1. Understanding Air Pollution and Aerosols

• Aerosols are tiny particles suspended in the air that originate from both natural and anthropogenic (human-induced) sources.
• They include sulphates, nitrates, black carbon, and dust particles, and can reflect sunlight, thereby exerting a cooling effect on Earth’s climate.
• Despite reducing visibility and harming health, aerosols mask the actual warming impact of greenhouse gases by reflecting sunlight.

2. The Climate-Aerosol Paradox

• Reducing aerosols helps clean the air, improving public health.
• However, it can expose the hidden warming effect previously masked by aerosol cooling.
• Regions with successful air pollution control measures in the late 20th century have experienced faster temperature increases, e.g. parts of Europe and North America.
• In contrast, low Human Development Index (HDI) regions, including parts of India, have seen lower warming trends due to higher aerosol loads.

3. Impact on India

• India’s air pollution is dominated by sulphate aerosols from coal-burning power plants and other fossil fuels.
• Thermal power plants produce 70% of India’s electricity and release large amounts of sulphur dioxide, which forms sulphate aerosols.
• Highly reflective sulphate aerosols make up 50-60% of India’s aerosol load, leading to an invisible offset of warming.
• Reduction in sulphur emissions may increase local warming and further accelerate glacial melt, water stress, and heatwaves.

4. Health and Environmental Concerns

• Aerosols cause respiratory illnesses, cardiovascular diseases, and premature deaths.
• They also damage crops and ecosystems, affect monsoons, and degrade visibility.
• Hence, reducing them is a public health imperative.

5. Global Perspective and Research Insights

• According to a study by Aditya Sagnik and researchers at Monash University and IIT Bombay:
  • The cooling effect of aerosols may have masked nearly 0.5°C to 1°C of global warming.
  • Achieving air quality goals could unmask this latent warming, contributing to further climate risks.
• IPCC reports and other global models have acknowledged this trade-off.

6. India’s Air Pollution Control Measures

• India has launched several key initiatives:
  • National Clean Air Programme (NCAP) aims to reduce particulate matter (PM2.5 and PM10) by 20-30% in non-attainment cities by 2024.
  • Faster Adoption and Manufacturing of Hybrid and Electric Vehicles (FAME) scheme to reduce vehicular emissions.
  • Promotion of LPG and clean cooking fuels under the Ujjwala Yojana.
  • Switching to BS-VI emission standards in vehicles.
  • Initiatives to control stubble burning, e.g. bio-decomposer sprays in Punjab, Haryana, and Delhi.
  • Commission for Air Quality Management (CAQM) established to coordinate efforts in NCR.

7. Way Forward and Policy Recommendations

• Integrated policy design is required—air pollution reduction must go hand-in-hand with GHG mitigation.
• Future policies must:
  • Balance aerosol reduction with climate goals.
  • Promote cleaner energy transitions, including renewables and hydrogen.
  • Include agriculture, industry, and transport sectors in air quality planning.
  • Ensure public participation and scientific awareness.
  • Include co-benefit planning—tackling air pollution, climate change, and public health together.

8. Key Challenges

• Lack of real-time data and ground-level enforcement.
• Fragmented jurisdiction between central, state, and local bodies.
• Insufficient focus on rural air pollution sources.
• Resistance from industries and economic concerns over energy transition.

Conclusion

India’s fight against air pollution is a complex balancing act between public health, energy needs, and climate commitments. While reducing aerosols will save lives, unmasking hidden warming requires synchronized action on climate adaptation, renewable energy, and long-term planning. It is not just an air quality issue, but a multi-sectoral challenge with national and global implications.