民主德国各种天气预报模式效果的比较     

Г-И.杰利错哥  王京泰 《气象科技》1986,(2):29-32

引论这篇文章的目的是介绍民主德国气象服务中在大气动力学模拟和建立短期天气预报模式方面的情况。为此,对各种类型的模式进行了比较。必须注意的是,在最近十年中我们的工作与苏联有关的水文气象中心紧密联系在一起。从七十年代开始,在气象服务中日常业务的数值天气预报已经变为现实。除了过滤模式以外,也使用了边值随时间变化的原始方程(PE)模式。  相似文献   

对“浙江长兴二叠系-三叠系界线层型剖面面临的新问题”一文的商榷     

中国地质大学二叠系-三叠系界线工作组 《地层学杂志》2008,32(2):227-229

承蒙<地层学杂志>编辑部寄来王成源先生"浙江长兴二叠系-三叠系界线层型剖面面临的新问题"一文(以下简称王文)征求意见,兹将我们对其2、3两段的意见表述如下,供大家讨论:  相似文献   

植被指数差异在干旱遥感监测中的应用   总被引：6，自引：0，他引：6       下载免费PDF全文

李星敏-刘安麟  王钊  邓凤东  卓静 《陕西气象》2004,(5):17-19

利用2001、2002年春季降水和土壤墒情及NOAA／AVHRR气象卫星资料，分析了不同年的植被指数差异与同期降水量和土壤相对湿度差异的关系，结果表明，年际间植被指数的差异可以明显地反映作物受早程度的差异，此方法可以用来定性地分析年际间的干旱程度和受早范围。  相似文献   

GOCE卫星数据的效益还在持续     

自然-科学报告 《气象知识》2019,(1):33-33

2009—2013年间在轨运行的GOCE(地球重力场和海洋环流探测器)卫星似乎已经淡出科学界的视线,然而,这颗曾经以前所未有的精确度绘制了地球重力场的卫星,对其数据的分析帮助科学家发现南极东部冰盖下存在古老的稳定地块,并且可以与过去相邻的印度和澳大利亚连接起来,是所谓“消失的大陆”。  相似文献   

法国罗纳河及其流域整治     

让-保罗·布拉瓦尔  蔡宗夏 《世界地理研究》2015,(1):11-18

罗纳河历史上曾经是欧洲的一条典型的"野性"河流,洪水汹涌,桀骜不驯。后来,它又成了一条为法国近代的工业革命和现代经济发展作出重大贡献的"驯服"的河流。在500多公里的河段,建造了20多座水电站,为河流水电站梯级开发之"世界之最"。然而,自从1980年代以来,随着法国能源政策转向大力发展核电,水电站梯级开发时代的结束,环境保护的呼声日益高涨,罗纳河的整治逐渐进入以自然生态环境的恢复和保护为中心的持续发展时代。人们开始拆除水坝和河堤,恢复河漫滩湿地,等等。在这人与河流复杂的相互关系的历史中,河流流域整治的观念,政策都发生了巨大的变化,整治的科技手段也有了很大的进步。罗纳河流域整治以"健康河流"和"河流健康"为中心的发展战略,为中国河流流域整治提供了值得借鉴的经验。  相似文献   

GSTARS computer models and their applications, part I： theoretical development   总被引：1，自引：1，他引：0  

Chih Ted YANG  Francisco J. M. SIMES Borland Prof. of Water Resources  Director of Hydroscience  Training Center  Department of Civil  Environmental Engineering  Colorado State University  Fort Collins  CO -  U. S. A.  Research Hydrologist  US Geological Survey  Geomorphology  Sediment Transport Laboratory  Technology Drive  Suite  Golden  CO  U. S. A. 《国际泥沙研究》2008,23(3):197-211

