Predicted frequency of future bleaching events in the 2030s and 2050s under business-as-usual emissions scenario (A1B)

Figure 4.4 Frequency of future bleaching events in the 2030s and 2050s, as represented by the percentage of years in each decade where a NOAA Bleaching Alert Level 2 (i.e., severe thermal stress) is predicted to occur. Predictions are based on an IPCC A1B (business-as-usual) emissions scenario and adjusted to account for historical temperature variability but not adjusted by any other resistance or resilience factors.

(From Reefs at Risk Revisited, courtesy of World Resources Institute. Data adapted from Donner [2009], “Coping with Commitment: Projected thermal stress on coral reefs under different future scenarios.”)