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Anthropogenic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s 被引量:1
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作者 Qin SU Buwen DONG +1 位作者 Fangxing TIAN Nicholas P.KLINGAMAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期233-246,共14页
The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characteriz... The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the present day(PD,1994–2011) is double that in the early period(EP, 1964–81);the duration of HDEs increases by 60%. Climate experiments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthropogenic forcing to HDE decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on HDE changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of HDEs to GHG and AA changes are also revealed. 展开更多
关键词 concurrent hot and dry events decadal variation greenhouse gases aerosol emissions
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The Role of Underlying Boundary Forcing in Shaping the Recent Decadal Change of Persistent Anomalous Activity over the Ural Mountains 被引量:1
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作者 Ting LEI Shuanglin LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1496-1510,1661-1667,共22页
Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variatio... Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variations are related to a large-scale circulation shift over the Eurasian Continent. The effects of underlying sea ice and sea surface temperature(SST) anomalies on the Ural PAE and the related atmospheric circulation were explored by Atmospheric Model Intercomparison Project(AMIP) experiments from the Coupled Model Intercomparison Project Phase 6 and by sensitivity experiments using the Atmospheric General Circulation Model(AGCM). The AMIP experiment results suggest that the underlying sea ice and SST anomalies play important roles. The individual contributions of sea ice loss in the Barents-Kara Seas and the SST anomalies linked to the phase transition of the Pacific Decadal Oscillation(PDO) and Atlantic Multidecadal Oscillation(AMO) are further investigated by AGCM sensitivity experiments isolating the respective forcings.The sea ice decline in Barents-Kara Seas triggers an atmospheric wave train over the Eurasian mid-to-high latitudes with positive anomalies over the Urals, favoring the occurrence of Ural PAEs. The shift in the PDO to its negative phase triggers a wave train propagating downstream from the North Pacific. One positive anomaly lobe of the wave train is located over the Ural Mountains and increases the PAE there. The negative-to-positive transition of the AMO phase since the late-1990s causes positive 500-h Pa height anomalies south of the Ural Mountains, which promote a southward shift of Ural PAE. 展开更多
关键词 Ural persistent anomaly Pacific decadal oscillation Atlantic multidecadal oscillation sea ice loss in Barents-Kara Seas
