Indias critical efforts to tackle air pollution could worsen warming, Pg 20

• Rapidly reducing aerosol emissions (which cool the atmosphere by reflecting sunlight) could lead to sudden warming if greenhouse gases (GHGs) are not reduced simultaneously.

• Aerosols mask the warming effect of GHGs; removing them reveals latent temperature rise, especially in highly polluted regions like India.

• Study in Geophysical Research Letters shows areas that cleaned their air in the late 20th century saw faster warming.

• Urban areas with high pollution and low development indices showed lower warmingdue to pollution masking effect.

• Indias Indo-Gangetic plains are particularly vulnerable due to high aerosol loading and dense population.

• GHGs (e.g., CO2, methane) trap heat and cause long-term warming.

• Aerosols (e.g., sulphates, nitrates) reflect sunlight and cool the earth temporarily, also impacting rainfall patterns.

• Removing aerosols without cutting GHGs can cause abrupt warming and erratic monsoons.

• Indias warming offset by aerosols: without them, warming could have been 0.13C higher.

• Net-zero emissions alone wont ensure safety unless adaptation measures are taken.

• Policymakers must focus on vulnerable regions like Indo-Gangetic plains.

• Long-term plans needed to support at-risk populations, especially if warming suddenly intensifies post aerosol removal.

• Delhi-based Urban Collaborative study shows that top polluted cities like Delhi, Mumbai, Lucknow, etc., may face sudden rise in temperature if aerosols are removed.

• India's energy sources (70% electricity from coal) add to the sulphur dioxide-based aerosol load.

• Policy must balance air quality goals with climate adaptation needs.

• India needs region-specific modelling to understand warming outcomes post aerosol reduction.

Mains Mock Question:

"India's efforts to reduce air pollution, though crucial for public health, may paradoxically intensify warming in the short term. Examine this paradox and suggest a balanced way forward for Indias climate and public health policy."