Editorials

Due to the greater negative impacts on humans and ecosystems, compound events (CEs) have received increasing attention in China over recent decades. Previous studies mainly considered combinations of frequent hazards (e.g., extreme hot and dry events or heatwaves and extreme precipitation), potentially leading to an inadequate understanding of CEs hotspots, as the occurrence of CEs varies considerably with the diverse hazard types and their temporal sequence (multivariate compound events (MCEs) and temporally compounding events (TCEs)). Here, using daily meteorological observations from 1961 to 2020, we identify 44 CEs types considering the temporal sequences of various hazards from that period and explore their occurrence patterns in China. The results show that 12 CEs types related to extreme hot or dry events widely and frequently (return period < 1 year) occur in China, particularly compound extreme hot-dry-high fire risk events (return period of 0.2–0.4 yrs). Regarding the temporal sequences, MCEs and TCEs have similar spatial distributions, but the magnitudes of MCEs are approximately 1.1 to 2.6 times those of TCEs. This difference is obvious in CEs formed by multiple hazards (>2). By considering occurrence patterns (return period and magnitude), temporal trends, and correlations between different hazards, we determine that the southern humid regions of China are prone to CEs. These results provide a general reference on the national scale for identifying CEs hotspots where more climate action is needed in the future.