Methane emissions from subglacial meltwater of three alpine glaciers in Yukon, Canada

A groundbreaking study reveals that subglacial meltwater from three alpine glaciers in Yukon, Canada—Dusty, Kluane, and Donjek—serves as a significant source of methane (CH4) to the atmosphere. Methane concentrations in these meltwaters were 45 to 250 times higher than atmospheric equilibrium levels, while CO2 concentrations were depleted, indicating that subglacial environments under alpine glaciers may contribute more to global CH4 emissions than previously recognized. Stable isotopic analysis of CH4 suggested both biotic and abiotic sources, with potential bacterial oxidation altering the signatures. Surprisingly, no correlation was found between CH4 levels and meltwater chemistry or glacier size, challenging existing assumptions about subglacial CH4 dynamics. This research, published in Arctic, Antarctic, and Alpine Research, expands our understanding of methane emissions from glacial systems beyond Greenland and Iceland.

Sapper, S. E., Jørgensen, C. J., Schroll, M., Keppler, F., & Christiansen, J. R. (2023). Methane emissions from subglacial meltwater of three alpine glaciers in Yukon, Canada. Arctic, Antarctic, and Alpine Research, 55(1). https://doi.org/10.1080/15230430.2023.2284456