Fig. 2.

Fragile heat: the overlap between state fragility, extreme heat, and nuclear and biological catastrophic hazards. GCM model data [from the WorldClim database (45)] was used to calculate mean annual warming rates under SSP3-7.0 and SSP5-8.5. This results in a temperature rise of 2.8 °C in ∼2070 (48) for SSP3-7.0, and 3.2 °C for SSP5-8.5. The shaded areas depict regions where MAT exceeds 29 °C. These projections are overlapped with the 2021 Fragile State Index (FSI) (49). This is a necessarily rough proxy because FSI only estimates current fragility levels. While such measurements of fragility and stability are contested and have limitations, the FSI provides one of the more robust indices. This Figure also identifies the capitals of states with nuclear weapons, and the location of maximum containment Biosafety Level 4 (BS4) laboratories which handle the most dangerous pathogens in the world. These are provided as one rough proxy for nuclear and biological catastrophc hazards.