Millennial‐Scale Temperature Evolution in East Asia During the Last Glacial: Constraints from Speleothem Δ 47 Thermometry

Abstract Millennial‐scale events of the last glaciation profoundly reorganized global climate, yet the terrestrial temperature response in East Asia remains debated due to the seasonal biases and calibration uncertainties inherent in biological proxies. To address this, we present a carbonate clumped isotope (Δ 47 ) record from a central Chinese speleothem spanning the Last Glacial Maximum (LGM) and Heinrich Stadial 1 (HS1). Supported by petrographic and trace element evidence for negligible kinetic effects, our temperature record from the thermally buffered cave provides a robust reconstruction of mean annual temperature. We identify a ∼6°C cooling compared to the present during the LGM, intensified by an additional ∼2°C cooling during HS1. These results contradict warming signals found in precious study but align with iTraCE simulations, which attribute HS1 cooling to severe winter temperature drops partially offset by insolation‐driven summer warming. Our findings reconcile current proxy–model temperature discrepancies and improve the climatic interpretation of speleothem δ 18 O during Heinrich stadials.