Various proxy records have been used for the understanding of environmental and climate variations during the Holocene. Here, for the first time, we use meteoric 10Be isotope measurements performed on sediments from a drill core collected at the Kunlun Pass (KP) on the northeastern Qinghai-Tibet Plateau (NETP) to investigate hydroclimate changes during the Holocene. The 10Be flux suggests relative low levels in the Early Holocene, followed by a sharp increase to high values at around 4 ka BP (4 ka BP = 4000 years before present). Afterwards, the 10Be flux remains on a high level during the Late Holocene, but decreases slightly towards today. These 10Be deposition patterns are compared to moisture changes in regions dominated by the Indian Summer Monsoon (ISM), East Asian Summer Monsoon (EASM), and the Westerlies. Different from the gradual changes in monsoon patterns, the 10Be data reveal low levels during the Early Holocene until ~4 ka BP when an obvious increase is indicated and a relative high level continues to this day, which is relatively more in agreement with patterns of the Westerlies. This finding provides a new evidence for a shift in the dominant pattern of atmospheric circulation at the KP region from a more monsoonal one to one dominated by the Westerlies. Our results improve the understanding of non-stationary interactions and spatial relevance of the EASM, the ISM and the Westerlies on the Qinghai-Tibet Plateau.
Bibliografisk informationFunding Information:
This work was supported by the National Key R&D Program of China (Grant No. 2016YFC0402710 ); National Natural Science Foundation of China (Grant Nos. 51539003 , 41761134090 , 51979072 , 51709074 ); The Fundamental Research Funds for the Central Universities (Grant No. B200202007 ); National Science Funds for Creative Research Groups of China (Grant No. 51421006 ); Strategic pilot science and technology project of the Chinese Academy of Sciences (Grant No. XDA2010010307 ); The Special Fund of State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering (Grant No. 20195025612 , 20195018812 , 520004412 ); Jiangsu Post-doctoral Research Funding Program (Grant No. 2020Z111 ); A. Aldahan thanks the United Arab Emirates University for financial support through UPAR grants and the Department of Earth Sciences at Uppsala University for 10 Be sample preparation; M. Czymzik acknowledges the German Research Foundation (DFG) for funding through grant CZ 227/4-1 .
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