Attribution and projection of the summer 2022 compound dry and hot extreme in the Northern Hemisphere

Under the context of global warming, climate and weather extremes (e.g., droughts, high temperature extremes) take a heavy toll on natural and human systems. It has been reported that the concurrence of droughts and hot extremes (CDHEs) in summer 2022 in the Northern Hemisphere (NH) have led to reduced water resources/crop yield and increased health risks. While assessments of droughts and heatwaves in summer 2022 have been noted, the assessment of these extremes from a compound event perspective is still limited. In this study, we analyzed the rarity of CDHEs in summer 2022 across the NH, detected anthropogenic influence on CDHEs area, and projected the likelihood under different warming levels based on observations from ERA5 and simulations from the Sixth Phase of the Coupled Model Intercomparison Project (CMIP6). Our results illustrate that severe CDHEs in summer 2022 across the NH mainly occur in central North America, Europe, and south China. Event attribution analysis shows that CDHEs area in summer 2022 in the NH would not have occurred without anthropogenic global warming. The CDHEs area like 2022 is projected to occur more likely, particularly under SSP585 in a 4°C warming world. This study provides useful insights for advancing our understanding of compound extremes during summer 2022 across the NH.