Methane emissions are produced by a variety of natural and anthropogenic sources across different ecosystems, spatial scales and time periods. Quantifying these emissions and removals, and understanding their variability is challenging as the production, oxidation, transport and emission of methane are influenced by a variety of interactions between biological, physical and human disturbance processes. There is also a significant lack of observations in key regions that have been estimated to be major sources, such as tropical forests and heterogeneous Arctic landscapes. Thus, there remains substantial mismatch between bottom-up and top-down estimates, particularly for natural sources such as wetlands, peatlands, inland waters, permafrost and other ecosystems, as well as uncertainties in methane atmospheric oxidation and consumption by bacteria in the soil.
This session aims to promote interdisciplinary collaboration and improve our understanding of methane sources and sinks, their variability, and associated uncertainties across spatial and temporal scales. We encourage studies applying a variety of complementary observational, experimental and modelling approaches, from ecosystem measurements, such as chamber and eddy-covariance techniques, and remote sensing, to inventories, process-based models and Earth system models, as well as atmospheric observations and inversions. We particularly welcome studies that explore upscaling of measurements from ecosystem and landscape scales to integration within regional and global methane budgets, as well as studies that identify and reduce uncertainties in methane source estimates. We welcome contributions addressing all sources of methane with a particular focus on improving the quantification and understanding of the processes involved in natural methane emissions, as well as their representation in models and global budgets.