Shift from ice sheet to winter insolation as a control on both wetting and dune stabilization in northern Xinjiang during the Holocene

Knowledge of moisture evolution and dune activity during the Holocene in Arid Central Asia (ACA) is of great importance for understanding long-term variations in water resources and human activity in arid and semi-arid regions at mid-latitudes. However, the presence of temperature-affected records prevents the reconstruction of Holocene moisture evolution in ACA with complied data, leading to the main causal mechanisms remaining controversial. This study compiled 28 high-quality moisture records and 118 optically stimulated luminescence (OSL) data points from the northern Xinjiang area of ACA. Moisture records at low elevations (below ∼1700 m, excluding temperature-affected records) and OSL data in northern Xinjiang reveal that dunes mobilized under arid conditions during the 12–9 ka interval, induced by the remnant ice sheet in the Northern Hemisphere decreasing moisture from the mid-latitude ocean and increasing both near-surface wind intensity and sand supply. In contrast, winter insolation at 45 °N enhanced the boreal westerlies to promote climate wetting and dune stabilization after ∼9 ka in this region. Additionally, increases in the supply of dune sand engendered weak and/or sporadic dune remobilization during the cold intervals from the middle-to-late Holocene in northern Xinjiang. Summer insolation at 45 °N, through meltwater and temperature, further regulated moisture cycling to affect the entire Holocene moisture dynamics in high-elevation areas of northern Xinjiang. Finally, this ongoing warming is expected to further increase meltwater, promoting the rapid development of current oasis agriculture, while the warning is expected to gradually reduce water supply and moisture accelerate from low-to-high-elevation areas by intensive evaporation. Ultimately, this will poses a threat to both the ecological environment and agricultural sustainability in northern Xinjiang.