The Predominant Compound Extreme Events Inhibiting Vegetation Growth in China During the Past Two Decades

As global climate change intensifies, compound extremes (CEs) have become more frequent and have increased the vulnerability of terrestrial vegetation. While future climate change is expected to continue to exacerbate the severity of CEs, there remains a significant gap in understanding the relative contribution of different CEs to vegetation damage. In other words, there is an urgent need to identify the dominant CE inhibiting vegetation growth. In this study, we focused on six major CE categories over China and examined their spatiotemporal distribution during 2001–2018. We then utilised satellite-derived vegetation index to detect negative extremes of vegetation growth (NEVs) induced by CEs. By quantifying the coincidence rate of CEs with NEVs, we revealed compound dry extremes as the dominant CE event with the highest coincidence with NEVs in 37% vegetated area in China, followed by compound dry-cold extremes (22%). Generally, dry extremes were more likely to pose vegetation damage than wet extremes and climate warming has exacerbated these negative effects. In particular, grassland was more susceptible to compound droughts than shrubland/forest because of its lower resistance to environmental stress. Our findings will enhance the current understanding of CE impacts and serve as a guide for developing long-term strategies to mitigate CE risks under climate change.