PLANET EARTH
Methane under the Arctic could trigger a climate feedback loop
WORDS SASCHA PARE
Thawing permafrost due to climate change is releasing methane, a potent greenhouse gas
Deep beneath the permafrost that blankets a group of islands in the
Arctic Ocean lurks a growing and migrating sea of methane. The thick
permafrost, or ground that remains frozen for at least two years, forms a tight seal that has so far prevented millions of cubic metres of methane from wafting out, but there’s no guarantee that the potent greenhouse gas won’t eventually escape. “At present, the leakage from below permafrost is very low, but factors such as glacial retreat and permafrost thawing may ‘lift the lid’ on this in the future,” said Thomas Birchall, a geologist at the University Center in Svalbard in Norway.