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The Kyzylkum Desert, as a transition area of different dust source in Central Asia, provides and reserves a large amount of dust transported by different atmospheric circulation systems, affecting Uzbekistan and downwind East Asia. However, there remains very few investigations about sediment sources and control factors of the desert. We hereby first present a provenance study on the Kyzylkum Desert, utilizing detrital zircon U‐Pb ages of samples composed of desert sand, alluvial sediments from Amu Darya River and piedmont of Southwest Tianshan Mountains. The results reveal that the Southwest Tianshan Mountains contribute the majority of the Kyzylkum desert sand, and the river system, dominated by Syr Darya, controls the sediment provenance of the desert. Moreover, little contribution from the Kyzylkum and Nurata segments indicates that wind erosion on the bedrocks is weak. However, the aeolian process is still crucial but deposit and storage of dust are determined by local topography. Plain Language Summary: The Arid Central Asia is commonly considered one of the most important dust sources in the world. The Kyzylkum Desert, located in the center of the multiple dust sources in Central Asia, provides and receives a large amount of dust, affecting Uzbekistan and downwind East Asia. However, research on sediment sources and control factors in the area is under debate. We investigate the potential provenance, spatial variability, and transport patterns of sand in the Kyzylkum Desert using detrital zircon U–Pb geochronology on 10 sediment samples. The results reveal that the Southwest Tianshan Mountains contribute the majority of the Kyzylkum desert sand, however, the proximal provenances also have a significant influence on the formation of the desert. The geomorphologic history shows that, the river system, dominated by Syr Darya, controls the sediment provenance of the Kyzylkum Desert. The wind displays little influence on the rework and recycle process of Kyzylkum Desert, indicated by inhomogeneous composition between northwest and southeast desert. The unmixing model results show evidence of sediments from the Kyzylkum Desert transported to the piedmont areas, but the transport and deposition of dust are primarily controlled by topography. Key Points: Detrital zircon U‐Pb dating indicates that the Southwest Tianshan Mountains are the primary sediment source of the Kyzylkum DesertThe river system controls the sediment provenance of the Kyzylkum DesertTopography determines reserve positions of the aeolian sand and dust from Central Asian deserts [ABSTRACT FROM AUTHOR]

Intrashell oxygen isotope (δ18Os) analyses of terrestrial snails have been carried out over two decades. However, the intraspecies/interspecies differences are not yet well understood. Here, we conducted a high‐resolution intrashell δ18Os study on 43 shells from Cathaica fasciola and Bradybaena ravida, and 1449 δ18Os data were obtained. These large amounts of data demonstrate the reproducibility of intrashell δ18Os. Our results suggest that C. fasciola and B. ravida have similar growing seasons mainly from March to October in the studied region. The ecological habits of the two species could explain the distinctive variations in their δ18Os sequences. Therefore, our study may interpret the discrepancy between the studies of land snail species and the stable/clumped isotopes of their shells. Moreover, the calculated average growth rate is ∼290 μm/day (from 250 to 330 μm/day) for nonadult C. fasciola. Thus, the use of snail shells for reconstructing high‐resolution terrestrial climate changes is promising. Plain Language Summary: Land snails are sensitive to climatic and environmental changes. Therefore, the oxygen isotopic composition of snail shells (δ18Os) has often been used to study environmental changes. Researchers started to collect multiple samples from a single shell for δ18Os analyses about two decades ago. However, it is still unclear whether high‐resolution intrashell δ18Os results are repeatable and whether the influences of different individuals/species may exist. To address these issues, we collected 43 snail shells from Cathaica fasciola and Bradybaena ravida. In total, 1449 δ18Os data were obtained. The large amount of data showing similar variations in the intrashell δ18Os from different shells demonstrates the repeatability. Accordingly, our data suggest that the two species have similar growing seasons, mainly from March to October, although their ecological habits are different. In addition, the ecological habits of these two species could explain the subtle differences in their δ18Os. Taken together, our study could resolve the discrepancy between previous work on land snail species and stable/clumped isotopes. Furthermore, the estimated average growth rate is ∼290 μm/day (from 250 to 330 μm/day) for nonadult C. fasciola. Overall, snail shells are promising records for exploring high‐resolution terrestrial climate changes in the future. Key Points: The intrashell δ18Os of land snails is reproducible, which mainly records the δ18O of precipitationCathaica fasciola and Bradybaena ravida have different ecological habits but similar growing seasonEcological habits could explain the discrepancy between studies of land snail species and stable/clumped isotopes [ABSTRACT FROM AUTHOR]

