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1.
Summary Reitan's data on precipitable water vapour over about 45 stations of the U.S.W.B. network are correlated with altitude and average station temperature values. Computations are carried out following a simple proposed model which is found to be obeyed with reasonably good approximation on average monthly and seasonal scales.Contribution of the Centro-Nucleazione Aerosoli of the National Research Council of Italy,Rome, Via Vettore 4.  相似文献   

2.
n ¶rt;a, n¶rt;mau 531 au ¶rt; u aum m u¶rt;uu n mumu ana¶rt;, ¶rt; u -m n, aauum ¶rt;um u u amuaa n¶rt;naa ma ua aama. uu nmam an¶rt;u ¶rt; u aum aam ¶rt;au cuu uP n m , n¶rt;am mn n=1, 2, 3 u 5 (m n). u uua ¶rt;a¶rt;amu uu n¶rt;mauu uum au (a. 1) u u n aumam uu nmu, m n¶rt;mam u¶rt; am uuu ¶rt; u aum (u. 1–4). annuau 2 u 5 mn nm ma am mmmu m (u. 5, 6). ama uuu u m aam amu uu uma.  相似文献   

3.
Summary A procedure of fast computation of body-wave ray synthetic seismograms in vertically inhomogeneous media is suggested. The procedure uses a special approximation of the velocitydepth distribution which guarantees continuity of the first and second derivatives of velocity and does not generate false low-velocity layers (oscillations in the velocity-depth function). The ZESY82 program package, which is based on the suggested procedure, is described. The point source with an arbitrary radiation pattern may be situated at any points of the model, the receivers are situated regularly or irregularly along any profile on the Earth's surface, containing the epicentre. Numerical examples of the synthetic record sections for a model of the Earth's crust and the uppermost mantle are given.
¶rt;aam m¶rt; m ama ummuu a mua ¶rt;¶rt; ¶rt;, u¶rt; u nua annuauu m aa, ma nuam nm mu u n u m nu¶rt; u nu¶rt;um aau um nu mu. am nua aumn na ZESY82, a a m m¶rt;. umu aamumu uu an m ¶rt;u; nuuu ¶rt; m an¶rt; ¶rt; nu, ¶rt;a num. u¶rt; nu ummuu a ¶rt; ¶rt; ¶rt;u u amuu.
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4.
Normal density earth models   总被引：1，自引：0，他引：1  
Summary Models of the Earth's density, close to thePREM model, have been derived, they reproduce the external normal gravitational field of the Earth and its dynamic flattening, and are referred to as normal density models. The Earth's surface is approximated by an ellipsoid of the order of the flattening, or of its square. Of the group of normal models sgtisfying the solution of the inverse problem, the normal density modelHME2 is recommended. The spherically symmetric density modelPREM, which was corrected in the course of solving the inverse problem, thus creating the modifiedPREM-E2 model, was used as the a priori information.
¶rt; ¶rt;u an¶rt;u nmmu uu ¶rt;uPREM (m. a. a ¶rt;u nmmu), aumau n m u¶rt;mu na¶rt;am auaumau n u. m u annuum am unu¶rt; au. uau amu a ¶rt; mam H==0.003 273 994. ma ¶rt; a ¶rt; ¶rt;m ¶rt;HME2. am anu u a ¶rt; nmmu a unaa ¶rt; a¶rt;ua umua ¶rt;PREM. ¶rt;aam ¶rt;uuau m ¶rt;u n¶rt; aauPREM-E2.
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5.
Summary A large number of the users of the geomtrical constants of the reference ellipsoid know only the IAG resolutions and not the related special publications; consequently, the numerical values of the derived geometrical constants may be interpreted differently. Some values of possible differences (max. 32 mm) are given, and it is proposed that the GRS-80 geometrical constants be defined by the values of a and f –1 with unlimited accuracy in the next IAG resolution.
¶rt;a um nam zmuuu nmu n-unu¶rt;a am m uu ¶rt;a¶rt; auauu n z¶rt;uu, a nua nuauu; nm m num a mau u au nu¶rt; zmuu nm. mam nu¶rt;m m au am (a. 32 ) u n¶rt;azam n¶rt; uu n¶rt;m muu nm GRS-80 uuau a, f –1 zau mm.
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6.
Summary This paper is an attempt towards determination of station adjustments for Shillong and Delly Observatories from considerations of a large number ofP n residuals. Station adjustments toJeffreys-Bullen travel time tables for Shillong comes to about 4 seconds and for Delhi 2 seconds respectively for 20°.  相似文献   

