Abstract Eolian dust activity studies on the arid Central Asia (ACA), one of the world's largest dust sources, are of great importance to the global climatic system. Grain size distributions (GSDs) can provide information on sediment sources, transport processes and sedimentary environments. As a result, GSD is the most frequently applied proxy in reconstruction of past eolian dust activities of the ACA using lake sediments. The GSD dataset for a core spanning the last ~850 years from Kuhai Lake on the northeastern Tibetan Plateau was unmixed by end-member analysis (EMA) for reconstruction of past eolian dust activities on the southeastern margin of the ACA. The results suggest that EM 2 and EM 3, which were added together to form an eolian dust activity proxy, represent the proximal eolian suspension and saltation loads, respectively. The fractional abundances of EMs suggest that siliciclastic materials in the studied core were mainly from eolian contributions. The occurrence of enhanced eolian dust activities within the cold Little Ice Age period together with the GSDs of EM 2 and EM 3 indicate that eolian dust activities on the southeastern margin of the ACA were basically governed by the Siberian High-produced Asian Winter Monsoon over the last millennium. At decadal to centennial scales, enhanced eolian dust activities generally correspond to warm periods with high total solar irradiance (TSI). Increased temperatures as the result of high TSI would have caused larger increases in evaporation than in precipitation, and hence deteriorated vegetation cover and increased dust sources availability.

中文翻译：

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干旱中亚东南缘近 850 年的风成尘活动

摘要 中亚干旱地区（ACA）是世界上最大的沙尘源之一，风成沙尘活动研究对全球气候系统具有重要意义。粒度分布 (GSD) 可以提供有关沉积物来源、运输过程和沉积环境的信息。因此，在使用湖泊沉积物重建 ACA 过去的风尘活动时，GSD 是最常用的代理。来自青藏高原东北部 Kuhai 湖过去 850 年的岩心的 GSD 数据集通过端元分析 (EMA) 未混合，以重建 ACA 东南边缘过去的风尘活动。结果表明，EM 2 和EM 3 加在一起形成了风尘活动代理，分别代表了近端风尘悬浮和跳跃载荷。EMs 的丰度分数表明所研究岩心中的硅质碎屑材料主要来自风积贡献。冷小冰期期间风沙活动增强以及EM 2和EM 3的GSD表明，ACA东南缘的风沙活动基本上受西伯利亚高产亚洲冬季风的控制。上个千年。在十年到百年尺度上，增强的风尘活动通常对应于具有高总太阳辐照度 (TSI) 的温暖时期。高 TSI 导致的温度升高会导致蒸发量的增加大于降水量，因此植被覆盖率下降，沙尘源的可用性增加。