SOME NEW UNDERSTANDINGS OF LAND-SURFACE PROCESSES IN ARID AREA FROM THE HEIFE     

胡隐樵  高由禧 《Acta Meteorologica Sinica》1996,(2)

The survey for the HEIFE(Atmosphere-Land Surface Processes Experiment at Heihe RiverBasin,Western China)is given in the paper.The following basic subjects for land-surface process-es in arid areas are studied:(1)the general characteristics of the energy budget on ground surfacein arid areas;(2)the parameterization of the land surface processes;(3)the interaction betweenoasis and its desert circumstances,a special phenomenon in arid areas.The analysis shows that thesensible heat flux in the surface energy budget is in the majority,and the latent heat flux may beneglected.The influence of atmospheric stratification stability on the turbulent transfer of energyand substance must be considered in parameterization of land surface processes in arid areas.The“cold island effect”phenomenon in oasis and the“humidity inversion”phenomenon in desert nearoasis are the result of the interaction between them.The results would improve the understandingof land surface processes in arid areas.  相似文献   

气旋爆发性发展过程的动力特征及能量学研究   总被引：19，自引：3，他引：19  

吕筱英  孙淑清 《大气科学》1996,20(1):90-100

本文对不同路径的爆发性气旋进行了动力特征及能量学研究。发现高空大值位涡空气的下伸是气旋爆发性发展的一个重要条件。初生气旋逐渐向强位涡区移近并形成上下位涡区相接的形势。使气旋迅速发展。高空急流与气旋发展有密切关系。发展中的气旋明显地向着急流左侧的辐散区移动。急流的突然加强及高空强风动量的不断下传，构成了下层的强风带及上下一致的急流结构。能量学研究指出在气旋发展前气旋内散度风动能向旋转风动能的转换突然增强。散度风动能在爆发气旋发展时有明显增长。  相似文献   

THE CHARACTERS OF ENERGY BUDGET ON THE GOBI AND DESERT SURFACE IN HEXI REGION   总被引：23，自引：0，他引：23       下载免费PDF全文

胡隐樵  杨选利  张强  左洪超 《Acta Meteorologica Sinica》1992,(1)

In the paper,the characters of surface energy budget on Huayin(Gobi)and the desert surface during the periodfrom 26 June to 31 August 1990 in the HEIFE have been analyzed,then have been compared with the observed resultsduring 4—19 September 1988 in the Pilot Observation Period of the HEIFE.The results show that the atmosphere is insuperadiabatic unstable state and there is a phenomenon of inverse humidity to form negative water vapour flux.Thesensible heat flux on the surface energy budget is in majority,but the latent heat flux may be neglected over the Gobi anddesert surface in the cloudless daytime in the summer.  相似文献   

THE CHARACTERS OF ENERGY BUDGET ON THE GOBI AND DESERT SURFACE IN HEXI REGION^*          下载免费PDF全文

Hu Yinqiao  Yang Xuanli  Zhang Qiang  Zuo Hongchao 《Acta Meteorologica Sinica》1992,6(1):82-91

In the paper,the characters of surface energy budget on Huayin(Gobi)and the desert surface during the period from 26 June to 31 August 1990 in the HEIFE have been analyzed,then have been compared with the observed results during 4-19 September 1988 in the Pilot Observation Period of the HEIFE.The results show that the atmosphere is in superadiabatic unstable state and there is a phenomenon of inverse humidity to form negative water vapour flux.The sensible heat flux on the surface energy budget is in majority,but the latent heat flux may be neglected over the Gobi and desert surface in the cloudless daytime in the summer.  相似文献   

夏季青藏高原热力场和环流场的诊断分析 Ⅰ.盛夏高原西部地区的水汽状况   总被引：2，自引：0，他引：2  

杨伟愚  叶笃正  吴国雄 《大气科学》1992,(1)

本文使用青藏高原气象科学实验测站观测资料、欧洲中心FGGE-Ⅲb资料、GMS1地球同步卫星云图资料、河流水文资料以及其他一些有关的资料,详细分析了1979年7月青藏高原地区,尤其是高原西部地区的水汽状况、水汽输入的通道,讨论了夏季青藏高原地区高湿状况的维持机制. 通过研究,发现在1979年盛夏青藏高原西部也是一个高水汽区域,有利于大量的湿对流系统活动,但西部比东南部的水汽含量要略低些;潜热加热是夏季高原西部重要的热源之一;除了过去已知的在高原东南和仲巴、定日一带的两条水汽通道外,水汽还可从高原西侧边界进入高原西部.在讨论夏季高原地区高湿状况的维持机制时发现,相对于高原东部,只需要较少的水汽输入就足以维持高原西部大气的高湿状态;高原西部的降水、蒸发和向土壤中渗透是接近于平衡的,水分循环主要是局地的内循环.  相似文献   

Floodplain storage of mine tailings in the belle fourche river system: A sediment budget approach     