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Decadal Changes in Dry and Wet Heatwaves in Eastern China:Spatial Patterns and Risk Assessment
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作者 Yue ZHANG Wen ZHOU Ruhua ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期2011-2026,共16页
Under global warming,understanding the long-term variation in different types of heatwaves is vital for China’s preparedness against escalating heat stress.This study investigates dry and wet heatwave shifts in easte... Under global warming,understanding the long-term variation in different types of heatwaves is vital for China’s preparedness against escalating heat stress.This study investigates dry and wet heatwave shifts in eastern China over recent decades.Spatial trend analysis displays pronounced warming in inland midlatitudes and the Yangtze River Valley,with increased humidity in coastal regions.EOF results indicate intensifying dry heatwaves in northern China,while the Yangtze River Valley sees more frequent dry heatwaves.On the other hand,Indochina and regions north of 25°N also experience intensified wet heatwaves,corresponding to regional humidity increases.Composite analysis is conducted based on different situations:strong,frequent dry or wet heatwaves.Strong dry heatwaves are influenced by anticyclonic circulations over northern China,accompanied by warming SST anomalies around the coastal midlatitudes of the western North Pacific(WNP).Frequent dry heatwaves are related to strong subsidence along with a strengthened subtropical high over the WNP.Strong and frequent wet heatwaves show an intensified Okhotsk high at higher latitudes in the lower troposphere,and a negative circumglobal teleconnection wave train pattern in the upper troposphere.Decaying El Niño SST patterns are observed in two kinds of wet heatwave and frequent dry heatwave years.Risk analysis indicates that El Niño events heighten the likelihood of these heatwaves in regions most at risk.As global warming continues,adapting and implementing mitigation strategies toward extreme heatwaves becomes crucial,especially for the aforementioned regions under significant heat stress. 展开更多
关键词 decadal changes dry heatwave wet heatwave eastern China
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Decadal prediction skill for Eurasian surface air temperature in CMIP6 models
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作者 Yanyan Huang Ni Huang Qianfei Zhao 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期9-13,共5页
评估CMIP6年代际预测试验对季节平均SAT的预测技巧的结果表明:模式不能有效预测冬季和秋季SAT的年代际变率.IPSL-CM6A-LR和多模式集合平均对于春季SAT展现了预测技巧,其中对于变率的预测技巧好于振幅的结果.基于蒙古和我国华北地区的显... 评估CMIP6年代际预测试验对季节平均SAT的预测技巧的结果表明:模式不能有效预测冬季和秋季SAT的年代际变率.IPSL-CM6A-LR和多模式集合平均对于春季SAT展现了预测技巧,其中对于变率的预测技巧好于振幅的结果.基于蒙古和我国华北地区的显著预测技巧,模式对于夏季SAT表现出最佳的预测水平.与外部强迫相比,模式对于SAT的预测技巧可能来自初始化.模式中的一个明显系统性误差值得注意,即模式中冬季SAT的变率可以持续到其他季节,而在观测中其他季节的SAT变化与冬季SAT相对独立. 展开更多
关键词 欧亚 地表温度 年代际预测 CMIP6 DCPP
