Reducing Non-CO₂ Climate Pollutants

Methane and fluorinated gasses, as well as anthropogenic black carbon, are short-lived climate pollutants (SLCP) that have relatively short atmospheric lifetimes but trap heat more efficiently than CO₂ on a per-unit basis making them potent climate forcers with the potential to significantly warm the atmosphere and ocean. SLCPs have exacerbated other climate change-related impacts – including disrupting seasonal rain patterns, accelerating Arctic melting, and contributing to deadly air pollution. The Intergovernmental Panel on Climate Change has recognized that reducing SLCPs is crucial to limit global temperature rise to below 1.5°C.

Combined, black carbon from fossil-fuel combustion; methane from agriculture and fossil fuel operations; hydrofluorocarbons (HFCs) from cooling, refrigeration and other industrial uses; and tropospheric ozone formed from air pollutants are responsible for up to 45% of current global warming. In addition, the longer-lived nitrous oxide (N₂O), is a potent GHG and ozone depleting substance that contributes the equivalent of about 10% of today’s CO₂ warming.

Researchers at the International Energy Analysis Department have conducted research in the following areas to understand non-CO₂ and SLCP mitigation potential and support mitigation actions. 

Non-CO₂ Greenhouse Gas (GHG) Mitigation Scenario Analysis

ETA’s international analysis researchers and collaborators have established a novel bottom-up, end-use modeling framework to project future national non-CO₂ GHGs emissions, including methane, N₂O, and F-gasses. This modeling framework provides an understanding of the sources and drivers for future non-CO₂ GHG emissions, and various technological and policy options for specifically addressing these gasses. It has been applied to China to evaluate different scenarios of non-CO₂ GHG emission trajectories, based on different adoption of mitigation technologies and measures based on technological feasibility and costs of abatement. The different mitigation scenarios will present policymakers and program implementers with tools and insights to set realistic and achievable near-term and long-term goals and prioritize and initiate actions quickly to combat climate change. 

Techno-economic and Cost-curve Analysis of Mitigation Options

Based on ongoing collaboration, ETA’s international analysis researchers have conducted deep techno-economic analysis of non-CO₂ GHG mitigation measures and evaluated the cost-effectiveness of these measures in a country-specific context. The mitigation cost-curves developed based on this research and collaboration help shed light on the potential paces of mitigation by gas and by sector given technical and economic constraints.  

Policy Analysis

ETA’s international analysis researchers have analyzed and reviewed international policies, targets, and best practices for mitigating non-CO₂ GHG emissions at national, subnational and sectoral levels. We are also actively engaging with global policymakers and stakeholders and conducting other outreach activities to share and publicize our research results to help facilitate the development and implementation of SLCP policies.

Publications

Lin, Jiang, Nina Khanna, Xu Liu, Wenjun Wang, Jennifer Gordan, Fan Dai. 2021. “Opportunities to Tackle Short-lived Climate Pollutants and Other Greenhouse Gases for China.”  CCCI report. https://ccci.berkeley.edu/sites/default/files/Opportunities-to-Tackle-SLCPs-for-China.pdf

Lin, Jiang, Nina Khanna, Xu Liu, Fei Teng, and Xin Wang. "China’s Non-CO₂ Greenhouse Gas Emissions: Future Trajectories and Mitigation Options and Potential." Scientific Reports 9.1 (2019).

Wang, Xin, Fei Teng, Jingjing Zhang, Nina Khanna, and Jiang Lin. "Challenges to addressing non-CO₂ greenhouse gases in China’s long-term climate strategy." Climate Policy 18.8 (2018) 1059 - 1065.