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

中文翻译：

---

使用四个连续的飞机乙烷测量，对美国中南部和东部的油气乙烷和甲烷排放进行分析

在过去的十年中，为了更好地了解美国石油和天然气（O＆G）行业的甲烷（CH4）排放量，已经做了很多工作。乙烷（C2H6）是与热产生的CH4共同排放的气体，在美国主要由O＆G部门排放。在这项研究中，我们对200小时的大气边界层C2H6测量值进行了反分析，以估算美国O＆G部门的C2H6排放量。作为美国大气碳与运输（ACT）飞机活动的一部分，收集了2017-2019年的测量数据，涵盖了美国中部和东部的大部分地区。我们发现，对于秋季，冬季和春季运动，C2H6数据始终超过根据EPA O＆G泄漏率估算值预期的值超过50％。来自2019年夏季数据集的C2H6观测结果显示，由于复杂的气象条件或排放的时间变化，中南部地区C2H6的增幅显着降低，这无法与其他三个季节的数据相吻合。将秋季，冬季和春季C2H6的后排放估算值与O＆G CH4排放清单相结合，我们估计O＆G CH4排放量比EPA清单值大48-76％。气体成分数据的不确定性限制了使用C2H6替代O＆G CH4排放的准确性。这些限制可以通过提高行业收集的气体成分数据的可追溯性来解决。可能是由于复杂的气象条件或排放的时间变化。将秋季，冬季和春季C2H6的后排放估算值与O＆G CH4排放清单相结合，我们估计O＆G CH4排放量比EPA清单值大48-76％。气体成分数据的不确定性限制了使用C2H6替代O＆G CH4排放的准确性。这些限制可以通过提高行业收集的气体成分数据的可追溯性来解决。可能是由于复杂的气象条件或排放的时间变化。将秋季，冬季和春季C2H6的后排放估算值与O＆G CH4排放清单相结合，我们估计O＆G CH4排放量比EPA清单值大48-76％。气体成分数据的不确定性限制了使用C2H6替代O＆G CH4排放的准确性。这些限制可以通过提高行业收集的气体成分数据的可追溯性来解决。气体成分数据的不确定性限制了使用C2H6替代O＆G CH4排放的准确性。这些限制可以通过提高行业收集的气体成分数据的可追溯性来解决。气体成分数据的不确定性限制了使用C2H6替代O＆G CH4排放的准确性。这些限制可以通过提高行业收集的气体成分数据的可追溯性来解决。