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The dynamics of Northern Hemisphere ice sheets during Late Quaternary glacials have yet been dominantly examined from a Laurentide Ice Sheet perspective, which helped shaping the idea of moisture-starved glacials and small-scale ice volume variability. However, the waxing and waning of the European Ice Sheet (EIS) casts doubt on this perception. Understanding EIS dynamics under glacial boundary conditions is crucial because its meltwater pulses influence global climate by weakening deepwater formation in the North Atlantic Ocean. Here we show that the advection of subtropical water toward the continental margin of western Europe lead to enhanced moisture availability on the continent and fueled the growth of EIS lobes during glacials. This warm-water pooling was caused by monsoonally paced enhanced Mediterranean Outflow Water (MOW) entrainment that dragged subtropical surface waters toward the European margin. This mechanism presents a yet unrecognized marine-terrestrial pathway that allows low-latitude forcing to shape high-latitude glaciations. Plain Language Summary The build-up of glacial ice shields required large amounts of atmospheric precipitating as snow. However, under full glacial conditions, cold surface oceans reduce the amount of evaporation, which counteracts the growth of large continental ice shields. Our study aims to unravel the source and transport pathways of moisture that helped to rapidly form the European Ice Shield during the past two glacials. We propose the novel concept that the outflow of dense Mediterranean water into the North Atlantic played a decisive role as it helped to "drag" warm surface waters toward the European Margin by strengthening the Azores Current. This warm, subtropical water current supplied vast amounts of moisture, which then was transported northward into continental Europe and fueled ice sheet growth. The strength of Mediterranean Outflow Water discharge into the Atlantic strongly depends on monsoonal activity in i

Proxy data reveal the existence of episodes of increased deposition of ice-rafted detritus in the North Atlantic Ocean during the last glacial period interpreted as massive iceberg discharges from the Laurentide Ice Sheet. Although these have long been attributed to self-sustained ice sheet oscillations, growing evidence of the crucial role that the ocean plays both for past and future behavior of the cryosphere suggests a climatic control of these ice surges. Here, we present simulations of the last glacial period carried out with a hybrid ice sheet–ice shelf model forced by an oceanic warming index derived from proxy data that accounts for the impact of past ocean circulation changes on ocean temperatures. The model generates a time series of iceberg discharge that closely agrees with ice-rafted debris records over the past 80 ka, indicating that oceanic circulation variations were responsible for the enigmatic ice purges of the last ice age.