Rationale: Embedding resins are widely used to fix carbonates for high‐precision sample preparation and high‐resolution sampling. However, these embedding materials are difficult to remove after sample preparation and are known to affect the accuracy of carbonate stable isotope analyses. Nevertheless, their impact on clumped isotope analysis, which is particularly sensitive to contamination artifacts, has so far not been tested. The observation that running resin‐containing samples decreased the reproducibility of clumped isotope values for internal laboratory carbonate standards and increased the external standard deviation (SD 0.061–0.088‰) compared to the long‐term observations (0.034‰), prompted us to set up an experiment to test the influence of resin addition on instrument performance. Methods: Here we analyzed the stable and clumped isotope composition of a pure calcium carbonate standard (ETH‐4) mixed with three types of embedding resins in 2:1 and 1:1 proportions. Our aim was to assess how resin addition affects isotope analyses. Results: We found that none of the stable isotopic values were significantly different. The δ13C values were −10.22 ± 0.07‰ (mean ± SD) for pure ETH‐4, while the δ13C values of ETH‐4 mixed with embedding resins in 2:1 and 1:1 proportions were −10.21 ± 0.06‰ and −10.18 ± 0.06‰, respectively (p > 0.05). The δ18O values were −18.82 ± 0.11‰ for pure ETH‐4 versus −18.81 ± 0.09‰ and −18.82 ± 0.08‰ for 2:1 and 1:1 ETH‐4:resin mixtures, respectively (p > 0.05). Given the large uncertainty in our results, we did not find significant differences between different mixtures in the carbonate clumped isotope values (Δ47), with 0.458 ± 0.107‰, 0.464 ± 0.086‰, and 0.417 ± 0.089‰ in pure ETH‐4 and ETH‐4 with 2:1 and 1:1 resin mixtures, respectively (p > 0.05). However, a resin‐related bias in the results might be masked by the large uncertainty. The measured ETH‐4 values in our study are similar to the InterCarb values (δ13C = −10.20‰, δ18O = −18.81‰, Δ47 = 0.450‰, InterCarb‐Carbon Dioxide Equilibrium Scale). However, the external SD of Δ47 in sessions measuring ETH‐4 with resins is higher than in sessions without deliberate resin addition for the same measuring period. Conclusions: We find that the potential contamination from the resin addition leads to a larger variability for Δ47 values in sessions measuring ETH‐4 including resins. We therefore recommend purification of embedded samples using a contamination trap with Porapak prior to analysis, if possible, or avoiding resins during sample preparation and workup, as well as monitoring the measurement quality during and after sessions with samples containing embedding resins. [ABSTRACT FROM AUTHOR]

We collected 143 loess optically stimulated luminescence (OSL) ages between 10 ka and 30 ka from Central Asia (CA), and analyzed their probability density functions (PDFs). The PDFs show dust accumulation was greater during the late Last Glacial Maximum (LGM) (23–19 ka) than that during the early LGM (26.5–23 ka). The temporal variability of dust accumulation of CA loess is generally similar to that of Chinese Loess Plateau (CLP) loess, following precession. In contrast, dust accumulation in Greenland was stronger during the early LGM than that during the late LGM, following obliquity. Supported by numerical modeling experiments and our newly dating OSL ages, we conclude dust accumulation in CA and CLP during the LGM was controlled by Siberian High forced by precession, while dust accumulation in Greenland was closely related to both intensity of summer westerlies forced by obliquity, and to intensity of dust emissions at source forced by precession. Plain Language Summary: The dust accumulation in ice cores is often regarded as a direct record of the changing atmospheric dust loading reflecting the aridity of dust source regions. However, the underlying mechanism has not been well understood due to the lack of evidence from dust source regions. Here, we collected 143 optically stimulated luminescence (OSL) ages between 10 ka (ka means 1,000 years) to 30 ka from Central Asia (CA) loess to build the probability density functions (PDFs). The PDFs revealed a stronger dust accumulation occurred during the late LGM than that during the early LGM. The variation pattern of dust accumulation of CA loess is generally similar to that of the Chinese Loess Plateau (CLP) loess, in phase with precession. In contrast, Greenland presents that stronger dust accumulation occurred during the early LGM rather than during the late LGM. The variation pattern of dust accumulation during the LGM in Greenland followed obliquity. Supported by numerical modeling experiment and our newly dating OSL ages, we assumed dust accumulation during the LGM in the CA and CLP was controlled by the Siberian High forced by precession. In contrast, dust accumulation in Greenland was closely related to both the intensity of summer westerlies forced by obliquity and dust emission driven by Siberian High forced by precession. Key Points: Asynchronous variations of dust accumulation at midlatitude Asia and Greenland during the Last Glacial Maximum (LGM)Dust accumulation in Asia during the LGM was controlled by Siberian High forced by precessionDust accumulation in Greenland is related to westerlies forced by obliquity and source dust emissions forced by precession [ABSTRACT FROM AUTHOR]

