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Science China Earth Sciences 2010年第5期53卷 633-641页

作者： edwards r. lawrence Department of Geology and Geophysics University of Minnesota

Based on 33 U/Th dates and 1020 oxygen isotopic data from stalagmite Y1 from Yamen Cave, Guizhou Province, China, a record of the Asian Summer Monsoon (ASM) was established. The record covers the last deglaciation and the early Holocene (from 16.2 to 7.3 ka BP) with an average oxygen isotope resolution of 9 years. The main millennial-scale deglacial events first identified in Greenland (Greenland Interstadial Events: GIS 1e through GIS 1a) and later in China are clearly present in the Y1 record. By analogy to earlier work, we refer to these as Chinese Interstadials (CIS): CIS A.1e to CIS A.1a. The onset of these events in Y1 δ18O records are nominally dated at: 14750±50, 14100±60, 13870±80, 13370±80, and 12990±80 a BP. The end of CIS A.1a or the beginning of the Younger Dryas (YD) event is nominally at 12850±50 a BP and the end of the YD dates to 11500±40 a BP. The δ18O values shift by close to 3‰ during the transition into the Bφlling-Allerφd (BA, the onset of CIS A.1e) and at the end of the YD. Comparisons of Y1 to previously published early Holocene records show no significant phase differences. Thus, the East Asia Monsoon and the Indian Monsoon do not appear to have been out of phase during this interval. The Y1 record confirms earlier work that suggested that solar insolation and North Atlantic climate both affect the Asian Monsoon.

关键词： stalagmite Asian Monsoon the last deglaciation Holocene U-series dating Yamen Cave

Comment on "On linking climate to Chinese dynastic change:Spatial and temporal variations of monsoonal rain"

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Chinese Science Bulletin 2010年第32期55卷 3734-3737页

作者： CHENG Hai edwards r lawrence HAUG Gerald H Institute of Global Environmental Change Xi'an Jiaotong University Xi'an 710049 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA Geological Institute Department of Earth Sciences ETH Ziirich CH-8092 Ziirich Switzerland

An article by Zhang et al. questions the interpretation of our oxygen isotope record from Wanxiang Cave and the sediment titanium record from Lake Huguang Maar,and the possible linkage between climate change and Chinese culture. In response,we explain that their approach lacks logical rigor and their major argument is broadly consistent with,rather than contradictory to our original conclusions. We also note that climate-culture relationships similar to those that we observe in China have been observed for other cultures around the world.

关键词：气候变化时空变化中国雨水季风挂钩氧同位素记录中华文化

Long-term trend and abrupt events of the Holocene Asian monsoon inferred from a stalagmiteδ^(18)O record from Shennongjia in Central China

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Chinese Science Bulletin 2006年第2期51卷 221-228页

作者： SHAO Xiaohua WANG Yongjin CHENG Hai KONG Xinggong WU Jiangying edwards r. lawrence College of Geography Science Nanjing Normal University Nanjing 210097 China Department of Geology and Geophysics Minnesota University MN 55455 USA

A high-resolution oxygen-isotope record from a thorium-uranium-dated stalagmite from Shanbao Cave at Shennongjia reflects variations in the amount of monsoon precipitation for the period from 11.5 to 2.1 ka (1 ka = 1000 cal aBP). Between 11.5 and 9.3 ka, a sharp decrease in δ18O indicates a rapid increase in monsoon precipitation. An interval of generally high monsoon precipitation is observed between 9.3 and 4.4 ka. An arid period has prevailed between 4.4 and 2.1 ka. The long-term trend of Shanbao record appears to follow summer insolation at 33°N latitude. An abrupt decrease in monsoon precipitation around 4.3 ka is synchronous with the collapse of Neolithic culture in central China. This abrupt change could have resulted from the amplifi- cation of the gradually decreased summer insolation by the positive vegetation-atmosphere-aerosol feed- back. The weakened Asian monsoon events were in concert with decreased Greenland temperature dur- ing the early Holocene, centered at 8.2, 8.6, 9.3, 10.2 and 11.0 ka. This correlation suggests that changes in low-latitude monsoon are connected with climate change in high-latitude polar region.

