As permafrost thaw accelerates in northern landscapes, there is great concern and uncertainty about methane emissions from destabilized permafrost carbon and their role in climate feedbacks. Isotope measurements are an important tool for understanding the production and cycling of methane but have primarily focused on measurements of stable carbon isotope ratios (13C).
Recent methodological advances are expanding the use of additional methane isotope measurements and their application to environmental samples. I will present an overview of the full breadth of available methane isotopic measurements, and examples from my own research of how these can be applied to understand methane emissions from permafrost landscapes.
Specifically, I will discuss: 1) how methane hydrogen isotope measurements could be used as a global tracer for high-latitude methane emissions; 2) how methane radiocarbon measurements point to different carbon sources for different emissions pathways in permafrost thaw ponds; and 3) how measurements of clumped isotopes, or multiply substituted isotopologues, can reveal differences in the relative rates of methane production across permafrost landscapes.
More information and registration at Centre for northern studies (CEN) (ulaval.ca)