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The palaeosol-loess-aeolian sand sequence in the eastern Gonghe Basin, which is located at the convergence of the Asian summer monsoon, winter monsoon and the westerlies, reveals detailed moisture changes in the northeastern Qinghai-Tibetan Plateau (NETP) during the last 17 ka. Analysis of magnetic susceptibility (MS), total organic carbon, carbonate content, grain size and geochemical parameters indicate that the region was dominated by an extremely dry climate during ~17.0-15.82 ka, accompanying large-scale desert expansion in the last glacial maximum (LGM). Subsequently, the climate became generally dry during 15.82-14.6 ka, an interval in which loess rapidly accumulated. Enhanced humidity occurred at 14.6 ka, probably associated with increased strength of the East Asian summer monsoon. The region experienced slightly decreased moisture at around 6.5 and 5.8 ka. After 2.7 ka, the climate became wetter. This interpretation correlates with climatic records from lacustrine and aeolian deposits in the NETP during the LGM, the last deglaciation and the early-middle Holocene. High climatic moisture in the Late Holocene facilitated the formation of a well-developed palaeosol in the NETP. The effective moisture change in the Gonghe Basin is not simply ascribed to the influences of Asian summer monsoons; instead, it was possibly influenced by the interaction of evaporation and monsoonal precipitation forced by solar insolation variation. The balance between these variables was very influential on the effective moisture change in the closed inland basin of the NETP. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The history of climate change and related driving mechanisms of the Gonghe Basin, northeastern Qinghai-Tibetan Plateau, China, was reconstructed in the Holocene epoch, based on the comprehensive analysis of multi-proxies consisting of magnetic susceptibility, grain size, and geochemical elements from eolian and peat deposits at different altitudes. The results indicate that Holocene climate change at different altitudes is both consistent and different: a synchronous record of an increased warm-humid phase (10.0-8.5 ka) and a cold phase around 8.2 ka in the Early Holocene; an optimal warm-humid condition in marginal mountains of the Gonghe Basin in the Mid-Holocene; and a gradual decline in temperature and humidity in the Late Holocene. The Gonghe Basin interior in the Mid-Holocene was relatively arid, with increased moisture in the Late Holocene. On this basis, we compared our results to the paleoclimatic record in the low-latitude Asian monsoonal region, which indicates that, in addition to the Asian summer monsoonal strength having influenced regional climate change, the upward and subsidence motion of airflow over the Qinghai-Tibetan Plateau induced by topographic conditions, evaporation, and the feedback effect by the substrate was also influential. The latter was especially important for spatial-temporal differences in Middle and Late Holocene climatic changes at different altitudes. [ABSTRACT FROM AUTHOR]