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Progress and future prospects of decadal prediction and data assimilation:A review
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作者 Wen Zhou Jinxiao Li +5 位作者 Zixiang Yan Zili Shen Bo Wu Bin Wang Ronghua Zhang Zhijin Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期53-62,共10页
年代际预测,也称为“近期气候预测”,旨在预测未来1-10年内的气候变化,是气候预测和气候变化研究领域的一个新关注点.它位于季节至年际预测和长期气候变化预测之间,结合了初值问题和外部强迫问题的两个方面.年代际预测的核心技术在于用... 年代际预测,也称为“近期气候预测”,旨在预测未来1-10年内的气候变化,是气候预测和气候变化研究领域的一个新关注点.它位于季节至年际预测和长期气候变化预测之间,结合了初值问题和外部强迫问题的两个方面.年代际预测的核心技术在于用于模式初始化的同化方法的准确性和效率,其目标是为模式提供准确的初始条件,其中包含观测到的气候系统内部变率,年代际预测的初始化通常涉及在耦合框架内同化海洋观测,其中观测到的信号通过耦合过程传递到其他分量,如大气和海冰.然而,最近的研究越来越关注在海洋-大气耦合模式中探索耦合数据同化(CDA),有人认为CDA有潜力显著提高年代际预测技巧.本文综合评述了该领域的三个方面的研究现状:初始化方法,年代际气候预测的可预测性和预测技巧,以及年代际预测的未来发展和挑战. 展开更多
关键词 年代际预测 四维数据同化 海气相互作用
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Influence of Continental Atmospheric Forcing on the Decadal Variability of the West African Monsoon
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作者 Adjoua Moïse Landry Famien Sandrine Djakouré +3 位作者 Bi Tra Jean Claude Youan Serge Janicot Abé Delfin Ochou Arona Diedhiou 《Atmospheric and Climate Sciences》 2024年第1期1-28,共28页
The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability... The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability involves the role of atmospheric dynamics, linked in particular to the Saharan Heat Low (SHL). This article addresses this question by comparing the sets of preindustrial control and historical simulation data from climate models carried out in the framework of the CMIP5 project and observations data over the 20<sup>th</sup> century. Through multivariate statistical analyses, it was established that decadal modes of ocean variability and decadal variability of Saharan atmospheric dynamics significantly influence decadal variability of monsoon precipitation. These results also suggest the existence of external anthropogenic forcing, which is superimposed on the decadal natural variability inducing an intensification of the signal in the historical simulations compared to preindustrial control simulations. We have also shown that decadal rainfall variability in the Sahel, once the influence of oceanic modes has been eliminated, appears to be driven mainly by the activity of the Arabian Heat Low (AHL) in the central Sahel, and by the structure of the meridional temperature gradient over the inter-tropical Atlantic in the western Sahel. 展开更多
关键词 Influence of Continental Atmospheric Forcing on the decadal Variability of the West African Monsoon
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Decadence and Mass Culture: The Novel as a Panorama. The Case of Bruges-La-Morte
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作者 Eduard Cairol 《Journal of Literature and Art Studies》 2015年第7期481-494,共14页
