According to one of the authors of the IPCC's special report on the impacts of global warming of 1.5°C above pre-industrial levels, reaching this target is 'technically possible, [but] it's extremely improbable, absent a real sea change in the way we evaluate risk. We are nowhere near that' (Drew Shindell in Milman 2018, September 27). The fulfilment of its goals depends on creating a positive cycle of climate action that will raise ambition over time among state and non-state actors.