ABSTRACT

Methane, a greenhouse gas with significantly higher global warming potential than carbon dioxide, is a critical target for climate change mitigation under the Global Methane Pledge, which aims for 30% emissions reduction by 2030. Accurately measuring fugitive methane emissions is challenging due to their uncontrolled, sporadic and diffuse nature. This study evaluates a trailer-mounted Quantum Gas Lidar system for detecting and quantifying fugitive methane emissions from legacy coal exploration bores within onshore gas fields. The system uses an infrared laser to excite methane molecules, enabling infrared laser spectroscopy for high-resolution spatial and temporal detection and measurement of otherwise difficult-to-quantify emissions in both day and night-time conditions. Long-term field measurements demonstrated that continuous monitoring is essential to characterise emission variability and minimise weather-induced measurement artefacts. Our results demonstrate that Quantum Gas Lidar offers significant advantages over traditional methods, particularly in its ability to provide real-time visualisation and quantification of emission dynamics. This technology advances our capability to achieve Global Methane Pledge targets through improved environmental monitoring.