Thermal stress at different levels of global warming. a–c, Frequency of DHM>2°C×month events with 1.0 °C (a), 1.5 °C (b) and 2.0 °C (c) of global mean warming. Red points represent frequencies above the critical limit for long-term degradation. d, Corals at risk of long-term degradation for constant thermal threshold DHM = 2 °C×month and individual AOGCMs. e, Fraction of the world's coral reef cells (coloured areas) at risk of long-term damage due to frequent coral bleaching events. Frieler, et al., 2012