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1.
黄河断流的气候因子分析 总被引：3，自引：1，他引：3
黄河断流存在人为和自然两方面的综合原因, 其中自然因素中又以气候为主要影响因子。本文利用1951年~1999年近百个站点的温度、降水资料，采用泰森多边形法计算了黄河上、中、下游各流域的面雨量和温度，对黄河流域近50年来温度、降水的气候特征进行了分析；根据1920年--1999年近40个站点的温度和降水资料，讨论了温度、降水与黄河断流的关系。结果表明：1922年--1932年气温较高，降水量偏少是造成黄河流域对应时段连续枯水的主要气候原因；最近二、三十年以来的黄河断流，除了温度和降水等气候因子的影响外，人类对黄河水资源不合理的开发利用以及黄河流域生态环境的恶化等因素均具有不可忽视的重要影响。 相似文献
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2003年梅雨期湿位涡异常诊断分析 总被引：6，自引：0，他引：6
利用 的NCEP/NCAR格点分析资料和中国区域站点观测降水资料，在分析2003年江淮流域梅雨期降水及大尺度环流特征的基础上，利用包含降水质量强迫效应的湿位涡方程，阐明在暴雨系统中引起的强降水会造成湿位涡异常。对2003年引起江淮流域暴雨的对流系统进行的湿位涡诊断分析表明，对流层中低层的湿位涡异常区与降水区域有很好的对应关系，可利用湿位涡的异常分布预测降水未来可能的分布形势和走向。 相似文献
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本文使用全国160站逐月降水资料及NCEP/NCAR再分析资料月平均数据集,采用滑动平均和合成分析方法,分析了江淮流域24个代表站1951-2012年夏季雨量的年代际变化特征.结果表明,近60年来江淮地区夏季降水存在明显的年代际变化特征。通过对西太平洋副热带高压的合成分析,发现江淮流域梅雨期雨量与西太平洋副热带高压关系密切。主要表现为,当副高位置偏西强度偏大时,江淮地区夏季雨量增多;反之,则雨量偏少。 相似文献
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降水集中度和集中期能定量地表征降水量在时空场上的非均匀性。运用淠河流域12个雨量站点1956年-2010年的逐日降水资料,基于降水集中度和集中期分析了淠河流域近55年来汛期降水的时空特征和变化规律。研究结果表明：淠河流域汛期降水集中度变化于0.69~0.11之间,多年平均值0.31,多年平均降水集中期在40~41候。汛期降水量和集中度呈比较显著的上升趋势,增大了汛期发生洪涝灾害的风险。汛期降水量和降水集中度分别在1983年、1962年发生增多突变,集中期无明显突变。汛期降水量、集中度和集中期序列近55年来都具有显著的3~4年周期振荡。汛期降水量和集中度呈比较显著的正相关,和降水集中期呈微弱负相关,即降水量越大,降水越集中,最大降水量出现的日期越有可能提前。 相似文献
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石羊河流域主要气象要素及径流变化趋势分析 总被引：12，自引：0，他引：12
在对石羊河流域1956年~2003年诸月与年平均气温、降水及径流资料进行Mann-Kendall非参数统计检验的基础上,运用R/S法分析了流域的年平均气温、降水、径流时间序列的持续性,估算了各项指标的Hurst指数,以定量估计未来气候及径流的变化趋势,并采用随机重排法对估算结果进行了稳定性检验。结果表明:石羊河流域1956年~2003年各月及年平均气温绝大多数都以增温为主;武威和永昌两个站点的年平均降水表现为显著增加,其他站点各月没有显著趋势;古浪河和杂木河年平均径流量减少的趋势显著,其他支流径流量减少趋势不明显;干流各月及年平均径流量减少的趋势十分显著。各站点Hurst指数结果表明,石羊河流域未来的气温、降水、径流变化趋势都表现为较强的持续性,与过去近48年的变化趋势基本保持一致。 相似文献
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利用淮河流域1960-2008年141个气象站的日降水资料,以及王家坝和吴家渡水文站的日实测流量资料,分析研究时段内淮河流域面雨量时空变化特征及水文站实测径流量的响应,初步探讨实测径流量与降水的相关关系。结果表明,1960-2008年淮河流域面雨量呈增加趋势,但增加趋势不显著。淮河流域面雨量年内分配极不均匀,有显著的季节变化,且年际变幅大,区域差异明显。与面雨量相对应,淮河中上游主要水文站实测径流量存在明显年际震荡,这种年际差异在淮河中游更为显著,水资源更加不稳定。近50年来淮河中上游径流量变化趋势和其汇水区域面雨量变化趋势基本一致,两者呈显著的正相关,降水是影响该区域实测径流的一个重要因素,人类活动对实测径流的影响不明显。 相似文献
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采用1981-2010年汛期逐日降水资料、NCEP再分析资料及地形资料,对三江流域汛期暴雨进行天气学分型,选取典型个例对强降水落区与地形进行天气学分析。结果表明:三江流域主要暴雨天气型有:高空槽东移型、暖切变型、冷切变型、低涡东移型、台风影响型,各类型暴雨在各月分布差异较大;高空槽型降水大值点基本都在槽南侧辐合条件最好、且西南气流辐合条件最好的地点;冷切变型和暖切变型降水大值点在切变南侧西南气流辐合条件较好,且西南气流与地形夹角较大站点,低涡型暴雨降水大值点处在低涡南侧或低涡中心附近,西南气流与地形夹角较大站点,台风影响型暴雨由于台风自身云系深厚,螺旋云带区域降水量较大,大值点一般在与台风东部象限风向交角最大站点;地形引起的上升速度使得对流发展引起降水,也能够作为中小尺度的强对流系统的触发机制,造成不稳定能量的释放,在山区的迎风坡暴雨频次数增加,暴雨量增大;利用vb语言开发暴雨个例显示平台,对暴雨研究与预报有重要意义。 相似文献
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黄河上游地区云层特征与降水关系的分析 总被引：2，自引：0，他引：2
应用１９９２－１９９６年４－９月黄河上游河曲段部分气象站逐日０２、０８、１４、２０点云量和云状、２０－０８点、０８－２０点降水资料,计算分析了４－９月黄河上游河曲地区主要降水云层。对流云和层状层的云层特征,出现效率、地理分布及其与降水的关系。结果表明,黄河上游河曲地区４－９月层状云出现频率的１５％,其≥０．１ｍｍ降水率的５０％,地理分布以久治为高值中心,由南向北呈递减趋势。对流云出现频率的６０％、 相似文献
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《内蒙古科技与经济》2016,(2)
