Paleoglacial and paleoclimate reconstructions during the global Last Glacial Maximum in the Longriba area, eastern Tibetan Plateau

作     者：YANG Wei-lin HAN Ye-song PENG Xu RAN Ze-ze LIU Qing LIU Geng-nian YANG Wei-lin;HAN Ye-song;PENG Xu;RAN Ze-ze;LIU Qing;LIU Geng-nian

作者机构：College of Urban and Environmental SciencesPeking UniversityBeijing 100871China 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2021年第18卷第2期

页      面：307-322页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 07[理学] 070501[理学-自然地理学] 0303[法学-社会学] 070903[理学-古生物学与地层学(含：古人类学)] 0708[理学-地球物理学] 0818[工学-地质资源与地质工程] 0705[理学-地理学] 0815[工学-水利工程] 0706[理学-大气科学] 0816[工学-测绘科学与技术] 0813[工学-建筑学] 0704[理学-天文学] 0833[工学-城乡规划学] 0713[理学-生态学] 0834[工学-风景园林学（可授工学、农学学位）] 

基　　金：supported by the National Science Foundation of China(NSFC 41771005 and 41230743)。 

主　　题：Ice surface profile ^(10)Be surface exposure dating Paleoglacial reconstruction Paleoclimate reconstruction Global Last Glacial Maximum Eastern Tibetan Plateau 

摘      要：Owing to the remoteness of the Longriba area and the lack of dating records,it is extremely challenging to reconstruct the chronology and extent of the paleoglaciers in this area.In this paper,we combined limited observational data with automated modelling for paleoglacial reconstructions.We first identified a broadly distributed paleoglacier from satellite imagery and field investigation based on the sediment-landform assemblage principle and dated it to 23.1±1.4~19.5±1.2 ka by ^(10)Be exposure dating,corresponding to the global Last Glacial Maximum(gLGM).Then,we reconstructed the extent and ice surface of 171 paleoglaciers formed during the similar period based on geomorphological evidence and‘ice surface profile’modelling.The results showed that the paleoglacial coverage was 426.5 km2,with an ice volume of 38.1 km^(3),in the Longriba area.The reconstructed equilibrium line altitudes(ELAs)based on modelled ice surfaces yielded an average of 4245±66 m above sea level(asl),~725±73 m lower than the present ELA(4970±29 m asl).The temperature was~5.51-6.68℃lower,and the precipitation was~30-34%less in Longriba,during the gLGM compared to the present day.This glacial advance was mainly driven by colder climate that was synchronous with Northern Hemisphere cooling events.