During my postdoc at the University of British Columbia, I am investigating the cycling of the potent greenhouse gases methane (CH4) and nitrous oxide (N2O) in the Canadian Arctic. The rapid environmental changes occurring in the Arctic, which is warming at twice the rate of the rest of the world, have the potential to alter greenhouse gas emissions to the atmosphere, potentially creating significant climate feedbacks.
We are collecting measurements from coast guard icebreakers, conducting helicopter-based sampling of rivers in the Canadian Arctic Archipelago, and collecting a year-round time-series at the new Canadian High Arctic Research Station in Cambridge Bay, Nunavut.
Seasonality of CH4 emissions in Cambridge Bay, Nunavut
We are collecting year-round timeseries of CH4 measurements in Cambridge Bay, Nunavut, in a river and the coastal ocean. We have demonstrated that extremely high CH4 concentrations occur in rivers and the surface marine waters during the spring melt period (50 to 1000 times greater than the concentrations throughout the rest of the year), and that this CH4 is rapidly ventilated to the atmosphere when ice cover retreats. In 2018, we used a robotic kayak (the WHOI ChemYak) to obtain three-dimensional maps of CH4 and CO2 distributions during this dynamic melt period. A preprint on this work is available at EarthArXiv. An interview with my coauthor Dr. Anna Michel, one of the developers of the ChemYak is available from WHOI Oceanus.
A multi-year record of greenhouse gas distributions across the North American Arctic Ocean
We are performing vertical profile measurements at repeat stations across the North American Arctic Ocean in collaboration with the Amundsen Science program and Fisheries and Oceans Canada. These results allow us to observe inter-annual variability in gas distributions and predict how greenhouse gas cycling and emissions may change as the Arctic continues to warm. The image below shows where we collected samples in 2015-2017.