Today's idea of the so-called fin-de-sibcle is still somewhat inexact and incomplete. This lack of precision originates from a deeply rooted methodological approach which consists of considering the respective develo... Today's idea of the so-called fin-de-sibcle is still somewhat inexact and incomplete. This lack of precision originates from a deeply rooted methodological approach which consists of considering the respective developments of literature, art, and science in isolation, without paying attention to any interference or reciprocal contamination. This defective method also affects the overlaps and contacts between high culture and popular culture. Despite the progress made over recent years, there are few researchers who approach their objective with a real awareness of the complexity of a time period which saw the appearance of mass culture in the current sense and an unprecedented boom in scientific and technological development.1 To this end, the example of the great German philosopher Walter Benjamin and his studies on Paris during the 19th century----collected in the essays on the great French poet Charles Baudelaire and especially in the monumental and unfinished work The Arcades Project--is, without doubt, a model to follow. Taking the path suggested by Benjamin, this article sets out a revision of the novel Bruges-la-Morte (1892) by the Belgian writer Georges Rodenbach, considered one of the major exponents of thefin-de-sikcle decadence, which goes beyond the usual approach of a symbolist reading, by paying special attention to the frictions between literature and technology on one hand, and between literature and popular entertainment on the other. 展开更多
关键词 fin-de-sircle mass culture Walter Benjamin Georges Rodenbach Bruges-la-Morte SYMBOLISM decadence literature and technology
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Vomunt ut Edant,Edunt ut Vomant:Petronius’Satyricon and Features of Decadence and Victimhood in Sigalit Landau’s Installation“The Dining Hall”
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作者 Nava Sevilla-Sadeh 《Journal of Philosophy Study》 2021年第5期387-416,共30页
Sigalit Landau is an international sculpture,video,installation,and performance artist,born in Jerusalem,and raised also in the USA and the UK.The infernal main space in her installation“The Dining Hall”(2007,KW Ins... Sigalit Landau is an international sculpture,video,installation,and performance artist,born in Jerusalem,and raised also in the USA and the UK.The infernal main space in her installation“The Dining Hall”(2007,KW Institute for Contemporary Art,Berlin)is filled with images resembling human remains engaged in riotous consumption from huge iron pots,in physical circus-like tricks,and copulation,surrounded by huge fleshy-like constructions.While the immediate association may be that of an apocalyptic catastrophe in relation to the Holocaust,the reference is multifaceted,as this study seeks to show.There is a strong connotation of corporeality,gluttony,digestion,decay,and