Holocene ocean-atmosphere coupling and Mediterranean sensitivity to Atlantic circulation: Lessons from the Late...

Climate variability has profoundly influenced societies in the semiarid Eastern Mediterranean. Proxy records indicate progressive mid-Holocene drying culminating in severe droughts ∼1250 BCE, coincident with the Late Bronze Age collapse (1300 to 900 BCE). Using the EC-Earth3-Tr8K transient Holocene simulation, we reconstruct regional hydroclimate evolution and its underlying mechanisms. The model reproduces a gradual orbitally driven aridification, spatially heterogeneous across the region, with persistent drying in the Levant but enhanced effective moisture in parts of the Balkans and Anatolia due to cooling-induced evapotranspiration decline. Superimposed on this long-term trend are extreme drought events, which arise from the alignment of Atlantic internal variability across centennial to millennial timescales, amplifying drying on an already arid background state. These results provide model-based evidence of how evolving amplitude and phase structure of Atlantic internal variability reshaped Eastern Mediterranean hydroclimate through the mid-to-late Holocene. We demonstrate that oceanic variability can manifest as abrupt regional crises when ecological and societal thresholds are crossed.