关键词：全新世亚洲季风长期趋势突发事件古气候氧同位素中国神龙架石笋

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赣北石笋记录的新仙女木事件

第四纪研究 2019年第4期39卷 994-1005页

作者：张海伟程海蔡演军 Kathayat Gayatri 宁有丰 edwards r lawrence 孟秉霖西安交通大学全球变化研究院陕西西安710054 Department of Earth Sciences University of Minnesota Minneapolis MN 55455 USA 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陕西西安710061

新仙女木事件(Younger Dryas,简称YD)是末次冰消期升温过程中发生的一次北半球急剧降温事件,目前全球范围多个地区的地质记录中均有发现该事件的印记.然而,受限于定年误差或采样分辨率等因素,关于YD事件的精确起止时间、精细内部结构和... 详细信息

新仙女木事件(Younger Dryas,简称YD)是末次冰消期升温过程中发生的一次北半球急剧降温事件,目前全球范围多个地区的地质记录中均有发现该事件的印记.然而,受限于定年误差或采样分辨率等因素,关于YD事件的精确起止时间、精细内部结构和触发机制仍存在争议.本研究利用江西北部神农宫溶洞内一支文石石笋SN29(总长度426 mm,其中距离顶部220~388 mm用于本研究),通过高精度 230Th定年和氧、碳稳定同位素测试分析,建立了13614~10811 a B. P.期间平均分辨率12年的石笋氧同位素(δ18O)变化序列.该记录最为显著的特征是δ18O值在12851~11575 a B. P.时段偏正1. 7‰,指示了一次显著的弱季风突变事件,响应于北大西洋YD事件. SN29为高铀含量文石石笋且生长速率较快,精确界定了响应于YD事件的东亚弱季风事件的起止时间和精细内部结构.结果表明: YD期间, SN29记录的东亚弱夏季风事件的开始时间为 12851±16 a B. P.,经历了约249年;结束过程开始于11575±19 a B. P.,经历了约146年;整个YD弱季风事件共持续了 1276±35年.东亚季风区各石笋δ18O记录的YD弱季风事件在误差范围内基本一致,且与格陵兰冰芯δ18O记录和低纬度其他记录的发生时间一致,支持YD时期东亚夏季风减弱事件可能是对大量淡水进入北大西洋导致径向翻转流减弱、北半球变冷、ITCZ南移的快速响应的假说.

关键词：新仙女木事件(Younger Dryas) 石笋氧同位素东亚季风神农宫

葫芦洞石笋记录的19．9-17．1ka BP东亚夏季风增强事件

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中国科学（D辑） 2009年第1期39卷 61-69页

作者：吴江滢汪永进程海 edwards r. lawrence 南京师范大学地理科学学院南京210046 Department of Geology and Geophysics University of MinnesotaMinneapolisMinnesota 55455USA

南京葫芦洞石笋（No．H82）高分辨率δ^18 O序列已表明16．5～10．3ka BP时段东亚季风与极地气候在千年尺度事件上存在耦合关系．现根据7个高精度^230Th年龄和573个δ^18 O数据，将这一石笋的高分辨率δ^18 O时间序列延伸至22．1ka BP... 详细信息

南京葫芦洞石笋（No．H82）高分辨率δ^18 O序列已表明16．5～10．3ka BP时段东亚季风与极地气候在千年尺度事件上存在耦合关系．现根据7个高精度^230Th年龄和573个δ^18 O数据，将这一石笋的高分辨率δ^18 O时间序列延伸至22．1ka BP，从而提供了末次盛冰期10a分辨率的连续东亚季风气候记录．石笋δ^18 O记录表明H1事件内部的次级季风减弱事件与格陵兰寒冷事件在世纪尺度上具有同步性．该记录显示在19．9～17．1ka BP存在显著的东亚夏季风增强事件，其平均夏季风强度相当于BФlling暖期的1／2，夏季风最强时甚至接近于BФlling暖期．这一季风增强事件在北半球海洋和陆地记录中均有不同程度的体现，可能是热带太平洋Super-ENSO响应于岁差周期太阳辐射的结果．

关键词：南京葫芦洞石笋东亚夏季风增强事件

Demonstration of Covalent Sidewall Functionalization of Single Wall Carbon Nanotubes by NMr Spectroscopy:Side Chain Length Dependence on the Observation of the Sidewall sp^(3)Carbons

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Nano research 2008年第1期1卷 72-88页

作者： Liling Zeng lawrence B.Alemany Christopher L.edwards Andrew r.Barron richard E.Smalley Institute for Nanoscale Science and Technology and Department of Chemistry Rice UniversityHoustonTX 77005USA

