Last deglacial climatic variability in Tibetan Plateau as inferred from n-alkanes in a sediment core from Lake Zabuye

Abstract

The last deglaciation is of great interest because Northern Hemisphere climate has gone through several abrupt changes. Here, we present an n-alkane record of the last deglaciation from the sedimentary sequence of Lake Zabuye in the southwestern Tibetan Plateau. The climatic and environmental variations during the last deglaciation in Lake Zabuye area as inferred from the characteristics of the n-alkanes can be classified into three periods. During the early part of the last deglaciation (23.1–15.6 ka BP), the climate changed from cold-moist to cold-dry condition, algae, bacteria and aquatic plants was prosperous, proportion of herbaceous plants was higher than the woody plants; during Bølling/Allerød period (15.6–12.5 ka BP), all proxies implied warm climatic conditions, woody plants were gradually prosperous; and the Younger Dryas (12.5–11.8 Ka BP) was characterized by cold and wet climate, with algae and bacteria dropped, submerged and floating plants flourished, proportion of woody plants was higher than the herbaceous plants. The alkanes-based climatic reconstruction for Lake Zabuye suggests that the regional climate variability during the last deglaciation was coherent with the classical climate pattern observed in the Northeastern Atlantic implying the existence of a teleconnection between Asian and the North Atlantic climate systems.