Fig. 2: Time of First Emergence (ToFE) of Day Zero Drought (DZD) event and global hotspot regions based on CESM2-LE ensemble simulations under the SSP3-7.0 scenario.

a Spatial distribution of the decadal ToFE of DZD events across the globe from 1900 to 2100. Colored shading indicates the first decade during which DZD becomes statistically attributable to anthropogenic climate change, defined as the first decade in which the Fraction of Attributable Risk is greater than 0.99 (FAR ≥ 0.99). Gray regions indicate grid cells where no DZD event attributable to anthropogenic climate change is projected to emerge before 2100. For regions with reservoirs, the ToFE is considered to be the first decade after the year of completion (Supplementary Fig. 6) of their respective reservoirs, when all DZD criteria are simultaneously met. By aligning the emergence timing with the operational onset of water storage infrastructure to reflect the real-world system resilience dynamics. The black stars denote the locations of the reservoirs threatened by DZD emergence. b Circular diagram illustrating the temporal distribution of ToFE by decades. The color scale indicates the percentages of grid cells (land areas) experiencing their ToFE distribution in each decade from 1900 to 2100. It provides a temporal overview of how the ToFE is distributed over time and the trends in DZD emergence.