7.
Summary Computation of terrain corrections from a map with a square grid of mean height points
uu mnauu nna n am ¶rt;u m u¶rt; a¶rt;am mu m nm.
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8.
Summary Using the optimal shape design method, which is generally described, and von Herzen's et al. measurements of the heat flow, the shape of the lithosphere and its thermal field is computed in the vertical plane parallel to the hot spot source versus the plate velocity at a distance of about 250 km from the axis of the Hawaiian Island chain. The results are compared with the computations based on Crough's idea of thermal rejuvenation of the oceanic lithosphere above a hot spot source. If we assume that the lateral cross-section of the lithospheric bottom is described by the Gaussian curve h=h0 exp (–y2/22), we obtain h035 km and 130 km, where h is the value of lithospheric thinning and y the lateral coordinate. We thus obtain the lower limit of the lateral dimension of the Hawaiian anomaly.
u m¶rt; nmua nua amu, m u ma nuam, u ¶rt;a mn nm, ua a um u mn n mua nmu, naa mu um mum umua mu u ¶rt;a nuuum 250 m uuuaa aunaa. mam a uuu, au a u¶rt;u aa (Crough), aauu mn mu au um a¶rt; umu mu. u n¶rt;num, m ama nn u umu ¶rt;a nuam u aa h=h0 exp (–y2/22), m num h0 35 u 130 ,¶rt; h—umu mu u —amaa ¶rt;uama. ¶rt;am, =130 m u n¶rt; ama aaaa aauu.
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9.
Summary The regular astronomical determinations of the geographic latitude and UT from Ondejov PZT observations were used to estimate the fluctuations with a frequency of 1.00217 of the sidereal day, corresponding to the theoretical value of the frequency of the nearly diurnal free wobble of the pole. The combined polar wobble and nutation as reflected in astronomical observations was analysed, and a method of estimating the amplitudes of the periodic components, based on observing changes of latitude and time during the separate observation nights, is proposed. The numerical solution indicates that fluctuations which can be considered a manifestation of retrograde free nutation with an amplitude of approximately 0.02, are present in the PZT observations.
uuau um u u u ¶rt; una ¶rt; u au amm 1,002 17 ¶rt; m, mmm ¶rt; um ¶rt;uu na, ¶rt;am aau uu ¶rt;u mauu u ¶rt;uu na amuu a¶rt;u. ¶rt;aam m¶rt; ¶rt; u nu¶rt;uu ua, u¶rt;u u uu um u u m¶rt; a¶rt;u. u mam u¶rt;um a ¶rt; um mauu anau nmu ¶rt;uu a mu anum¶rt; 0,02.
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10.
Summary In a number of VLF experiments with low-orbiting Intercosmos satellites, high-intensity, discrete VLF emissions at frequencies above the local LHR were observed predominantly between L=2.3 and 4.0. The frequency of their intensity maximum varies continuously with geomagnetic latitude, and approximately parallels the value of a quarter of the equatorial electron gyrofrequency. An attempt is made to interprete these emissions in terms of quasi-electrostatic whistler-mode waves, generated in the near-equatorial region and propagating downward in the quasi-resonance mode. The generating mechanism is supposed to be the kinetic instability connected with the loss-cone and temperature anisotropy of the distribution function of energetic electrons. Some features of the discrete plasmaspheric emissions are discussed on the basis of theoretical considerations.
¶rt; num a umu nmua m a¶rt;au umu ¶rt;um -uu a amma, a amm , num ¶rt; L=2,3 u L=4. amma aua umumu mu uu um uuaum um u nuuum aa mmu amuauamm m. ¶rt;numa nnma umnmuam mu uu mua aummamuu um , ¶rt;a nuamua amu u anmau u au-a u. ¶rt;naam, m mu uu ¶rt;am mam umu mumu an¶rt;u u m, aumnu mnam u nm u uu an¶rt;u. n mmu aau ¶rt;am m mu ¶rt;umm na uu.
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11.
nuam aau ¶rt; amu a um ¶rt; ¶rt;a uauu. ¶rt; ¶rt;a, ¶rt;mu auumu m mnam u nu mum ¶rt;a, umam m ¶rt;u z aa n¶rt; uuu, a aau. u¶rt; auum ¶rt;au z naa m mauu ¶rt; amu, naam, m ¶rt;au ¶rt;z naa zauuam u amu ¶rt;.
Summary A formation of ice particles on artificial deposition INis described. INacting in dependence on the temperature and supersaturation over the ice are considered in the 1 D SSconvection cloud model with detailed microphysics including freezing. The limiting influence of the water vapour pressure upon the concentration of active INis shown resulting from the dependence of water vapour pressure on the ice particle concentration.
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12.
Summary It is recommended that the data from measurements with supraconducting gravity meters be also analysed with regard to verifying the gravitation absorption hypothesis. Based on theoretical data from a3-year period, the spectrum of the assumed effect of shielding the gravitational influence of the Sun by the Earth's body on the value of the acceleration of gravity has been calculated for the tidal station Brussels (Figs 2a–e).
¶rt;aam aauuam ¶rt;a uu n¶rt;uaumau ma mu u nuunm n¶rt;auaumauu. a mmuu ¶rt;a a mmu nu¶rt; u nm n¶rt;naa ma auauaumau ¶rt;mu a m a uu u u mmu ¶rt; nuu mauu (u. 2a–).
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13.
Summary The atmospheric transmissivity in the water vapour absorption band (6–6.5 ) is evaluated using the recent Tiros III data and based onGoody's statistical model.Work completed while on leave from the Department of Meteorology, University of California, Los Angeles.  相似文献   

