Indian summer monsoon variations during the Younger Dryas as revealed by a laminated stalagmite record from the Tibetan Plateau

High-resolution and precisely dated hydroclimate records in the southeastern Tibetan Plateau (TP) remain sparse beyond the Holocene, which hampers our ability to understand the hydroclimate variability in this important Indian summer monsoon (ISM) fringe area and its global teleconnection. Here we present 3-y resolution delta O-18 and delta C-13 records from a laminated stalagmite (RG-3) from Rige Cave in the southeastern TP, spanning the Younger Dryas (YD). The records allow us to precisely characterize the timing, structure, and particularly centennial-scale events within the YD, and probe the control factors of precipitation delta O-18 ( delta O-18(p)) in the ISM fringe area. On centennial-millennial timescales, the Rige delta O-18 record shows coherent pattern with the East Asian summer monsoon (EASM) counterpart, combined with modeled delta O-18(p) results and spatial analysis, suggesting that delta O-18(p) in this part of the TP is largely controlled by the large-scale atmosphere circulation (or the ISM strength), and the altitude increase in the TP may not potentially result in an opposite delta O-18(p) pattern at least in the monsoonal TP regime. We also found significant delta C-13-delta O-18 covariation on the centennial timescale, suggesting a coincided ISM rainfall and biomass change during the YD. In the Rige records, one weak centennial-scale ISM event (namely the intra-Allerod cold period, [ACP) and three strong centennial-scale ISM events within the YD (namely A1'-A2'-A3') were prominent and occurred between similar to 12,470 and 12,310 +/- 14, similar to 12,210 -12,090 +/- 12 and similar to 12,010-11,920 +/- 12 y BP (before present, where present = 1950 CE), respectively. Spectral analyses of Rige records also revealed a significant similar to 200-y periodicity, which is nearly in-phase with observed centennial-scale variations of the North Atlantic temperature and mid-latitude westerlyjet during that time. These observations support the hypothesis that the solar de Vries cycle (207-y) triggered the centennial-scale climate variations in high northern latitude, leading to the ISM variations via fast atmospheric processes. (C) 2022 Elsevier Ltd. All rights reserved