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马克思主义时代化的历史演生、现实动力与未来挑战 被引量:1
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作者 张伟 《广西社会科学》 CSSCI 北大核心 2011年第4期9-12,共4页
在推进马克思主义时代化进程中,需要弄清马克思主义时代化的历史演生过程、现实动力条件和未来迎接的挑战:与时俱进的"方法论"与社会主义"实践成果"呈现出马克思主义时代化的历史演生过程;"中国模式"与&q... 在推进马克思主义时代化进程中,需要弄清马克思主义时代化的历史演生过程、现实动力条件和未来迎接的挑战:与时俱进的"方法论"与社会主义"实践成果"呈现出马克思主义时代化的历史演生过程;"中国模式"与"后危机时代"指明了马克思主义时代化的现实动力;"误解"马克思主义与"和平演变"道出了马克思主义时代化的未来挑战。只有把握机遇应对挑战,才能推进马克思主义时代化发展。 展开更多
关键词 马克思主义时代化 历史演 现实动力 未来挑战
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教学中的运用——再演历史教学法
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作者 李梅 《兵团教育学院学报》 2019年第2期67-70,共4页
"再演历史"教学法是由哥伦比亚大学巴纳德学院历史教授马克·卡恩斯于1995年开创的,是一种让学生参与到根据经典作品精心设计的课堂角色扮演游戏中去的教学方法。该教学法由学生通过角色扮演来主动获取知识,是主动学习教... "再演历史"教学法是由哥伦比亚大学巴纳德学院历史教授马克·卡恩斯于1995年开创的,是一种让学生参与到根据经典作品精心设计的课堂角色扮演游戏中去的教学方法。该教学法由学生通过角色扮演来主动获取知识,是主动学习教学法中的一种,它很好地实现了美国通识教育的课程目标,对我国当前大学通识教育改革也具有重要的启示作用。文章从什么是"再演历史"教学法"、再演历史"教学法在课程中的具体运用及其所实现的通识教育目标等方面进行系统阐述,希望能够对这种新型教学法有一个更深刻地认识,同时希望我国高等教育能够合理借鉴这种教学法,提高教学效率,以便更好地促进我国大学通识教育的发展。 展开更多
关键词 历史教学法 通识教育 角色扮 游戏
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基于“历史复演法”的“苯的结构”教学设计
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作者 何柔颖 陈湛 《中学化学教学参考》 2023年第33期5-8,共4页
化学发展的历史能够作为重要的教学设计资源,将历史上化学家开展科学研究和解决科学问题的过程,设计为可供课堂教学应用的学生问题,需要经过历史事件考察、学生水平分析、问题转化等步骤。以“苯的结构”为例,探讨了基于“历史复演法”... 化学发展的历史能够作为重要的教学设计资源,将历史上化学家开展科学研究和解决科学问题的过程,设计为可供课堂教学应用的学生问题,需要经过历史事件考察、学生水平分析、问题转化等步骤。以“苯的结构”为例,探讨了基于“历史复演法”的化学教学设计框架与实施。 展开更多
关键词 化学史 教学设计 历史 苯的结构
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宝相花纹样研究 被引量:9
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作者 闫书龙 《商业文化》 2011年第9X期327-328,共2页
宝相花是我国传统装饰图案中最为常见一种花卉图案,早在战国时期就出现了它的雏形,它不是一成不变的装饰图形,在每个朝代都随着当时的文化、艺术审美做出相应的调整。本文通过大量的参考文献对对宝相花的历史演变、装饰特点进行解析。
关键词 宝相花 宝相纹样 历史演 稳定与动感
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Petrographic characteristics and paleoenvironmental history of Eocene lignites of Cambay basin, Western India 被引量:5
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作者 Prakash K. Singh Vijay K. Singh +1 位作者 M. P. Singh P. K. Rajak 《International Journal of Coal Science & Technology》 EI 2017年第3期214-233,共20页
Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is ... Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is used to reconstruct the paleodepositional history of these lignite sequences. The lignites of Cambay basin dominantly comprise huminite maceral group (71.6%-86.3%) followed by liptinite (10.1%-19.3%) and inertinite (3.6%-11.0%) maceral groups. The mineral matter varies from 9.0% to 20.0%. The petrography based facies model indicates that these lignites have high values of gelification index (GI) and low tissue preservation index revealing a continuous wet condition in the basin and a relatively slower rate of subsidence during the decay of organic matter. On several occasions, during the formation of seams in Tadkeshwar, Rajpardi and Vastan mines, the value of GI exceeded 10 which indicates a forest permanently flooded and the cause of pronounced degree of degradation. However, few sections in Tadkeshwar seam had relatively drier spells of environmental conditions due to fluctuation in the water table as revealed by moderately high content of inertinite macerals. This is specially indicated by the occurrence of funginite which normally thrives in the upper oxy- genated peatigenic layer and indicates prevalence of oxic conditions during plant deposition. Such conditions prevailed during a transgressive phase but there were intermittent fluvial activities also giving rise to supratidal flood plain as reflected in the form of associated carbonaceous shales in the basin. 展开更多
关键词 Cambay basin Western India Lignite MACERAL Paleodepositional environment
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Sedimentary Records of Mangrove Evolution During the Past one Hundred Years Based on Stable Carbon Isotope and Pollen Evidences in Maowei, SW China 被引量:4
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作者 XIA Peng MENG Xianwei +1 位作者 LI Zhen FENG Aiping 《Journal of Ocean University of China》 SCIE CAS 2016年第3期447-455,共9页
