Emergency! Emergency! There’s no doubt it’s an emotive word to use about climate change and yet it might be the only one that captures the scale and immediacy of the problem. The description has been around since Al Gore used it during a provocative 2004 talk at Yale University. He told students it was “intended to convey what it conveys – that this is a crisis with an unusual sense of urgency attached to it”. Over the next decade ‘climate emergency’ became the rallying cry at public marches on climate change across the world.