Across vast swaths of the northern hemisphere’s higher reaches, frozen ground holds billions of tonnes of carbon. As global temperatures rise, this “permafrost” land is at increasing risk of thawing out, potentially releasing its long-held carbon into the atmosphere. Abrupt permafrost thaw is one of the most frequently discussed “tipping points” that could be crossed in a warming world. However, research suggests that, while this thawing is already underway, it can be slowed with climate change mitigation. Yet, what is irreversible is the escape of the carbon that has been – and is being – emitted. The carbon released from permafrost goes into the atmosphere and stays there, exacerbating global warming. In short, what happens in the Arctic does not stay in the Arctic. Permafrost and the global climate Permafrost is ground that has been frozen for at least two consecutive years. Its thickness ranges from less than one […]