Mangroves accumulate sedimentary sequences, where cores can provide historical records of mangrove evolution with past climate change and human activity. The study traced the history of mangrove evolution during the p... Mangroves accumulate sedimentary sequences, where cores can provide historical records of mangrove evolution with past climate change and human activity. The study traced the history of mangrove evolution during the past one hundred years in a mangrove swamp of Maowei Sea, SW China. The sedimentation rates(0.38-0.95 cm yr^(-1)) were calculated on the basis of ln(^(210)Pb_(xs)/Al) and mass depth in the core sediments. Chemical tracers, such as δ^(13)C_(org) and C:N values, were utilized to trace the contribution of mangrove-derived organic matter using a ternary mixing model. Because of potential diagenetic alteration and / or overlap in the isotopic signatures of different components, simultaneous use of mangrove pollen diagrams can help to supplement some of these limitations. Combined with mangrove pollen, mangrove evolution was reconstructed and could be divided into three stages: flourishment(1886-1905 AD), slight degradation(1905-1949 AD) and rapid degradation period(1949-2007 AD), which was consistent with previous reports. The reclamation of mangrove swamps to shrimp ponds was the major reason for rapid degradation of mangrove ecosystems in recent years, rather than climate change in the region. 展开更多
关键词 mangrove evolution stable carbon isotope POLLEN climate change human activity
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The mitochondrial genomes of Macrocheraia grandis grandis and Myrmoplasta mira(Hemiptera:Heteroptera:Pentatomomorpha) and the unique mitogenome rearrangement in Pyrrhocoroidea 被引量:1
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作者 Yu MEN Fei YE +1 位作者 Yanhui WANG Qiang XIE 《Entomotaxonomia》 CSCD 2019年第2期96-113,共18页
Sequencing technology has developed rapidly in recent years. Complete or nearly complete mitochondrial genomes(mitogenomes) of 155 species from 47 families in Heteroptera have been sequenced. However, the amounts of m... Sequencing technology has developed rapidly in recent years. Complete or nearly complete mitochondrial genomes(mitogenomes) of 155 species from 47 families in Heteroptera have been sequenced. However, the amounts of mitogenomes between those families are unbalanced, which makes it difficult to correctly discern the patterns of mitogenome rearrangement in Heteroptera. Among 21 species from ten families, ten variations in mitogenome rearrangement had been previously reported, among which the translocation between tRNA-Thr and tRNA-Pro was considered as a synapomorphy of Pyrrhocoroidea based on two mitogenomes. As only one mitogenome in each of Largidae and Pyrrhocoridae had been sequenced to conclude the synapomorphy, more mitogenomes of Pyrrhocoroidea need to be explored. In this study, additional two mitogenomes of Pyrrhocoroidea(Macrocheraia grandis grandis(Gray, 1832) and Myrmoplasta mira Gerst-cker, 1892) were sequenced. Both of them also possess the same translocation between tRNA-Thr and tRNA-Pro, which reaffirms that this kind of rearrangement is a molecular synapomorphy of Pyrrhocoroidea. Moreover, we discovered a more complex rearrangement in Myrmoplasta mira, in which six nearly identical duplications of tRNA-Thr were found located downstream of tRNA-Pro. Considering the high biodiversity of Heteroptera, more mitogenomic studies are needed to improve our knowledge about mitogenome rearrangements and the potential synapomorphies. 展开更多
关键词 Pyrrhocoroidea MITOGENOME synapomorphy PHYLOGENOMICS evolutionary history
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Modelling and simulation of contact force in cold rotary forging 被引量:2
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作者 秦训鹏 《Journal of Central South University》 SCIE EI CAS 2014年第1期35-42,共8页
Cold rotary forging is an advanced and complex metal forming technology with continuous local plastic deformation.Investigating the contact force between the dies and the workpiece has a great significance to improve ... Cold rotary forging is an advanced and complex metal forming technology with continuous local plastic deformation.Investigating the contact force between the dies and the workpiece has a great significance to improve the life of the dies in cold rotary forging.The purpose of this work is to reveal the contact force responses in cold rotary forging through the modelling and simulation.For this purpose,a 3D elastic-plastic dynamic