Joint insolation and ice sheet/CO_(2)forcing on northern China precipitation during Pliocene warmth  

太阳辐射与冰盖/CO^(2)驱动晚上新世暖期中国北方降水

作　　者：Zeng Luo Junsheng Nie Annelisa Ehret Moe Richard V.Heermance Carmala Garzione Timothy D.Herbert Zhao Wang Hua Li Rui Zhang Xiangming Zhao Ulrich Salzmann 罗增;聂军胜;Annelisa Ehret Moe;Richard V.Heermance;Carmala Garzione;Timothy D.Herbert;王钊;李华;张蕊;赵向明;Ulrich Salzmann(Key Laboratory of Western China's Environment System(Ministry of Education),Lanzhou University,Lanzhou 730000,China;Center for Excellence in Tibetan Plateau Earth Sciences,Chinese Academy of Sciences,Beijing 100101,China;Department of Geological Sciences.California State University,Northridge 91330-8266,USA;Department of Environmental Sciences,Rochester Institute of Technology,Rochester 14623,USA;Department of Earth,Environmental,and Planetary Sciences,Brown University,Providence 02912,USA;Department of Chemistry,Lanzhou University,Lanzhou 730000,China;School of Geography,Geomatics and Planning,Jiangsu Normal University,Xuzhou 221116,China;Department of Geography and Environmental Sciences,Northumbria University,Newcastle Upon Tyne NE18ST,UK)

机构地区：[1]Key Laboratory of Western China's Environment System(Ministry of Education),Lanzhou University,Lanzhou 730000,China [2]Center for Excellence in Tibetan Plateau Earth Sciences,Chinese Academy of Sciences,Beijing 100101,China [3]Department of Geological Sciences,California State University,Northridge 91330-8266,USA [4]Department of Environmental Sciences,Rochester Institute of Technology,Rochester 14623,USA [5]Department of Earth,Environmental,and Planetary Sciences,Brown University,Providence 02912,USA [6]Department of Chemistry,Lanzhou University,Lanzhou 730000,China [7]School of Geography,Geomatics and Planning,Jiangsu Normal University,Xuzhou 221116,China [8]Department of Geography and Environmental Sciences,Northumbria University,Newcastle Upon Tyne NE18ST,UK

出　　处：《Science Bulletin》2021年第4期319-322,M0003,共5页科学通报（英文版）

基　　金：supported by the Second Tibetan Plateau Scientific Expedition(2019QZKK0704);the National Natural Science Foundation of China(42030505 and 41672157);the State Scholarship Fund organized by the China Scholarship Council(CSC)in 2018,the Royal Society(IE 141128);the U.S.National Science Foundation(1348005,1348075,and 1545859)。

摘　　要：East Asian summer monsoon(EASM)precipitation affects the lives of billions of people and impacts the stability of fragile desert ecosystems in central Asia[1].Therefore,many studies have focused on understanding the variability of the EASM and its relationship with insolation,ice sheet,and C0_(2)forcings[1-3].Evidence for EASM variability is preserved in the eolian dust sequences on the Chinese Loess Plateau(CLP),which highlight the importance of Northern Hemisphere(NH)ice sheets,C0_(2)levels,and insolation in controlling the strength of the EASM during the Quaternary[2].In contrast,Pliocene(5.3-2.6 Ma)proxy records of the EASM from the CLP reveal weak orbital signals,suggesting weak sensitivity to ice sheets,C0_(2)levels,and insolation forcing during this sustained warm period[4].These Pliocene proxy records also contrast model simulations which suggest high sensitivity of the EASM to orbital forcing(particularly precession)during this time[5].理解未来东亚夏季风的变化要求查明地质历史时期中的气候温暖阶段东亚夏季风的变化及驱动机制.黄土高原的风成沉积序列是研究过去东亚季风变化的良好载体,对第四纪期间沉积的记录研究表明东亚夏季风在此期间可能主要受冰盖、CO_(2)和太阳辐射的共同驱动.晚上新世暖期(3.264~3.025 Ma)是距今最近的气候持续温暖时期,然而黄土高原红黏土记录却显示了较弱的轨道周期,与气候模拟结果不一致.为了解决这一矛盾,本文利用一个新的季风降水代用指标,重建了晚上新世暖期东亚季风的降水变化.结果表明东亚季风降水变化在该时期以2万年周期为主,说明太阳辐射是重要的驱动力,加深了我们对东亚夏季风在暖期变化及规律的认识.此外,我们还发现季风降水的4万年周期与南半球冰量的变化呈同相位关系,说明CO_(2)/南极冰盖也可能是驱动中国北方降水的因素.

关 键 词：太阳辐射 南极冰盖 暖期 气候模拟 轨道周期 相位关系 地质历史时期 代用指标 

分 类 号：P426.6[天文地球—大气科学及气象学]