Local Scales of Turbulence in the Stable Boundary Layer   总被引：1，自引：1，他引：0  

Zbigniew Sorbjan 《Boundary-Layer Meteorology》2008,127(2):261-271

Local, gradient-based scales, which contain the vertical velocity and temperature variances, as well as the potential temperature gradient, but do not include fluxes, are tested using data collected during the CASES-99 experiment. The observations show that the scaling based on the temperature variance produces relatively smaller scatter of empirical points. The resulting dimensionless statistical moments approach constant values for sufficiently large values of the Richardson number Ri. This allows one to derive predictions for the Monin–Obukhov similarity functions φ _m and φ _h , the Prandtl number Pr and the flux Richardson number Rf in weak turbulence regime.  相似文献   

An Evaluation of the Flux–Gradient Relationship in the Stable Boundary Layer     

Zbigniew Sorbjan  Andrey A. Grachev 《Boundary-Layer Meteorology》2010,135(3):385-405

Data collected during the SHEBA and CASES-99 field programs are employed to examine the flux–gradient relationship for wind speed and temperature in the stably stratified boundary layer. The gradient-based and flux-based similarity functions are assessed in terms of the Richardson number Ri and the stability parameter z/Λ_*, z being height and Λ_* the local Obukhov length. The resulting functions are expressed in an analytical form, which is essentially unaffected by self-correlation, when thermal stratification is strong. Turbulence within the stably stratified boundary layer is classified into four regimes: “nearly-neutral” (0 < z/Λ_* < 0.02), “weakly-stable” (0.02 < z/Λ_* < 0.6), “very-stable” (0.6 < z/Λ_* < 50), and “extremely-stable” (z/Λ_* > 50). The flux-based similarity functions for gradients are constant in “nearly-neutral” conditions. In the “very-stable” regime, the dimensionless gradients are exponential, and proportional to (z/Λ_*)^3/5. The existence of scaling laws in “extremely-stable” conditions is doubtful. The Prandtl number Pr decreases from 0.9 in nearly-neutral conditions and to about 0.7 in the very-stable regime. The necessary condition for the presence of steady-state turbulence is Ri < 0.7.  相似文献   

A statistical model for spatial inventory data: a case study of N2O emissions in municipalities of southern Norway   总被引：1，自引：0，他引：1  

Joanna Horabik  Zbigniew Nahorski 《Climatic change》2010,103(1-2):263-276

In this paper we apply a linear regression with spatial random effect to model geographically distributed emission inventory data. The study presented is on N₂O emission assessments for municipalities of southern Norway and on activities related to emissions (proxy data). Taking advantage of the spatial dimension of the emission process, the method proposed is intended to improve inventory extension beyond its earlier coverage. For this, the proxy data are used. The conditional autoregressive model is used to account for spatial correlation between municipalities. Parameter estimation is based on the maximum likelihood method and the optimal predictor is developed. The results indicate that inclusion of a spatial dependence component lead to improvement in both representation of the observed data set and prediction.  相似文献   

一种改进的SAR干涉图综合滤波算法研究     

宋瑞  刘广  PERSKI Zbigniew  郭华东 《国土资源遥感》2012,(1):28-35

SAR干涉图作为相位信息的载体,其质量直接影响对研究区域形变状况的进一步分析,采取有效的滤波算法能抑制干涉图相位噪声,提高干涉测量精度。在获得的干涉相位图中,由于矿区开采而造成的地表沉降会体现出近环状相位条纹的特征。针对这一特点,对传统的基于梯度的滤波算法做出了改进,并结合Goldstein频域滤波和改进的梯度自适应滤波,提出了一种适用于矿区沉降形成的SAR干涉相位模式滤波方法。选取河北峰峰煤矿的PALSAR干涉相位图作为实验数据,对该滤波方法做出了详细的性能评价和对比。结果表明,采用本文提出的综合滤波方法在显著降低实验区SAR干涉图相位噪声的同时,也很好地保持了相位分辨率,使由于矿区沉降而造成的形变相位环的边缘形态更加清晰。  相似文献   

