This is a problem because the warming heats up the frozen ground around the Arctic Ocean, where there is a massive amount of frozen carbon which, when it thaws, is turned into methane by microbes.
Dette er eit problem fordi oppvarminga varmar opp tundraen kring det arktiske hav der det er massive mengder frosen karbon som, når han smeltar, blir omdanna til metan av mikrobar.