The Intergovernmental Panel on Climate Change concludes that climate change has already caused substantial damages at the current 1.2°C of global warming and that warming of 1.5°C would elevate risks of a wide-range of climate tipping points. For example, wet-bulb temperatures are already exceeding safe levels, and the melting of the Greenland and West Antartic ice sheets would lead to over ten metres of sea level rise, representing an existential threat to coastal cities, low-lying nation states, and human wellbeing worldwide. We call for a broad scientific discussion about a stricter and more ambitious climate target of 1.0°C by the end of this century. Comprehensive electrification and highly renewable energy systems offer a pathway to sub-1.5°C futures through rapid defossilisation and large-scale, electricity-based carbon dioxide removal. Independent scenarios show that restoring a stable and safe climate is attainable with coordinated policy and economic support.