Delhi Air Quality Turns Moderate as Crop Residue Burning Reported Across Six States

Delhi’s air quality slipped into the moderate category on Wednesday, September 30, after remaining satisfactory for five consecutive days. The city recorded an Air Quality Index (AQI) of 129, indicating a rise in pollution levels as crop-residue burning incidents were detected across several states.

Data from the ICAR-Indian Agricultural Research Institute (IARI) showed that satellites detected 19 stubble-burning events across six states on Wednesday. The findings have renewed attention on seasonal pollution sources as northern India approaches the winter months, when unfavourable weather conditions can contribute to higher pollution levels.

The latest readings also highlight how air quality can vary across different parts of the capital, even when the city’s overall average remains within one category.

Punjab and Uttar Pradesh Record the Highest Number of Fires

Of the 19 crop-residue burning events detected on September 30, Punjab and Uttar Pradesh reported seven each. Madhya Pradesh accounted for four incidents, while Haryana recorded one.

Between September 15 and 30, a total of 114 such events were detected across the six states. Punjab recorded 59 incidents, followed by Uttar Pradesh with 32 and Madhya Pradesh with 17. Haryana reported three, Rajasthan two and Delhi one.

These figures are based on satellite observations and represent detected events during the specified period. They do not, by themselves, establish how much pollution reached Delhi from each location.

Delhi AQI Rises After Five Days of Satisfactory Air

According to the Central Pollution Control Board (CPCB), an AQI of 129 places Delhi in the moderate category. Under the national classification system, readings between 101 and 200 are considered moderate, while 51 to 100 fall under the satisfactory category.

The city’s monitoring network showed differences between locations. Of the 45 monitoring stations, 42 recorded moderate air quality, while three reported satisfactory conditions. The IIT Delhi station registered an AQI of 207 at 6 pm, placing it in the poor category.

This variation demonstrates why citywide averages may not fully reflect the air quality experienced by residents in individual neighbourhoods.

Weather Conditions Could Limit Pollution Dispersion

Weather conditions are also an important factor in determining how pollution behaves. The Air Quality Early Warning System indicated that Delhi’s air quality was likely to remain moderate from October 1 to 3 and for the following six days.

The forecast pointed to a ventilation index below 6,000 square metres per second and average wind speeds of less than 10 kilometres per hour. Such conditions can restrict the movement and dispersal of pollutants, allowing them to remain concentrated near the surface.

No rainfall was recorded in Delhi during the 24 hours ending at 8:30 am on Wednesday, according to the reported weather data.

Why Crop Residue Burning Matters

Farmers sometimes burn leftover crop material to clear fields before preparing them for the next cultivation cycle. The practice can contribute to regional air pollution, particularly when emissions coincide with weak winds and other pollution sources.

However, Delhi’s air quality is influenced by multiple factors, including vehicles, industrial emissions, construction dust, waste burning and weather patterns. Crop-residue burning is one part of a wider pollution challenge.

Focus Turns to the Coming Weeks

With the seasonal transition underway, the latest AQI reading serves as an early indication of the challenges that may emerge in the coming weeks. Monitoring fire incidents, improving access to residue-management alternatives and coordinating action across states remain important parts of addressing the issue.

The immediate outlook suggests that weather conditions may not support rapid pollutant dispersal. Continued monitoring will be essential to understand how Delhi’s air quality changes as the winter pollution season approaches.