Carboxylic acid-functionalized single walled carbon nanotubes(SWNTs)prepared via the reaction of an amino acid,NH2(CH2)nCO2H where n=1(glycine,GLY),5(6-aminohexanoic acid,AHA),10(11-aminoundecanoic acid,AUDA),with fl uorinated single walled carbon nanotubes(F-SWNTs)have been characterized by MAS 13C NMr *** ease of observing the aliphatic CH2 groups and the resolution of the signal are dependent on the length of the amino acid’s aliphatic *** have proposed that where substituent chains are short(making NMr data collection difficult)chemical modification to extend the chain length should alleviate analysis *** this regard,we have investigated the esterifi cation of the carboxylic acid *** amino acid-functionalized SWNTs were esterified with an appropriate alcohol to ensure parity of the overall substituent length,i.e.,GLY-SWNT(C1)+1-dodecanol(C_(12))=DOD-GLY-SWNT(1),AHA-SWNT(C_(5))+1-octanol(C_(8))=OCT-AHA-SWNT(2),and AUDA-SWNT(C_(10))+1-propanol(C_(3))=PrO-AUDA-SWNT(3).The 13C NMr shift for the sp3 nitrogen-substituted carbon atoms of the SWNT sidewall is observed atδ≈75 *** the length of SWNT sidewall functional groups enhances the ability to observe the sidewall sp^(3)*** methylene carbon signal intensity is less attenuated in the dipolar dephasing spectrum of the ester-functionalized SWNTs than their associated amino acid derivatives,suggesting more motional freedom of the side chain in the solid *** confi rmation of the dipolar dephasing spectral effects was assisted by the characterization of the ester of AUDA-SWNT with 1,3-propanediol:PPD-AUDA-SWNT(4).

关键词： Single walled carbon nanotube(SWNT) nuclear magnetic resonance(NMr) esterification amino acid functionalization

Great flood in the middle-lower Yellow river reaches at 4000 a BP inferred from accurately-dated stalagmite records

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Science Bulletin 2018年第4期63卷 206-208页

作者： Liangcheng Tan Chuan-Chou Shen Yanjun Cai Hai Cheng r.lawrence edwards State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Open Studio for Oceanic-Continental Climate and Environment Changes Qingdao National Laboratory for Marine Science and Technology Institute of Global Environmental Change Xi’an Jiaotong University High-Precision Mass Spectrometry and Environment Change Laboratory (HISPEC) Department of Geosciences Taiwan University Department of Earth Sciences University of Minnesota

recently,Wu et al.[1]suggested an earthquake-induced landslide dam outburst flood on the eastern Tibetan Plateau at 1920BCE(3870 a BP,BP denotes year before 1950 CE)caused the Great Flood in the middle-lower Yellow river reaches,and resulted in the founding of Xia Dynasty at 3850 a *** age is$150–300younger than the previously estimated age of the Xia Dynasty[2].While the geological evidence of the outburst flood。

关键词：石笋记录活动范围大洪水 BP 黄河黄土高原 BCE 幻灯片

An annually laminated stalagmite from the eastern Qinghai-Tibetan Plateau provides evidence of climate instability during the early MIS5e in the Asian summer monsoon

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Science China Earth Sciences 2023年第5期66卷 1147-1164页

作者： Tao GAO Pingzhong ZHANG Hai CHENG Leilei ZHANG Xinhu LI Hongyu SHI Wei JIA Youfeng NING Hanying LI r.lawrence edwards Key Laboratory of Mineral resources in Western China(Gansu Province)and School of Earth Sciences Lanzhou UniversityLanzhou730000China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an710054China Department of Earth Sciences University of MinnesotaMinneapolis55455USA

The Marine Isotope Stage(MIS5e)is characterized by a warmer climate than that of the pre-industrial period,and serves as an analog for the Current Warm Period(CWP).However,uncertainties persist regarding its climatic ***,we retrieved a stalagmite(WXB075)from Wanxiang Cave in the eastern Qinghai-Tibetan Plateau,and employed abs-olute^(230)Th dating and relative annual layer data to establish a high-precision chronological framework for reconstructing the history of the Asian summer monsoon(ASM)and environmental evolution during early MIS5e with multiple *** findings indicate that the annually laminated stalagmite was formed during Cooling Event 27(C27).The deposition of WXB075 experienced a hiatus(~125.58 ka BP)due to a significant cooling event in the North Atlantic,which may be linked to the unstable climate in the Northern ***,the impact of meltwater discharge in high northern latitudes results in a two-phase evolution of the ASM,i.e.,an initial weaker stage followed by a gradual increase(with exception of deposition hiatus).The climatic instability of ASM is generally characterized by a quasi-60 year cycle that affects vegetation conditions,biological productivity,and karst hydroclimate ***,the increase in meltwater and decrease in temperature in the Northern Hemisphere have led to a weakened ASM and subsequent reduction in ***,vegetation degradation above the cave has occurred along with a slowdown of karst *** vegetation conditions,organic matter content,and wet/drought of the karst hydroclimate were affected by both the large-scale monsoon circulation and local environment during extreme weakening(strengthening)of the monsoon when high-frequency climatic events of ASM occurred.A comparison ofδ^(18)O records between early MIS5e and the past 2000 years reveals that the climate during early MIS5e differed significantly from that of CWP,Medieval Warm Period(MWP),and Dark Age Co

