Greenhouse Gas Emission Monitoring with the GHGSat Constellation: Advancing High-Resolution Methane Monitoring 

As of late 2025, the GHGSat constellation has expanded to 14 high-resolution (~25 m GSD) methane-sensitive satellites capable of detecting, attributing, and quantifying emissions down to ~100 kg/hr. To enhance the actionable value of these observations, current research focuses on refining source rate quantification and deepening the understanding of the parameters that dictate detection limits in diverse environments. We are characterizing the influence of observation geometry, wind speed, and retrieval noise on the probability of detection (PoD) for specific source rates. By isolating these factors, we aim to provide more site-specific performance metrics across the global constellation. Simultaneously, to improve quantification accuracy, we are investigating how wind field variability, local elevation, and source geometry (e.g., point vs. area sources) affect plume transport and subsequent flux estimates. This integrated approach is particularly critical for characterizing emissions in complex industrial environments like landfills. Finally, we provide a status update on the GHGSat fleet, including our dedicated CO₂ sensor and an overview of upcoming satellite launches.