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Zusammenfassung:
Terrestrial glacial records from the Patagonian Andes and New Zealand Alps docu-
ment quasi-synchronous Southern Hemisphere–wide glacier advances during the late
Quaternary. However, these records are inherently incomplete. Here, we provide a contin-
uous marine record of western–central Patagonian ice sheet (PIS) extent over a complete
glacial–interglacial cycle back into the penultimate glacial (~140 ka). Sediment core
MR16-09 PC03, located at 46°S and ~150 km offshore Chile, received high terrestrial
sediment and meltwater input when the central PIS extended westward. We use biomark-
ers, foraminiferal oxygen isotopes, and major elemental data to reconstruct terrestrial
sediment and freshwater input related to PIS variations. Our sediment record documents
three intervals of general PIS marginal fluctuations, during Marine Isotope Stage (MIS)
6 (140 to 135 ka), MIS 4 (~70 to 60 ka), and late MIS 3 to MIS 2 (~40 to 18 ka). These
higher terrigenous input intervals occurred during sea-level low stands, when the west-
ern PIS covered most of the Chilean fjords, which today retain glaciofluvial sediments.
During these intervals, high-amplitude phases of enhanced sediment supply occur at
millennial timescales, reflecting increased ice discharge most likely due to a growing PIS.
We assign the late MIS 3 to MIS 2 phases and, by inference, older advances to Antarctic
cold stages. We conclude that the increased sediment/meltwater release during Southern
Hemisphere millennial-scale cold phases was likely related to higher precipitation caused
by enhanced westerly winds at the northwestern margin of the PIS. Our records com-
plement terrestrial archives and provide evidence for PIS climate sensitivity
