Closing the methane gap in US oil and natural gas production emissions inventories

Abstract

Methane (CH4) emissions from oil and natural gas systems are an important contributor to greenhouse gas emissions. In the United States, recent synthesis studies of field measurements of CH4 emissions at different spatial scales are ~1.5–2× greater compared to official greenhouse gas inventory (GHGI) estimates, with the production-segment as the dominant contributor to this divergence. Based on an updated synthesis of measurements from component-level field studies, we develop a new inventory-based model for CH4 emissions, for the production-segment only, that agrees within error with recent syntheses of site-level field studies and allows for isolation of equipment-level contributions. We find that unintentional emissions from liquid storage tanks and other equipment leaks are the largest contributors to divergence with the GHGI. If our proposed method were adopted in the United States and other jurisdictions, inventory estimates could better guide CH4 mitigation policy priorities.

Bio

Jeff is a PhD student working at the intersection of energy, economy, and environment, using life cycle assessment tools to better understand the impacts and trade-offs of energy technologies. His current work focuses on incorporating methane emissions into assessment of oil and gas carbon intensity, uncovering the sources of historic underestimation of methane emissions and producing tools to improve our estimates moving forward. Jeff holds an MSc in Oceanography and Coastal Science from Louisiana State University and a BSc in Mechanical Engineering from the University of Alberta.