Dataset Information

Methane emissions from the Marcellus Shale in southwestern Pennsylvania and northern West Virginia based on airborne measurements.

ABSTRACT: Natural gas production in the U.S. has increased rapidly over the past decade, along with concerns about methane (CH₄) leakage (total fugitive emissions), and climate impacts. Quantification of CH₄ emissions from oil and natural gas (O&NG) operations is important for establishing scientifically sound, cost-effective policies for mitigating greenhouse gases. We use aircraft measurements and a mass balance approach for three flight experiments in August and September 2015 to estimate CH₄ emissions from O&NG operations in the southwestern Marcellus Shale region. We estimate the mean?±?1? CH₄ emission rate as 36.7?±?1.9?kg?CH₄?s^-1 (or 1.16?±?0.06?Tg?CH₄?yr^-1) with 59% coming from O&NG operations. We estimate the mean?±?1? CH₄ leak rate from O&NG operations as 3.9?±?0.4% with a lower limit of 1.5% and an upper limit of 6.3%. This leak rate is broadly consistent with the results from several recent top-down studies but higher than the results from a few other observational studies as well as in the U.S. Environmental Protection Agency CH₄ emission inventory. However, a substantial source of CH₄ was found to contain little ethane (C₂H₆), possibly due to coalbed CH₄ emitted either directly from coalmines or from wells drilled through coalbed layers. Although recent regulations requiring capture of gas from the completion venting step of the hydraulic fracturing appear to have reduced losses, our study suggests that for a 20?year time scale, energy derived from the combustion of natural gas extracted from this region will require further controls before it can exert a net climate benefit compared to coal.

SUBMITTER: Ren X

PROVIDER: S-EPMC5439486 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Methane emissions from the Marcellus Shale in southwestern Pennsylvania and northern West Virginia based on airborne measurements.

Ren Xinrong X Hall Dolly L DL Vinciguerra Timothy T Benish Sarah E SE Stratton Phillip R PR Ahn Doyeon D Hansford Jonathan R JR Cohen Mark D MD Sahu Sayantan S He Hao H Grimes Courtney C Salawitch Ross J RJ Ehrman Sheryl H SH Dickerson Russell R RR

Journal of geophysical research. Atmospheres : JGR 20170420 8

Natural gas production in the U.S. has increased rapidly over the past decade, along with concerns about methane (CH<sub>4</sub>) leakage (total fugitive emissions), and climate impacts. Quantification of CH<sub>4</sub> emissions from oil and natural gas (O&NG) operations is important for establishing scientifically sound, cost-effective policies for mitigating greenhouse gases. We use aircraft measurements and a mass balance approach for three flight experiments in August and September 2015 to ...[more]

PMID: 28603681

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Dataset Information

Methane emissions from the Marcellus Shale in southwestern Pennsylvania and northern West Virginia based on airborne measurements.

Publications

Methane emissions from the Marcellus Shale in southwestern Pennsylvania and northern West Virginia based on airborne measurements.

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