Could Four Billion People Die at 3°C?

The 2025 “Planetary Insolvency” report presents a risk matrix that lists “>4 billion deaths” for 3 °C warming and “>2 billion deaths” for 2 °C, but the authors clarify these figures are not forecasts. They are illustrative orders of magnitude derived from limited research, not specific mortality projections. The report acknowledges that detailed data on large-scale loss of life are lacking.