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This paper summarizes the work from the INQUA 1997 Project “Response of soilformation to short-warm-episodes of Asian summer monsoon” and its seeded related internationaland domestic grants. It reviews the effects of the millennial monsoonal changes on the loess-paleosols of the Chinese Loess and Tibetan Plateaus. High-resolution proxy records ofpedogenesis and monsoons demonstrate that both Asian winter and summer monsoons wereunstable and synchronously and inversely coupled during the last glaciation. During that timerapid episodic cycles of cold surges and warm enhancements spanned only ca. 1-2 ka in high-frequency domain. Sub-Milankovitch cycles (6-8 ka) of progressive cooling or weakening in low-frequency domain generally resembled the pattern of the North Atlantic climatic change. However,during the last interglacial, Asian winter and summer monsoons seemed to vary independently, theformer being stable and the later unstable. Soil formation seems to occur in surprisingly fastresponse to the summer monsoon warm enhancements, resulting in weakly or moderatelydeveloped paleosol sequences. North Atlantic and polar cold air surges though the westerlies andother paths, and the north-south swing of the westerlies beside the Tibetan Plateau, may be thealternative mechanisms for the rapid monsoonal changes during the last glacial. But in the lastinterglacial, the summer monsoons worked largely independently.
This paper summarizes the work from the INQUA 1997 Project “Response of soilformation to short-warm-episodes of Asian summer monsoon ” and its seeded related internationaland domestic grants. It reviews the effects of the millennial monsoonal changes on the loess-paleosols of the Chinese Loess and Tibetan Plateaus. High-resolution proxy records of pedogenesis and monsoons demonstrate that both Asian winter and summer monsoons wereunstable and synchronously and inversely coupled during the last glaciation. During that timerapid episodic cycles of cold surges and warm enhancements spanned only ca. 1 -2 ka in high-frequency domain. Sub-Milankovitch cycles (6-8 ka) of progressive cooling or weakening in low-frequency domain generally resembled the pattern of the North Atlantic climatic change. However, during the last interglacial, Asian winter and summer monsoons seemed to vary independently, theformer being stable and the later unstable. soil formation seems to occur in surprisingly fastre sponse to the summer monsoon warm enhancements, resulting in weakly or moderately developed air pale surges though the westerlies andother paths, and the north-south swing of the westerlies beside the Tibetan Plateau, may be the alternative mechanisms for the rapid monsoonal changes during the last glacial. But in the lastinterglacial, the summer monsoons worked substantially independently.