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Contrasting moisture evolutions between westerlies‐dominated Central Asia and monsoonal Asia since the mid‐Holocene have been widely recognized. Yet, inconsistent hydrological records over the early Holocene from both regions hamper our understanding of hydroclimatic changes and associated mechanisms. Here we present isotopic and biomarker (alkenone) records from three Chinese lakes located at both regions to address a possible meltwater role in lake water budget. Our results show the occurrence of particularly depleted isotopic values of lake water associated with lake freshening within the deglaciation and early Holocene. Together with anomalously old 14C dates, which were also documented in many other Asian lakes, our observations likely indicate substantial meltwater contribution to mid‐latitude Asian lake water budget, along with the climatic warming. Hence, the potential meltwater effect should be considered when inferring Asian summer monsoon and westerlies behavior over this critical period, with important implications to Holocene hydrological reconstructions and future hydroclimatic projections. Plain Language Summary: Although meltwater events have been well documented in marine records, the effects of meltwater on Asian lake water budget and regional hydrological cycle during the deglaciation and warm early Holocene remain poorly investigated. Our isotopic and biomarker records from Lake Sayram, Yanhaizi, and Qinghai in northern China, together with anomalously old 14C dates from investigated lakes and other Asian lakes, likely indicate substantial meltwater contribution to lake water budget within the deglaciation and early Holocene, which appears to be a large‐scale phenomenon in mid‐latitude Asia. This suggests that the potential meltwater effect on Asian lake hydrology should be assessed in climatic reconstructions and simulations, which may shed light on accurate interpretation of westerlies and summer monsoon circulation over the early Holocene. Key Points: Isotopic records likely indicate meltwater contribution to Asian lake water budget within the deglaciation and early HoloceneAnomalously old 14C dates summarized from mid‐latitude Asian lakes also support substantial meltwater input during this periodMeltwater effects should be considered when inferring early Holocene Asian summer monsoon and westerlies behavior [ABSTRACT FROM AUTHOR]

• Varied lake area was reconstructed over the past ∼500 years in Lake Tuosu. • Westerly-forced Winter-Spring Precipitation controlled lake area changes before 1850. • Mountain-river-basin hydrological system in ACA varied in the industrial era. Investigations of the evolution of naturally and anthropogenically driven hydrology in arid regions are of great significance for hydrological forecasts. Here, we built the past ∼500-year history of lake area and discharge of Lake Tuosu in the northeastern Qaidam Basin. We found that the lake area and inflow variations were sensitive to westerly-forced winter-spring precipitation and showed long-term decreasing trends after 1850. Enhanced local human activities (e.g., agricultural irrigation) led to further rapid shrinkage of Lake Tuosu during 1990–2000, and the lake size reached its minimum in the past 500 years in approximately 2000. Our integrated moisture indices for mountains and basins in southern arid Central Asia showed opposing trends, and the humidity gradient from mountains to basins successively increased after 1850, which may be linked to the migration of the boreal westerlies, global warming, and human activities. After 1950, the humidity increased further, reaching its maximum value in approximately 2000, which likely resulted from the excessive utilization of water resources from anthropogenic activities. Therefore, the mountain-river-basin hydrological system in arid Central Asia has changed significantly, beyond the natural variation pattern, after CE 1950. Therefore, integrated management and rational utilization of water resources are important for ecological protection and sustainable development in the future. [ABSTRACT FROM AUTHOR]

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. • Eolian dust activity of the arid Central Asia was studied using a core of Kuhai Lake. • The HALS-NMF parametric algorithm of end-member analysis was applied. • Siliciclastic materials in the studied core are mainly from eolian contribution. • Eolian dust activity at centennial scale was governed by Siberian High. • Eolian dust activity at decadal scale was governed by total solar irradiance. [ABSTRACT FROM AUTHOR]