Climate models project increasing frequency and intensity of droughts in the Mediterranean Basin, escalating the threat to ecosystems. Exceptionally dry periods can significantly reduce ecosystem productivity and functioning, eventually leading to dieback. Understanding the effect of individual drought attributes on ecosystem resilience is crucial, particularly for the Mediterranean Basin, a biodiversity and climate change hotspot.  

We employed an event-based approach to drought regime analysis across several ecoregions in the basin over the 2001–2018 period. Droughts were detected using the Standardized Precipitation-Evapotranspiration Index, estimated from CHELSA products, and vegetation response was evaluated using the kernel Normalized Difference Vegetation Index from MODIS data. We measured severity, duration, intensity, time since the last drought, and severity legacy as drought attributes. We evaluated vegetation resilience to droughts by extracting the temporal components of resistance and recovery and analyzing their trends over changing drought regimes and attributes. 

Classifying droughts by severity quartiles, we observed that most ecoregions maintained their resilience levels across varying drought regimes. Some arid ecoregions displayed reduced resilience under the most severe drought class, associated with a larger response magnitude compared to more humid areas. Drought duration emerged as the strongest driver of the resistance component across different ecosystems, with longer durations associated with reduced resistance, while the recovery component was more influenced by the characteristics of previous droughts, with high variability across ecoregions. These results highlight that the adaptation to water scarcity of arid ecosystems does not necessarily imply their resilience to droughts and support the identification of vulnerable regions under projected drought regime shifts.