Emission Inventory of Halogenated greenhouse gases in China during 1980−2050

Abstract:

China is currently the largest producer and consumer of ozone-depleting substances (ODSs) which are regulated by the Montreal Protocol (MP). Many ODSs are also powerful greenhouse gases (GHGs). The Multilateral Fund has subsidized ~1 billion US dollars for the ODS phase out in China, and thus the return on this investment is of great interest. This study gives a comprehensive emission inventory in China from 1980 to 2013 of halocarbons including ODSs and their alternatives, the hydrofluorocarbons (HFCs) that are also greenhouse gases. We then project these emissions up to 2050 according to the MP and several policy options. Total emissions of ODS and HFCs were estimated to be ~500 CO₂-eq Tg/yr in 2013 which are equivalent to ~5% of total GHG emissions in China including fossil fuel CO₂ emissions. Our estimate shows that China has succeeded in substantially reducing CFC-11-equivalent emissions (to protect the ozone layer), and CO₂-equivalent emissions (to protect climate) of ODSs since the mid-1990s when their phase out started in China in compliance with the MP. Furthermore, the avoided CO₂-eq emissions due to compliance with the MP are even greater compared to the reduced emissions, for example net cumulative avoided emissions during 19 year period between 1995–2013 are comparable to the current one year CO₂ emissions from fossil fuels in China. We find that HFC CO₂-eq emissions increased rapidly in last decade, which make up ~2% in 2005 to ~20% of total halocarbon CO₂-eq emissions in 2013. Under a baseline scenario in which HFCs are used as alternatives in the ongoing phase out of HCFCs in China, emissions of HFCs are predicted to be important components of both China’s and global future GHG emissions. However, potential exists for minimizing China’s HFC emissions under mitigation scenarios. Our conclusions about China’s past and future ODS and HFC emission trajectories are likely to apply to other developing countries, with important implications for mitigating global GHG emissions.