abjection combined with licentiousness,and a proximity between death and pleasure.This multiplicity of contexts is embedded in the term décadence,in its connection with Antiquity and mostly with ancient Rome,and calls to mind the Roman Menippean 1st century CE text Satyricon by Petronius.A comparative analysis of Landau’s installation in relation to Satyricon opens up the way to a broad interpretation,revealing much topical and conceptual parallelism that reveals Landau’s engagement with a kind of decadence typical to the contemporary condition and that of Israel in particular.A prominent feature of her installation is that of victimhood and its influence on the Israeli occupation policy and conduct.Consequently,Landau’s installation is interpreted here as an allegory of a particular state of mind,reflecting both decadence and victimhood. 展开更多
关键词 classical reception studies ABJECTION panem et circenses decadence victimhood HOLOCAUST Israeli occupation policy
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Linkage of the Decadal Variability of Extreme Summer Heat in North China with the IPOD since 1981
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作者 Tiejun XIE Ji WANG +2 位作者 Taichen FENG Ting DING Liang ZHAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第9期1617-1631,共15页
Extreme summer heat can have serious socioeconomic impacts in North China.Here,we explore the decadal variability of the number of extreme heat days in early-to-mid summer(June and July)and a related potential mechani... Extreme summer heat can have serious socioeconomic impacts in North China.Here,we explore the decadal variability of the number of extreme heat days in early-to-mid summer(June and July)and a related potential mechanism consistent with the major seasonal occurrence period of extreme heat events in North China(NCSH).Observational analyses show significant decadal variability in NCSH for 1981–2021,potentially linked to the Indo-Pacific warm pool and Northwest Pacific Ocean dipole(IPOD)in early-to-mid summer.Dynamic diagnostic analysis and the linear baroclinic model(LBM)show that the positive IPOD in early-to-mid summer can excite upward vertical wind anomalies in the South China-East China Sea region,shifting the position of the western Pacific subtropical high(WPSH)to the east or weakening the degree of its control of the South China-East China Sea region,thus generating a positive geopotential height quadrupole(EAWPQ)pattern in the East Asia-Northwest Pacific region.Subsequently,the EAWPQ can cause air compression(expansion)over North China by regulating the tropospheric thickness anomalies in North China,thus increasing(decreasing)NCSH.Finally,an empirical model that incorporates the linear trend can better simulate the decadal NCSH compared to an empirical model based solely on the IPOD index,suggesting that the decadal variability of NCSH may be a combined contribution of the decadal IPOD and external linear forcing. 展开更多
