Methane as a Climate Policy Focus
📌 Methane is a powerful greenhouse gas, responsible for about one-third of current climate warming, making its reduction a key strategy to slow near-term climate change.
⏳ Unlike $\text{CO}_2$, methane has a short atmospheric lifetime of about 10 years, meaning emission cuts yield almost immediate climate benefits.
🌍 The Global Methane Pledge (signed by over 150 countries) aims to cut collective emissions by 30% by 2030 relative to 2020 levels, driving increased monitoring efforts.

Satellite Methane Monitoring Systems
🛰️ The satellite observing system for methane is rapidly growing, broadly divided into total flux mappers (e.g., TROPOMI, GOES-R) for regional analysis and point source imagers (e.g., GHGSat) for high-resolution (down to $10\text{ m}$) facility-scale monitoring.
📊 Instruments like TROPOMI provide daily global coverage at $\sim$kilometers resolution, while newer hyperspectral imagers (like Sentinel-2) designed for land monitoring are being adapted for trace gas sensing.
🧩 A core challenge is mapping diverse sources (natural wetlands vs. anthropogenic sectors like oil/gas, waste, livestock) and their highly variable and intermittent point source emissions.

Inverse Analysis and Permian Basin Study
🧮 The Integrated Methane Inversion (IMI) tool uses atmospheric transport models and satellite observations (like TROPOMI) alongside prior emission estimates in a Bayesian statistical approach to infer improved emission maps at resolutions like $25\text{ km}$.
❄️ Analysis of the Permian Basin revealed a strong seasonal cycle in oil and gas methane emissions, with 50% higher emissions in winter compared to summer, despite non-seasonal production levels.
🌡️ This seasonality is hypothesized to be driven by seasonal variations in liquid storage tank venting (tank flashing) due to colder temperatures reducing gas solubility in separators, increasing the amount vented.

Point Source Monitoring with Sentinel-2
🔭 Sentinel-2's multispectral imager (MSI) bands (11 and 12) in the shortwave infrared region allow for the detection of large methane plumes by analyzing differences/ratios in absorption depths at $\sim 1,650\text{ nm}$ and $2,300\text{ nm}$.
💨 Case study of a compressor station in Turkmenistan showed persistent, very large emissions ($\sim 20\text{ tons/hour}$), equating to $5\%$ of Turkmenistan's reported national oil/gas emissions from that single site.
📉 Diplomatic intervention following discovery correlated with a nine-month cessation of emissions from the Turkmenistan site, demonstrating the impact of satellite monitoring, followed by a return to high emission rates.

Geostationary Observations and Validation
⏱️ GOES satellites offer continuous coverage over the Western Hemisphere (every $10\text{ minutes}$) or targeted regions ($30\text{ seconds}$), enabling the quantification of total mass released during transient events like pipeline blowdowns, unlike LEO satellites which only provide snapshots.
💣 Analysis of pipeline maintenance events (e.g., a $1,200\text{ ton}$ release in Mexico) confirms the value of geostationary monitoring for tracing large, temporary releases across distances.
🤝 Validation of these large-scale satellite retrievals is being conducted via coordinated opportunistic experiments, deploying aircraft, mobile labs, and multiple LEO satellites during known pipeline blowdowns to compare against ground truth measurements.

Key Points & Insights
➡️ Methane mitigation is crucial for near-term climate stabilization due to its high global warming potential and short atmospheric lifespan.
➡️ The IMI tool offers a publicly available ($\text{AWS}$) methodology for integrating satellite data to refine emission inventories at regional scales.
➡️ Weatherization improvements for oil and gas separation equipment could significantly reduce the observed $50\%$ seasonal spike in winter methane emissions in basins like the Permian.
➡️ Current satellite capabilities, especially high-frequency data from GOES, can monitor and quantify massive, short-duration methane releases like pipeline maintenance events, which were previously missed or misattributed.

📸 Video summarized with SummaryTube.com on Dec 15, 2025, 05:28 UTC