Analysis of Oil and Gas Ethane and Methane Emissions in the Southcentral and Eastern United States Using Four Seasons of Continuous Aircraft Ethane Measurements

In the last decade, much work has been done to better understand methane (CH4) emissions from oil and gas (O&G) industry in United States. Ethane (C2H6), a that is co-emitted with thermogenic sources of CH4, emitted US predominantly by O&G sector. this study, we perform an inverse analysis on 200 h atmospheric boundary layer C2H6 measurements estimate Measurements were collected 2017 2019 as part Atmospheric Carbon Transport (ACT) America aircraft campaign encompass central eastern We find for fall, winter, spring campaigns, data consistently exceeds values would be expected based EPA leak rate estimates more than 50%. observations summer set show significantly lower enhancements southcentral region cannot reconciled other three seasons, either due complex meteorological conditions or temporal shift emissions. Combining posterior inventory CH4 emissions, are larger 48%–76%. Uncertainties composition limit accuracy using proxy These limits could resolved retroactively increasing availability industry-collected data.