[Comment] Different futures ahead: why does 1·5°C matter?

Climate change is threatening the health and wellbeing of billions.1 To avert most severe risks of climate change and ensure a safe and liveable planet, global warming must be constrained as much as possible. The core aim of the Paris Agreement is to limit global average temperature increase to ‘well below 2oC’ and pursue efforts to limit warming to 1·5oC above pre-industrial levels.2 The UN, many international agencies, non-government organisations, and climate action groups have focused on achieving this goal (figure).