关键词： Eastern Qinghai-Tibetan Plateau Climate instability Wanxiang Cave stalagmite Asian summer monsoon Environmental response Deposition hiatus

Summer Monsoon rainfall Variability in Central China over the Past 4700 Years and Its Possible Link to Solar Activity

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Journal of Meteorological research 2021年第4期35卷 594-606页

作者： Jingwei ZHANG Kan ZHAO Xinggong KONG Yongjin WANG Xianfang WANG Shushuang LIU Zhenjun WANG Hai CHENG r.lawrence edwards School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China School of Geography Science Nanjing Normal UniversityNanjing 210023China Key Laboratory ofPoyang LakeWetland and Watershed research of Ministry of Education Jiangxi Normal UniversityNanchang 330022China Lanling NO.4 Middle School Linyi 277700China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China Department of Geology and Geophysics University of MinnesotaMinneapolis MN55455USA

Based on 467 pairs ofδ^(18)O andδ^(13)C records and 8230 Th dates from a stalagmite(BF4)from Xiniu Cave,central China,we present a reconstruction of 9-yr resolution monsoon rainfall record for the past 4700 ***δ^(18)O record shows good coherence with East Asian summer monsoon(EASM)rainfall proxies from adjacent regions during the overlapping intervals,suggesting thatδ^(18)O signal in BF4 can be interpreted as a monsoon rainfall ***δ^(13) C variations are related to changes in local processes at the cave site,and regional rainfall and temperature *** on theδ18 O record,a series of dry periods can be identified at 4500-4200,3500-3200,2800-2500,1900-1600,1400-1200,700-500,and 400-200 yr BP,while a series of wet periods can be identified at 4200-3600,2400-2200,3200-2800,1100-900,600-400,and 200-100 yr *** spectrum analysis on ourδ^(18) O record reveals significant cycles at 470 and 80 yr,coinciding with the typical solar periodic *** result suggests that changes in solar activity play a dominant role in driving centennial-decadal monsoon rainfall variation in central *** to minor changes in solar irradiance(less than 1.5 W m^(-2))over the past 4700 years,our record was further compared to the El Nino-Southern Oscillation(ENSO)and Pacific Decadal Oscillation(PDO)proxies,confirming that solar forcing on monsoon rainfall changes might be amplified by the ENSO and PDO *** 600 to 150 yr BP(the Little Ice Age,LIA),a positive shift of 2‰can be revealed in both theδ^(18)O andδ^(13)C records,indicating a cold/dry climatic *** comparing ourδ^(18)O andδ^(13)C records with historical documents,we suggest that the climatic deteriorations between 450 and 250 yr BP may have caused serious social unrest at the end of the Ming Dynasty.

关键词： stalagmite record Xiniu Cave solar activity El Nino-Southern Oscillation(ENSO) Pacific Decadal Oscillation(PDO) amplify mechanism Little Ice Age(LIA)

Preliminary Studies of Speleothem in Central Asia

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 2279-2280页

作者： TAN Liangcheng SONG Yougui CAI Yanjun AN Zhisheng rustam OrOZBAEV Yunus MAMADJANOV lawrence r.edwards CHENG Hai LI Dong LI Yue State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of Sciences Institute of Global Environmental Change Xi’an Jiaotong University research Center for Ecology and Environment of Central Asia (Bishkek) Chinese Academy of Sciences Institute of Geology National Academy of Sciences of Kyrgyz Republic Institute of Geology Earthquake Engineering and SeismologyAcademy of Sciences of the Republic of Tajikistan Department of Earth Sciences University of Minnesota

The Westerlies is important in linking the Northem high latitude, North Atlantic and East Asian monsoon. The location and intensity of the Westerly jet can not only control the climate of central Asia （including northwest arid China）, but also significantly influence the climate of the East Asian monsoon region. However, it remains unclear of the variability of the Westerlies in Asia on multiple timeseales and their global linkage.

关键词： Preliminary Studies of Speleothem in Central Asia