India’s Air Pollution Dilemma: Balancing Clean Air and Climate Goals

This article from The Hindu, dated April 2, 2025, delves into the complex interplay between India’s efforts to combat air pollution and the unintended consequences of exacerbating global warming. It highlights scientific findings and policy challenges, offering critical insights into environmental governance, public health, and climate change mitigation strategies relevant for understanding India’s developmental and ecological priorities.

Key Points

• Study Warning: A recent study cautions that rapidly reducing aerosol emissions without cutting greenhouse gases could expose vulnerable populations to extreme heat, intensifying warming.
• Dual Challenge: India faces the twin challenge of improving air quality while mitigating climate change, a balancing act complicated by its reliance on coal-based power.
• Thermal Power Contribution: Approximately 70% of India’s electricity comes from coal-fired thermal power plants, which emit sulphur that forms reflective sulphate aerosols.
• Aerosols’ Cooling Effect: Aerosols like sulphates and nitrates scatter solar radiation, cooling the Earth’s surface and partially offsetting greenhouse gas-induced warming.
• Greenhouse Gases vs. Aerosols: While greenhouse gases trap heat, causing temperature and rainfall extremes, aerosols mitigate this to some extent by reflecting sunlight.
• Warming Risk: Abruptly halting aerosol emissions could accelerate short-term warming, as noted by Aditya Sengupta, a researcher at the University of Melbourne.
• Sulphur Dioxide Control: To reduce air pollution, sulphur dioxide is removed from coal plant exhaust (flue gas), decreasing sulphate aerosol levels, which constitute 50-60% of India’s aerosol mix.
• Aerosol Composition: Besides sulphates, India’s aerosols include black carbon, dust, and other pollutants, influencing both climate and air quality.
• Warming Estimates: Without aerosols, India would experience significantly greater warming, according to Krishna AchutaRao, a professor at IIT-Delhi.
• Historical Temperature Rise: India’s average temperature increased by 0.7°C from 1901 to 2018, per a 2020 Ministry of Earth Sciences report, driven by greenhouse gases but moderated by aerosols and land-use changes.
• Global Comparison: Global warming stands at 1.3°C above pre-industrial levels, with aerosols providing a cooling effect of about 0.6°C globally (0.9°C in the Northern Hemisphere, 0.3°C in the Southern Hemisphere), per an IPCC report.
• Precipitation Complexity: Removing aerosols straightforwardly increases temperatures, but their impact on rainfall is less predictable and more complex.
• Industrial Link: Economic growth and industrialization in India are tied to both aerosol and fossil fuel emissions, complicating emission reduction strategies.
• Policy Implications: Effective air pollution control requires integrating greenhouse gas reductions to avoid unintended warming, a critical consideration for India’s environmental policies.

Glossary

• Aerosols: Tiny particles in the air that scatter sunlight, providing a cooling effect.
• Greenhouse Gases: Gases like CO2 that trap heat in the atmosphere, driving global warming.
• Sulphate Aerosols: Reflective particles formed from sulphur dioxide, counteracting some warming.
• Thermal Power Plants: Coal-based facilities generating electricity and emitting pollutants.
• Sulphur Dioxide: A gas from coal combustion, controlled to reduce air pollution.
• Black Carbon: A pollutant from incomplete combustion, contributing to warming and air quality issues.
• Global Warming: The rise in Earth’s average temperature due to human-induced emissions.
• IPCC: Intergovernmental Panel on Climate Change, a global body assessing climate science.
• Flue Gas: Exhaust from coal combustion, treated to remove pollutants like sulphur dioxide.
• Climate Mitigation: Actions to reduce or offset the impacts of climate change.

Link To The Original Article – https://www.thehindu.com/sci-tech/energy-and-environment/india-vital-efforts-tackle-air-pollution-worsen-warming/article69403439.ece