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161.
162.
E. G. Kolomyts 《Russian Meteorology and Hydrology》2008,33(7):430-440
The gradient (ordination) analysis was used to find the tendencies and the rate of changes in discrete parameters of the cycle of forest phytomasses accompanying a growing thermoarid climatic trend. The prognostic estimates of biotic regulation of the carbon cycle by forest biogeocenoses according to the HadCM3 (version A2) climatic scenarios, describing the most powerful coming global warming, are presented. 相似文献
163.
H. C. Aslyng 《Theoretical and Applied Climatology》1960,10(3):359-375
Summary Evaporation from an area covered with short clover-grass has been determined by means of evapotranspirometers (4 m2), open (12 m2) and screened (1/3 m2) evaporimeters, and it has been estimated on the basis ofPenman's andThornthwaite's theories, too. The results of the measurements with the various instruments are compared with each other and with the results derived from the cited theories.Further, radiation heat balances have been made, including evaporation and heating of soil and atmosphere.
With 8 Figures 相似文献
Zusammenfassung Die Verdunstung über einer mit kurzem Kleegras bedeckten Fläche wurde mittels Evapotranspirometern (4 m2), offenen (12 m2) und abgeschirmten (1/3 m2) Evaporimetern gemessen und auch auf Grund vonPenmans undThornthwaites Theorien berechnet. Die Meßergebnisse der verschiedenen Instrumente werden untereinander verglichen und auch den mittels der angeführten Theorien abgeleiteten Resultaten gegenübergestellt.Weiters wurde eine Strahlungs-Wärme-Bilanz aufgestellt, die auch die Verdunstung und die Erwärmung von Boden und Atmosphäre berücksichtigt.
Résumé On a mesuré l'évaporation sur une surface recouverte de trèfle court à l'aide d'évapotranspiromètres (4 m2) et d'évaporimètres ouverts (12 m2) et protégés (1/3 m2); les résultats de mesures, furent comparés entre eux et avec la théorie dePenman etThornthwaite.Puis on a dressé un bilan radiatif tenant compte, de l'évaporation et du réchauffement du sol et de l'atmosphère.
With 8 Figures 相似文献
164.
B. E. Peskov A. A. Alekseeva A. E. Nikiforova 《Russian Meteorology and Hydrology》2008,33(10):644-650
The physical-synoptic principles of the automated method of summer precipitation forecasting introduced into operational prognostic practice in 2006 by the decree of the Central Methodical Commission of the Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet) are presented. Beside that, improved modifications of this method, which are automatically updated, are shown. Validation of those updates based on observational data collected in 2004 has shown improvement of all major criteria of forecasts efficiency. The performed improvement is based on the more detailed quantitative realization of mechanism of various showers formation (including heavy rainfalls). 相似文献
165.
M. R. E. Proctor 《Astronomische Nachrichten》1977,298(1):19-25
The kinematic α-effect dynamo problem is investigated in the case of an exterior perfect conductor. It is shown that certain approximate symmetries discovered in the numerical analysis of ROBERTS (1972) are exact for this case. As an illustration, an exact solution is given in a cylindrical geometry, where the equations can be written in terms of one variable. The implications for the earth's dynamo are discussed. 相似文献
166.
C. P. Renschen 《Astronomische Nachrichten》1975,296(6):285-287
The present paper is a test to explain the three-month oscillation of the Great Red Spot on Jupiter as a solution of the NAVIER-STOKES equation which is coupled with a nonlinear equation of oscillation. Since several parameters resp. functions are unknown it is difficult to find quantitative solutions. 相似文献
167.
E. Leimanis 《Astronomische Nachrichten》1976,297(3):141-143
The requirement that near a singular point of the equations of motion the power series expansions of the old variables in terms of the new ones start with second order terms leads to the transformation z = sin21/2w related to that of THIELE -BURRAU . Using this new transformation, a derivation of the regularized equations of motion is given. The original as well as the regularized equations of motion are of interest, for example, for calculating the initial values of the orbital elements for SCHWARZSCHILD's periodic solutions (LEIMANIS and OLUND 1972). 相似文献
168.
D. F. Dickinson G. Kojoyan C. R. Purton R. A. Sramek H. M. Tovmassian 《Astronomische Nachrichten》1976,297(6):283-286
Radio spectra of 16 Markarian galaxies are studied between 2.7 and 15.5 GHz. The Seyfert-type galaxies have power-law spectra with an average spectral index of -0.82, except for MRK 348, which is an active galaxy with a complex spectrum. The galaxies with featureless optical spectra have rather flat radio spectra, similar to BL Lac-type objects. 相似文献
169.
170.
D. E. Roberts 《Geological Journal》1983,18(1):43-52
A section of hornfelsed Skiddaw Slate adjacent to the margin of the Grainsgill Greisen is described and chemical analyses of the various rock types presented. The results confirm that hydrothermal fluids liberated K and Na from the granite to produce the greisen. This gave rise to K metasomatism of the adjacent hornfels and to retrogressive metamorphism over a radius of 200m from the intrusion. Na leached from the hornfels near the intrusion and that liberated during the formation of the greisen are probably the sources of the Na in the brines recorded in fluid inclusions within the nearby quartz-tungsten veins. 相似文献