Widespread vulnerable greening of terrestrial vegetation in a warming world

Terrestrial vegetation has continued to green in recent decades under warming and rising atmospheric CO2, yet ecosystem resilience has declined across large portions of the globe. The extent, spatial patterns, and drivers of this emerging decoupling between vegetation greening and resilience remain poorly understood. Here, we assess the dynamics of vegetation greenness and resilience, and disentangle the underlying mechanisms that drive their emerging decoupling using multiple satellite-derived and modelled data. We show that a pervasive pattern of vulnerable greening, characterized by increasing greenness but declining resilience, affects 41.5% of global vegetated land. This pattern is primarily driven by recent changes in temperature and water availability, which exert distinct impacts on vegetation greenness and resilience. Rising temperature generally enhances vegetation greening, but leads to a persistent decline in resilience, especially in tropical and boreal forests. Variability in water availability dominates resilience loss over 23.0-42.1% of vulnerable greening area across vegetation types, whereas its influence on greenness is negligible. Current Earth system models fail to capture the resilience dynamics, yielding systematically underestimated resilience but overly optimistic trends. Our findings reveal a pervasive hidden erosion of ecosystem stability beneath the apparent greening, highlighting growing risks to the terrestrial carbon sink, and the urgent need to better represent vegetation resilience in climate-change assessments.