title: Near-Field Characterization of Methane Emission Variability from a Compressor Station Using a Model Aircraft.
abstract: A model aircraft equipped with a custom laser-based, open-path methane sensor was deployed around a natural gas compressor station to quantify the methane leak rate and its variability at a compressor station in the Barnett Shale. The open-path, laser-based sensor provides fast (10 Hz) and precise (0.1 ppmv) measurements of methane in a compact package while the remote control aircraft provides nimble and safe operation around a local source. Emission rates were measured from 22 flights over a one-week period. Mean emission rates of 14 ± 8 g CH4 s(-1) (7.4 ± 4.2 g CH4 s(-1) median) from the station were observed or approximately 0.02% of the station throughput. Significant variability in emission rates (0.3-73 g CH4 s(-1) range) was observed on time scales of hours to days, and plumes showed high spatial variability in the horizontal and vertical dimensions. Given the high spatiotemporal variability of emissions, individual measurements taken over short durations and from ground-based platforms should be used with caution when examining compressor station emissions. More generally, our results demonstrate the unique advantages and challenges of platforms like small unmanned aerial vehicles for quantifying local emission sources to the atmosphere.
authors.affiliation: †William B. Hanson Center for Space Sciences, University of Texas at Dallas, 800 West Campbell Road, Richardson, Texas 75080, United States.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Nathan
authors.affiliation: ‡Department of Civil and Environmental Engineering, Princeton University, EQuad E-209A, Princeton, New Jersey 08544, United States.|§Center for Mid-Infrared Technologies for Health and the Environment, Princeton University, 70 Prospect Ave., Princeton, New Jersey 08540, United States.
authors.forename: Levi M
authors.initials: LM
authors.lastname: Golston
authors.affiliation: ‡Department of Civil and Environmental Engineering, Princeton University, EQuad E-209A, Princeton, New Jersey 08544, United States.|§Center for Mid-Infrared Technologies for Health and the Environment, Princeton University, 70 Prospect Ave., Princeton, New Jersey 08540, United States.
authors.forename: Anthony S
authors.initials: AS
authors.lastname: O'Brien
authors.affiliation: ‡Department of Civil and Environmental Engineering, Princeton University, EQuad E-209A, Princeton, New Jersey 08544, United States.|§Center for Mid-Infrared Technologies for Health and the Environment, Princeton University, 70 Prospect Ave., Princeton, New Jersey 08540, United States.
authors.forename: Kevin
authors.initials: K
authors.lastname: Ross
authors.affiliation: †William B. Hanson Center for Space Sciences, University of Texas at Dallas, 800 West Campbell Road, Richardson, Texas 75080, United States.
authors.forename: William A
authors.initials: WA
authors.lastname: Harrison
authors.affiliation: ‡Department of Civil and Environmental Engineering, Princeton University, EQuad E-209A, Princeton, New Jersey 08544, United States.|§Center for Mid-Infrared Technologies for Health and the Environment, Princeton University, 70 Prospect Ave., Princeton, New Jersey 08540, United States.
authors.forename: Lei
authors.initials: L
authors.lastname: Tao
authors.affiliation: †William B. Hanson Center for Space Sciences, University of Texas at Dallas, 800 West Campbell Road, Richardson, Texas 75080, United States.
authors.forename: David J
authors.initials: DJ
authors.lastname: Lary
authors.affiliation: ∥Center for Alternative Fuels, Engines, and Emissions, West Virginia University, 395 Evansdale Drive, Morgantown, West Virginia 26505, United States.
authors.forename: Derek R
authors.initials: DR
authors.lastname: Johnson
authors.affiliation: ∥Center for Alternative Fuels, Engines, and Emissions, West Virginia University, 395 Evansdale Drive, Morgantown, West Virginia 26505, United States.
authors.forename: April N
authors.initials: AN
authors.lastname: Covington
authors.affiliation: ∥Center for Alternative Fuels, Engines, and Emissions, West Virginia University, 395 Evansdale Drive, Morgantown, West Virginia 26505, United States.
authors.forename: Nigel N
authors.initials: NN
authors.lastname: Clark
authors.affiliation: ‡Department of Civil and Environmental Engineering, Princeton University, EQuad E-209A, Princeton, New Jersey 08544, United States.|§Center for Mid-Infrared Technologies for Health and the Environment, Princeton University, 70 Prospect Ave., Princeton, New Jersey 08540, United States.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Zondlo
mesh_terms: D000388:Air; D000393:Air Pollutants / Q000032:analysis*; D000401:Aircraft; D000531:Altitude; D001272:Atmosphere / Q000737:chemistry; D008697:Methane / Q000032:analysis*; D059206:Natural Gas / Q000032:analysis*; D013997:Time Factors; D035501:Uncertainty
chemical_list: D000393:Air Pollutants; D059206:Natural Gas; D008697:Methane