WorldView-3 Satellite Maps Methane Plumes At Very High Spatial Resolution.

This work presents an assessment of the potential of WordView-3 satellite for the mapping of methane point source emissions at very high spatial resolution. The 3.7 m spatial resolution of WV-3 in the shortwave infrared (SWIR) combined with a high-quality noise, rich spectral configuration and pointing capabilities (daily or better revisit time), can be of great support in the global methane reduction activities. The proposed retrieval methodology is based on a multiple linear regression of six SWIR bands barely affected by methane absorption against the B7 (2235-2285 nm) that is positioned at a highly-sensitive methane absorption region. The end-to-end sensitivity analysis of the proposed methane retrieval has helped to understand retrieval errors and detection limits. The potential of WV-3 for methane mapping has been further tested under real-case studies with a positive detection of 26 different point source emissions covering different methane hotspot regions such as the O&G extraction fields in Algeria and Turkmenistan, and the Shanxi coal mining region in China. Under these real-case scenarios, we have proven the usefulness of the unique spatial resolution of the mission to even pinpoint to very small leaks (<100 kg/h) from oil pipelines in Turkmenistan. The methane flux rate of these real-case plumes has been quantified with an uncertainty k=1 in the range of 15-40% largely dominated by the uncertainty on the wind speed data.