This dataset was used in the generation of the manuscript titled: Implied climate warming contributions of enteric methane emissions are dependent on the estimate source and accounting methodology (DOI: 10.15232/aas.2022-02344). The objectives of this manuscript were to (1) demonstrate the differences in enteric methane emission estimates between 2 reporting entities (FAO and EPA) and to (2) demonstrate how the implied contribution to climate warming caused by enteric methane is dependent on accounting methodologies. The accounting methodologies explored were the conventional global warming potential (GWP) based on a 100-year time horizon (GWP100) or the newer GWP. The GWP methodology was developed because GWP100 fails to capture the short atmospheric lifespan of CH4, which is only 12-years (EPA, 2021a). The equations to calculate GWP100 (Equation 1; IPCC, 2013) and GWP* (Equation 2; Smith et al., 2021) are:
CH4, Mt CO2 equivalence = 28 × CH4(t) [Equation 1];
CH4, Mt CO2-we = (4.53 × CH4(t) – 4.25 × CH4(t–20)) × 28 [Equation 2].
Where CH4(t) is the CH4 emitted in million metric tons (Mt) at year t and CH4(t-20) is the amount of CH4 emitted in Mt 20-years prior.
Data was obtained from publicly available sources — the USDA-NASS biannual reports on cow and calf inventory in January and June (USDA-NASS, 2022), the EPA website (EPA, 2021b), and FAO from the FAOSTAT website (FAO, 2022). The data provided herein is an excel spreadsheet (.xlsx format) and contains 5 different sheets. Sheet titled "Descriptions" describe what each column names contain for the data-containing sheets.
References:
EPA (US Environmental Protection Agency). 2021a. Inventory of US Greenhouse Gas Emissions and Sinks 1990–2019. US Environmental Protection Agency.
EPA (US Environmental Protection Agency). 2021b. Inventory of US Greenhouse Gas Emissions and Sinks: 1990–2019. Accessed May 18, 2022. https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-a....
FAO (Food and Agriculture Organization). 2022. FAOSTAT Emissions Totals. Accessed: May 18, 2022. https://www.fao.org/faostat/en/#data/GT.
IPCC (Intergovernmental Panel on Climate Change). 2013. Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. T. F. Stocker, D. Qin, G. K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex, and P. M. Midgley, ed. Cambridge University Press.
NASS (National Agricultural Statistics Service). 2022. Cattle NASS. Accessed May 18, 2022. https://usda.library.cornell.edu/concern/publications/h702q636h?locale=en.
Smith, M. A., M. Cain, and M. R. Allen. 2021. Further improvement of warming-equivalent emissions calculation. npj Clim. Atmos. Sci. 4:1–3. https://doi.org/10.1038/s41612-021-00169-8.