Donna C. Marron 《地球表面变化过程与地形》1992,17(7):675-685

Arsenic-contaminated mine tailings that were discharged into Whitewood Creek at Lead, South Dakota, from 1876 to 1978, were deposited along the floodplains of Whitewood Creek and the Belle Fourche River. The resulting arsenic-contaminated floodplain deposit consists mostly of overbank sediments and filled abandoned meanders along White-wood Creek, and overbank and point-bar sediments along the Belle Fourche River. Arsenic concentrations of the contaminated sediments indicate the degree of dilution of mine tailings by uncontaminated alluvium. About 13 per cent of the 110 × 10⁶ Mg of mine tailings that were discharged at Lead were deposited along the Whitewood Creek floodplain. Deposition of mine tailings near the mouth of Whitewood Creek was augmented by an engineered structure. About 29 per cent of the mine tailings delivered by Whitewood Creek were deposited along the Belle Fourche River floodplain. About 60 per cent of that sediment is contained in overbank deposits. Deposition along a segment of the Belle Fourche River was augmented by rapid channel migration. The proportions of contaminated sediment stored along Whitewood Creek and the Belle Fourche River are consistent with sediment storage along the floodplains of perennial streams in other, similar sized watersheds.  相似文献   

Three－dimensional　Global　Scale　Permanent－wave　Solutions　of　the　Nonlinear　Quasigeostrophic　Potential　Vorticity　Equation　and　Energy　Dispersion     

H.L. Kuo 《大气科学进展》1995,12(4):387-404

The three-dimensional nonlinear quasi-geostrophic potential vorticity equation is reduced to a linear form in the stream function in spherical coordinates for the permanent wave solutions consisting of zonal wavenumbers from 0 to n and rn vertical components with a given degree n. This equation is solved by treating the coefficient of the Coriolis parameter square in the equation as the eigenvalue both for sinusoidal and hyperbolic variations in vertical direction. It is found that these solutions can represent the observed long term flow patterns at the surface and aloft over the globe closely. In addition, the sinusoidal vertical solutions with large eigenvalue G are trapped in low latitude, and the scales of these trapped modes are longer than 10 deg. lat. even for the top layer of the ocean and hence they are much larger than that given by the equatorial β-plane solutions. Therefore such baroclinic disturb-ances in the ocean can easily interact with those in the atmosphere.Solutions of the shallow water potential vorticity equation are treated in a similar manner but with the effective depth H = RT / g taken as limited within a small range for the atmosphere.The propagation of the flow energy of the wave packet consisting of more than one degree is found to be along the great circle around the globe both for barotropic and for baroclinic flows in the atmosphere.  相似文献   

The value ofC efor the Arabian Sea during summer monsoon     

A. Suryachandra Rao  Y. Sadhuram  V. V. Gopala Krishna 《Journal of Earth System Science》1995,104(4):607-611

We estimate, from the moisture budget the bulk aerodynamic coefficient for latent heat flux (C _e) during the monsoon season over the central Arabian Sea. The average value ofC _eunder active monsoon conditions was found to be 2.25 × 10⁻³ which is nearly 60% higher than those previously used.  相似文献   

Vertical Structure in the Marine Atmospheric Boundary Layer and its Implication for the Inertial Dissipation Method     

Anna Sjöblom  Ann-Sofi Smedman 《Boundary-Layer Meteorology》2003,109(1):1-25

The structure of the marine atmospheric boundarylayer and the validity ofMonin–Obukhov similarity theory over the seahave been investigated using longterm measurements. Three levels of turbulencemeasurements (at 10 m, 18 mand 26 m) at Östergarnsholm in themiddle of the Baltic Sea have beenanalysed. The results show that turbulentparameters have a strong dependenceon the actual height due to wave influence.The wind profile and thus thenormalised wind gradient are very sensitiveto wave state. The lower part of theboundary layer can be divided into three heightlayers, a wave influenced layerclose to the surface, a transition layer andan undisturbed ordinary surfacelayer; the depth of the layers is determinedby the wave state. This heightstructure can, however, not be found for thenormalised dissipation, which is onlya function of the stability, except duringpronounced swell where the actualheight also has to be accounted for. Theresults have implications for the heightvariation of the turbulent kinetic energy(TKE) budget. Thus, the imbalancebetween production and dissipation willalso vary with height according to thevariation of wave state. This, in turn,will of course have strong implicationsfor the inertial dissipation method, inwhich a parameterisation of the TKEbudget is used.  相似文献   

关于位涡理论及其应用的几点看法   总被引：12，自引：3，他引：9  

胡伯威 《南京气象学院学报》2003,26(1):111-115

位涡理论能非常有效地解释天然现象,预测天然系统的变化,合理应用该理论的关键是对其原本思路和原理有非常透彻的理解,本文试图对此谈几点看法。  相似文献