Study Reveals a Comprehensive Picture of the Vegetation and Climate on the Tibetan Plateau during the Quaternary
The Tibetan Plateau has long been a focus of geoscientific studies because of its importance in global tectonics and Asian and global climate change across a wide range of timescales. However, little is known of its environmental history through the Quaternary ice ages, which hinders our understanding of the dynamic association between the Tibetan Plateau and large regional- and global-scale environmental changes.
ZHAO Yan's team from the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences drilled a continuous 573-m high-quality lake-sediment core from the Zoige Basin, eastern Tibetan Plateau. They obtained the first high-resolution (~600-yr) record of the vegetation and climate changes at orbital and millennial scales over the last 1.74 million years (Myr).
This study aimed at understanding the evolution of the Quaternary vegetation and climate on the Tibetan Plateau and its links to the interactions of low-latitude insolation and high-latitude ice-volume forcing. This work was recently published in Science Advance.
The results showed that the low-latitude insolation forcing dominated by precession has been driving the evolution of the Tibetan Plateau vegetation and climate over the last 1.74 Myr.
With the progressive increase of global ice-volume, the Tibetan Plateau climate and vegetation can be described by three successive modes, i.e. an insolation-dominated mode (1.74–1.54 Myr), a transitional insolation-ice mode (1.54–0.62 Myr) and an ice-driven mode (the last 0.62 Myr). The influence of North Atlantic millennial-scale variability was established from ~1.54 Myr.
Schematic diagram of the forcings of Zoige basin vegetation and climate change modes at orbital and millennial scales over the past 1.74 Myr(Image by ZHAO Yan’s team)
"The significance of this study lies in filling the data gap of the high-resolution Quaternary record of vegetation and climate changes in the high-altitude monsoonal region of the Tibetan Plateau," said Prof. ZHAO.
"We provided a comprehensive picture of how the interaction of low-latitude insolation and high-latitude ice-volume forcing shaped the evolution of the climate, which is different from the previous inference that the plateau climate is predominantly linked to glacial cycles, and revealed the pervasive influence of the North Atlantic ice-rafting history on the millennial-scale variability during the past 1.54 Myr," she added.
This work was funded by the Major Program of National Natural Science Foundation of China ("Orbital-scale variability and forcing mechanism of the East Asian monsoon") and other research grants.
Reference:
Y. Zhao*, P. C. Tzedakis, Q. Li et al., 2020. Evolution of vegetation and climate variability on the Tibetan Plateau over the past 1.74 million years. Science Advances, 6, eaay6193.Download attachments：
