Archive · 16 Dec 2025
Later-day stubble burning complicates air quality monitoring in India
Farmers in northern India are now burning crop leftovers later in the day, which makes it harder for scientists to track using satellites.
This change started a few years ago, and now most fires happen between 4 p.m.
and 6 p.m.
instead of earlier in the afternoon.
The smoke from these fires spreads across many states and makes the air quality very bad, especially in cities like Delhi.
Scientists are still trying to figure out exactly how much these fires contribute to pollution, but they know it's a big problem.
The later fires might make pollution worse because the air is calmer in the evening, allowing pollutants to build up more easily.
Farmers in northern India are burning crop residue later in the day, shifting from early afternoon to between 4 p.m. and 6 p.m.
This change makes it harder for satellites to track the fires, as most fire-monitoring systems pass over locations only once or twice a day.
The smoke from these fires spreads across Punjab, Haryana, Uttar Pradesh, and Madhya Pradesh, significantly worsening air quality in cities like Delhi.
In 2025, pollution levels exceeded 400 on India's air quality index, prompting school closures and stricter controls on construction activity.
Scientists estimate that stubble burning accounts for 10 to 50% of pollution, with varying contributions depending on the timeframe and other factors.
- Who
- Farmers in northern India, NASA scientists, and Indian researchers
- What
- Shift in stubble burning timing to later in the day, complicating air quality monitoring
- When
- 2025 stubble burning season (October to December)
- Where
- Indo-Gangetic Plain (Punjab, Haryana, Uttar Pradesh, Madhya Pradesh)
- Why
- Change in farmers' behavior, leading to later-day fires that are harder to monitor with current satellite systems
- Region Affected
- Indo-Gangetic Plain (Punjab, Haryana, Uttar Pradesh, Madhya Pradesh)
- Typical Stubble Burning Season
- October to December
- Previous Fire Timing
- 1 p.m. to 2 p.m. local time
- Current Fire Timing
- 4 p.m. to 6 p.m. local time
- Satellite Used for Analysis
- GEO-KOMPSAT-2A (South Korean geostationary satellite)
- Air Quality Index (AQI) Peak
- Exceeded 400 in 2025
- Stubble Burning Contribution to Pollution
- 10 to 50% (varies by study and timeframe)