关键词 extreme heat early-mid summer North China Indo-Pacific warm pool and Northwest Pacific Ocean dipole(IPOD) decadal variability
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An Interpretation of Brick's Decadence in Cat on a Hot Tin Roof from the Perspective of Trauma Theory
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作者 陈素 《海外英语》 2018年第14期169-170,共2页
Tennessee Williams is one of the most prominent American dramastists in the twentieth century.Cat on a Hot Tin Roof is his another masterpiece,which won the Pulitzer Prize for Drama in 1955.In the play,the protagonist... Tennessee Williams is one of the most prominent American dramastists in the twentieth century.Cat on a Hot Tin Roof is his another masterpiece,which won the Pulitzer Prize for Drama in 1955.In the play,the protagonist Brick suffers from unbearable psychological traumas,which inevitably results in his decadence.With the analysis of Brick’s decadence from the perspective of the familial trauma,emotional trauma and social trauma,readers will not only gain insights into the unpleasant relationships among family members,but also have a comprehensive understanding of the loneliness and alienation among the individuals in society. 展开更多
关键词 英语 学习方法 阅读
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为“颓废”正名:对中国自身现代性的探寻——兼论《颓废审美风格与晚明现代性研究》
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作者 傅美蓉 《湖北工程学院学报》 2024年第1期31-37,共7页
颓废是一个研究中国现代性的重要概念,在经历了从“颓加荡”到“颓废”的理论旅行之后,在审美风格意义上成为晚明现代性的表征。国内学者对颓废审美风格与晚明现代性的研究,既是探寻中国自身现代性的过程,也是为“颓废”正名的过程。作... 颓废是一个研究中国现代性的重要概念,在经历了从“颓加荡”到“颓废”的理论旅行之后,在审美风格意义上成为晚明现代性的表征。国内学者对颓废审美风格与晚明现代性的研究,既是探寻中国自身现代性的过程,也是为“颓废”正名的过程。作为中国现代性的逻辑起点,晚明颓废审美风格也是中国现代性的文化表征之一。基于晚明现代性研究的理论困境,以颓废话语来阐发晚明现代性,既可晚明为中国现代性逻辑起点的正当性,又明确回答了中国自身现代性的起源问题。 展开更多
关键词 晚明 颓废 现代性
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新时代十年中国粮食安全之路——历程回顾、成效评估与路径展望
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作者 刘华军 丁晓晓 《经济与管理评论》 CSSCI 北大核心 2024年第4期44-57,共14页
保障国家粮食安全是确保经济发展、社会稳定、国家安全的重要基础。聚焦新时代十年这一具有里程碑意义的历史阶段,围绕中国粮食安全的实践历程与重大成就,完整展现新时代十年中国粮食安全之路的发展全貌;结合党的二十大提出的新任务新要... 保障国家粮食安全是确保经济发展、社会稳定、国家安全的重要基础。聚焦新时代十年这一具有里程碑意义的历史阶段,围绕中国粮食安全的实践历程与重大成就,完整展现新时代十年中国粮食安全之路的发展全貌;结合党的二十大提出的新任务新要求,系统展望提高国家粮食安全保障能力的可行路径。研究发现,新时代十年,中国严守18亿亩耕地保护红线,累计建成十亿亩高标准农田,农业科技进步贡献率提高了7.9%,农业生态环境显著改善,以刷新千亿斤粮食新纪录并连续八年稳定在1.3万亿斤以上的佳绩书写了新时代保障粮食安全的伟大实践。新征程上,中国应进一步加强高标准农田质量监管、全力推进大豆抢种扩面、推动种业科技自立自强、加快推进智慧农业发展,为农业强国及社会主义现代化强国建设夯实基础。 展开更多
关键词 党的二十大 新时代十年 粮食安全 农业强国
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ENSO组合模态可预测性的季节-年代际变化 被引量:1
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作者 徐怡然 郑飞 杨若文 《海洋预报》 CSCD 北大核心 2024年第2期83-91,共9页
厄尔尼诺-南方涛动组合模态(C-mode)是厄尔尼诺衰减期西北太平洋上空异常反气旋发展的主要驱动力,通常可以形成水汽输送通道,导致我国南部地区降水增多并发生严重的洪涝灾害,而在拉尼娜期间则情况相反。利用1981—2020年美国国家环境预... 厄尔尼诺-南方涛动组合模态(C-mode)是厄尔尼诺衰减期西北太平洋上空异常反气旋发展的主要驱动力,通常可以形成水汽输送通道,导致我国南部地区降水增多并发生严重的洪涝灾害,而在拉尼娜期间则情况相反。利用1981—2020年美国国家环境预报中心和美国国家大气研究中心再分析数据集的表面风场资料分析了C-mode可预测性的季节-年代际变化。结果表明:C-mode在2000年以后的可预测性明显下降,主要原因是其变率减小、强度减弱、信噪比降低等。在季节尺度上,C-mode存在“秋季预报障碍”,这与信号的季节循环密切关联,当C-mode在秋季进入衰退期时,信号强度最弱、变率最小,因此其秋季的可预测性降低。 展开更多