explicit FE model of cold rotary forging is developed using the FE code ABAQUS/Explicit.Through the modelling and simulation,the distribution and evolution of the contact force in cold rotary forging is investigated in detail.The experiment has been conducted and the validity of the 3D FE model of cold rotary forging has been verified.The results show that: 1) The contact force distribution is complex and exhibits an obvious non-uniform characteristic in the radial and circumferential directions; 2) The maximum contact force between the upper die and the workpiece is much larger than that between the lower die and the workpiece; 3) The contact force evolution history is periodic and every period experiences three different stages; 4) The total normal contact force is much larger than the total shear contact force at any given time. 展开更多
关键词 cold rotary forging metal forming SIMULATION contact force die life
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Paleoproductivity evolution in the West Philippine Sea during the last 700 ka 被引量:4
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作者 唐正 李铁刚 +2 位作者 常凤鸣 南青云 李青 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期435-444,共10页
In order to reconstruct the paleoproductivity evolution history of the West Philippine Sea during the last 700 ka, the vertical gradient of Δδ13C in dissolved inorganic carbon Δδ13C between those of foraminifera P... In order to reconstruct the paleoproductivity evolution history of the West Philippine Sea during the last 700 ka, the vertical gradient of Δδ13C in dissolved inorganic carbon Δδ13C between those of foraminifera Pulleniatina obliquiloculata and Cibicidoides wuellerstorfi) and planktonic foraminiferal assemblages were analysed in piston Core MD06-3047 retrieved from the Benham Rise (east of the Luzon Island). Paleoproductivity evolution in the West Philippine Sea during the last 700 ka is closely related to glacial-interglacial cycles and precession-controlled insolation. Controlling factors ofpaleoproductivity could have been both thermocline fluctuations related with ENSO-Iike processes and eolian input associated with East Asian winter monsoon, and the former could have been the primary factor. A higher productivity and a shallower thermocline coeval with the occurrence of low CO2 concentrations in the EPICA Dome C ice core might indicate that biological export production in the low-latitude could act as a significant sink in the global carbon cycle, and modify atmospheric CO2 concentrations. Spectral analysis further reveals that the paleoproductivity is mainly controlled by thermocline fluctuations subjected to ENSO processes responding to processional variability of insolation. High coherences in eccentricity, obliquity and precession periods fiuther revealing the close link between thermocline fluctuations, paleoproductivity and atmospheric CO2 levels. 展开更多
关键词 PALEOPRODUCTIVITY thermocline depth paleo-ENSO west Philippine Sea
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Water Conservancy and the Historical Evolvement of Lingnan Regional Culture
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作者 Fei Xiao 《Journal of Environmental Science and Engineering(A)》 2014年第3期131-140,共10页
The history of the formation and development of Chinese civilization is also a civilization history of water conservancy. Water not only gives birth to Chinese civilization but also gives birth to the unique regional ... The history of the formation and development of Chinese civilization is also a civilization history of water conservancy. Water not only gives birth to Chinese civilization but also gives birth to the unique regional culture in Lingnan. In the past thousands of year, from the ancient myths and legends of Lingnan water conservancy culture to the digging of efficacious Canal's integration of the nationalities in Lingnan, to the blending of water and culture of the Xijiang River and the North River of the Zhujiang water system and the formation of urban river culture, development of its generation, deduction and inheritance has the mutual penetration with the formation of water system and the variation of water conservancy which mutually influence the historical evolvement of Lingnan regional culture. 展开更多
关键词 Water conservancy Lingnan regional culture HISTORY evolvement.
