Global Detection and Analysis of Methane Plumes in 2024 Using TROPOMI Observations

Methane (CH₄) is a potent greenhouse gas that plays a significant role in global warming, with over 60% of CH₄ emissions attributed to human activities. A substantial portion of these anthropogenic emissions originates from a small number of super-emitters, making their monitoring crucial for understanding emission patterns and implementing targeted mitigation strategies. The TROPOspheric Monitoring Instrument (TROPOMI), onboard the ESA Sentinel-5P satellite, provides daily global observations of methane mixing ratios at high spatial resolution, enabling the detection and analysis of plumes associated with these super-emitters.

To detect methane plumes globally in TROPOMI data, a two-step machine learning pipeline is employed, with weekly results now officially part of the Copernicus Atmosphere Monitoring Service (CAMS) products. The first step utilizes a convolutional neural network to identify plume-like structures in the methane data. A support vector classifier is then applied to filter out retrieval artifacts, ensuring the accurate identification of true methane emissions. Detected plumes are categorized by emission rate, and human experts conduct final verifications. In this study, we present the results for the full year 2024, during which a total of 2,311 methane plumes were identified, providing a comprehensive overview of global super-emitter activity. Preliminary analysis based on bottom-up emission inventories shows that the majority of plumes are associated with oil and gas production, landfills, and coal mining activities.

This study provides a detailed analysis of methane plume detections for 2024, highlighting temporal variations and regional hotspots. By focusing on the detected plumes rather than the detection methodology, this work delivers valuable insights into the spatial and temporal dynamics of methane emissions. The findings contribute to the growing body of knowledge required to address super-emitter mitigation and support informed policymaking for reducing global methane emissions.