Geospatial\nLife Cycle Analysis of Greenhouse Gas Emissions\nfrom US Liquefied Natural Gas Supply Chains

Growth in US liquefied\nnatural gas (LNG) exports has increased\nconcerns about the climate impacts of methane leakage along LNG supply\nchains. Current life cycle analysis (LCA) models of US LNG supply\nchains are based on emission estimates in national inventories that\nhave been demonstrated to significantly underestimate emissions. In\naddition, recent top–down measurements of methane emissions\nexhibit significant subnational spatial and temporal variations across\noil and gas (O&G) basins. In this study, we develop a geospatial,\nmeasurement-informed LCA model that incorporates recent top–down\nmethane measurements to examine regional differences in greenhouse\ngas (GHG) emission intensity of US LNG supply chains for delivery\nto Europe and Asia. For every megajoule of LNG shipped from the US,\nthe energy-allocated GHG emission intensity of the Permian-UK LNG\nsupply chain is 42% higher compared to the Marcellus-UK LNG supply\nchain. Differences in basin-specific, measurement-informed inventories\nare a key driver of disparities in supply chain LNG emission intensity.\nDeveloping measurement-informed, supply chain-specific lifecycle GHG\nemission assessments is critical to enabling a global market for differentiated\nnatural gas.