14.
Seismic activity that preceded, accompanied, and followed the 17–23 March 1981 Etnean eruption has been statistically analyzed.On the grounds of both time evolution of seismicity and catalogue completeness, three time intervals have been defined (12 February–2 March, 12–17 March, 19–31 March) and for each of these periods both the b coefficient of theGutenberg-Richter's (1956) relationship and the E parameter of the cluster size (Shlien andToksoz, 1970) have been calculated.No significant variations were observed between the first and third periods, while lower values of bothb andE coefficients were found in the second one. These findings might indicate that changes in the seismicity features occur just before the eruption start.Small but fast variations in the stress field acting on the volcano might originate this type of seismic activity, while the importance of the tectonic control on volcanic phenomena seems to be confirmed.  相似文献   

15.
The effect of atmospheric precipitation on the hydrogeochemical regime of subsoil water is studied in the case of Usad'e watershed in Novgorod oblast. Thermodynamic and mathematical models are used to generalize the results of long-term hydrogeological studies and predict the propagation of acidification front in groundwater flow.  相似文献   

16.
Summary The Banach theorem is applied to the Lagrange planetary equation for the semimajor axis of a geostationary satellite orbit to estimate the stability of near-geostationary satellite orbits. To achieve a graveyard (disposal) orbit, which will not interfere (=cross) the initial geostationary orbit, the geostationary semi-major axis ag have to be increased at least by 50 km. Numerical results for a variety of graveyard orbits show that the increase of ag by about 100 km will yield sufficiently stable orbits (accounting for the Earth's gravitational perturbations only) during the next 150 years.Dedicated to the 75th Birthday of Professor Academician Tibor Kolbenheyer  相似文献   

17.
Ionosphere-magnetosphere disturbances at high latitudes, e.g. magnetic substorms, are accompanied by energetic particle precipitation and strong variations of the ionospheric electric fields and currents. These might reasonably be expected to modify the local atmospheric electric circuit. We have analysed air-earth vertical currents (AECs) measured by a long wire antenna at Esrange, northern Sweden during 35 geomagnetic substorms. Using superposed epoch analysis we compare the air-earth current variations during the 3 h before and after the time of the magnetic X-component minimum with those for corresponding local times on 35 days without substorms. After elimination of the average daily variation we can conclude that the effect of substorms on AEC is small but distinguishable. It is speculated that the AEC increases observed during about 2 h prior to the geomagnetic X-component minimum, are due to enhancement of the ionospheric electric field. During the subsequent 2 h of the substorm recovery phase, the difference between substorm and quiet atmospheric currents decreases. The amplitude of this substorm variation of AEC is estimated to be less than 50% of the amplitude of the diurnal variation in AEC during the same time interval. The statistical significance of this result was confirmed using the Van der Waerden X-test. This method was further used to show that the average air-earth current and its fluctuations increase during late expansion and early recovery phases of substorms.  相似文献   

