High concentrations of methane have been discovered in meltwater from three Canadian mountain glaciers, where it wasn’t thought to exist–adding new unknowns to the understanding of methane emissions from Earth’s glaciated regions. Similar to two other glaciers, meltwater in the Canadian Donjek glacier has concentrations of methane up to 250 times higher than those in our atmosphere. Somewhere beneath the ice, there are previously unknown sources of the gas. It may be true elsewhere.
https://phys.org/news/2024-02-methane-discovery-yukon-glaciers-widespread.htm