Solar Soft/Hard X-ray Photometer–Imager Aboard the Interball–Tail Probe     

Sylwester  J.  Fárník  F.  Likin  O.  Kordylewski  Z.  Siarkowski  M.  Nowak  S.  Płocieniak  S.  Trzebiński  W. 《Solar physics》2000,197(2):337-360

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Observations of Solar X-ray Spectra by the DIOGENESS and RESIK Spectrometers Onboard the <Emphasis Type="Italic">CORONAS-F</Emphasis> Satellite     

J. Sylwester  B. Sylwester  Z. Kordylewski  K. J. H. Phillips  V. D. Kuznetsov  S. I. Boldyrev 《Solar System Research》2005,39(6):479-488

The first scientific results of the analysis of the X-ray spectra of flares and active regions in the solar corona obtained by Polish-led spectrometers RESIK and DIOGENESS onboard the CORONAS-F satellite are presented. The instruments were designed and made in the Solar Physics Division of the Space Research Center of the Polish Academy of Sciences (SRC PAS, Wroclaw, Poland). The Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation (IZMIRAN, Russia) and the Astronomical Institute of the Czech Academy of Sciences also participated in designing the DIOGENESS spectrometer, while IZMIRAN (Russia), Mullard Space Science Laboratory (MSSL, Great Britain), Rutherford Appleton Laboratory (RAL, Great Britain), and Naval Research Laboratory (NRL, United States) contributed to the development of the RESIK spectrometer. In the paper, we give spectra obtained in a number of previously unstudied spectral ranges and a preliminary identification of new spectral lines. The results for the shifts of the X-ray spectral lines observed with the use of a so-called dopplerometer configuration are also presented. Methods for determining the abundances of the rare elements in the solar corona, including chlorine, potassium, and argon, are described.  相似文献   

Structure of the stably-stratified boundary layer during the SESAME-1979 experiment     

Zbigniew Sorbjan 《Boundary-Layer Meteorology》1988,44(3):255-266

Airplane measurements in the stable boundary layer during the SESAME-1979 experiment (southcentral Oklahoma, U.S.A.) are examined in terms of the local similarity theory. The obtained results are compared with data from the Minnesota (1973) experiment and with data collected previously on towers in Cabauw (Netherlands) and Boulder (Colorado, U.S.A.). The comparison indicates that the SESAME data are strongly influenced by the terrain features of the experimental site.On leave from: Institute of Environmental Engineering, Warsaw Technical University, 00653 Warsaw, Poland.  相似文献   

Book review     

David Gubbins  Emile A. Okal  Roberto Scarpa  R. E. Anderson  Leszek Czechowski  Rodney W. Page  Bernhard Spörli  Magdalena Kądziałko-Hofmokl  J. A. Majorowicz  Gregory Houseman  Donald L. Turcotte  David F. McTigue  Teng-fong Wong  David Lockner  David V. Wiltschko  David M. Fountain  G. P. Glasby  R. J. Angel  S. J. Gibowicz  Jonathan Franzen  Kacper R. Rybicki  Brian Farrell  Anil Suri  Zbigniew W. Kundzewicz  Witold G. Strupczewski 《Pure and Applied Geophysics》1988,127(4):695-752

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Petroleum exploration models—Estimation and applications     

Zbigniew ?ucki  Zbigniew Szkutnik 《Mathematical Geology》1989,21(5):495-512

Three statistical models of oil and gas exploration prevail in the literature: field size distribution, exploration function, and effectiveness of exploration models. They may have many functional forms and may be used for prediction and planning results of future exploration activity. A review of American and Soviet literature of exploration models is presented with special emphasis on functions suitable for countries which, like Poland, are not rich in oil and gas. Two new procedures are proposed: a method for assessing field size distribution and a method for simultaneous interval estimation of parameters of the exploration function. The methods complement existing ones as they are suited to areas that are not rich in hydrocarbons. Examples of application to exploration of two Polish petroliferous basins are given.  相似文献   

Structural integrity of cracks in the head of Washington on Mount Rushmore     

Zbigniew Hladysz 《Geotechnical and Geological Engineering》1989,7(4):315-322

Summary Preliminary studies of the stability of Mt Rushmore shows a tendency for permanent crack deformation resulting from seasonal opening and closing of cracks in the structure.  相似文献