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1.
引 言  众所周知,多普勒雷达只能测得径向速度,要获得水平风矢量场,必须用两部或三部雷达同时测量。由于多普勒雷达价格昂贵,不少气象工作者致力于从单部多普勒雷达提取水平风场信息。Waldteufel和Carbin提出了VVP(VolumeVelocityP?..  相似文献   

2.
ImprovingtheVorticity-StreamfunctionMethodtoSolveTwo-DimensionalAnelasticandNonhydrostaticModelSunLitan(孙立潭)andHuangMeiyuan(黄...  相似文献   

3.
窦贤康 Scial.  G 《大气科学》1997,21(3):348-356
多重解析多普勒方法是用解析表达式进行三维风场反演。它成功地应用于处理地基多普勒雷达资料,获取对流系统层状降水区域的风场结构,本文将MANDOP方法在机载雷达情况下的进行推广并通过模拟研究径向速度测量中信号噪声、雨滴降落速度估计误差,尤其是由于机载特性的引入产生的雷达束定位误差等对方法的影响。模拟结果显示,在机载雷达的技术参数下,MANDOP方法能够提供误差可以接受的三维风场反演。这为利用MANDO  相似文献   

4.
The regional dynamical model of the atmospheric ozonosphere   总被引:1,自引:0,他引:1  
TheRegionalDynamicalModeloftheAtmosphericOzonosphereWangWeiguo(王卫国),XieYingqi(谢应齐)DepartmentofEarthscience.YunnanUniversity,K...  相似文献   

5.
A Bogus Typhoon Scheme and Its Application to a Movable Nested Mesh Model   总被引:1,自引:0,他引:1  
ABogusTyphoonSchemeandItsApplicationtoaMovableNestedMeshModelWangGuomin(王国民)(DepartmentofAtmosphericSciences,NamingUniversity...  相似文献   

6.
Propagation of Envelope Solitons in Baroclinic Atmosphere   总被引:1,自引:0,他引:1  
PropagationofEnvelopeSolitonsinBaroclinicAtmosphere¥TanBenkui(谭本馗)(DepartmentofGeophysics,PekingUniversity,Beijing100871)YinD...  相似文献   

7.
单多普勒风场反演若干技术和进展   总被引:2,自引:1,他引:2  
雷茂生 《气象科技》2000,28(3):19-21,45
该文详细地总结了目前国内外针对单多普勒天气雷达风场资料提出的反演风场的若干技术和发展动态,从中可以了解到目前普勒雷达的最新风场反演技术-变分资料同化VDA技术和这种技术的若干实现方法及其特点。  相似文献   

8.
ADiagnosticStudyofMoistPotentialVorticityGenerationinanExtratropicalCyclone①ZuohaoCaoandG.W.K.MoreDepartmentofPhysics,Univers...  相似文献   

9.
OBSERVATIONFORTOGA-COAREANDRELEVANTRESEARCHLiJi(李骥),LuEr(陆尔)andDingYihui(丁一汇)CenterforClimaticResearchI.REPORTONTOGAOBSERVATI...  相似文献   

10.
TheInfluenceofTibetanPlateauontheInterannualVariabilityofAsianMonsoon①WuAiming(吴爱明)andNiYunqi(倪允琪)DepartmentofAtmosphericScie...  相似文献   

11.
12.
一次东北冷涡暴雨过程的数值模拟试验   总被引:7,自引:6,他引:7       下载免费PDF全文
姜学恭  孙永刚  沈建国 《气象》2001,27(1):25-30
利用MM5非静力模式成功地模拟了1998年8月8-9日一次东北冷涡切变型暴雨过程。发现本次过程中,低涡西北象限的强降水中心的产生是由于高层形成的强辐散,切变降水的产生由于偏南急流与偏东急流的交汇,切变带上升运动层明显低于低涡。同时,通过对比试验发现,偏南急流是本次过程主要水汽输送带。且对切变降水影响较大。偏南急流区水汽的减弱对系统(低涡、切变)的降水强弱有直接影响;西路冷空气加强主要使大气斜压作用增强导致低涡强度及降水增强;东路冷空气主要通过阻挡偏南气流形成抬升从而主要影响切变强度和降水。阻高则通过对上游低值系统的阻挡影响其位置和强度进而影响过程降水。  相似文献   

