Methane Technical Section Q&A: One Atmosphere, Many Measurements—Reconciling Methane Signals Across Satellites and Sensors

Arvind Ravikumar, SPE, is the Frank W. Jessen Centennial Fellow in Petroleum Engineering and co-director of the Center for Energy and Environmental Systems Analyses (CEESA), at the University of Texas at Austin. He has published more than 60 peer-reviewed articles on greenhouse-gas measurement, life-cycle assessment, and technoeconomic modeling. Ravikumar has also served as lead investigator for several large field campaigns on methane emissions across the US oil and gas supply chain. He holds a PhD degree from Princeton University.

MTS: Can you briefly introduce the Energy Emissions Modeling and Data Lab (EEMDL) and the Center for Energy and Environmental Systems Analyses (CEESA)?

Ravikumar: EEMDL is a collaborative initiative among the University of Texas at Austin, Colorado State University, and the Colorado School of Mines. It was established to develop transparent models and public data sets that support more accurate greenhouse-gas accounting across global oil and gas supply chains.

EEMDL sits within CEESA at UT Austin. CEESA brings together faculty, postdoctoral researchers, students, and staff working on energy and environmental systems, including methane emissions, hydrogen, carbon removal, and low-carbon energy pathways. EEMDL is one of the center’s major projects.

MTS: What motivated EEMDL to focus so strongly on methane measurement and emissions intelligence?

Ravikumar: Around 2020 and 2021, a central challenge in methane research was the gap between measured emissions and official inventory estimates. This discrepancy reflected, in part, the reliance of conventional inventories on outdated emission factors, as well as their limited ability to capture large, intermittent “superemitter” events. Although such events may occur infrequently, their high emission rates can make them disproportionate contributors to total methane emissions across the oil and gas supply chain.

At the same time, methane measurement technology was advancing rapidly. Continuous monitors, drones, vehicles, aircraft, and satellites were producing far more observations than ever before. The challenge shifted from a lack of measurement data to one of interpreting those measurements. EEMDL was created to build the tools and analytical methods needed to convert diverse methane measurements into information that supports mitigation, policy, and operational decisions.

MTS: Why is methane such a critical issue now for both industry and climate stakeholders?

Ravikumar: Methane matters not only for climate but also for business, regulation, operations, and energy affordability. As climate-related policies increasingly shape global gas markets, methane performance is becoming directly linked to market access and competitiveness.

For US liquefied natural gas (LNG) exporters, this is especially important because major customers in Europe are moving toward lower-emission energy supply chains. If methane intensity standards are applied to LNG imports, pressure to demonstrate low methane emissions will extend beyond LNG terminals to upstream producers, pipeline operators, and the broader US natural gas supply chain.

Methane mitigation also supports energy affordability and climate goals. Preventing methane from escaping keeps valuable natural gas in the energy system, which becomes increasingly important as LNG exports and electricity demand grow. At the same time, methane reduction remains one of the lowest-cost and most practical greenhouse-gas mitigation strategies available for oil and gas systems today.

MTS: How would you explain the difference between top-down and bottom-up methane measurement?

Ravikumar: The distinction is useful, but it is not absolute. Traditionally, “top-down” referred to remote measurements, while “bottom-up” referred to measurements taken closer to the emission source. As methane detection technologies have advanced, however, the boundary between these categories has become increasingly scale dependent.

In general, bottom-up measurements provide source-specific information. They can identify emissions from individual components or equipment, such as flanges, pneumatic controllers, or exhaust stacks. These methods offer detailed, high-resolution data, but they are often time-intensive and may cover only a limited number of sources.

Top-down measurements typically capture aggregate emissions at the site, regional, or basin scale. Aircraft and satellite observations can survey larger areas more quickly, but they often provide less detail about the specific source of emissions. Ultimately, methane measurement should be viewed as a multiscale system, spanning source-level, site-level, facility-level, and regional observations.

MTS: Why is it not enough to rely on a single measurement approach?

Ravikumar: Relying on a single measurement approach is insufficient because methane emissions are complex, variable, and often intermittent. Each technology provides only part of the picture: An aerial survey may estimate the emission rate during a flyover, while continuous monitoring systems may better capture how often emissions occur and how long they last.

