Abstract: The status, trends and key sources of CH₄ emissions in Annex I countries are explored, based on GHGs emissions data from Parties submitted by Annex I countries to the United Nations Framework Convention on Climate Change (UNFCCC) from 1990 to the most recent inventory year (2020). The results show that: (1) In 2020, the total CH₄ emissions of the 42 countries in Annex I of the UNFCCC were 187,223.1 kt CO_?-eq, and the combined CH4 emissions of the United States, the Russian Federation and Australia accounted for 60% of the total emissions. (2) Compared with 1990, the overall CH₄ emissions of Annex I countries/groups of UNFCCC showed a downward trend in 2020, of which United States, the Russian Federation, Australia, the European Union (Convention) and the European Union (Kyoto Protocol) decreased by 14.79%, 29.69%, 24.01%, 40.56% and 40.34% respectively, while Turkey, Spain, New Zealand and Ireland increased by 50.62%, 2.49%, 3.97% and 7.91% respectively. (3) CH₄ emissions in major developed countries mainly come from the agricultural and energy sectors, followed by the waste sector. Among them, in the agricultural sector mainly from enteric fermentation, followed by manure management; CH₄ emissions from the energy sector come mainly from escape emissions from fuels; The main source of emissions in the waste sector is solid waste landfills.

Key words: UNFCCC, GHGs, CH4, Emission characteristics