Bridger Photonics Incorporated, 2310 University Way Bldg 4-4, Bozeman, Montana 59715, United States.
Environ Sci Technol. 2023 Aug 22;57(33):12234-12241. doi: 10.1021/acs.est.3c00229. Epub 2023 Aug 10.
Aerial LiDAR measurements at 7474 oil and gas production facilities in the Permian Basin yield a measured methane emission rate distribution extending to the detection sensitivity of the method, 2 kg/h at 90% probability of detection (POD). Emissions are found at 38.3% of facilities scanned, a significantly higher proportion than reported in lower-sensitivity campaigns. LiDAR measurements are analyzed in combination with measurements of the heavy tail portion of the distribution (>600 kg/h) obtained from an airborne solar infrared imaging spectrometry campaign by Carbon Mapper (CM). A joint distribution is found by fitting the aligned LiDAR and CM data. By comparing the aerial samples to the joint distribution, the practical detection sensitivity of the CM 2019 campaign is found to be 280 kg/h [256, 309] (95% confidence) at 50% POD for facility-sized emission sources. With respect to the joint model distribution and its confidence interval, the LiDAR campaign is found to have measured 103.6% [93.5, 114.2%] of the total emission rate predicted by the model for equipment-sized emission sources (∼2 m diameter) with emission rates above 3 kg/h, whereas the CM 2019 campaign is found to have measured 39.7% [34.6, 45.1%] of the same quantity for facility-sized sources (150 m diameter) above 10 kg/h. The analysis is repeated with data from CM 2020-21 campaigns with similar results. The combined distributions represent a more comprehensive view of the emission rate distribution in the survey area, revealing the significance of previously underreported emission sources at rates below the detection sensitivity of some emissions monitoring campaigns.
在二叠纪盆地的 7474 个石油和天然气生产设施进行的航空激光雷达测量得出了一个扩展到该方法检测灵敏度的甲烷排放率分布，在 90%检测概率（POD）下为 2 千克/小时。在扫描的设施中有 38.3%发现了排放物，这一比例明显高于在敏感性较低的测量活动中报告的比例。激光雷达测量结果与 Carbon Mapper（CM）进行的机载太阳红外成像光谱测量活动中获得的分布的重尾部分（>600 千克/小时）的测量结果进行了分析。通过拟合对齐的激光雷达和 CM 数据，发现了一个联合分布。通过将航空样本与联合分布进行比较，发现 CM 2019 年测量活动在 50% POD 下，设施规模排放源的实际检测灵敏度为 280 千克/小时[256,309]（95%置信区间）。对于联合模型分布及其置信区间，发现激光雷达测量活动测量了模型预测的设备规模排放源（直径约 2 米）排放率超过 3 千克/小时的总排放率的 103.6%[93.5,114.2%]，而 CM 2019 年测量活动测量了直径 150 米的设施规模排放源（排放率超过 10 千克/小时）的相同数量的 39.7%[34.6,45.1%]。对来自 CM 2020-21 年测量活动的类似数据进行了类似的分析，得到了类似的结果。联合分布代表了调查区域排放率分布的更全面视图，揭示了以前在一些排放监测测量活动的检测灵敏度以下被低估的排放源的重要性。
