Fig. 3.

Global and regional heat stress projected as a function of global warming amounts. (A) Global (land) heat stress sensitivity to global air temperature changes, in which lines are medians calculated from the CMIP5 ensemble and the shaded regions span the 25th–75th percentiles. Note that heat stress is defined here as the mean annual number of days exceeding a threshold temperature (40.6 °C, 35 °C, and 37.6 °C for the HI, SWBGT, and DB temperatures, respectively). At this global scale, these metrics are area-averaged. A, Inset continues the curves to 4 °C warming above PI, with limits in A indicated by the black box. (B) The same as in A but for the named locations, with different units on the y axes. Series on B, Inset axes continues the respective curves from B to 4 °C.