Last week an extraordinary, scary story made climate headlines around the world: a melting Arctic could release an immense amount of methane that would dramatically increase global warming and cost the world a phenomenal $60tn. Fortunately, it is just a scare story.
This work of horror comes from an opinion piece (not a science article) in the magazine Nature. It assumes, with a single reference to an obscure Russian journal, that the entire methane deposits from the East Siberian Arctic Shelf will be released over the next 12 years. But Nature’s own review concludes “catastrophic, widespread dissociation of methane gas hydrates will not be triggered by continued climate warming at contemporary rates over timescales of a few hundred years”.
The claim of a $60tn cost is based on the economic model that, in a previous version, was used for the infamous Stern review of the economics of climate change. In an academic meta-study of all economic models, its cost estimate was found to be an extreme outlier. Since then, the model has been updated to become 30 per cent more pessimistic.