GSTARS is a series of computer models developed by the U.S. Bureau of Reclamation for alluvial river and reservoir sedimentation studies while the authors were employed by that agency. The first version of GSTARS was released in 1986 using Fortran IV for mainframe computers. GSTARS 2.0 was released in 1998 for personal computer application with most of the code in the original GSTARS revised, improved, and expanded using Fortran IV/77. GSTARS 2.1 is an improved and revised GSTARS 2.0 with graphical user interface. The unique features of all GSTARS models are the conjunctive use of the stream tube concept and of the minimum stream power theory. The application of minimum stream power theory allows the determination of optimum channel geometry with variable channel width and cross-sectional shape. The use of the stream tube concept enables the simulation of river hydraulics using one-dimensional numerical solutions to obtain a semi-two- dimensional presentation of the hydraulic conditions along and across an alluvial channel. According to the stream tube concept, no water or sediment particles can cross the walls of stream tubes, which is valid for many natural rivers. At and near sharp bends, however, sediment particles may cross the boundaries of stream tubes. GSTARS3, based on FORTRAN 90/95, addresses this phenomenon and further expands the capabilities of GSTARS 2.1 for cohesive and non-cohesive sediment transport in rivers and reservoirs. This paper presents the concepts, methods, and techniques used to develop the GSTARS series of computer models, especially GSTARS3.  相似文献   

CONTRIBUTIONS OF TUNNEL EROSION TO SEDIMENT YIELD IN A SEMI-ARID BASIN IN THE LOESS PLATEAU OF CHINA     

T.X. ZHU  Q.G. CAI  S.H.LUK Dr.  Department of Geography  University of Minnesota-Duluth  Duluth  MN  USA. Tel: --. Fax: --. Email: tzhu@d.umn.edu Researcher  Institute of Geography  Chinese Academy of Sciences  Beijing   《国际泥沙研究》2000,(4)

1 INTRODUCTIONSubsurface erosion has been increasingly recognized as a significant hillslope geomorphologic process(Carson and ~y, 1972; McCaig, 1983;, Harvey, 1982;Bryan and Harvey, 1985; Crouch andMcGarrity, 1986; Walsh and Howeds, 1988). However, most of the studies were conducted in hubedareas, especially in Britain (e.g. Gilman and Newson, 1980; Jones, 1981; Wilson and Small, 1984; Jones,1987; Jones et al, 1997). Jones and Crane (1984) found that soil piping contributes about …  相似文献   

WOODY VEGETATION AND DEBRIS FOR IN-CHANNEL SEDIMENT CONTROL     

F. Douglas Shields  Jr.  C. M. Cooper 《国际泥沙研究》2000,(1)

lINTRODUCTlONChanne1erosionandsedimentationareoftenproblemsinagriculturalwatersheds.Forexample,annualsuspendedsedimentyieldfrom8mixedcoverwatershedswithloessialsoilsinnorthwesternMississippi,U.S.A.ranginginsizetYom2lto622km2wasbetween7O4and1673tonnes(Shieldsetal.l995).ControlofchannelbankerosionintheU.S.hastraditionaIlybeenaddressedwithstructurescostingontheorderof$l5Om-1ofbankline.BecauseoftheecologicaIvalueandoftenlowercost(relativetononlivingstructure)ofvegetativetreatments,weargue…  相似文献   

Characteristics of Intraslab Stress Field and Tectonic Implication in the Nankai Trough, Japan     

XU Jiren  ZHAO Zhixin Institute of Geology  Chinese Academy of Geological Science  Beijing  China Kono Yoshiteru Faculty of Science  Kanazawa University  Kanazawa -  Japan 《Continental Dynamics》2000,(1)

1. IntroductionThe Nankai Trough region (Fig. 1.1) of southwest Japan is one of the most tectonically complex subduction zones in the world. The subduction of the Philippine Sea plate (PH) beneath the Eurasian plate (EU) has caused a series of large and great interplate earthquakes. It is generally accepted that great earthquakes have occurred at intervals of 100-150 years along the Nankai subduction zone since the 684 Hakuho earthquake (Fig. 1.2). However, a large earthquake (M>7.5) has…  相似文献   

RESERVOIR SEDIMENTATION: RESEARCH NEEDS AND REFOCUSING PERSPECTIVES     

Rollin H. HOTCHKISS 《国际泥沙研究》1999,(2)

IINTRODUCTIONReservoirsedimentationisannuallydecreasingconstT[lctedworldwidewaterstoragebyanestimatedonepercent(Mahmood,1987).Lossesinaridregionsaredoubled,reducingtheaverageusefulreservoirlifeto20-30years(Bruk,1996).Atthisrateofstorageloss,hydroelectricityasanenergysourcecanhardlybecalledrenewable(Nordin,1993).Reservoirsaregenerallyfillingwithsedimentmorerapidlythananticipated.Forexample,datafromindiaindicatethataCtllalsedimentdeliveryishigherthanpredictedin24of27reservoirs,rangingfro…  相似文献