Interglacial Mediterranean wetting driven by suppressed Indian Ocean convections

The Mediterranean is widely recognized as a climate change hotspot. The Last Interglacial (~127 ka; LIG) and mid-Holocene (~6 ka; MH), characterized by increased boreal summer insolation and decreased winter insolation, provide valuable opportunities to investigate the Mediterranean climate’s response to global-scale forcings. In agreement with proxy data, multi-model simulations from the Paleoclimate Model Intercomparison Project Phase 4 (PMIP4) show that the Mediterranean experienced wetter conditions during the LIG and MH compared to the pre-industrial period. The simulated wetting is most pronounced in late winter and early spring (February to April), when the circulation anomalies are akin to a negative phase of the North Atlantic Oscillation and the North Atlantic storm tracks shift southward. Standalone atmospheric experiments emphasize the critical role of cooling and suppressed convection over the Indian Ocean, which modulate the North Atlantic climate through atmospheric teleconnections. This physical link between Mediterranean wetting and Indian Ocean drying is consistently reproduced across the inter-model spread during the LIG and might also be one factor in the spread of future climate projections in the Mediterranean.