Pollution, Climate Change and International Conventions

Climate change in brief

• Greenhouse gases (GHGs): carbon dioxide, methane, nitrous oxide, ozone, water vapour and fluorinated gases (e.g. HFCs). They trap heat, which causes global warming.
• Effects: melting glaciers, sea-level rise, extreme heat, erratic monsoons, coral bleaching, and threats to farming and health.
• Mitigation = reduce emissions (renewables, efficiency, forests). Adaptation = adjust to impacts (heat action plans, drought-resistant crops).

Key international agreements

Principle of CBDR-RC – common but differentiated responsibilities and respective capabilities: developed countries should lead.

Indian environmental laws and bodies

• Water Act 1974, Air Act 1981, Forest (Conservation) Act 1980, Environment (Protection) Act 1986 (passed after the Bhopal gas tragedy), Biological Diversity Act 2002.
• Central Pollution Control Board; the National Green Tribunal (2010).
• National Action Plan on Climate Change (2008) with 8 national missions (e.g. the Solar Mission).
• International Solar Alliance – launched by India and France at the 2015 Paris COP.

Pollution quick facts

• PM2.5 – fine particles that reach deep into the lungs; a major cause of urban air-quality problems.
• Eutrophication – excess nutrients (fertilisers) cause algal blooms, which use up oxygen in water.
• Ozone: good in the stratosphere, harmful at ground level (a component of smog).

Background: pollution in four forms

The Environment (Protection) Act 1986 – an umbrella law passed after the Bhopal gas tragedy (1984). The National Green Tribunal (2010) provides quick environmental justice. Judicial principles: polluter pays, the precautionary principle, and the public trust doctrine (M.C. Mehta cases).

Climate change – the science made simple

• Greenhouse gases (CO₂, methane, nitrous oxide, F-gases) trap heat.
• CO₂ concentration has risen from about 280 ppm before industrialisation to above 420 ppm now.
• The IPCC AR6 (2021–23) says human influence has unequivocally warmed the planet – about 1.1°C above pre-industrial levels (2011–20) – and global warming is likely to reach 1.5°C in the early 2030s.
• 2024 was the first calendar year above 1.5°C (WMO), though the Paris goal refers to long-term averages.

Effects on India:

• heatwaves;
• erratic monsoon and extreme rainfall;
• glacier melt (risk of GLOFs – the Sikkim South Lhonak lake flood of 2023);
• sea-level rise (Mumbai, Sundarbans);
• cyclones intensifying in the Arabian Sea;
• falling crop yields;
• vector-borne diseases.

The international regime – timeline

Key principle: Common But Differentiated Responsibilities and Respective Capabilities (CBDR-RC) – rich countries caused most historical emissions, so they must lead and pay.

Biodiversity treaties:

• CBD with the Cartagena (biosafety) and Nagoya (access and benefit-sharing) Protocols;
• the Kunming-Montreal Global Biodiversity Framework (2022) – 30x30;
• CITES (wildlife trade);
• CMS (migratory species);
• the Ramsar Convention (1971, wetlands).

India's climate action

Updated NDC (2022):

• reduce the emissions intensity of GDP by 45% by 2030 from 2005 levels;
• 50% of installed power capacity from non-fossil sources by 2030 – achieved in 2025, ahead of schedule;
• an additional carbon sink of 2.5–3 billion tonnes of CO₂-equivalent through forests.

Other actions:

• the NAPCC (2008), with eight missions (solar, efficiency, habitat, water, Himalaya, Green India, agriculture, knowledge) and state action plans;
• Mission LiFE (Lifestyle for Environment);
• the Green Credit Programme (2023);
• the Carbon Credit Trading Scheme (2023);
• the International Solar Alliance;
• the CDRI.

Case study: the Montreal Protocol – how global cooperation can work

In the 1980s, scientists discovered the Antarctic ozone hole, caused by CFCs. Within two years, countries signed the Montreal Protocol. It succeeded because of:

• clear science;
• available substitutes;
• a Multilateral Fund to help developing countries;
• trade measures against non-parties.

The ozone layer is projected to recover to 1980 levels around the middle of this century. The Kigali Amendment now targets HFCs, which are potent greenhouse gases – it could avoid up to about 0.4°C of warming by 2100. Lesson: science + finance + equity + flexibility = a successful treaty.

Common misconceptions

• "India is among the biggest historical polluters." – India is the third-largest annual emitter today, but its per-capita emissions are far below the world average, and its cumulative historical emissions are small (about 3–4%).
• "Net zero means zero emissions." – It means remaining emissions are balanced by removals (forests, carbon capture).
• "The ozone hole and global warming are the same issue." – They are linked only partly (some gases do both).

How UPSC asks it

Prelims frequently asks about convention features and years, the bodies under them, and Indian targets and missions. Mains themes include climate justice and CBDR, India's energy transition, air pollution in north India, the loss and damage fund, and carbon markets.

Mains answer framework

Q-type: "Discuss India's climate commitments and the challenges in achieving them."

• Intro: Paris, the 2022 NDC, net zero 2070.
• Commitments and progress: renewable capacity, emissions intensity, the green hydrogen mission, carbon markets.
• Challenges: coal dependence, storage, finance and technology, the just transition for coal regions (Jharkhand), adaptation needs.
• Way forward: a grid and storage push, climate finance mobilisation (green bonds), adaptation in agriculture, LiFE behaviour change, international cooperation.
• Conclusion: development and decarbonisation as twin goals.

India's climate commitments (updated NDC, 2022)

• Reduce the emissions intensity of GDP by 45% from the 2005 level by 2030.
• About 50% of cumulative electric power capacity from non-fossil sources by 2030.
• An additional carbon sink of 2.5–3 billion tonnes of CO₂ equivalent through forest and tree cover by 2030.
• Net-zero emissions by 2070 (announced at COP26, Glasgow).