A High-Resolution Speleothem Record of Marine Isotope Stage 11 as a Natural Analog to Holocene Asian Summer Monsoon Variations

Abstract

A full-spectrum characterization of past interglacial climate is a necessary prerequisite for the detection and attribution of climate changes during the current interglacial. Here we present a speleothem record of Asian summer monsoon (ASM) during Marine Isotope Stage (MIS) 11 interglacial (MIS 11c), from Yongxing cave, China. The record's unprecedented chronologic constraints and decadal-scale temporal resolution allow a precise and direct comparison of ASM between the MIS 11c and the Holocene. Our data suggest that orbital-centennial patterns of ASM were remarkably similar during both interglacial, including their pacing and structure. Notably, a multi-millennial stronger monsoon late in MIS 11c, the “Late-MIS 11c shift,” is similar to the Late Holocene strengthening of the ASM, the “2-Kyr shift.” Thus, the multicentennial ASM weakening at the end of the Late-MIS 11c shift could imply that the current century-long ASM waning trend may persist into the future, if only natural forcings are considered.