Senior Editor of The Economist and science writer Oliver Morton, author of The Planet Remade: How Geoengineering Could Change the World, provides a history and overview of climate intervention ideas. The mainstream view of climate action is that it consists of emissions reduction and, to the extent that those reductions fall short, adaptation. But before this consensus crystallised in the 1990s many other ways of limiting or rechannelling the flow of energy through the Earth system were considered. As the world now sails past 1.5ºC warming, this session offers a reappraisal of these alternative ideas.