Ethane: A Key to Evaluating Natural Gas Industrial Emissions

Monday, 15 December 2014
Tara Irene Yacovitch1, Scott C. Herndon1, Mike Agnese1, Joseph R Roscioli1, Cody R Floerchinger1, Walter B Knighton2, Sally E Pusede3, Glenn S Diskin3, Joshua P DiGangi3, Glen W Sachse3, Philipp Eichler4, Tomas Mikoviny5, Markus Müller4, Armin Wisthaler4,5, Stephen A Conley6 and Gabrielle Petron7, (1)Aerodyne Research Inc., Billerica, MA, United States, (2)Montana State University, Bozeman, MT, United States, (3)NASA Langley Research Center, Hampton, VA, United States, (4)University of Innsbruck, Institute of Ion Physics and Applied Physics, Innsbruck, Austria, (5)University of Oslo, Department of Chemistry, Oslo, Norway, (6)University of California Davis, Davis, CA, United States, (7)Cooperative Institute for Research in Environmental Sciences, Boulder, CO, United States
Airborne and mobile-surface measurements of ethane at 1Hz in the Denver-Julesberg oil and gas production basin in NE Colorado reveal a rich set of emission sources and magnitudes. Although ethane has only a mild influence on hemispheric ozone levels, it is often co-emitted with larger hydrocarbons including hazardous air pollutants (HAPs) and ozone precursors that impact local and regional air quality. Ethane/methane enhancement ratios provide a map of expected emission source types in different areas around greater Denver. Links are drawn between the ethane content of isolated methane emission plumes and the prevalence of concomitant HAP and ozone precursor species. The efficacy of using ethane as a dilution tracer specific to the oil & gas footprint will be demonstrated.