Quantifying Southern Hemisphere dust sources during the Last Glacial-Interglacial Transition using rare earth elements in the EPICA Dome C ice core

Dust deposits in ice cores provide a valuable archive of past atmospheric circulation, offering insights into climate dynamics during key climate transitions such as the last glacial termination. Here, we present a novel high-resolution reconstruction of dust provenance in the EPICA Dome C (EDC) ice core from 33.7 to 2.8 kyr BP, based on Rare Earth Element (REE) patterns. Using a statistical unmixing algorithm on 279 samples, we quantify, for the first time, contributions from key Southern Hemisphere dust sources. During the late Marine Isotope Stage 3 (MIS3), the Last Glacial Maximum (LGM) and Heinrich Stadial 1 (HS1), dust at EDC was dominated by Patagonian sources, ∼ 65 %–75 % of total deposition, with secondary inputs from Australia (∼ 9 %–11 %), Southern Africa (∼ 5 %–9 %), New Zealand (∼ 6 %–14 %), and Puna-Altiplano (∼ 2 %–4 %). After ∼ 14.5 kyr BP, and especially during the Holocene, the dust assemblage shifted toward greater contributions from low-latitude sources including Australia (21 %–28 %), Southern Africa (∼ 8 %–9 %), and the Puna-Altiplano (∼ 8 %–9 %) – while the Patagonian contribution decreased to an average of ∼ 43 %–53 %, New Zealand (∼ 4 %–10 %) – and source compositions became more variable. This transition in dust provenance contribution is supported by our modeled Sr-Nd isotope composition of EDC dust, which also aligns with changes observed in other East Antarctic ice cores. Comparison with the EDML ice core provenance record reveals overall agreement in major sources and timing of the shifts but also highlights regional variations in the secondary contributions, with EDC showing more consistent inputs from Australia and EDML from Southern Africa. The coherence of the provenance shift recorded at EDC and EDML ice cores points to a common large-scale control, in line with the influence of eustatic sea-level rise and postglacial reorganization of fluvial sediment routing and availability in southern South America.