Abrupt climate fluctuations in Tibet as imprints of multiple meltwater events during the early to mid-Holocene

Abstract

Understanding the impact of meltwater discharge during the final stage of the Laurentide Ice Sheet (LIS) has important implications for predicting sea level rise and climate change. Here we present a high-resolution ice-core isotopic record from the central Tibetan Plateau (TP), where the climate is sensitive to the meltwater forcing, and explore possible signals of the climate response to potential LIS meltwater discharges in the early to mid-Holocene. The record shows four abrupt large fluctuations during the 7–9 ka BP (kiloannum before present), reflecting large shifts of the mid-latitude westerlies and the Indian summer monsoon (ISM) over this period, and they corresponded to possible LIS freshwater events documented in other paleoclimate records. Our study suggests that multiple rapid meltwater discharge events might have occurred during the final stage of LIS. The finding implies the possibility of rapid sea level rise and unstable climate in the transition zone between the mid-latitude westerlies and the ISM due to fast polar ice retreat under the anthropogenic global warming.