No relief for Delhi as stubble burning pushes air quality toward severe levels

The alarming rise in pollution levels is driven by a surge in crop-burning incidents. On Tuesday, 1,483 fire cases were reported.

In Short

• The stubble burning contribution is predicted to rise to around 15%
• On Tuesday, 1,483 stubble fire cases were reported
• This troubling trend is exacerbated by agricultural practices in Punjab and Haryana

The escalating air pollution in Delhi has taken a worrying turn, according to the latest data from the Indian Institute of Tropical Meteorology (IITM), Pune.

The contribution of stubble burning to Delhi's pollution reached a season-high of 8%, up from 3.2% on Monday. With the onset of winter, this figure is expected to rise significantly in the coming days, posing severe risks to air quality and public health.

On Wednesday, the stubble burning contribution is predicted to rise to around 15%, increasing further to approximately 21% on Thursday and stabilising near 20% mark on Friday.

This alarming rise in pollution levels is driven by a surge in crop-burning incidents. On Tuesday, 1,483 fire cases were reported, the highest number for the season and a steep increase from Monday's 544 incidents.

The previous high was recorded on October 12, with 964 cases. This troubling trend is exacerbated by agricultural practices in Punjab and Haryana, and is spreading to other states like Madhya Pradesh, Uttar Pradesh, and Rajasthan.

As stubble burning intensifies, it is poised to overtake vehicular pollution as the primary contributor to Delhi's smog. The contribution of transport pollution is expected to be 13.5%, 14.6%, and 15.1% on Wednesday, Thursday, and Friday, respectively. While vehicle emissions have been the dominant factor until now, the rapid increase in crop-residue fires is changing the dynamics of pollution sources.

Delhi’s air quality is forecasted to deteriorate significantly in the coming days, falling into the "Very Poor" category from October 24 to October 26, 2024. This troubling trend is expected to worsen, with air quality potentially reaching the "Severe" category. Meteorological conditions, including calm overnight winds, are not conducive to pollutant dispersion, trapping pollutants close to the ground.

Surface winds in Delhi varied in direction and maintained a speed of 6 to 12 km/h on October 23, accompanied by morning mist and clear skies during the day. On October 24, winds are expected to come from the north-northwest and north at similar speeds. By October 25, wind direction will become variable, with speeds between 6 to 14 km/h. On October 26, winds will shift to an east-southeast direction, slowing to 6 to 8 km/h, further hindering pollution dispersion.

The predicted maximum mixing depth will decrease from 1,500 meters on October 23 to 1,250 meters by October 26. Meanwhile, the ventilation index, combined with average wind speeds below 10 kmph will create an unfavourable environment for clearing pollutants from the air.

With air quality plummeting and no immediate relief in sight, Delhi residents are advised to take precautions, especially those with health vulnerabilities. Reducing outdoor activities during this period can help mitigate the adverse health effects of poor air quality.