A global gridded (0.1° × 0.1°) inventory of methane emissions from oil, gas, and coal exploitation based on national reports to the United Nations Framework Convention on Climate Change

Abstract

Abstract. Individual countries report national emissions of methane, a potent greenhouse gas, in accordance with the United Nations Framework Convention on Climate Change (UNFCCC). We present a global inventory of methane emissions from oil, gas, and coal exploitation that spatially allocates the national emissions reported to the UNFCCC (Scarpelli et al., 2019). Our inventory is at 0.1∘×0.1∘ resolution and resolves the subsectors of oil and gas exploitation, from upstream to downstream, and the different emission processes (leakage, venting, flaring). Global emissions for 2016 are 41.5 Tg a−1 for oil, 24.4 Tg a−1 for gas, and 31.3 Tg a−1 for coal. An array of databases is used to spatially allocate national emissions to infrastructure, including wells, pipelines, oil refineries, gas processing plants, gas compressor stations, gas storage facilities, and coal mines. Gridded error estimates are provided in normal and lognormal forms based on emission factor uncertainties from the IPCC. Our inventory shows large differences with the EDGAR v4.3.2 global gridded inventory both at the national scale and in finer-scale spatial allocation. It shows good agreement with the gridded version of the United Kingdom's National Atmospheric Emissions Inventory (NAEI). There are significant errors on the 0.1∘×0.1∘ grid associated with the location and magnitude of large point sources, but these are smoothed out when averaging the inventory over a coarser grid. Use of our inventory as prior estimate in inverse analyses of atmospheric methane observations allows investigation of individual subsector contributions and can serve policy needs by evaluating the national emissions totals reported to the UNFCCC. Gridded data sets can be accessed at https://doi.org/10.7910/DVN/HH4EUM (Scarpelli et al., 2019).

Attribution of the accelerating increase in atmospheric methane during 2010–2018 by inverse analysis of GOSAT observations

“…We supersede it for the US with the gridded version of the Environmental Protection Agency inventory for 2012 (Maasakkers et al, 2016). We further supersede it globally for fuel (oil, gas, and coal) exploitation with the inventory of Scarpelli et al (2020) for 2012, which disaggregates spatially the national emissions reported to the United Nations Framework Convention on Climate Change (UNFCCC) (di.unfccc.int). All anthropogenic emissions are assumed to be aseasonal, except manure management for which we apply local temperature-dependent corrections (Maasakkers et al, 2016), and rice cultivation for which we apply gridded seasonal scaling factors from B.…”

“…This finding is consistent with Maasakkers et al 2019 the UNFCCC, and our posterior estimate of total anthropogenic emissions is closer to the country's latest submission to UNFCCC for 2010-2018 (16 Tg a -1 ; Figure 6). The new submission revises oil/gas methane emissions downward by a factor of 3 relative to the previous submission used as prior estimate in our inversion (Scarpelli et al, 2020).…”

“…(2) correction of stratospheric methane forward model biases based on ACE-FTS solar occultation satellite data (Waymark et al, 2014); (3) prior estimates of global fuel exploitation emissions using national reports submitted to the United Nations Framework Convention on Climate Change (UNFCCC) (Scarpelli et al, 2020), and (4) optimization of annual hemispheric OH concentrations.…”

Global methane budget and trend, 2010–2017: complementarity of inverse analyses using in situ (GLOBALVIEWplus CH<sub>4</sub> ObsPack) and satellite (GOSAT) observations

“…Natural sources include the ensemble mean of the WetCHARTS inventory version 1.2.1 (Bloom et al, 2017) for wetlands, open fires from the Global Fire Emissions Database version 4s with seasonal and interannual variability (van der Werf et al, 2017), termites from Fung et al (1991), and seeps from Etiope et al (2019) with global scaling to 2 Tg a -1 from Hmiel et al (2020). The default anthropogenic emissions are from EDGAR v4.3.2 (Janssens-Maenhout et al, 2019), and are superseded for fugitive fuel emissions (oil, gas, coal) by the Scarpelli et al (2020) inventory which spatially allocates national emissions reported by countries to the United Nations Framework Convention of Climate Change (UNFCCC). US anthropogenic emissions are further superseded by the gridded version of Inventory of U.S. Greenhouse Gas Emissions and Sinks from the Environmental Protection Agency (EPA GHGI) (Maasakkers et al, 2016).…”

Estimating CH<sub>4</sub>, CO<sub>2</sub>, and CO emissions from coal mining and industrial activities in the Upper Silesian Coal Basin using an aircraft-based mass balance approach

“…Scarpelli et al (2020) published the newest gridded emission inventory available for comparison within in this study. It only contains CH 4 emissions from oil, natural gas and coal exploitation.…”