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▪ Abstract  This paper presents a general review of the recent research advances of the East Asian paleomonsoon, based mainly on studies of the loess-soil sequences in the Chinese Loess Plateau. In the last 2.6 million years, the paleomonsoonal history may be divided into about 166 events on a time scale of the Earth's orbital variations. During the last glacial period, millenial-scale oscillations of the monsoon system were prominent, which can be fairly well correlated with the Dansgaard-Oeschger cycles recognized in the Greenland ice cores. The monsoonal rainfall belt has experienced a wide, repeated advance-retreat change during the glacial-interglacial cycles of the Pleistocene. Both temporal and spatial changes of the monsoon system in the Quaternary could have been linked closely to global ice-volume variations.

Particle-size measurements of some typical loess-soil samples taken in different localities of the Chinese Loess Plateau demonstrate that the grain size ratio of <2 μm/>10 μm (%) can be used as an indicator of variations in intensity of the East Asian winter monsoon winds. Grain-size curves of the Baoji and Weinan sections show that this proxy indicator is very sensitive to loess-soil alterations. Analytical results also suggest that during soil-forming periods, eolian dust accumulation was still substantial and, hence, loess deposition can be regarded as a nearly continuous process during the Quaternary period. In this study we compared the Baoji grain-size time series with the SPECMAP marine isotope record with the objective of elucidating the dynamic linkage between changes in global ice volume and the winter monsoon circulation. Both records show good agreement at both time and frequency domains. In particular, the winter monsoon variations are also dominated by a 100,000 yr period over the past 800,000 yr. It is thus inferred that direct local insolation forcing could be less important in driving the East Asian winter monsoon variability, and, alternatively, variations in glacial-age boundary conditions may have played a key role in modulating and pacing its strength and timing.

The age of Chinese loess deposits has long been disputed. Biostratigraphical and earlier magnetostratigraphical investigations placed the entire loess formation within the Pleistocene and ascertained a maximum loess age of about 1.2 Myr. A new collection of nearly 500 samples from a natural outcrop and a borehole section near Lochuan (lat. 35.8 O N , long. 109.2"E; Shaanxi province) has been dated by magnetic stratigraphy. Thermal cleaning of the natural remanent magnetization (NRM) removes a strong secondary component of viscous origin along the present geomagnetic field which resides largely in magnetite. The characteristic NRM component is due to haematite which is thought to be of chemical origin. Rhythmical intensity variations of NRM and initial susceptibility depend on the loess lithology and may reflect climatic changes during loess deposition.The palaeomagnetic results are consistent between the two sections and yield a clearly defined magnetic polarity zonation. The Brunhes-Matuyama boundary and the Jaramillo subchron have been positively identified in both outcrops at exactly the same stratigraphic level. The Olduvai subchron has been found in the borehole section which records the entire loess sequence. Most probably the formation of Chinese loess began shortly after the Matuyama-Gauss polarity transition. Therefore a late Pliocene age of about 2.4 Myr is assigned to the oldest loess sediments measured.

A 2650‐year (BC665‐AD1985) warm season (MJJA: May, June, July, August) temperature reconstruction is derived from a correlation between thickness variations in annual layers of a stalagmite from Shihua Cave, Beijing, China and instrumental meteorological records. Observations of soil CO2 and drip water suggest that the temperature signal is amplified by the soil‐organism‐CO2 system and recorded by the annual layer series. Our reconstruction reveals that centennial‐scale rapid warming occurred repeatedly following multicentenial cooling trends during the last millennia. These results correlate with different records from the Northern Hemisphere, indicating that the periodic alternation between cool and warm periods on a sub‐millennial scale had a sub‐hemispherical influence.