Anthropogenic CH4 Emissions over China in 2022 Inverted Using TROPOMI XCH4 Retrievals

We developed the Regional Methane Assimilation System (RegGCAS-CH₄) based on the WRF-CMAQ model and the EnKF algorithm. By assimilating extensive TROPOMI column-averaged dry CH₄ mixing ratio (XCH₄) retrievals, we conducted high-resolution nested inversions to quantify daily CH₄ emissions across China and Shanxi Province in 2022. Nationally, posterior anthropogenic CH₄ emissions were 45.1 TgCH₄·yr⁻¹, 36.5% lower than the EDGAR estimates, with the largest reductions in the coal and waste sectors. 

XCH4_2022_China.nc and XCH4_2022_Shanxi.nc contain prior and posterior XCH₄ simulations, as well as TROPOMI XCH₄ observations over China and Shanxi Province.
SURFCH4_2022_China.nc and SURFCH4_2022_Shanxi.nc contain prior and posterior concentration simulations of surface-level CH₄ over China and Shanxi Province.
RegGCAS_CH4EMIS_2022_China.nc and RegGCAS_CH4EMIS_2022_Shanxi.nc contain the inverted daily anthropogenic CH₄ emissions over China and Shanxi Province, respectively.
EDGAR_CH4EMIS_2022_China.nc and EDGAR_CH4EMIS_2022_Shanxi.nc contain the monthly anthropogenic CH₄ emissions over China and Shanxi Province from EDGAR, respectively.
obspack.zip contains CH₄ concentration data from five in-situ and five flask monitoring sites.