Fig. 6: Substantially increased extreme exposure due to climate change.
From: Compounding future escalation of emissions- and irrigation-induced increases in humid-heat stress
Impacts of all forcings (greenhouse gas emissions change, land-use change, irrigation change, etc.) on the annual hours exposed to dry- (a, c) and moist-heat extremes (b, d) under SSP1-2.6 (a, b and SSP3-7.0 (c, d). The extremes are defined as the exceedance of the 99th percentile values of 2-metre air temperature (T2m) and wet-bulb temperature (Tw) of the historical simulations (1985–2014) without irrigation (Hist_NOI), as shown in Fig. 5a, b. The calculation of impacts of forcings is conducted by subtracting the annual hours of the same events in the historical simulation with irrigation (Hist_IRR: 1985–2014) from those of future simulations with irrigation (SSP1_IRR and SSP3_IRR: 2045-2074), as shown in Fig. 8. The difference in annual hours exposed to dry- (e) and moist-heat extremes (f) under two scenarios (calculated by subtracting the annual mean hours in SSP1_IRR from SSP3_IRR). The values shown here are the mean values across all three ensemble members. Hatches indicate that all three ensemble members agree on the direction of change (≤-10 or ≥+10 hours yr−1). The spatial coverage of the IPCC reference regions32 used in this study is indicated by solid lines, dashed lines, and dash-dotted lines.
