Methane Surface Emissions from Natural Sources

The Methane Surface Emissions from Natural Sources is based on the following open-access datasets: Sector Magnitude[Tg(CH4) yr-1] resolution frequency temporal extent Reference global wetlands 161.1 0.5°x0.5° monthly 2001-01-01 to 2022-08-31 Bloom et al., 2021 lakes 40.9 0.25°x0.25° daily 2012-01-01 to 2012-12-31 Johnson et al., 2022 reservoirs 9.9 0.25°x0.25° daily 2002-01-01 to 2015-12-31 Johnson et al., 2021 geological, on-shore 37.0 1°x1° monthly average PD degassinglong-term variability information unavailable Etiope et al., 2019 geological, off-shore 9.2 0.25°x0.25° monthly 1985-2016 climatology valid at PI, PD & FU Weber et al., 2019 termites 19.7 0.5°x0.5° monthly 2000-2017(later revisions potentially available) CAMS_81 – D81.3.4.1 Gridded CH4 emissions from termites From these datsets a methane emission inventory for natural sources has been produced in WP4/5 of the European Commission funded ESM2025 Project. This inventory consists of global gridded (1°x1° horizontal resolution) decadal average monthly mean methane emissions centred on the year 2012 for lakes, 2008 for reservoirs and 2010 for all other. The dataset includes emissions from 5 sectors: lakes, reservoirs, offshore- and onshore geological and termites. 2010 is adopted as the anchor year for all sectors in the inventory. The resulting monthly mean methane 2010 time slice emission inventory consists of these sectors: Sector (Anchor-) Year Magnitude (Tg(CH4)/yr) Frequency Resolution Global wetlands 2010 161.1 monthly 1°x1° Lakes 2010 40.9 monthly 1°x1° Reservoirs 2010 9.9 monthly 1°x1° Offshore Geological 2010 9.2 monthly 1°x1° Onshore Geological 2010 37.0 monthly 1°x1° Termites 2010 19.7 monthly 1°x1° Note: The offshore geological sector has negative emissions in the raw data. These negative values in the dataset have not been removed in this inventory to stay as close as possible to the original datsets.