• δ13C of minute land snail shell could record the local vegetation signals. • Shell δ13C has the potential to be a reliable precipitation proxy. • Spatially scattered shell δ18O reflects the dominant control of precipitation δ18O. Land snails are abundant and well preserved in loess-paleosol sequences on the Chinese Loess Plateau (CLP) and are often regarded as valuable climatic indicators in paleoclimate reconstruction. To date, many stable isotope investigations have been carried out on land snail shells (e.g., δ13C shell and δ18O shell) from diverse geographical and climatic regions. However, few studies have been conducted on modern minute land snails (2–10 mm) on the CLP, and their climatic significance has not been adequately understood. Here, we present new δ13C shell and δ18O shell data from four minute modern land snails (Pupilla aeoli , Gastrocopta armigerella , Opeas striatissimum , Vallonia tenera), and analyses of their correlations with climatic factors (growing season temperature, precipitation and relative humidity) were conducted to examine their climatic significance across the CLP. The results show that δ13C shell can record local vegetation information and has the potential to be a reliable precipitation proxy. Interestingly, δ18O shell exhibits spatially scattered values in the studied region, and these data yielded poor correlations with various climatic parameters, such as precipitation amount, temperature and relative humidity. Given the similar spatial characteristics of observed precipitation δ18O (δ18O p), these phenomena may support the dominant control of δ18O p on δ18O shell. [ABSTRACT FROM AUTHOR]

Lake Qinghai is sensitive to climatic changes because of its pivotal location between mid-latitude Westerlies and the low-latitude East Asian monsoon. An 18.6 m long drilling core (1Fs) from Lake Qinghai provides new information on the hydroclimatic dynamics since the last glacial period. Here, we present the results of bulk mineral assemblages of this core. X-ray diffraction (XRD) results showed that the bulk minerals of the core sediments consist of major clastic minerals (e.g., quartz, feldspar, muscovite), carbonates (e.g., calcite, aragonite, dolomite), and minor clay minerals (e.g., chlorite). Quartz as an exogenous detrital mineral in lake sediments, its abundance is related to lake level changes resulting from regional climate changes via fluvial/aeolian transportation. Aragonite was precipitated from water solutions or chemical alteration of pre-existing minerals or biogenic mediation, closely related to lake hydroclimate change. Mineral assemblages revealed remarkable stepwise hydroclimatic changes. High quartz content and low calcite without aragonite suggested a cold-wet climate condition under predominant westerlies during the last glacial period from 35 to 25.3 ka. Afterward, quartz decreased and aragonite occasionally appeared, indicating an unstable hydroclimatic condition during the last deglaciation. Since the Early Holocene (11.9–8.2 ka), predominant minerals shifted from terrigenous quartz to authigenic carbonates, suggesting an increasing lake level, possibly due to intensified Asian summer monsoon with increased effective moisture. Aragonite became the primary carbonate mineral, implying a warming and humid hydroclimate environment with a relatively higher lake-level. During the Middle Holocene (8.2–4.2 ka), aragonite showed a decreasing trend indicating a higher lake level with weak evaporation. During the Late Holocene since 4.2 ka, there were lower quartz and aragonite, suggesting a deep lake with a weak summer monsoon. Our quartz and carbonate minerals record provided essential clues to reconstruct hydroclimate change in Lake Qinghai since the last glacial period. [ABSTRACT FROM AUTHOR]

The climate instability (millennial-scale rapid climatic oscillations) during the last glacial period has been a hot issue in Quaternary paleoclimate cycle, however, the driving mechanism and involved areas are still unclear. Previous reports mainly came from Green ice cores, North Atlantic deep-sea sediments and loess, stalagmites, lake records in the East Asian monsoon area, however, evidences from the Asian interior arid regions are scarce. Central Asia is distant from oceanic moisture sources and the climate is dominated by the Westerlies and the Subtropical High. Late Pleistocene loess sediments sporadically distributed at the pediments, terraces and basins provide us an opportunity to verify the existence of millennial-scale climatic fluctuations in Central Asia and understand the relations between high-low latitude climate. During the last decades, we have carried lots of loess investigations in Central Asian mainly around the Tienshan Mountains including Xinjiang in China, Kazakhstan, Kyrgyzstan and Tajikistan. In this paper, we report the preliminary results of loess investigations, and divide the loess distribution in Central Asia into three zones, which correspond to different hydrothermal combination conditions; and coupled with previous literatures, we review the progress of paleoclimate study of loess especially chronology in Central Asia, analyze problems of the last glacial climate events in Central Asia, and discusses its process and mechanism. Up to now, paleoclimatic proxies like grain size, mineralogy and geochemistry confirmed that that there are indeed millennial-scale rapid oscillations during the last glacial period in Central Asia, but they are inconsistent in age and variability. These rapid changes may be related to the following aspects: (a) contraction and expansion of the ice sheet in the high latitudes region of North Atlantic, (b) changes in the intensity and extent of the Siberian high pressure which further lead to the variance in wind dynamics, (c) and the north-south migration of the mid-latitude westerlies. The solar radiation is not the main driving factor for the rapid changes in Central Asia. [ABSTRACT FROM AUTHOR]