Environment › Climate negotiations and finance
Mitigation: industry, methane and carbon removal
Cutting emissions where it is hardest and taking carbon back out of the air: steel, cement and other heavy industry, methane and cooling gases, shipping and aviation, and carbon capture, removal and geoengineering. It serves GS3 answers on climate change and industry.
All 3 subjects shown; the 2 that changed from 1 to 15 September 2026 are marked.Show only these
Carbon lock-in
Copy link to Carbon lock-inPrelims and Mains
A steel plant is not a decision taken again each year: it is taken once, when the plant is built or relined, and carbon lock-in is the name for what follows.
- It cannot be revisited cheaply for the decades the plant then runs.
- Relining a blast furnace, the periodic rebuild of its inner lining, adds another fifteen to twenty years of working life and so another fifteen to twenty years of emissions.
- The cheapest mitigation in these sectors is therefore the plant not built and the rebuild not done.
- A study in Nature Climate Change found that not building new coal based blast furnaces, and not relining young ones, could almost halve the world's committed steel emissions.
What changed
Steelmaking routes
Copy link to Steelmaking routesPrelims and Mains
Which route a new plant takes is what gets locked in, because one burns coking coal by design and the other need not.
Blast furnace and basic oxygen furnace (BF-BOF)
- Blast furnace: coking coal strips oxygen from iron ore
- Basic oxygen furnace: pure oxygen refines the carbon rich iron
- 70.4% of global steelmaking
Electric arc furnace
- Melts scrap or direct reduced iron (DRI) with electricity
- Less than half the emissions intensity
- DRI made with green hydrogen and clean power: close to zero
- India has little old steel to recycle, so DRI in electric arc furnaces, not scrap, is its best option
What changed
8 Sep 2026
8 Sep 2026
- India's steel emissions run about 32 per cent above the global average.
- Steel is nearly 12 per cent of India's greenhouse gas emissions, which is why it is the test case for mitigation policy.
- More than 43 million tonnes a year of Indian capacity falls due for relining before 2030.
- India's blast furnace share is projected to reach 56 per cent by 2030, though most of those plants have not broken ground.
Methane from paddy
Copy link to Methane from paddyPrelims and Mains
Flooded paddy fields release methane because microbes in waterlogged soil break down organic matter without oxygen, which makes rice one of the largest agricultural sources of the gas and India's eastern paddy belt a global hotspot.
What changed
23 Jul 2026New subject
- A study in Nature Food finds that emissions from paddy fields worldwide have risen about 90 per cent since the 1960s, roughly half of it from loss of soil organic carbon.
- India's irrigated paddy alone releases about 3.9 million tonnes of methane a year, and paddy fields in eastern India are among the global hotspots.
- Better irrigation, fertiliser use, residue management and reduced tillage could cut rice emissions by about 10 per cent by mid century.
Mains: India has no emissions reduction target for agriculture.