Every year, as the winter months approach, Delhi and its surrounding satellite cities find themselves enveloped in a familiar and distressing phenomenon: a thick, toxic haze that severely degrades air quality. This annual crisis brings with it burning eyes, sore throats, and a pervasive sense of discomfort for the city’s residents. In recent days, air pollution levels in Delhi have fluctuated between the "poor" and "very poor" categories, setting off alarms across environmental monitoring stations. The situation took a particularly sharp turn for the worse following Diwali, one of India’s most widely celebrated festivals, when fireworks lit up the skies and filled the air with smoke. Media reports declared this the worst post-Diwali air quality Delhi had experienced in four years, thrusting the city once again into its cyclical battle with air pollution.
The causes behind Delhi’s toxic air are multifaceted and interconnected, illustrating why the problem is so stubborn and complex. The city’s smog is not the result of a single source but rather a combination of factors that come together to create hazardous conditions. Firecrackers during festivals, emissions from the city’s dense vehicular traffic, and the widespread burning of crop residue—known as stubble burning—in the neighboring agrarian states of Punjab, Haryana, and Uttar Pradesh all contribute significantly. Compounding the problem are climatic factors: the onset of winter brings colder temperatures and low wind speeds, which trap pollutants close to the ground and prevent their dispersion, worsening the air quality further.
This year, these same elements seem to be at play, but there is some disagreement regarding their individual contributions. Indian media outlets, citing climate research firms, have reported a significant 77% decline in stubble-burning incidents compared to previous years. They attribute this drop to the devastating floods that ravaged crops in the region earlier in the year, which left much farmland unusable and reduced the need for post-harvest field clearing. As a result, these reports suggest that firecrackers were the main culprit behind the spike in pollution during the festive period.
However, official data from Punjab paints a different picture. According to the Punjab Pollution Control Board, stubble-burning incidents have actually increased threefold in the last ten days, with over 350 cases reported—rising sharply from just 116 cases recorded until mid-October. This discrepancy highlights the challenges in accurately assessing pollution sources and underscores the ongoing persistence of crop burning in the region.
Efforts to curb stubble burning have been underway for several years. Authorities have launched targeted campaigns to raise awareness about its detrimental environmental impact and have promoted the use of machinery as a cleaner alternative for clearing fields. These initiatives have yielded some positive results; for example, Punjab recorded 10,909 farm fire incidents last year, a significant decrease from the 36,663 cases reported in 2023. Yet, despite this progress, stubble burning continues largely because it remains the most affordable and convenient method for farmers to prepare their land for the next crop cycle.
While governments at various levels have promised to provide machinery and financial incentives to discourage crop burning, tangible changes on the ground have been limited. Many farmers find the alternatives either too expensive or inaccessible, perpetuating the cycle of burning that contributes so heavily to Delhi’s pollution woes.
Another major contributor to the seasonal spike in pollution is the use of firecrackers during Diwali. Just days before the festival, India’s Supreme Court relaxed a five-year ban on the sale and bursting of firecrackers in Delhi and its neighboring regions. The court permitted the use of “green crackers”—fireworks designed to be less polluting—for a limited period of six hours over two days. However, experts criticized this decision, pointing out that green crackers reduce pollution by only 20 to 30 percent and still emit harmful particles that degrade air quality.
In reality, the festive period saw widespread disregard for these restrictions. Fireworks displays began early in the morning and continued late into the night, often exceeding the court-mandated time limits. Furthermore, not all firecrackers used were green variants; BBC reporters observed more polluting crackers being openly sold in shops across the capital in the days leading up to Diwali. This rampant violation of guidelines contributed significantly to the spike in pollution immediately following the festivities.
The consequences of this deteriorating air quality are severe and immediate for the residents of Delhi. Many have reported symptoms such as persistent coughing, watery eyes, and difficulty breathing. Medical professionals warn that prolonged exposure