Mackenzie Delta thermogenic methane distribution, sources, drivers

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Relative to surface biologic production of methane from soils, wetlands, and degrading permafrost, geologic seeps of methane are less well understood. We know that a large amount of methane is emitted from natural geologic seepage, venting oil and gas reservoirs or subsurface gas hydrates. Sporadic studies over the past two decades from provincial and federal scientists have identified huge natural seeps in the Mackenzie Delta. New aircraft studies suggest that geological seepage hotspots are a dominant control on landscape emissions, and that water body sources in the Mackenzie Delta were not the hotspots most global land surface models would expect. This leaves an uncomfortable friction between geologically-based estimates, and the findings of ecosystem scientists working elsewhere in the Arctic who conclude that warming temperatures and a deepening active layer drives increased methane production in large part from water bodies. Are geological emissions of methane in the Mackenzie Delta as prolific as new studies suggest? Could this be happening elsewhere, and do we need to revise our approach to studying Arctic methane?******My proposed research aims to understand geological methane distribution, sources, and drivers in the Mackenzie Delta. The research will focus on collecting data at landscape scales, since the debates are inherently about landscape distribution of sources. The research will involve a mixture of graduate students, undergraduates, and research associates, working alongside identified academic, government, and industry collaborators specialized in Mackenzie Delta methane and related issues (permafrost degradation, petroleum systems, geochemistry, measurement tools). To identify emission hotspots, we will apply landscape-scale (100s km) geochemical survey tools, in combination with satellite data. Within these areas we will undertake detailed investigations of sources and geochemistry, in an effort to understand local distribution, relative rates, and drivers of geological seeps and surface biogenic activity. This research is a natural extension of my experience in oil and gas tracer studies, cold-regions biogenic soil gas studies (including recent work in the Mackenzie Delta), and my keen interest in landscape-scale gas measurement methodologies, which for the first time will come together in a single project.******The results of this interdisciplinary work will be useful for atmospheric scientists, climate modelers, permafrost soil scientists, and geologists interested in petroleum systems and the long-term carbon cycle. Because there is also some focus on identifying biogenic methane, there is the possibility to link this work to permafrost thaw and decomposition of organics, methane from organic-loaded hydrologic systems, and landscape change (thaw-driven landslides, slumps). This research is also designed to connect with the NASA Arctic Boreal Vulnerability Experiment (ABoVE), in which I play a continuing role.**