challenges in managing air pollution effectively. The interactions between weather conditions and local pollution sources will be crucial in determining how air quality fluctuates as the city moves further into winter.