Holocene climate development on the central Tibetan Plateau: A sedimentary record from Cuoe Lake

We present a climate record for central Tibet spanning the time between 10500 and 1600 cal years BP from a 5.3-m-long sediment core from Cuoe Lake. The analyses show that high Sr concentration, high TOC content, high C/N ratio and enriched δ13C of lake sediments corresponded to stronger chemical weathering, high productivity, high lake level and warmer/wetter climate and vice versa. As revealed by the variations of these proxies, the climatic evolution during this period can be divided into five stages and several substages. These are a cold/dry stage before 10140 cal years BP, a transition stage from 10140 to 8560 cal years BP, an optimum stage (warm/wet) from 8560 to 5750 cal years BP, a cool/dry stage from 5750 to 4000 cal years BP, a transition stage from 4000 to 3000 cal years BP and a drying-up stage after 3000 cal years BP. These changes are presumably reflections of variations in Indian monsoon intensity which, according to that interpretation, should have been enhanced from 8560 cal years BP, slightly weakened after 5750 cal years BP, and gradually diminished since 3000 cal years BP in this region.