Advances and Challenges in Methane Emission Measurement in the Oil and Gas Sector: A Review

Methane emissions from the oil and gas sector are a major contributor to climate change. It is essential to monitor and mitigate these emissions. In this review, sources of methane emissions, available monitoring techniques, emission estimation models, associated uncertainty, and newly emerging technologies, including AI-based monitoring techniques, are critically evaluated. A review was conducted following the PRISMA 2020 guidelines. A total of 480 records were retrieved from four databases: Scopus, Web of Science, ScienceDirect, and Google Scholar. Out of these, 126 studies were included in the review. The results showed that upstream activities contribute around 85% of total methane emissions from the O&G sector. However, a single monitoring technique is not sufficient to be used under all circumstances, and thus, hybrid monitoring frameworks are required. Several knowledge gaps, including a lack of consistent monitoring protocols, a lack of data from developing regions, especially the Middle East, and a high level of uncertainty associated with the emission estimates, are pinpointed. The review provides a comprehensive assessment of methane emissions from the O&G sector, including emission sources, monitoring, estimation, associated uncertainty, and newly emerging AI-based monitoring techniques, and presents a unified framework to support future mitigation and decision-making.