18.
Summary The primary scattering of atmospheric haze is computed by modification of an approximative method evolved byde Bary, basing on skylight measurements carried out on the Musalla, a mountain of 3000 m height in Bulgaria, at various altitudes of the sun and in different horizontal circles at a wavelength of 450 nm. This measured total radiation is reduced by the radiation induced by the scattering at molecules as well as by secondary or multiple scattering at turbidity aerosol. The single scattering of the atmospheric haze thus computed is discussed for various assumed Linke turbidity factors.The concluding deductions relate to a comparison of haze scattering functions with theoretical scattering functions, the results attained agreeing closely with superimposed logarithmic Gaussian distributions and only partly with the scattering functions computed byBullrich. These deductions prove optically the increase of larger particles (r 00.64 m) during forenoon. The analysis of the scattering functions conductes to a shortage of particles withr 0=0.2 m in agreement with other investigations.
Zusammenfassung In Abwandlung einer vonde Bary angegebenen Approximationsmethode wird die Primärstreuung des atmosphärischen Dunstes berechnet. Zugrundegelegt werden Himmelsllichtmessungen, die auf dem etwa 3000 m hohen Mus Alla in Bulgarien bei verschiedenen Sonnenhöhen und in verschiedenen Horizontalkreisen bei einer Wellenlänge von 450 nm durchgeführt wurden. Von dieser gemessenen Gesamtstrahlung werden die Anteile substrahiert, die durch Streuung an Molekülen sowie durch zwei-oder mehrfache Streuung an Trübungsaerosol hervorgerufen werden. Die so berechnete Einfachstreuung des atmosphärischen Dunstes wird für verschiednee angenommene Linke'sche Trübungsfaktoren diskutiert.Abschließend werden die Dunststreufunktionen mit theoretischen Streufunktionen verglichen, wobei eine gute Übereinstimmung mit überlagerten logarithmischen Gauß-Verteilungen und nur teilweise mit vonBullrich berechneten Streufunktionen erzielt wurde. Es kann dabei optisch die Zunahme großer Teilchen (r 00,64 m) im Laufe des Vormittags gezeigt werden. Die Analyse der Streufunktionen führt zu einem Fehlen von Teilchen mitr 0=0,2 m in Übereinstimmung mit anderen Untersuchungen.
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19.
Summary The problem of the propagation of finite Love Waves in a heterogeneous elastic half space lying over a homogeneous elastic half space, using the quasilinear stress-strain relation due toS. Ferhst [4] is considered in detail. The variations of the parameter in the layer assumed to be of the form 1= 0e z, 0e z where is a constant andz is distance measured from the surface into the layer.  相似文献   

20.
Summary The frequency equation of Rayleigh waves propagating over the free surface of an isotropic, perfectly elastic, heterogeneous semi-infinite medium with material properties varying as = 0 e az , = 0 e az , = 0 e az (a>0) has been obtained. Solution of the frequency equation in closed form is obtained in two cases (i) =0, (ii) =, and the Rayleigh wave dispersion curves for phase and group velocities drawn. In both the cases the medium yields single Rayleigh modes which cannot propagate below certain cut-off frequencies. It is found that in case (i), <c<c 0 and 0.87500 <c g <c 0, and in case (ii), 1.03082 <c<c 1 and 0.90850 <c g <c 1, wherec andc g denote phase nad group velocities respectively, is the constant shear wave velocity of the mediumc 0 andc 1 are the corresponding Rayleigh wave velocities of the homogeneous medium of the same Poisson's ratio. The motion of the surface particles is found to be retrograde elliptical as in the homogeneous case, but the ratic of the major and minor axes now becomes frequency dependent and is plotted against frequency. In both the cases (i) and (ii), the ratio starts at a lower value at the cut-off frequency and approaches the corresponding value of the homogeneous medium at high frequencies.  相似文献   

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