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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. 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. 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 Detrital zircon U‐Pb dating indicates that the Southwest Tianshan Mountains are the primary sediment source of the Kyzylkum Desert The river system controls the sediment provenance of the Kyzylkum Desert Topography determines reserve positions of the aeolian sand and dust from Central Asian deserts

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 δ18Osstudy on 43 shells from Cathaica fasciolaand Bradybaena ravida, and 1449 δ18Osdata were obtained. These large amounts of data demonstrate the reproducibility of intrashell δ18Os. Our results suggest that C. fasciolaand B. ravidahave 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 δ18Ossequences. 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. 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 δ18Osanalyses about two decades ago. However, it is still unclear whether high‐resolution intrashell δ18Osresults are repeatable and whether the influences of different individuals/species may exist. To address these issues, we collected 43 snail shells from Cathaica fasciolaand Bradybaena ravida. In total, 1449 δ18Osdata were obtained. The large amount of data showing similar variations in the intrashell δ18Osfrom 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. The intrashell δ18Osof land snails is reproducible, which mainly records the δ18O of precipitationCathaica fasciolaand Bradybaena ravidahave different ecological habits but similar growing seasonEcological habits could explain the discrepancy between studies of land snail species and stable/clumped isotopes The intrashell δ18Osof land snails is reproducible, which mainly records the δ18O of precipitation Cathaica fasciolaand Bradybaena ravidahave different ecological habits but similar growing season Ecological habits could explain the discrepancy between studies of land snail species and stable/clumped isotopes

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. 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. 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 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 precession Dust accumulation in Greenland is related to westerlies forced by obliquity and source dust emissions forced by precession