Millennial-scale climatic oscillations during the last interglaciation in central China

Abstract

Repeated southward excursions of North Atlantic polar water during the last interglaciation (δ 18 O stage 5, 130‐74 ka) are recorded by planktonic foraminifera and ice-rafted detritus in North Atlantic sediment cores, and Greenland ice-sheet cores display quasi-synchronous fluctuations. Comparable high-frequency variations in the East Asian winter monsoon climate are discernible in three loess-paleosol profiles in central China that span the last interglaciation. Peak values of the >40 μm quartz fraction and bulk sediment samples from the S1 (last-interglacial) accretionary paleosol complex reflect major dust-flux events when winter monsoon winds strengthened. Frequent oscillations of the dust flux and nine significant dust events are recorded. Six events, falling between ca. 110 and 70 ka, are correlated with cold peaks (C19‐24) identified in North Atlantic cores. Two comparable dust peaks occur within paleosol S1SS3 (= substage 5e); the older of these, dating to ca. 121 ka, may correlate with a brief cold event recently recognized in high-resolution marine and terrestrial climate-proxy records.