13.
本文根据FGGE3B资料得到的基本物理量场如u—v分量、温度、湿度、散度、涡度、垂直运动等,对南亚一次强季风槽—ITCZ发展与维持作了较详细的分析,并就高空东风急流对扰动形成的影响以及两个季风体系中天气系统的相互作用作了讨论。   相似文献   

14.
A new solution is presented to the problem ofrelating source strength and concentration profiles within a plant canopy. The solution is based on the Lagrangian dispersion theory developed by G. I. Taylor in 1921. A dispersion matrix is derived that relates the source and concentration profiles based on profiles of the turbulent length and velocity scales. The matrix translates the effects of persistence (a temporal effect) into spatialcoordinates and represents the change from near-field to far-field in acontinuous fashion, successfully accounting for both regimes. A test ofthe new model using wind-tunnel data showed excellent quantitative agreement between model and measurements. A comparison was also made withM. R. Raupach's localized near-field theory, which underestimated the near-field effect in the wind-tunnel data and relative to the new model.  相似文献   

15.
Lightning and climate: A review   总被引:4,自引:0,他引:4  
Research on regional and global lightning activity and the global electrical circuit is summarized. This area of activity has greatly expanded through observations of lightning by satellite and through increased use of the natural (Schumann) resonances of the Earth–ionosphere cavity. The global electrical circuit provides a natural framework for monitoring global change on many time scales. Lightning is responsive to temperature on many time scales, but the sensitivity to temperature appears to diminish at the longer time scales.  相似文献   

16.
A large-eddy simulation is modified to include multiple scalars emitted by a plant canopy. Each of these scalars is subjected to varying rates of chemical loss. Presented is a detailed comparison between conservedspecies and species undergoing first- and second-order chemical loss.Profiles of mean mixing ratio, mixing-ratio variance and vertical mixing-ratio flux reveal the influence of chemical reactivity. Distribution of thescalar source through the depth of the canopy is shown to locally reducethe reaction rate for second-order species. Transport efficiencies, diffusioncoefficients, and mean source heights also exhibit chemical dependencies.Budgets of mixing-ratio variance and flux elucidate the mechanisms throughwhich chemistry modifies each. Instantaneous fields show the existence ofintermittently occurring coherent structures that are thought to enhancespecies segregation.  相似文献   

17.
典型超级单体风暴过程分析   总被引:10,自引:2,他引:8  
牛淑贞 《气象》1999,25(12):32-37
利用郑州714CD多普勒天气雷达观测资料,结合有关地面要素资料和郑州探空资料,对1998年9月4日一次典型超级单体造成的冰雹大风和短时强降水过程进行分析探讨,揭示了强对流天气雷达回波强度场和多普勒速度场的典型特征,为强对流天气的监测、识别、临近预报和人工消雹提供参考。  相似文献   

18.
Abstract

The sensitivity of the annual cycle of ice cover in Baffin Bay to short‐wave radiation is investigated. The Princeton Ocean Model (POM) is used and is coupled with a multi‐category, dynamic‐thermodynamic sea‐ice model in which the surface energy balance governs the growth rates of ice of varying thickness. During spring and summer the short‐wave radiation flux dominates other surface heat fluxes and thus has the greatest effect on the ice melt. The sensitivity of model results to short‐wave radiation is tested using several, commonly used, shortwave parameterizations under climatological, as well as short‐term, atmospheric forcing. The focus of this paper is short‐term and annual variability. It is shown that simulated ice cover is sensitive to the short‐wave radiation formulation during the melting phase. For the Baffin Bay simulation, the differences in the resulting ice area and volume, integrated from May to November, can be as large as 45% and 70%, respectively. The parameterization of the effect of cloud cover on the short‐wave radiation can result in the sea‐ice area and volume changes reaching 20% and 30%, respectively. The variation of the cloud amount represents cloud data error, and has a relatively small effect (less then ±4%) on the simulated ice conditions. This is due to the fact that the effect of cloud cover on the short‐wave radiation flux is largely compensated for by its effect on the net near‐surface long‐wave radiation flux.  相似文献   

19.
20.
The Dirt Hills, located roughly forty miles to the southwest of the Regina Weather Office, at Regina, Saskatchewan, were clearly visible on the horizon in the early morning of the 29th day of August 1972 from the Regina Weather Office. This mirage was documented and a picture of it was taken.  相似文献   

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