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The transformation of China's economic and government functions
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作者 ZHOU Yu-feng 《Chinese Business Review》 2010年第2期56-60,共5页
The content of China's economic transformation is not single, and this article argues that it includes three parts. The first is the reform of economic system, the second is the change in the pattern of economic grow... The content of China's economic transformation is not single, and this article argues that it includes three parts. The first is the reform of economic system, the second is the change in the pattern of economic growth, and the third is the adjustment of economic structure. Government is the leading force of China's economic transformation, and repeated reform of government institutions has brought about some changes to government functions. But problems are obvious that lag changes of government functions have become an obstacle in China's economic transformation. This article describes the historical evolution and the reality of China's economic transformation, and analyzes the main reasons of lag changes in government functions, and reveals that the transformation of government functions is the key for successful transformation of China's economy. 展开更多
关键词 TRANSFORMATION China's economy government functions
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The Research on Historical Evolution and Inheritance Development of Ansai waist drum in China
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作者 Feng YANG 《International English Education Research》 2015年第1期1-3,共3页
This article from the perspective of sports science and sociology to explain the origin and development ofansai waist drum, analyzes the historical evolution of ansai waist drum, analysis of ansai waist drum in proble... This article from the perspective of sports science and sociology to explain the origin and development ofansai waist drum, analyzes the historical evolution of ansai waist drum, analysis of ansai waist drum in problems existing in the process of development, and according to the analysis and the reality put forward the countermeasures of development of ansai waist drum inheritance: transmission of ansai waist drum based on school, and innovation of art form, "waist drum troupe" building, the establishment of various rules and regulations and the drummer cultivation mechanism and strengthening network, books, magazines and other publicity and performances. 展开更多
关键词 Ansai waist drum Historical Evolution Inheritance Development
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Performance on the 2011 Certified Public Accountant (CPA) Examination for Large, Middle, and Small Historically Black Colleges and Universities (HBCUs)
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作者 Forrest Thompson 《Journal of Modern Accounting and Auditing》 2013年第12期1555-1563,共9页
There are over 100 historically black colleges and universities (HBCUs) in the United States. The majority of these HBCUs are located in the southeast section of the United States. HBCUs are a major supplier of cert... There are over 100 historically black colleges and universities (HBCUs) in the United States. The majority of these HBCUs are located in the southeast section of the United States. HBCUs are a major supplier of certified public accountants (CPAs) to the profession. Therefore, the performance of candidates from HBCUs should be of interest to various constituents including educators, employers, parents, students, and other stakeholders. The purpose of this paper is to provide statistical performance on the 2011 CPA examination for large, middle, and small HBCUs based upon the number of testing events taken. Taking a testing event is not the same as passing a testing event. This was the dichotomy between quantity and quality of HBCUs' performances. For large HBCUs, Morehouse University, North Carolina Agricultural and Technical State University (NC A&T), and Tennessee State University (TSU) were cited. For middle HBCUs, Albany State University, Norfolk State University (NSU), and North Carolina Central University (NCCU) were cited. For small HBCUs, Alcorn State University, Fisk University, and University of Maryland Eastern Shore (UMES) were cited. The dichotomy between quantity and quality is real. 展开更多
关键词 historically black colleges and universities (HBCUs) certified public accountant (CPA) exam testingevents pass rates
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Sites to Remember: Performing the Landscape in Cultural History