关键词 ENSO组合模态 C-mode可预测性 季节-年代际
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基于循环神经网络的欧亚中高纬夏季极端高温年代际预测模型研究 被引量:1
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作者 索朗多旦 黄艳艳 +1 位作者 陈雨豪 王会军 《大气科学学报》 CSCD 北大核心 2024年第2期273-283,共11页
近几十年来频繁发生的极端高温事件严重威胁着自然生态系统、社会经济发展和人类生命安全。针对生态环境脆弱的欧亚中高纬地区,首先评估了当前主流动力模式(CMIP6 DCPP)对于该地区夏季极端高温的年代际预测水平,并构建了基于循环神经网... 近几十年来频繁发生的极端高温事件严重威胁着自然生态系统、社会经济发展和人类生命安全。针对生态环境脆弱的欧亚中高纬地区,首先评估了当前主流动力模式(CMIP6 DCPP)对于该地区夏季极端高温的年代际预测水平,并构建了基于循环神经网络(Recurrent Neural Networks,RNN)的年代际预测模型。多模式集合平均(Multi-Model Ensemble,MME)的评估结果显示,得益于大样本和初始化的贡献,当前动力模式对于60°N以南区域(South Eurasia,SEA)展现了预测技巧,准确预测出了其线性增长趋势和1968—2008年间主要的年代际变率,然而模式对于60°N以北区域(North Eurasia,NEA)极端高温的年代际变率几乎没有任何预测技巧,仅预测出比观测低的线性增长趋势。基于86个初始场的动力模式大样本预测结果,RNN将2008—2020年间NEA和SEA极端高温的年代际变率预测技巧显著提高,距平相关系数技巧从MME中的-0.61和-0.03,提升至0.86和0.83,均方差技巧评分从MME中的-1.10和-0.94,提升至0.37和0.52。RNN的实时预测结果表明,在2021—2026年,SEA区域的极端高温将持续增加,2026年很可能发生突破历史极值的极端高温事件,NEA区域在2022年异常偏低,而后将呈现波动上升。 展开更多
关键词 极端高温 DCPP 年代际预测 循环神经网络
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新时代十年青少年和学校体育政策的注意力配置研究——基于“结构要素—决策属性”分析框架 被引量:1
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作者 关清文 张晓林 +2 位作者 杨雅晰 王涛 陈新键 《山东体育学院学报》 北大核心 2024年第1期23-33,共11页
青少年和学校体育政策在指引我国青少年和学校体育高质量发展中发挥着重要的“指挥棒”作用。该研究通过文献资料、文本编码和逻辑推理等方法,在构建“结构要素—决策属性”分析框架的基础上,采用注意力配置理论对新时代十年青少年和学... 青少年和学校体育政策在指引我国青少年和学校体育高质量发展中发挥着重要的“指挥棒”作用。该研究通过文献资料、文本编码和逻辑推理等方法,在构建“结构要素—决策属性”分析框架的基础上,采用注意力配置理论对新时代十年青少年和学校体育政策进行了注意力配置研究。结果显示,新时代十年青少年和学校体育政策存在政策之间互动更强、融入领域更为广泛和压实执行责任更细等特征;政策结构要素维度在目标定位、资源输入、过程内容和评价监管等层面的注意力配置分布各有不同;决策属性维度呈现出不同决策部门的政策注意力配置偏向:中央政府倾向于青少年体育公共服务体系建设、教育部门集中在以学校为阵地的体育教学活动、体育部门偏向于以训练和竞赛为主的体育活动、其他部门更注重以体质和卫生为主的健康行为。 展开更多
关键词 学校体育 青少年体育 政策研究 注意力配置 新时代十年
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黑潮延伸区系泊浮标海表pH的年际和季节变化
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作者 武雨茜 刘聪 +3 位作者 贺双颜 陈栋 姜庆岩 李培良 《海洋科学进展》 CAS CSCD 北大核心 2024年第3期466-477,共12页
西北太平洋海表pH具有显著的长期酸化趋势和季节性变化。近十年来,位于黑潮延伸区的KEO浮标(144°36′E, 32°24′N)提供了丰富的观测数据。基于2008至2019年浮标海表实测盐度、温度、气压和CO_(2)分压数据,利用CO2SYS程序重建... 西北太平洋海表pH具有显著的长期酸化趋势和季节性变化。近十年来,位于黑潮延伸区的KEO浮标(144°36′E, 32°24′N)提供了丰富的观测数据。基于2008至2019年浮标海表实测盐度、温度、气压和CO_(2)分压数据,利用CO2SYS程序重建了近原位海表pH时间序列,并对其年际趋势和季节变化进行了分析讨论。结果表明,KEO站点2008年至2019年海表pH下降速率为(2.18±0.52)×10^(-3)/a,与日本周边海域pH下降速率趋势一致。气候态月平均pH在夏季最小,其季节变化与位于西北太平洋同一纬度的其他两个JMA(Japan Meteorological Agency)站点((137°E, 32°N)和(165°E, 32°N))相似。KEO站点的海表pH季节变化较邻近的近岸CL站点((140°22′E, 35°10′N),位于千叶县)更为显著。KEO站点海表pH最大下降速率发生在夏季(3.22±0.64)×10^(-3)/a,与秋季(2.55±0.44)×10^(-3)/a相当,其次发生在春季(1.89±0.42)×10^(-3)/a,最后在冬季(1.66±0.37)×10^(-3)/a,约为最大值的1/2。本研究所用时间序列较短(小于等于12年)且存在数据缺口,使得趋势计算具有较高不确定性,建议采用更长的时间序列进一步研究海洋酸化的年际和季节趋势差异。本研究有助于加深对黑潮延伸区海洋酸化的认识。 展开更多
关键词 海洋酸化 季节变化 年际变化 KEO 海表pH重建
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阿留申低压与东亚冬季风关系的年代际变化
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作者 杨崧 林楠 张团团 《大气科学学报》 CSCD 北大核心 2024年第2期173-183,共11页
