A researcher from the University of Copenhagen found unexpectedly high levels of methane in the meltwater of three Canadian glaciers, challenging existing beliefs about glacial methane emissions. These findings suggest that methane production beneath glaciers is more widespread than previously thought, raising important questions about carbon cycling in glaciated regions and their impact on climate change.
“We expected to find low values in the meltwater because it is believed that glacial methane emissions require larger ice masses such as vast ice sheets. But the result was quite the opposite. We measured concentrations up to 250 times higher than those in our atmosphere,” explains Sarah Elise Sapper of the University of Copenhagen’s Department of Geosciences and Natural Resource Management..
Sarah Elise Sapper directed the helicopter pilot to land close to the glacier edge to measure the methane in whirlpools of meltwater streaming out. Credit: Sarah Elise Sapper “The meltwater from the surface of glaciers is oxygen-rich when it travels to the bottom of the ice. So we found it quite surprising that all this oxygen is used up somewhere along the way, so that oxygen-free environments form underneath these mountain glaciers. And even more surprising that it happens to such a degree, that microbes start producing methane and we can observe these high methane concentrations in the water flowing out at the glacier edges” states Sarah Elise Sapper.