人为气溶胶排放导致最近80年东亚夏季风在过去四个世纪以来空前减弱  

Anthropogenic aerosols cause recent pronounced weakening of Asian Summer Monsoon relative to last four centuries

作　　者：刘禹[1,2,3,4] 蔡文炬 孙长峰 宋慧明 Kim MCobb[7] 李建平 Steven WLeavitt 吴立新 蔡秋芳[1,3] 刘若时 Benjamin Ng Paolo Cherubini[10] Ulf Büntgen 宋怡 王国建 雷莺 晏利斌 李强[1,3] 马永永 方丛羲[1] 孙军艳[1] 李旭祥[9] Deliang Chen Hans WLinderholm LIU Yu;CAI Wenju;SUN Changfeng;SONG Huiming;Kim M.Cobb;LI Jianping;Steven W.Leavitt;WU Lixin;CAI Qiufang;LIU Ruoshi;Benjamin Ng;Paolo Cherubini;Ulf Büntgen;SONG Yi;WANG Guojian;LEI Ying;YAN Libin;LI Qiang;MA Yongyong;FANG Congxi;SUN Junyan;LI Xuxiang;Deliang Chen;Hans W.Linderholm(State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710061,China;CAS Center for Excellence in Quaternary Science and Global Change,Xi’an 710061,China;Laboratory for Ocean Dynamics and Climate,Pilot Qingdao National Laboratory for Marine Science and Technology,Qingdao 266237,China;Interdisciplinary Research Center of Earth Science Frontier and Joint Center for Global Change Studies,Beijing Normal University,Beijing 100875,China;Physical Oceanography Laboratory/CIMST,Ocean University of China and Qingdao National Laboratory for Marine Science and Technology,Qingdao 266237,China;CSIRO Marine and Atmospheric Research,Aspendale,VIC 3195,Australia;School of Earth and Atmospheric Sciences,Georgia Institute of Technology,Atlanta,GA 30332,USA;The Laboratory of Tree-Ring Research,The University of Arizona,Tucson,AZ 85721,USA;School of Human Settlements and Civil Engineering,Xi'an Jiaotong University,Xi’an 710049,China;Swiss Federal Institute for Forest,Snow and Landscape Research,CH-8903 Birmensdorf,Switzerland;Department of Geography,University of Cambridge,Cambridge CB23EN,UK;Global Change Research Centre and Masaryk University,60177 Brno,Czech Republic;Shaanxi Meteorological Observatory,Xi’an 710014,China;Climate Group,Department of Earth Sciences,University of Gothenburg,Box 100,SE-40530 Gothenburg,Sweden)

机构地区：[1]中国科学院地球环境研究所黄土与第四纪地质国家重点实验室,西安710061 [2]中国科学院第四纪科学与全球变化卓越创新中心,西安710061 [3]青岛海洋科学与技术试点国家实验室-海洋动力过程与气候功能实验室,青岛266237 [4]北京师范大学地球科学前沿交叉研究中心和全球变化研究联合中心,北京100875 [5]中国海洋大学物理海洋教育部重点实验室和青岛海洋科学与技术国家实验室,青岛266237 [6]CSIRO Marine and Atmospheric Research,Aspendale,VIC 3195,Australia [7]School of Earth and Atmospheric Sciences,Georgia Institute of Technology,Atlanta,GA 30332,USA [8]The Laboratory of Tree-Ring Research,The University of Arizona,Tucson,AZ 85721,USA [9]西安交通大学人居环境与建筑工程学院,西安710049 [10]Swiss Federal Institute for Forest,Snow and Landscape Research,CH-8903 Birmensdorf,Switzerland [11]Department of Geography,University of Cambridge,Cambridge CB23EN,UK [12]Global Change Research Centre and Masaryk University,60177 Brno,Czech Republic [13]陕西省气象局,西安710014 [14]Climate Group,Department of Earth Sciences,University of Gothenburg,Box 100,SE-40530 Gothenburg,Sweden

出　　处：《地球环境学报》2019年第6期527-542,共16页Journal of Earth Environment

基　　金：国家自然科学基金项目(41630531);大气重污染成因与治理攻关项目(DQGG0104);中科院项目(QYZDJSSW-DQC021,XDPB05,GJHZ1777);黄土与第四纪地质国家重点实验室项目(SKLLQGZD1701)。

摘　　要：亚洲夏季风(Asian Summer Monsoon,ASM)对亚洲数十亿人口的生存、亚洲生态系统和生物多样性的分布、以及农业生产(粮食安全)和工业活动影响严重。因此了解ASM过去时空变化及其动力学过程对陆地生态系统、水资源、森林和景观研究至关重要。近几十年,器测记录显示以降水量为代表的ASM强度一直在减弱,但这一减弱趋势的起始时间和动力学过程尚不清楚。为此,第一次集成了ASM西部-中部边缘带10个对降水敏感的树木年轮宽度年表,重建了公元1566年以来反映ASM强度变化的降水序列。重建结果不仅捕捉到了ASM过去4个世纪以来强弱变化历史,也反映出历史上蝗灾与弱季风的关联。特别是发现了最近80年具有过去448年中前所未有的、最为强烈的、显著且持续时间最长的ASM强度减弱趋势。这一减弱趋势与在温室效应影响下ASM本该增强的预期大相庭径。耦合气候模型实验表明,北半球人为硫酸盐气溶胶排放的逐渐增加,对ASM减弱起了决定性作用。Background,aim,and scope The Asian Summer Monsoon(ASM)affects ecosystems,biodiversity,and food security of billions of people.In recent decades,ASM strength(as represented by precipitation)has been decreasing,but instrumental measurements span only a short period of time.The initiation and the dynamics of the recent trend are unclear.As a result,the properties of the recent ASM decreasing trend,including whether it is a part of a longer-term trend must be understood.Several forcing factors may affect the strength of the ASM,including solar variability,volcanic eruptions,and anthropogenic aerosols.So how aerosols and the ASM interact will also be examined given that concentration of aerosols in northwest China has been increasing over the past several decades.Materials and methods Here for the first time,we use an ensemble of 10 tree ring-width chronologies from the west-central margin of ASM,to reconstruct detail of monsoonal precipitation variability from July of previous year to June of current year(PJJ)back to 1566 CE.The 10 tree ring-width chronologies are selected on the basis that they are sensitive only to rainfall,providing not only a higher-resolution but also an appropriate and direct proxy of the ASM over reconstruction from previous studies.Results The reconstructed PJJ time series is a proxy for the ASM,measuring the ASM strength over its marginal zone.The reconstruction captures weak/strong ASM events,and it is found that historical severe droughts and locust plague disasters both appear during weak ASM events.Notably,we found an unprecedented 80-year trend of decreasing ASM strength within the context of the 448-year reconstruction,which is contrary to what is expected from greenhouse warming.Comparison of two sets of historical model experiments(10 runs each)with and without increasing anthropogenic aerosols shows that this unprecedented decreasing trend is likely due to increasing anthropogenic aerosols,highlighting that the ASM-weakening effect of increasing anthropogenic sulfate aerosols could

关 键 词：东亚夏季风 树木年轮 降水重建 人为气溶胶 ASM减弱趋势 

分 类 号：P467[天文地球—大气科学及气象学] P425.42[环境科学与工程—环境工程] X513