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作者 Janys Hayes 《Journal of Literature and Art Studies》 2016年第10期1221-1230,共10页
This paper aims to compare and contrast two site-specific performance productions, both designed to grapple with processes of cultural remembrance, whilst also operating as successful tourist attractions. The narrativ... This paper aims to compare and contrast two site-specific performance productions, both designed to grapple with processes of cultural remembrance, whilst also operating as successful tourist attractions. The narratives encompassed by both productions revolve around shared Australian histories, for audiences attracted by place and what it is able to represent. Re-enactments of past events call into the present a consideration of what still remains, with both shows enabling new subjective interpretations of earlier times. The defining difference between the two, however, rests in the context of each performance, in the one case as a commodification of heritage and in the other case as the desire to produce an artistic yet popular theatrical product. Ballarat's, Sovereign Hill's light and sound show, Blood on the Southern Cross celebrates and commemorates, in mega-spectacle style, the Eureka Stockade, one of Australia's key historical events. Using a mechanised display of the original goldmining site of the Eureka rebellion, the performance is operated by computers with video-projection, multi-phonic sound, and moving model forms, with audiences moved around the massive site on transporters. The Piccolo Tales, a contrasting performance most notably in terms of size, unfolds the history of Kings Cross, through its setting in the miniscule iconic Piccolo Bar, in one of the tiny side streets of Sydney's bustling and densest suburb. This paper encompasses an investigation of how the cultural inscriptions of the two specific sites interweave with the performance styles, materials, political and social positioning of the works. Previous performance studies examining site-specificity are utilised, including the author's analysis of particular festival performances as "place-making" (Hayes, 2012, 2013). Smith's (2009) model of "signposts" is used to consider acting within site-specific productions in a new light, whilst both performances are more completely analysed through Schneider's (2011) concept of incomplete pasts forming "cycles of memory". 展开更多
关键词 cultural history historical re-enactments memory PLACE-MAKING site-specific performance SovereignHill The Eureka Stockade
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Technological Evolution of Historic Structural Mortars
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作者 Vasiliki Pachta Maria Stefanidou Stavroula Konopisi Ioanna Papayianni 《Journal of Civil Engineering and Architecture》 2014年第7期846-854,共9页
Mortars are among the first building materials used in constructions, even from prehistoric times (8th millennium BC). Their study reveals a great source of information regarding the evolution of their technological... Mortars are among the first building materials used in constructions, even from prehistoric times (8th millennium BC). Their study reveals a great source of information regarding the evolution of their technological characteristics and application techniques, the availability and exploitation of raw materials, as well the wider socio-economic aspects of each era. The aim of this paper is to comparatively evaluate the analysis results from approximately 1,000 structural mortar samples taken from various monuments and historic buildings of Greece, dated from the Hellenistic period, until the beginning of the 20th century. The analysis focused in the determination of their physico-mechanical and chemical properties, such as porosity, apparent specific gravity, mechanical strength, aggregates type and granulometry and chemical composition. Through the results' evaluation, significant remarks can be made upon the evolution of the raw materials used (binding system, aggregates, additives), as well as regarding the final properties of historic structural mortars. It is concluded that hydrated lime was the main binding agent used for a long-lasting period of 2.5 millenniums, while mixed type binding systems based on lime and natural pozzolan were systematically used for producing durable mortars, resistant to humidity. In any case, it seems that ancient masons were fully aware of the significant role of mortars in constructions and were capable of exploiting the available raw materials and application techniques to the maximum. 展开更多
关键词 Structural mortars technological evolution physico-mechanical chemical properties.
