One of the many potential tipping points that worry climate scientists is the possibility of methane escaping as arctic permafrost continues to thaw due to global warming...
Beneath Svalbard’s permafrost, millions of cubic meters of methane are trapped — and scientists have now learned that it can migrate beneath the cold seal of the permafrost and escape. A large-scale escape could create a cycle of warming that would send methane emissions skyrocketing: warming thaws the permafrost, causing more gas to escape, allowing more permafrost to thaw and more gas to be released. Because Svalbard’s geological and glacial history is very similar to the rest of the Arctic region, these migrating deposits of methane are likely to be present elsewhere in the Arctic.
“Methane is a potent greenhouse gas,” said Dr Thomas Birchall of the University Center in Svalbard, lead author of the study in Frontiers in Earth Science. “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.”
Experts have shown that the active layer of permafrost — the upper one or two meters that thaws and re-freezes seasonally — is expanding with the warming climate. However, we know less about how the deeper permafrost is changing, if at all. Understanding this is dependent on understanding the fluid flow beneath the permafrost. If the consistently frozen permafrost grows thinner and patchier, this methane could find it ever easier to migrate and escape, possibly accelerating global warming and exacerbating the climate crisis.
