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New environmental magnetic data from loess and paleosol successions in outcrops in the upper reaches of the Ob River drainage, southern Siberia, track the major climatic variations over the last glacial-interglacial cycle. Profiles of magnetic susceptibility and alternating deposition of loess and soil-formation events correspond to oxygen isotope stages 1-5. The magnetic-susceptibility data, in association with the stratigraphic succession, confirm that the wind-vigor magnetoclimatological model is a viable alternative to the classic pedogenic model. Interpretation of magnetic-susceptibility data from loess-paleosol successions must therefore consider eolian dynamics, available source materials, and transport directions, in addition to pedogenic processes. Rapid magnetic fluctuations are also observed. These are identified-for the first time in Siberian records-as the signature of the abrupt cold pulses responsible for the Heinrich layers in North Atlantic marine sediments. The data thus form a component of climatic teleconnections across the Northern Hemisphere, allowing correlations to be made among (1) Siberian magnetic susceptibility stratigraphy, (2) data recorded from other loess-paleosol successions in China, European Russia, Europe, and North America, (3) North Atlantic ice-rafted detritus, and (4) sea-surface temperatures derived from molecular stratigraphy of marine sediments off the northwest coast of Africa.

Loess-paleosol sequences of the last interglacial-glacial cycle are correlated from European Russia to central Siberia and the Chinese Loess Plateau. During cold periods represented by marine oxygen isotope stages (OIS) 2 and 4, loess deposition dominated in the Russian Plain and the Loess Plateau. In central Siberia, loess deposition took place also, but five to seven thin, weakly developed paleosols are identified in both stages. OIS 3, in the Chinese Loess Plateau near Yangchang, consists of a loess bed that is flanked by two weakly developed paleosols. At Kurtak, Siberia, OIS 3 is represented by two distinct, stacked paleosols with no loess bed separating the paleosols. In the Russian Plain, OIS 3 consists of a single, possibly welded paleosol, representing upper and lower stage-3 climates. Brunisols and Chernozems dominate the profiles in China and Siberia, whereas Regosols, Luvisols, and Chernozems are evident in the northern and southern Russian Plain, respectively. OIS 5 is represented in China and the Russian Plain by pedo complexes in a series of welded soils, whereas in contrast, the Kurtak site consists of six paleosols with interbedded loess. The paleosols consist largely of Brunisols and Chernozems. Although the three areas examined have different climates, geographical settings, and loess source areas, they all had similar climate changes during the last interglacial-glacial cycle. (C) 2003 University of Washington. Published by Elsevier Inc. All rights reserved.