Climate change inferred from a fluvial‐lacustrine profile during the Last Deglaciation in the Mu Us Desert, China

Abstract

The Mu Us Desert, located at the edge of the monsoon region, has long been an ideal location for investigating Late Quaternary paleo‐climate and paleo‐environment changes. However, due to the difficulty in obtaining suitable sedimentary profiles, dedicated studies on climate change during the Last Deglaciation remain scarce. This study focuses on a newly excavated fluvial‐lacustrine profile (FHCM) at the southeastern margin of the Mu Us Desert, China. The profile preserves sedimentary strata from the entire Last Deglaciation. By analyzing AMS¹⁴C dating results and environmental indicators including grain size, chromaticity, loss on ignition (LOI), and geochemical element content, the climate evolution patterns of the Mu Us Desert during the Last Deglaciation (19–12 ka BP) were reconstructed. The results show that: (i) The climate changes in the Mu Us Desert during the Last Deglaciation can be divided into three periods: a period of frequent dry-wet and cold-warm climate fluctuations (19.4–16.8 ka BP), a cold-dry climate period (16.8–14.5 ka BP), and a warm-wet climate period (14.5–12.8 ka BP). (ii) The FHCM profile has recorded at least six climatic cycles. End-member analysis of the profile reveals at least two different transport mechanisms in the study area. (iii) The FHCM profile exhibits distinct signals of climatic events, including Heinrich Stadial 1 (HS1) and Bølling/Allerød (B/A) interstadial, demonstrating that the climate evolution of the Mu Us Desert was influenced by the coupled effects of the East Asian Monsoon dynamics, ice-sheet expansion/retreat cycles, and Atlantic Meridional Overturning Circulation (AMOC) oscillations. This study provides crucial evidence for high-resolution paleoclimate reconstructions in monsoon-marginal zones and advances the mechanistic understanding of global-regional climate coupling dynamics.