William Kunkel , Michael Thorpe, Asa Carre-Burritt, Grant Aivazian, Nicholas Snow, Jacob Harris, Tagert Mueller, Peter Roos

Aerial LiDAR measurements of methane emissions at 7920 oil and gas production facilities in the Permian Basin yield an emission rate distribution extending to the detection sensitivity of the method, 2 kg/h at 90% probability of detection. The LiDAR measurements are analyzed in combination with the heavy tail portion (> 600 kg/h) of a distribution obtained from an intensive airborne solar infrared imaging spectrometry study by Cusworth et al. to yield a more complete emission rate distribution. Comparison of the data sets supports an assessment of the detection sensitivity of the solar infrared study at 300 kg/h at 50% probability of detection. Emissions detected by LiDAR increase the total emission rate for the survey region by a factor of 3.0 after controlling for scale factors such as survey area and number of scans per facility. Additionally, the role of spatial aggregation is highlighted as the cumulative emission rate distribution shifts toward larger source emission rates by a factor of three when detections are aggregated to facility size scales (150 m) rather than resolved to equipment size scales (2 m). The combined distribution derived for this study represents previously underreported emission sources at rates below 300 kg/h resolved at equipment-level spatial precision.