东亚冬季风系统是北半球冬季最活跃的环流系统,通过与西伯利亚高压、阿留申低压、东亚大槽和东亚西风急流等系统之间的相互作用,对东亚地区的气候产生重要影响。本文主要关注阿留申低压与东亚冬季风关系的年代际变化特征,利用经验正交... 东亚冬季风系统是北半球冬季最活跃的环流系统,通过与西伯利亚高压、阿留申低压、东亚大槽和东亚西风急流等系统之间的相互作用,对东亚地区的气候产生重要影响。本文主要关注阿留申低压与东亚冬季风关系的年代际变化特征,利用经验正交函数分析方法,提取阿留申低压的强度变化、南北移动、西北-东南传播型和东西移动模态,并研究这4种模态与冬季风的北部型、南部型模态关系。结果表明阿留申低压的强度变化与2种东亚冬季风型的关系都不显著。阿留申低压的南北移动与南部型冬季风的相关性较强且具有年代际变化特征。1995年后南北涛动中心受ENSO(El Ni1o-Southern Oscillation)影响向东移动,阿留申低压和西伯利亚高压的配置不利于中国东南部气压梯度的形成,导致阿留申低压的南北移动与南部型冬季风的相关性降低。另外,1975年后北大西洋涛动在中西伯利亚地区激发正位势高度异常,扩大传播型模态影响范围,给中高纬地区带来东北风异常,有利于北部型冬季风的形成,此时传播型模态与北部型冬季风显著相关。东亚冬季风系统是北半球冬季最活跃的环流系统,通过与西伯利亚高压、阿留申低压、东亚大槽和东亚西风急流等系统之间的相互作用,对东亚地区的气候产生重要影响。本文主要关注阿留申低压与东亚冬季风关系的年代际变化特征,利用经验正交函数分析方法,提取阿留申低压的强度变化、南北移动、西北-东南传播型和东西移动模态,并研究这4种模态与冬季风的北部型、南部型模态关系。结果表明阿留申低压的强度变化与2种东亚冬季风型的关系都不显著。阿留申低压的南北移动与南部型冬季风的相关性较强且具有年代际变化特征。1995年后南北涛动中心受ENSO(El NinoSouthern Oscillation)影响向东移动,阿留申低压和西伯利亚高压的配置不利于中国东南部气压梯度的形成,导致阿留申低压的南北移动与南部型冬季风的相关性降低。另外,1975年后北大西洋涛动在中西伯利亚地区激发正位势高度异常,扩大传播型模态影响范围,给中高纬地区带来东北风异常,有利于北部型冬季风的形成,此时传播型模态与北部型冬季风显著相关。 展开更多
关键词 东亚冬季风 阿留申低压 年代际变化 ENSO
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海岸带动态演变与韧性研究进展
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作者 朱钰 周嬴涛 +2 位作者 薛玉龙 冯曦 冯卫兵 《广西科学》 CAS 北大核心 2024年第2期205-212,共8页
海岸带作为海陆缓冲地带,长久以来发挥着保护陆域免受海洋灾害影响的重要作用。在遭受灾害带来的外界干扰时(例如风暴、海平面上升、海岸线侵蚀等),海岸带系统具备抵抗、恢复及适应该负面影响的能力,这种与变化环境相适应的能力被称为... 海岸带作为海陆缓冲地带,长久以来发挥着保护陆域免受海洋灾害影响的重要作用。在遭受灾害带来的外界干扰时(例如风暴、海平面上升、海岸线侵蚀等),海岸带系统具备抵抗、恢复及适应该负面影响的能力,这种与变化环境相适应的能力被称为海岸带韧性。然而人类文明发展以来,长期大规模的干扰活动削弱了海岸带韧性,破坏了海岸带动态演变过程中动力地貌的平衡。因此,本文从海岸带地貌演变的特征展开,总结现有的海岸带侵蚀机理研究成果,指出研究方法中存在的问题和不足,并对目前热点的海岸带韧性与灾后恢复机理研究进展进行梳理,同时结合近年来新兴研究方向指出现有研究内容的不足之处,最后展望了“海洋十年行动计划”背景下海岸带综合开发与管理的研究趋势。 展开更多
关键词 海岸带 海岸带韧性 海岸地貌演变 动态平衡 海洋十年行动计划
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2010年-2020年西安市景观格局变化及其生态效应研究
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作者 刘哲 马新萍 《环境科学与管理》 CAS 2024年第2期153-157,共5页
选取2010年、2020年西安市地表覆盖数据,利用3S技术和景观生态学理论,分析城市景观格局变化及其生态效应。结论:2010年-2020年,西安市以秦岭林地、关中农田地景观为主的大背景格局未发生变化,城市空间连接度提高,多样性提高,区域空间格... 选取2010年、2020年西安市地表覆盖数据,利用3S技术和景观生态学理论,分析城市景观格局变化及其生态效应。结论:2010年-2020年,西安市以秦岭林地、关中农田地景观为主的大背景格局未发生变化,城市空间连接度提高,多样性提高,区域空间格局得到优化。城市新区使水源涵养、娱乐文化功能服务价值提升,食物生产功能服务价值损失较明显,其他生态功能服务价值损失不足1%。在生态红线管控下,城市建设有效保障区域生态功能服务价值整体处于动态平衡。“北跨”时代,城市建设过程中可增加生态景观比重和空间分布,进一步提高西安市生态系统服务功能价值。 展开更多
关键词 10年 西安市 景观格局 生态服务价值
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新时代十年我国意识形态安全的研究动向——基于Cite Space的可视化分析 被引量:1
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作者 张楚 《太原理工大学学报(社会科学版)》 2024年第2期40-49,共10页
党的十八大以来,中国正处于大发展大变革大调整时期,学界围绕意识形态安全相关问题展开研究并取得了多方面的重要成就。通过对2012年以来收录于中国知网(CNKI)且期刊所属类别为CSSCI的共计2148篇文献进行量化与可视化分析,便于直观了解... 党的十八大以来,中国正处于大发展大变革大调整时期,学界围绕意识形态安全相关问题展开研究并取得了多方面的重要成就。通过对2012年以来收录于中国知网(CNKI)且期刊所属类别为CSSCI的共计2148篇文献进行量化与可视化分析,便于直观了解意识形态安全研究现状;对关键词进行聚类分析和绘制关键词共现时序图谱,能够科学、有效地把握新时代十年我国意识形态安全研究的前沿热点和演进趋势。分析发现,新时代十年我国意识形态安全研究极具拓展性、关联性和时代性,但在研究方法、研究思路和研究原则上还有待进一步完善。 展开更多
关键词 新时代十年 意识形态安全 可视化分析 研究动向
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