Modeling China’s Non-CO2 Greenhouse Gas Emissions: Future Trajectories and Mitigation Options and Potential
While China’s role as the world’s largest consumer of energy and emitter of energy-related carbon dioxide (CO2) is now well known, China’s role as the world’s largest non-CO2 greenhouse gas (GHG) emitter is less recognized. According to China’s last official Second National Greenhouse Gas Inventory of 2005, non-CO2 GHGs contributed 20% of total national GHGs, accounting for 1.49 gigatons (Gt) of CO2-equivalent (Figure 1). These key non-CO2 greenhouse gases include methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6) and nitrogen trifluroide (NF3).
China’s non-CO2 GHGs are expected to grow due to changes in consumer preferences and behaviors and subsequent impacts on the agricultural sector, increased urbanization and waste generation, and continued demand for coal mining and industrial production that emits non-CO2 GHGs. A recent comparative analysis by the World Resources Institute (WRI) of projections from three recent research studies by the Chinese and U.S. environmental agencies and Peking University suggests that China’s non-CO2 GHGs could double from 2005 levels by 2030 (Bo et al., 2016). However, there is a significant mitigation potential for reducing non-CO2 GHGs–-the WRI study found about a 30% reduction potential of projected non-CO2 GHGs in 2030. If shorter time-horizons are considered using 20-year GWP instead of 100-year GWP to assess all GHGs, then non-CO2 GHGs’ share of China’s total GHG mitigation potential in 2030 increases from 17% to 27%. This suggests that in the short-term, non-CO2 mitigation will be crucial to China’s overall GHG reduction.
It is critical for China to have a clear understanding of the drivers for non-CO2 GHGs and the potential for reducing this overall growth in both energy and non-energy related non-CO2 GHGs in order to establish effective policies and programs that address all GHGs and enable realization of the overall Paris Agreement goal of “holding the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels” (U.N., 2016).
This research will be conducted by Berkeley Lab's China Energy Group in collaboration with other experts at Berkeley Lab, UC Berkeley, Tsinghua University, and other leading universities and research institutes in China. This research will be the first joint collaborative project under the newly launched Berkeley-Tsinghua Joint Research Center on Energy and Climate Change.
Lin, Jiang, Nina Khanna, and Xu Liu. China's Non-CO2 Greenhouse Gas Emissions: Future Trajectories, and Mitigation Options and Potential. BTJRC Working Paper 003. August 2018.