Relation of air pollution and climate change

Air pollution is the presence of harmful gases and particles in the atmosphere; climate change is the long-term change in global temperature and weather patterns, mainly due to greenhouse gases from human activities. The two are closely related because they mostly share the same sources – burning of fossil fuels and biomass.

How air pollution causes climate change

1. Greenhouse gases – CO₂ from vehicles, industries and power plants, CH₄ from agriculture and waste, N₂O from fertilisers, and CFCs trap outgoing heat and warm the Earth.
2. Short-lived climate pollutants – black carbon (soot from diesel engines, brick kilns, cook stoves) absorbs sunlight and warms the air; deposited on Himalayan snow and glaciers it darkens the surface and speeds melting. Ground-level ozone is also a greenhouse gas.
3. Aerosols – sulphate particles reflect sunlight and cause local cooling, and change cloud and monsoon patterns.

How climate change worsens air pollution

1. Higher temperatures speed the formation of ground-level ozone and smog.
2. More droughts and heat increase forest fires, adding smoke (as seen in Nepal in spring).
3. Changes in wind and rain patterns can trap pollutants longer.
4. More pollen and dust in a warmer, drier climate.

Common solutions (co-benefits)

• Replace fossil fuels with hydropower, solar and wind.
• Electric vehicles and public transport.
• Clean cooking (electric, biogas) instead of firewood.
• Cleaner brick kilns and industries.
• Forest protection and tree planting.

Cutting air pollution therefore improves public health immediately and slows climate change at the same time.