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 disaggregates the national emissions reported to the UNFCCC. 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. 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.

High-frequency monitoring of anomalous methane point sources with multispectral Sentinel-2 satellite observations

“…Assuming a 93 % persistence rate and no diurnal variability, the average of our two estimates of the mean source rate implies total methane emissions of 66 Gg over the course of the 10-month-long emission event. This represents 6 % of the annual national methane emission of 1.19 Tg from the oil and gas sector reported by the Algerian government to the United Nations Framework Convention on Climate Change (UNFCCC; Scarpelli et al, 2020b). Given the facility operators' ultimate intervention by flaring in August 2020, it would appear that a large proportion of these emissions could have been avoided had the operators been alerted soon after the emissions began.…”

“…Using the full-record 40 % persistence rate and assuming no diurnal variability in emissions, we estimate total methane emissions of 373 Gg from the compressor station between 29 August 2015 and 26 October 2020, or about 75 Gg yr −1 . This represents 5 % of the annual national methane emission of 1.4 Tg from the oil and gas sector reported by the Turkmen government to the United Nations Framework Convention on Climate Change (UNFCCC; Scarpelli et al, 2020b). Varon et al (2019) previously estimated emissions from the Korpezhe point source using GHGSat-D observations from February 2018 to January 2019.…”

Satellite Discovery of Anomalously Large Methane Point Sources From Oil/Gas Production

“…Methane emissions inventory data and surface imagery for the GHGSat scene. (a) Methane emissions from oil/gas production, refining, processing, transport, and storage across Turkmenistan, as estimated from a global inventory with 0.1°× 0.1°grid resolution byScarpelli et al (2019). The thick line shows the boundaries of Turkmenistan.…”

Comparison between developed inventory and EDGAR database

“…Attached, you can find a summary of the sources for the activity data, emission factors and methods for spatial disaggregation of emissions associated with the different IPCC sub-categories for CH4 fugitive emissions. Further details can be found in Janssens- Maenhout et al (2019 ) and Crippa et al (2019). This may help the authors understand the differences between the approaches used in our database for the emission quantification, the methodology presented in the manuscript and national submissions to UNFCCC.…”