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Evolution of Damage on Historical Heritage Buildings in Presence of Catastrophic Events and Aggressive Natural Phenomena
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作者 Elsa Garavaglia Chiara Molina 《Journal of Civil Engineering and Architecture》 2011年第7期585-595,共11页
The feasibility analysis of projects for the preservation of the historical heritage buildings is an important problem concerning the evaluation of "the total cost of intervention", which includes all the future dam... The feasibility analysis of projects for the preservation of the historical heritage buildings is an important problem concerning the evaluation of "the total cost of intervention", which includes all the future damage costs. The total cost of intervention represents a suitable measure of the expected deterioration risk and its evolution obviously depends on the damage process which buildings are subjected to. That damage phenomena affecting masonry buildings pleased into an aggressive environment are suitably modelled by renewal processes: this happens both in the case of catastrophic events, or in the case of the so-called "natural aging", in which damage comes off gradually in time. In the hypothesis ofa Markovian renewal process (Mrp) describing the damage process, the total cost of all the future damage is evaluated taking into account both the damage aspects: damages due to catastrophic aspects and damages due to aggressive environment, supposing different maintenance and/or rehabilitation scenarios. A semi-Markov process (s-Mp) is defined to model the damage rehabilitation history of buildings in presence of seismic events, natural ageing and rehabilitation strategies. The expected rewards connected to the process are defined; they represent a significant measure of the risk. 展开更多
关键词 Historical heritage buildings damaging phenomena rehabilitation strategies semi-Markov and renewal processes expected rewards.
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Information Entropy of Palaeocommunity in Geological History
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作者 曾勇 屈永华 +1 位作者 陈伟 吴财芳 《Journal of China University of Mining and Technology》 2003年第2期117-120,共4页
As an ecosystem in geological history, palaeocommunity has the essence of thermodynamics. This paper introduces the concept of entropy into the study of the evolution of palaeo-community, and proposes four parameters ... As an ecosystem in geological history, palaeocommunity has the essence of thermodynamics. This paper introduces the concept of entropy into the study of the evolution of palaeo-community, and proposes four parameters to represent the structure feature of palaeo-community. This theory is used to calculate the evolution mode of branchipod community of Maokou formation in Liziya area, Huaying Moumtain, Sichuan. 展开更多
关键词 palaeocommunity i succession informating i entropy
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Spatiotemporal distribution and historical evolution of polders in the Dongting Lake area, China 被引量:2
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作者 王卷乐 高孟绪 +1 位作者 郭海会 陈二洋 《Journal of Geographical Sciences》 SCIE CSCD 2016年第11期1561-1578,共18页
Dongting Lake is the largest lake in the middle reaches of the Yangtze River in China. For centuries, people inhabiting the Dongting Lake area have been reclaiming land and constructing dams for flood resistance, agri... Dongting Lake is the largest lake in the middle reaches of the Yangtze River in China. For centuries, people inhabiting the Dongting Lake area have been reclaiming land and constructing dams for flood resistance, agricultural production, and rural settlement, forming geographical entities known as polders. In this study, the regional spatial distributions of polders in the Dongting Lake area in 1949, 1998, and 2013 were obtained using historical maps and modern remotely sensed data, revealing changes since the establishment of the People's Republic of China. Nanxian County was then selected to demonstrate polder changes at the county level, because it has undergone the most dramatic changes in the area. Different polder change models for the Datonghu, Yule, and Renhe polders were analyzed for eight periods: 1644(the early Qing Dynasty), 1911(the late Qing Dynasty), 1930(the Republic of China), 1949(the People's Republic of China), 1963, 1970, 1998, and 2013. Three resulting polder evolution models are: 1) reclaiming polders from lakes, 2) integrating polders by stream merging, and 3) abandoning polders for flood release. The polder evolution models demonstrate the wisdom of local people in using land resources according to the specific regional conditions. Throughout their long-term historical evolution, the spatial distribution of polders in the Dongting Lake area tended to be homogeneous, and the degree of human disturbance tended to be stable. However, a shift occurred, from pure polder area growth or removal to more comprehensive management and protection of the regional environment. 展开更多
