Annual probability of occurrence of a heat waves with apparent temperature peaks greater than 40 °C and 55 °C. (a–c), Probability of occurrence of heat waves with AT
≥ 40 (AT40C) calculated at each grid point for all model years with global mean temperature anomaly relative to 1861–1880 at 1.5, 2, and 4 degrees warming (see Fig. 2), respectively. (d–f), as (a–c) but for occurrence of heat waves with AT
≥ 55 (AT55C). This figure has been produced using R version 3.3.2 (https://cran.r-project.org/).