Two years after SC flag, no final protocol to measure burnt area of farm fires

Why in the News

India counts farm fires by satellite every season, but it still has no finalised measure of how much farmland is actually burnt. The Indian Agricultural Research Institute (IARI) has stated that burnt area estimates for Punjab and Haryana remain “unverified” and “unfinalised“, nearly two years after the Supreme Court called burnt area the most important measure of farm fires. Falling fire counts therefore cannot confirm that stubble burning has declined.

What is “burnt area”, and how does it differ from a fire count?

1. What it is: Burnt area is the extent of farmland actually burnt in a season. It is like measuring the damage instead of counting the accidents.
2. Active fire count: It records a fire only if a satellite passes overhead when the fire is visible. IARI publishes daily bulletins from National Remote Sensing Centre (NRSC) data.
3. Burnt area mapping: It identifies burnt land after the event, so it captures the cumulative extent, including small or short fires that satellites miss.
4. The takeaway: A falling fire count can hide burning that continues outside the satellite’s view.

What did the Supreme Court flag, and what has happened since?

1. Supreme Court scrutiny: In November 2024, a two judge Bench questioned the Commission for Air Quality Management (CAQM), the Delhi region’s air quality regulator. Data had shown burnt area rising as fire counts fell.
2. Court’s observation: The Bench said: “The extent of fire can be demonstrated only by a burnt area… That’s most important.”
3. Two protocols: A standard protocol for counting active fires has existed since 2021. CAQM formed an expert committee under the NRSC in January 2024 to standardise burnt area mapping.
4. IARI’s position: IARI says it is “only researching” satellite mapping and “there is yet no standardized methodology”. Its estimates for 2025 and the four preceding years are not authenticated.

Why is the burnt area protocol still not final?

1. Satellites used: The method uses Sentinel-2 satellites of the European Space Agency. They revisit an area every five days and detect burn scars through infrared imagery.
2. Validation: The protocol is still being tested. Satellite maps are compared with independent reference data to find missed fires and wrongly marked areas.
3. Ground truthing gap: In CAQM’s ground truthing, meaning field checks of satellite readings, teams could not detect more than 50% of satellite detected fires.
4. Mixed fields: Standing crops, harvested straw and scorched earth lie close together at harvest, so satellite models confuse burnt fields with dry residue.

What does the evidence show about fire counts and burnt area?

1. Haryana: Recorded fire incidents more than halved in 2025, but burnt area rose by nearly a quarter, a report by the International Forum for Environment, Sustainability and Technology (iFOREST) found.
2. Punjab: Fire incidents also more than halved, but burnt area fell by only about 15%.
3. Evening fires: Over 90% of large fires occurred after 3 pm, outside the overpass times of polar orbiting satellites, which cross a place only at fixed hours.
4. Shift in timing: A Space Applications Centre study, using geostationary satellites that watch one region continuously, found peak burning moving to late afternoon and evening.

Challenges

1. No official baseline: Without an authenticated burnt area figure, governments cannot tell whether stubble burning fell or only moved out of satellite view.
2. Pollution share unclear: Without a finalised burnt area measure, agencies cannot reliably estimate how much stubble burning contributes to air pollution.
3. Divided responsibility: NRSC supplies data, IARI publishes bulletins and CAQM validates maps, so no single body owns the final figure.

Way Forward

1. Deadline for the protocol: CAQM and NRSC should set a date to complete validation and adopt the burnt area protocol.
2. Two metrics together: IARI’s bulletins should report validated burnt area alongside fire counts.
3. Continuous monitoring: Agencies should add geostationary imagery to track fires lit after the counting satellites have passed.

Conclusion

Fire counts remain the only official yardstick of stubble burning, and the method to measure burnt area is still being validated. Whether CAQM adopts a final protocol before the next paddy harvest is the thing to watch.

Key numbers

1. Haryana, 2024 to 2025: Fire incidents 1,406 to 662; burnt area 7,117 sq km to 8,812 sq km (iFOREST).
2. Punjab, 2024 to 2025: Fire incidents 10,909 to 5,114; burnt area 23,262 sq km to 19,757 sq km (iFOREST).
3. Paddy area burnt each season: 49.1% in Punjab and 17.69% in Haryana (IARI study, 2018 to 2021).

Matching Previous Year Question

“[2021, GS3, 10 marks] Describe the key points of the revised Global Air Quality Guidelines (AQGs) recently released by the World Health Organisation (WHO). How are these different from its last update in 2005? What changes in India’s National Clean Air Programme are required to achieve these revised standards?”