对锡林郭勒盟(简称锡盟)2014年5月9日~11日降水天气过程的人工增雨作业条件及降水天气系统对人工增雨作业效率的影响进行了分析。结果表明,人工增雨作业必须在一定的天气系统条件下进行,合理把握时机和科学作业是提高增雨效益的关键。此次降水过程,高空环流形势有利于增雨作业的实施;同时从探空资料和云图来看:0℃层高度、低层适宜的风速风向、大范围中低云层的覆盖也是有利于飞机增雨作业的开展。自动雨量站实时雨量资料对作业过程的监测、指挥、效果检验方面发挥了重要作用。 相似文献
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《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
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《中国科学院院刊(英文版)》2008,22(1):13-14
Aresearch project on the greenhouse cultivation of Swertia chirayita Buch Ham, a popular herbal drug used by the Tibetan people against liver and gallbladder diseases, recently passed the acceptance check by a panel of experts under the auspices of Qinghai Provincial S＆T Bureau. The feat was accomplished by researchers from the Lanzhoubased CAS Northwest Institute of Plateau Biology. 相似文献
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The research into the origins of domestic animals is of significance not only for understanding their development per se but also for making clear the human society evolution. Although there are evidences to show that pigs were independently domesticated in a variety of places throughout the world the detailed scenario of the origin dispersal of domestic pigs in East Asia remains unclear.…… 《中国科学院院刊(英文版)》2008,22(1):7-7
The research into the origins of domestic animals is of significance not only for understanding their development per se, but also for making clear the human society evolution. Although there are evidences to show that pigs were independently domesticated in a variety of places throughout the world, the detailed scenario of the origin and dispersal of domestic pigs in East Asia remains unclear. 相似文献
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Among the galaxy of research development organizations in northwest Beijing's Zhongguancun district known as China's Silicon Valley two are especially well-known to IT researchers: Microsoft Research Asia 《中国科学院院刊(英文版)》2008,22(1):47-49
Among the galaxy of research and development organizations in northwest Beijing＇s Zhongguancun district, known as China＇s Silicon Valley, two are especially well-known to IT researchers： Microsoft Research Asia （MSRA）, and, within a few blocks on the other side of the street, the CAS Institute of Automation （CASIA）. While most people in Chinese scientific organizations strive to move to a large foreign counterpart, Dr. Stan Z. Li （LI Ziqing） moves against the stream. 相似文献
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《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
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《中国科学院院刊(英文版)》2008,22(1):58-58
As a key component of the national initiative for basic S＆T data and infrastructure development, a nationwide survey on the lake water quality, volume and bio-resources has recently been kicked off. The move marks the systematic implementation of the secondround investigation of the country＇s lacustrine resources. 相似文献
