Dataset Information

Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region.

ABSTRACT: Methane (CH4) impacts climate as the second strongest anthropogenic greenhouse gas and air quality by influencing tropospheric ozone levels. Space-based observations have identified the Four Corners region in the Southwest United States as an area of large CH4 enhancements. We conducted an airborne campaign in Four Corners during April 2015 with the next-generation Airborne Visible/Infrared Imaging Spectrometer (near-infrared) and Hyperspectral Thermal Emission Spectrometer (thermal infrared) imaging spectrometers to better understand the source of methane by measuring methane plumes at 1- to 3-m spatial resolution. Our analysis detected more than 250 individual methane plumes from fossil fuel harvesting, processing, and distributing infrastructures, spanning an emission range from the detection limit [Formula: see text] 2 kg/h to 5 kg/h through [Formula: see text] 5,000 kg/h. Observed sources include gas processing facilities, storage tanks, pipeline leaks, and well pads, as well as a coal mine venting shaft. Overall, plume enhancements and inferred fluxes follow a lognormal distribution, with the top 10% emitters contributing 49 to 66% to the inferred total point source flux of 0.23 Tg/y to 0.39 Tg/y. With the observed confirmation of a lognormal emission distribution, this airborne observing strategy and its ability to locate previously unknown point sources in real time provides an efficient and effective method to identify and mitigate major emissions contributors over a wide geographic area. With improved instrumentation, this capability scales to spaceborne applications [Thompson DR, et al. (2016) Geophys Res Lett 43(12):6571-6578]. Further illustration of this potential is demonstrated with two detected, confirmed, and repaired pipeline leaks during the campaign.

SUBMITTER: Frankenberg C

PROVIDER: S-EPMC5024631 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region.

Frankenberg Christian C Thorpe Andrew K AK Thompson David R DR Hulley Glynn G Kort Eric Adam EA Vance Nick N Borchardt Jakob J Krings Thomas T Gerilowski Konstantin K Sweeney Colm C Conley Stephen S Bue Brian D BD Aubrey Andrew D AD Hook Simon S Green Robert O RO

Proceedings of the National Academy of Sciences of the United States of America 20160815 35

Methane (CH4) impacts climate as the second strongest anthropogenic greenhouse gas and air quality by influencing tropospheric ozone levels. Space-based observations have identified the Four Corners region in the Southwest United States as an area of large CH4 enhancements. We conducted an airborne campaign in Four Corners during April 2015 with the next-generation Airborne Visible/Infrared Imaging Spectrometer (near-infrared) and Hyperspectral Thermal Emission Spectrometer (thermal infrared) im ...[more]

PMID: 27528660

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Dataset Information

Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region.

Publications

Airborne methane remote measurements reveal heavy-tail flux distribution in Four Corners region.

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