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981.
M. A. Anastassiades L. N. Carapiperis N. K. Kariambas P. G. Paraskevopoulos 《Pure and Applied Geophysics》1962,52(1):143-152
Summary In this study the different forms of the electromagnetic field strength recordings at the Thera-Crete microwave line of link are examined, in comparison with the corresponding weather situations prevailing over that area. According to the amplitude of fluctuations, the different forms of recordings have been classified in three basic typesA, B, C and the annual frequency of the appearance of these types has been observed. Finally, the influence of weather situations on radio wave propagation was examined and it has been found that in most cases a close relationship exists between weather situations and the different fading forms of the electromagnetic field so that a prediction of the fading form be possible by means of the weather forecast.This study was sponsored by a research grant from NATO's Scientific Committee. 相似文献
982.
983.
J. Drimmel 《Meteorology and Atmospheric Physics》1964,14(2):213-217
Zusammenfassung Die bisher ungeklärte Winter-Anomalie der D-Schicht sowie die explosionsartigen Erwärmungen der Hochstratosphäre im Winter können durch Staubpartikel interplanetaren Ursprungs (Meteorströme) hervorgerufen werden. Eine Anlagerung von Elektronen an die Staubteilchen in der Exosphäre bewirkt das Einfangen der kleinsten Partikel durch das erdmagnetische Feld und verhindert so ihr Verglühen in der Ionosphäre. Durch Sedimentation und turbulente Diffusion gelangt der Meteorstaub bis in die Ozonosphäre, wo er oxydiert wird und so eine plötzliche Wärmeentwicklung zur Folge hat. Die angelagerten Elektronen exosphärischen Ursprungs können bei zeitgerechter Photoablösung elektromagnetische Wellen dämpfen und so die Winter-Anomalie der D-Schicht hervorrufen.
Summary The winter-anomaly of the ionospheric D-region for which no sufficient explanation existed up to now, as well as the explosive warming of the high stratosphere in wintertime are possibly caused by dust particles of inter-planetary origin (meteoric showers). The attachment of electrons on the dust particles in the exosphere causes the magnetic field of the earth to catch the smallest particles and so they do not evaporate in the ionosphere. By sedimentation and turbulent diffusion the meteoric dust reaches the ozonosphere where it is oxidized, which is followed by a sudden development of heat. After photo-detachment in due time the formerly attached electrons of exospheric origin are able to damp electro-magnetic waves and by this they cause the winter-anomaly of the D-region.
Résumé L'anomalie de la couche D — inexplicable jusqu'ici — ainsi que les hausses prodigieusement rapides de la température de la haute stratosphère, deux phénomènes particuliers de l'hiver, peuvent être provoquées par des particules de poussière d'origine interplanétaire (courants de météorites). Des électrons adhérant, dans l'exosphère, aux grains de poussière permettent l'entraînement des plus petites particules par le champ magnétique terrestre et empèchent ainsi leur désintégration dans l'ionosphère. Par sédimentation et diffusion turbulente, la poussière cosmique parvient ensuite jusque dans l'ozonosphère où elle est oxydée. Il en résulte alors un dégagement subit de chaleur. Les électrons d'origine exosphérique adhérant à la poussière cosmique peuvent atténuer, s'ils s'en détachent en temps opportun sous l'effet du rayonnement solaire, les ondes électromagnétiques et provoquer ainsi l'anomalie d'hiver de la couche D.相似文献
984.
D. J. Schove 《Pure and Applied Geophysics》1963,55(1):249-261
Summary The geometry of the principal Upper High (near the Indian Occean) in the 300–100 mb layer appears to account for the Southern Oscillation (S.O.), and models of its behaviour are presented. Significant features of these models include the equatorial points of upper convergence (C) and divergence (D), a pressure discontinuity (CNDS) forming «arcs» and an «enclosure» around the high, and, lastly, encircling «crescents» both outside and inside the enclosure. The geography of the seasonal sucession can thus—in a qualitative manner—be interpreted in the light of known wind and contour patterns near the tropopause. With a few general principles, the established empirical rules of long-range forecasting then follow by deduction. The models and the terminology are useful likewise in the interpretation of solar-terrestrial relations and of climatic fluctuations. 相似文献
985.
Victor P. Starr 《Pure and Applied Geophysics》1963,56(1):163-173
Summary Equations for the motions in a galaxy which is controlled by gravitational forces and inertial effects are formulated. It is found that for the motions relative to the rotating system formulae analogous, and of similar form, to the geostrophic wind equations may be written. From these formulae and from the distribution of the relative gravitational potential in the disc of the galaxy, it is found that a spiral tendency in the mass distribution carries the implication of an inward flux of angular momentum by advective processes. This is to be compared with an outward flux through gravitational torques obtained in previous studies in which the writer participated. 相似文献
986.
Victor P. Starr 《Pure and Applied Geophysics》1963,56(1):159-162
Summary A gradually cumulative error due to the use of the hydrostatic approximation is examined through consideration of a simple mathematical model taken from the classical theory of gravity waves. Two cases are chosen which differ solely in the circumstance that in one the hydrostatic assumption is made while in the other it is not. A large divergence of the results present in the later stages is then to be referred to the neglect of terms contained in the exact equation of motion for the vertical direction in one of the solutions. The inference is drawn that comparable phenomena might arise in the integration of the atmospheric equations over long time periods. 相似文献
987.
Phase relationships on the vapor-saturated liquidus surfacein the system CaO-MgO-CO2-H2O have been deduced from data inthe systems CaO CO2-H2O, CaO-MgO-CO2, and MgO-CO2-H2O, and frompreliminary experiments in the quaternary system. These areillustrated in composition tetrahedra, and in isobaric sectionsthrough the petrogenetic model. The univariant PT curve forthe beginning of melting lies between 625? C and 600? C in thepressure range 10 bars to 4 kilobars, in the presence of a vaporphase rich in H2O. The curve is divided into three sectionsby two invariant points, each section having a different primarymagnesian phase involved in the melting reaction. Periclaseoccurs on the low-pressure section (less than about 1 kilobar),and with increasing pressure first brucite and then dolomitebecome stable on the liquidus. The pressure of the second invariantpoint, above which dolomite is stable on the liquidus, is notknown. The effect of FeO as an additional component is considered.Processes of crystallization resulting from changes in temperature,in pressure, and in the composition of the vapor phase are discussed.These processes are applied to the crystallization and differentiationof carbonatite magmas, and the reverse processes involving fusionare applied to the metamorphism of dolomites. Crystallizationdifferentiation of a carbonatite magma could produce the sequenceof intrusion observed at some carbonatite complexes: calcitics?vite, followed by ankeritic s?vite, and finally sideriticcarbonatite. Partial melting may occur during the thermal metamorphismof dolomites, but melting is unlikely during regional metamorphism. 相似文献
988.
F. Steinhauser W. Mörikofer J. Drimmel Peter Steinhauser 《Meteorology and Atmospheric Physics》1965,15(2):251-264
Ohne Zusammenfassung 相似文献
989.
J. A. Eden 《The Photogrammetric Record》1966,5(27):150-169
Some of the advantages and disadvantages of super-wide angle photography are discussed. Special reference is made to photography of an area in Bechuanaland, when airborne profile recorder and horizon camera were used in conjunction with aerial photography. Data from these ancillary aids were used in the subsequent adjustment procedure. The paper concludes with an account of analytical bridging using super-wide angle photography and a monocomparator. 相似文献
990.