The current frontier in methane research is therefore not simply collecting more data but integrating data from satellites, aircraft, drones, ground-based systems, and continuous monitors. Combining these technologies can provide a more complete and actionable understanding of methane emissions across the supply chain.

MTS: What does a credible measurement-informed methane inventory look like in practice?

Ravikumar: A credible measurement-informed methane inventory integrates all available evidence in a scientifically defensible way, including operational data, source-specific inventories or emission factors, and measurements from different technologies. This is increasingly important for policy and voluntary reporting frameworks, such as the Oil and Gas Methane Partnership, which encourages companies to combine measurement data with source-specific inventories to improve methane emissions reporting.

In practice, a credible inventory puts the puzzle pieces together: what operations suggest, what source-level calculations estimate, and what measurements observe. The appropriate integration method may vary by source type, facility type, or spatial scale. While measurement-only inventories may be suitable at regional or national scales, operator-, asset-, or facility-level inventories should interpret measurements alongside operational knowledge and source-level information.

MTS: What is most exciting in EEMDL’s current work on integrating methane data?

Ravikumar: One of the most exciting areas of EEMDL’s current work is integrating methane measurement data with operational information. EEMDL works with operators across the oil and gas supply chain to understand what different measurements show and how they can be incorporated into existing inventories, rather than treated as separate or competing estimates.

This work is important because operators often must develop multiple versions of methane inventories. EEMDL aims to develop harmonized methods that combine measurements, operational knowledge, and source-specific data into the best available inventory at different spatial scales.

Another exciting direction is extending this framework from individual facilities to full natural gas supply chains, enabling carbon intensity assessments for LNG exports, power generation, data centers, hydrogen production, petrochemicals, and other gas-dependent products.

MTS: What makes EEMDL’s approach distinctive?

Ravikumar: A distinctive feature of EEMDL’s approach is that it does not privilege one measurement method over another. Rather than treating satellites, aircraft, continuous monitors, or source-level measurements as inherently superior, EEMDL focuses on understanding what information each technology provides and how it can improve emissions inventories.

EEMDL’s approach is also built around direct engagement with oil and gas operators, because operational context is essential for interpreting measurement data. By bringing together measurement scientists, data analysts, inventory developers, and operators, EEMDL integrates multiple forms of evidence into a coherent picture of methane emissions, distinguishing it from conventional monitoring efforts focused on a single technology or data set.

MTS: Can you share an example where multiple measurement scales changed the interpretation of emissions?

Ravikumar: One example involved developing a methane emissions inventory for uncontrolled tanks. Aerial survey measurements were used to detect methane emissions from a large number of tanks, providing emission rates at the time of observation. However, aerial measurements alone could not determine how frequently emissions occurred or how long they lasted.

To reconcile these data, EEMDL combined aerial survey results with engineering-based calculations, continuous monitoring data, and operator-provided contextual information. Continuous monitors helped characterize the frequency and duration of flashing events, while aerial surveys provided emission-rate information. By integrating these data streams, EEMDL developed a more accurate tank emissions inventory.

MTS: What would success look like if methane data were integrated into a unified decision system?

Ravikumar: Success would mean connecting satellites, aerial surveys, continuous monitors, operational data, and inventories into a single methane intelligence platform that can help operators, regulators, and other stakeholders understand emissions across different spatiotemporal scales.

This would shift methane management from reactive mitigation toward predictive and proactive mitigation. Instead of only detecting and repairing leaks after they occur, artificial intelligence and machine learning could help anticipate when and where emissions are likely to happen, enabling early warning, predictive maintenance, and prevention of large emission events.

MTS: How does methane mitigation fit into the future of natural gas and energy policy landscape over the next 5 years?

Ravikumar: Methane mitigation is becoming central to the future of natural gas because demand is growing from LNG exports, power generation, and data centers. Lower methane emissions can support market access as international buyers increasingly differentiate natural gas and LNG by emissions intensity, while also improving affordability by keeping valuable product in the pipeline.

Policy is also likely to evolve from command-and-control rules toward more flexible, performance-based frameworks. With better methane measurement and analytics, regulators could set methane emissions or intensity targets while allowing operators to choose the most cost-effective ways to meet them, supported by credible measurement-informed inventories and transparent emissions accounting.