"CAQM Re-tests Satellite Protocol as Stubble Burning Data Shows Divergence"
Burnt Area Assessment
satellite-based mapping of total agricultural area already burnt, distinct from active fire detection.
Mid-Infrared Burn Index (MIRBI)
spectral index using mid-infrared reflectance to identify charred vegetation and soil from satellite imagery.
Delhi's air quality crisis is structurally rooted in its geography and inter-state governance architecture. The city's airshed spans Punjab, Haryana, Rajasthan, and Uttar Pradesh, making unilateral state-level action insufficient. Particulate matter (PM2.5 and PM10) routinely breaches National Ambient Air Quality Standards (NAAQS), set at 40 µg/m³ and 60 µg/m³ (annual mean) respectively, as notified by the Central Pollution Control Board (CPCB).
The institutional architecture has evolved through successive judicial and legislative interventions. The M.C. Mehta v. Union of India series was foundational. Parliament replaced the court-constituted Environment Pollution (Prevention and Control) Authority (EPCA) in 2021 with the Commission for Air Quality Management in National Capital Region and Adjoining Areas (CAQM), established through a dedicated Act. CAQM holds binding, quasi-federal enforcement authority across Delhi and four adjoining states. The Graded Response Action Plan (GRAP), first notified in 2017, provides a tiered restriction framework triggered by Air Quality Index (AQI) thresholds.
Satellite remote sensing has become a core tool in environmental monitoring across India. Indian Remote Sensing (IRS) satellites operated by ISRO and the National Remote Sensing Centre (NRSC) are used for crop productivity assessment, groundwater mapping, mineral exploration, and land surface temperature measurement. More recently, satellite data has been extended to detect and quantify crop residue burning, an application that requires distinguishing active fire events from the total area of burnt agricultural land, two distinct but complementary measurements.
Paddy stubble burning in Punjab and Haryana between mid-September and late November is one of the largest seasonal contributors to Delhi-NCR's air pollution. On peak days in October and November, farm fire emissions can account for up to 35 per cent of Delhi's pollution load. Farmers burn paddy stubble to quickly clear fields before the next sowing cycle, creating a narrow window in which millions of tonnes of crop residue are set alight across the two states.
Monitoring this burning has relied on two distinct methods. The first is active fire count monitoring, which uses satellite thermal sensors to detect fires burning at the moment the satellite passes overhead. This method has a known limitation: satellites have fixed overpass windows, meaning fires that start and end between two passes go undetected. The Supreme Court has scrutinised this undercounting since 2024.
The second method is burnt area assessment, developed to plug the gaps left by overpass timing. …
In which of the following activities are Indian Remote Sensing (IRS) satellites used?
1.Assessment of crop productivity
2.Locating groundwater resources
3.Mineral exploration
4.Telecommunications
5.Traffic studies
Select the correct answer using the code given below.
For the measurement/estimation of which of the following are satellite images/remote sensing data used?
1.Chlorophyll content in the vegetation of a specific location
2.Greenhouse gas emissions from rice paddies of a specific location
3.Land surface temperatures of a specific location
Select the correct answer using the code given below.
Consider the following statements regarding Indian Remote Sensing (IRS) satellites and their applications:
1.IRS satellites are used for assessment of crop productivity.
2.IRS satellites are used for locating groundwater resources.
3.IRS satellites are used for mineral exploration.
4.IRS satellites are used for telecommunications.
Which of the statements given above are correct?
Consider the following statements regarding satellite remote sensing data and its applications:
1.Satellite images can be used to estimate chlorophyll content in vegetation at a specific location.
2.Satellite remote sensing data can be used to estimate greenhouse gas emissions from rice paddies.
3.Land surface temperatures of a specific location can be measured using satellite images.
4.Satellite data can map burnt agricultural areas using mid-infrared spectral indices.
Which of the statements given above are correct?
Consider the following statements regarding the Burnt Area Assessment Protocol developed for monitoring crop residue burning in India:
1.It uses the Mid-Infrared Burn Index (MIRBI) method to detect burnt agricultural areas.
2.It relies on data from the European Space Agency's Sentinel-2 satellite at a spatial resolution of 20m × 20m.
3.It detects active fires at the moment of satellite overpass.
4.It was developed jointly by NRSC/ISRO, IARI, and State Remote Sensing Centres of Punjab and Haryana.
Which of the statements given above are correct?
With reference to the Commission for Air Quality Management (CAQM), consider the following statements:
1.CAQM was established by Parliament through a dedicated Act in 2021.
2.CAQM's Directions are legally binding on state pollution control boards in the NCR region.
3.CAQM replaced the Environment Pollution (Prevention and Control) Authority (EPCA), which was itself a statutory body created by Parliament.
4.CAQM monitors active fire counts in collaboration with bodies under the Agriculture Ministry.
Which of the statements given above are correct?
Match the following monitoring methods used for crop residue burning with their defining characteristics:
Method — Characteristic
1.Active Fire Count — (a) Maps total agricultural area already burned using spectral indices
2.Burnt Area Assessment — (b) Detects fires burning at the moment of satellite overpass
3.Ground Truthing — (c) On-site physical verification to validate satellite-derived data
Which of the following is the correct matching?
Want the full note, Prelims Facts & MCQ answers?
Create a free account — takes less than a minute.
Create free account