关键词 Dongting Lake polder spatiotemporal distribution landscape pattern evolution model
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Evolution of the 2015/16 El Nio and historical perspective since 1979 被引量:8
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作者 Yan XUE Arun KUMAR 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第9期1572-1588,共17页
The 2015/16 El Nio developed from weak warm conditions in late 2014 and NINO3.4 reached 3℃ in November 2015. We describe the characteristics of the evolution of the 2015/16 El Nio using various data sets including ... The 2015/16 El Nio developed from weak warm conditions in late 2014 and NINO3.4 reached 3℃ in November 2015. We describe the characteristics of the evolution of the 2015/16 El Nio using various data sets including SST, surface winds,outgoing longwave radiation and subsurface temperature from an ensemble operational ocean reanalyses, and place this event in the context of historical ENSO events since 1979. One salient feature about the 2015/16 El Nio was a large number of westerly wind bursts and downwelling oceanic Kelvin waves(DWKVs). Four DWKVs were observed in April-November 2015 that initiated and enhanced the eastern-central Pacific warming. Eastward zonal current anomalies associated with DWKVs advected the warm pool water eastward in spring/summer. An upwelling Kelvin wave(UWKV) emerged in early November 2015 leading to a rapid decline of the event. Another outstanding feature was that NINO4 reached a historical high(1.7℃), which was 1℃(0.8℃) higher than that of the 1982/83(1997/98) El Nio . Although NINO3 was comparable to that of the 1982/83 and 1997/98 El Nio , NINO1+2 was much weaker. Consistently, enhanced convection was displaced 20 degree westward, and the maximum D20 anomaly was about 1/3.1/2 of that in 1997 and 1982 near the west coast of South America. 展开更多
关键词 ENSO Sea surface temperature Westerly wind bursts Ocean Kelvin waves Thermocline variability Ocean reanalysis
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Clay mineral assemblages at IODP Site U1340 in the Bering Sea and their paleoclimatic significance 被引量:2
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作者 ZHANG Qiang CHEN MuHong +3 位作者 LIU JianGuo YU ZhaoJie ZHANG LanLan XIANG Rong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第5期707-717,共11页
Clay mineral assemblages and crystallinities in sediments from IODP Site 1340 in the Bering Sea were analyzed in order to trace sediment sources and reconstruct the paleoclimatic history of the Bering Sea since Plioce... Clay mineral assemblages and crystallinities in sediments from IODP Site 1340 in the Bering Sea were analyzed in order to trace sediment sources and reconstruct the paleoclimatic history of the Bering Sea since Pliocene (the last -4.3 Ma). The re- sults show that clay minerals at Site U1340 are dominated by illite, with a moderate amount of smectite and chlorite, and minor kaolinite. Sediment source studies suggest that the clay mineral assemblages and their sources in the studied core are controlled primarily by the climate conditions. During the warm periods, clay minerals originated mainly from the adjacent Aleutian Is- lands, and smectite/(illite+chlorite) ratios increased. During the cold periods, clay minerals from the Alaskan region distinctly increased, and smectite/(illite+chlorite) ratios declined. Based on smectite/(illite+chlorite) ratios and clay mineral crystallinities the evolutionary history of the paleoclimate was revealed in the Bering Sea. In general, the Bering Sea was characterized by warm and wet climate condition from 4.3 to 3.94 Ma, and then cold and dry condition associated with the enhanced volcanism from 3.94 to 3.6 Ma. Thereafter, the climate gradually became cold and wet, and then was dominated by a cold and dry condi- tion since 2.74 Ma, probably induced by the intensification of the Northern Hemisphere Glaciation. The interval from 1.95 to 1.07 Ma was a transitional period of the climate gradually becoming cold and wet. After the middle Pleistocene transition (1.07 to 0.8 Ma), the Bering Sea was governed mainly by cold and wet climate with several intervals of warm climate at -0.42 Ma (MIS 11), -0.33 Ma (MIS 9) and ~0.12 Ma (MIS 5), respectively. During the last 9.21 ka (the Holocene), the Bering Sea was characterized primarily by relatively warm and wet climatic conditions. 展开更多
关键词 the Bering Sea Site U1340 clay mineral CRYSTALLINITY PALEOCLIMATE
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