Mapping multi-sectoral methane emissions across Queensland’s gas production areas

Abstract

If the evolution of methane satellite technology leads to credible estimates of inter-annual regional emission trends, the need for effective attribution (across sectors) of that top-down data could become critical. This poses a particular challenge for Queensland’s Surat Basin, given the complexity of disentangling the various emission sources – the highly distributed coal seam gas infrastructure is intermingled with grazing cattle, feedlots, farm dams, groundwater bores, landfills, wastewater treatment plants, coal mines and abandoned coal exploration holes. Emissions from many of those sources are poorly understood. We generate spatially disaggregated, time-series estimates of Queensland’s methane emissions, integrating the best available scientific knowledge across all source types, and novel summaries of previously unaccounted for methane sources. The results identify the challenges for effectively attributing top-down methane concentration measurements to sector-specific fluxes in the Surat Basin; and the risk that planners misunderstand causality of any long-term changes in regional methane production, as the quality of satellite-based estimates improves.