Acta Geographica Sinica ›› 2019, Vol. 74 ›› Issue (7): 1345-1362.doi: 10.11821/dlxb201907006

• Climate Change and Surface Processes • Previous Articles     Next Articles

Environmental variations recorded by chemical element in the sediments of Lake Yamzhog Yumco on the southern Tibetan Plateau over the past 2000 years

GUO Chao1,2,MENG Hongwei3,MA Yuzhen1(),LI Dandan1,HU Caili1,LIU Jierui1,LUO Congwen1,WANG Kai1   

  1. 1.State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
    2.College of Resource Environment and Tourism, Hubei University of Arts and Science, Xiangyang 441053, Hubei, China
    3.School of Tourism and Geographical Sciences, Yunnan Normal University, Kunming 650500, China
  • Received:2018-01-24 Revised:2019-03-11 Online:2019-07-25 Published:2019-07-23
  • Contact: MA Yuzhen
  • Supported by:
    The National Basic Research Program of China(2013CB956001);National Natural Science Foundation of China(41571186);National Natural Science Foundation of China(41330748)


The Tibetan Plateau is sensitive to climate changes induced by interactions of large scale atmospheric circulations, including the East Asian monsoon, Indian monsoon and mid-latitude westerlies. In this paper, we present a high-resolution chemical element dataset covering the past 2000 years from Lake Yamzhog Yumco (28°27′N-29°12′N, 90°08′E-91°45′E, altitude in 4440 m a.s.l.), which is a representative inland lake located in the southern Tibetan Plateau. These data were acquired using an X-ray fluorescence (XRF) core scanner, which is used for in situ, high-resolution, continuous, multi-element analyses. The chronology presented herein is based on 210Pb and AMS 14C dates from the macro-remains of plants. The interpretation of elemental geochemistry, together with magnetic susceptibility and grain-size, enabled the reconstruction of the environmental changes in the southern Tibetan Plateau over the past 2000 years. Reconstructions of the temperatures, precipitation and lake levels indicated that the Medieval Warm Period (MWP) and Current Warm Period (CWP) were associated with low precipitation and high temperatures. In contrast, the Dark Cold Age Period (DCAP) and Little Ice Age (LIA) were associated with high precipitation and low temperatures. Moreover, the level of warmth during the peak of the MWP may equal or slightly exceed the 20th century warming. In addition, the prolonged LIA may have experienced a warm event on a centennial timescale, and the 17th and 18th centuries may be the coldest centuries in the last two millennia. Our reconstructions also indicated that the lake level evolution has been affected by interactions of temperature and precipitation. More specifically, during the cold periods, an increase of precipitation amplified the rise of lake levels, and vice versa. The climate records from Lake Yamzhog Yumco have confirmed a cold-moist/warm-dry climate pattern on the southern Tibetan Plateau over the past 2000 years. Additionally, the temperature variations inferred from the records were strongly correlated with the solar irradiance and northern hemispheric temperature changes, which suggests a possible link between the solar forcing and climate variability in the past 2000 years on the southern Tibetan Plateau. In addition, the enhancement and southward shift of the westerlies was determined to have significantly contributed to the high precipitation conditions during the LIA on the southern Tibetan Plateau.

Key words: elemental chemistry, southern Tibetan Plateau, the past 2000 years, Medieval Warm Period, Little Ice Age, climate change