Paleoclimate Significance of Reconstructed Rainfall Isotope Changes in Asian Monsoon Region

Abstract Speleothem oxygen isotope (δ 18 Oc) records have been regarded as a critical reference to study past Asian monsoon variability. However, existing δ 18 Oc records in the Indian monsoon region are fragmented in time coverage and/or sampling resolution since the last deglaciation. Also, the climatic interpretation of δ 18 Oc is still obscure. Here, we report a continuous and centennial‐resolved leaf wax hydrogen isotope (δD wax ) record over the past ∼28 ka from Lugu Lake in Indian‐monsoon influenced southwestern China. Our new record shows striking consistency with the well‐established δ 18 Oc record in East Asian monsoon‐influenced southeastern China, revealing a spatially coherent change and thus a similar physical process in rainfall isotopes in the broader Asian…