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Bats the only mammals known to possess the real ability to fly have fascinated zoologists for a long time with their long-distance migration. How do they find their way home from an altitude of kilometers above sea level where their stunt of ultrasonic echolocation does not work?…… 《中国科学院院刊(英文版)》2008,22(1):3-4
Bats, the only mammals known to possess the real ability to fly, have fascinated zoologists for a long time with their long-distance migration. How do they find their way home from an altitude of kilometers above sea level, where their stunt of ultrasonic echolocation does not work？ Recent discoveries supported the theory that bats might be able to use magnetic clues to figure out their own position,just like what birds do. However, the latest results from a joint study by a group of researchers from the CAS, East China Normal University and University of Auckland reveal that bats apply an interesting strategy different from the one underlying birds＇ orientation technique, though they both are believed to derive information about their position from the subtle changes in the magnetic field of the Earth. 相似文献
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《中国科学院院刊(英文版)》2014,(3):252-252
<正>On February 12,2014,the international academic journal Cancer Research published an article online entitled"Latency Associated Nuclear Antigen of Kaposi's Sarcoma Associated Herpesvirus Promotes Angiogenesis through Targeting Notch Signaling Effector Hey1",as a result from the research conducted by Prof.LAN Ke’s lab at the Institut Pasteur of Shanghai,Chinese Academy of Sciences. 相似文献
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SONG Jianlan 《中国科学院院刊(英文版)》2014,(3):217-220
<正>Scientists from CAS and the Max Planck Society(MPG)met on May 13,2014 in Beijing to celebrate their four-decade-long ST cooperation and cherished friendship,anticipating further development of the bilateral relation.This partnership formally began four decades ago with a visit paid by then MPG President,Prof.Lüst to CAS,introduced CAS President BAI in his address at the celebration:"During the visit,CAS and MPG confi rmed the basic principles of cooperation,that is equality and mutual benefi ts for both sides,and reached agreement to develop a collaborative partnership."This occurred only two years after the establishment of the diplomatic relations between Germany and China,despite the shadow of the Cold War."Building up a partnership between Germany and 相似文献
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TANG Kun 《中国科学院院刊(英文版)》2014,(2):161-165
<正>The scientifi c goals of the Partner Group are to utilize large scale genomic polymorphism data to make fi ne inferences about human demographic history and various forms of natural selection in the human genome;and to understand the genetic basis and evolutionary mechanisms underlying the common variations in human facial morphology,both within and between populations. 相似文献