Co-benefits of low carbon pathways for local air pollution in India

Paris Climate Change Agreement requires countries to determine and implement their climate action mitigation and adaptation targets under Nationally Determined Contributions (NDC) in order to achieve the target of well below 2⁰C. Additionally, India needs to meet its sustainable development goals (SDGs) by 2030.

Studies have recognized co-benefits from decarbonization pathways to reduce air pollution and improve local environment benefits in specific sectors. In this study, we integrate bottom up analysis from Asia-Pacific Integrated Assessment Model (AIM/E-India), a national energy systems model, with Greenhouse Gas and Air Pollution Interactions and Synergies model (GAINS) to assess the benefits of air quality improvement, and health impacts under national policies implemented (NPi), NDC, 2 °C and the well below 2 °C scenarios for India.

Sulphur dioxide (SO₂) emissions in 2015 were estimated highest in power and industry sector. Initial results show significant decrease in SO₂ levels across decarbonization scenarios in power sector. Transport sector has highest nitrogen oxides (NOx) levels in 2015 in NPi scenario. Due to improved pollution and vehicular technology standards, there is considerable decrease in NOx emissions across low-carbon scenarios. Building sector followed agriculture and power sector are responsible for majority of PM_2.5 emissions. A combination of shift to cleaner fuels and efficient technologies reduce PM_2.5 emissions across all scenarios.

Consequently, by 2030, approximately 69 % - 84% of people are exposed to concentrations less than 50 μg/m³, as compared to 65% in 2015 (Figure 1). A significant decrease in premature deaths is projected in all scenarios in 2050 over NPi.

The results show impact of climate and development policies on air quality and health in short, medium and long terms. We conclude that without additional measures, the current policies will not be adequate to avoid the surge in SO₂, NOx and PM_2.5 emissions after 2030.