An emerging methane feedback in the Arctic. It’s something that, since last summer, I’ve been calling the Arctic Methane Monster. A beast of a thing composed of giant reserves of sea bed methane and an immense store of carbon locked away in Arctic tundra.

How dangerous and vicious the monster ends up being to a world set to rapidly warm by humans depends largely on three factors. First — how fast methane is released from warming stores in the sea bed. Second — how swiftly and to what degree the tundra carbon store is released as methane. Third — how large the stores of carbon and methane ultimately are.

(Thawing permafrost and organic carbon in Yedoma region of Russia. Image source: NASA.)

On the issue of the first and third questions, scientists are divided between those like Peter Wadhams, Natalia Shakhova and Igor Simeletov who believe that…