Latitudinal Expansion of the Holocene Optimum in the East Asian Monsoon Region

Xin Zhou1, Li-Guang Sun1, Tao Zhan2, Wen Huang3, Xinying Zhou4, Qingzhen Hao5, Xiaoqing He1, Chao Zhao6, Jun Zhang2, Yansong Qiao7, Junyi Ge8, Pei Yan1, Da Shao1, Zhuding Chu1 and Wenqing Yang9, (1)USTC University of Science and Technology of China, Hefei, China, (2)The Second Hydrogeology and Engineering Geology Prospecting Institute of Heilongjiang Province, Heilongjiang, China, (3)Guangxi University, Nanning, China, (4)Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China, (5)Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China, (6)Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, China, (7)Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing, China, (8)Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijng, China, (9)USTC University of Science and Technology of China, Institute of Polar Environment, School of Earth and Space Sciences, Hefei, China
Abstract:
With increasingly abundant high resolution and high precision records of East Asian monsoon, its spatial and temporal dynamics during the Holocene have been extensively studied. However, partly due to the lack of records in high latitude areas and the age uncertainties, these studies characterized a wide range of spatial-temporal patterns of Holocene Optimum (HO). We reconstructed a 14,000-year record of vegetation using sediments from a crater lake in Northeast China. Analyses of the vegetation time series show that HO began around 6,000 a BP in Northeast China, significantly later than generally recognized. By comparison with Holocene records of vegetation in other regions of the East Asia, we found a marked northward shift of initial time of HO from 10,600 a BP in South China to 6,000 a BP in Northeast China, which appeared to be forced by the shrinkage of the northern hemisphere ice-sheet (NHIS) during early to mid Holocene. Finally, we fitted a regression model of initial HO time on latitude, which allows us to make prediction of initial HO time based on their geographical locations. This study reveals a strong relationship between latitude and initial HO times and provides a window towards understanding the joint forcing of high and low latitude factors on regional climate.
Back to: The East Asian Monsoon and Its Impact on Marginal Seas: Marine and Terrestrial Records, Modeling, and Observations I