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The results of the determination of centimeter ( = 5 cm) radio waves absorption in the radio occultation experiments, carried out using the Venera-15and Venera-16spacecraft, are presented. The altitude distribution of the absorber substance is analyzed. The absorbing layer is shown to exist at altitudes of 64 to 58 km in the near-polar regions of the planet. At middle latitudes such an absorbing layer was not found. In the altitude range from 56 to 46 km the radio wave absorption by the sulfuric acid (H2SO4) vapor is observed. The content of the sulfuric acid vapor is shown to increase with decreasing altitude: in the mid-latitude region at altitudes of 56.7 and 53 km it equals 5 and 20 ppm, respectively, and at polar latitudes the same content of H2SO4vapor is observed at altitudes of 51.2 and 47 km, respectively. A comparison of these results with the data of radio wave absorption in the = 13 cm band, obtained in the Pioneer Venus Orbiterradio occultation experiments, leads to the conclusion that the obtained values of the sulfuric acid vapor content well agree in the regions of overlap of the data. 相似文献
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Vladimir N. Gubenko A.G. Pavelyev I.A. Kirillovich Y.-A. Liou 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(7):1702-1716
We have used the radio occultation (RO) satellite data CHAMP/GPS (Challenging Minisatellite Payload/Global Positioning System) for studying the ionosphere of the Earth. A method for deriving the parameters of ionospheric structures is based upon an analysis of the RO signal variations in the phase path and intensity. This method allows one to estimate the spatial displacement of a plasma layer with respect to the ray perigee, and to determine the layer inclination and height correction values. In this paper, we focus on the case study of inclined sporadic E (Es) layers in the high-latitude ionosphere based on available CHAMP RO data. Assuming that the internal gravity waves (IGWs) with the phase-fronts parallel to the ionization layer surfaces are responsible for the tilt angles of sporadic plasma layers, we have developed a new technique for determining the parameters of IGWs linked with the inclined Es structures. A small-scale internal wave may be modulating initially horizontal Es layer in height and causing a direction of the plasma density gradient to be rotated and aligned with that of the wave propagation vector k. The results of determination of the intrinsic wave frequency and period, vertical and horizontal wavelengths, intrinsic vertical and horizontal phase speeds, and other characteristics of IGWs under study are presented and discussed. 相似文献
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A method for determination of internal gravity wave (IGW) parameters from a single vertical temperature or density profile
measurement in the Earth’s atmosphere has been developed. This method may be used for the analysis of profiles measured by
any techniques in which the accuracy is enough to measure small (∼1%) amplitudes of the temperature or density fluctuations
in the atmosphere. The criterion for the IGW identification has been formulated and argued. In the case when this criterion
is satisfied then analyzed fluctuations can be considered as wave-induced. The method is based upon the analysis of relative
amplitude thresholds of the temperature or density wave field and upon linear IGW saturation theory in which amplitude thresholds
are restricted by dynamical instability processes in the atmosphere. In order to approbate the method we have used data of
simultaneous radiosonde measurements of the temperature and wind velocity in the Earth’s stratosphere where the saturated
IGW propagation has been detected. It is shown that the application of the method to radio occultation temperature data gives
the possibility to identify IGWs in the Earth’s lower stratosphere and to determine values of key wave parameters. 相似文献
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Development of Satellite Methods for Radio Holographic Surveys of the Earth's Surface and Atmosphere
Zakharov A. I. Pavelyev A. G. Sinilo V. P. Gubenko V. N. Kucherjavenkov I. A. Kucherjavenkov A. I. 《Cosmic Research》2003,41(6):574-578
The methods of studying the Earth's surface and troposphere with the help of coherent radio waves radiated by satellites are considered. Some examples of measurements of the local relief of the Earth's surface by the method of radar interferometer are presented, as well as refraction profiles of the troposphere obtained by the radio holographic method. The described methods are promising for investigations of the local relief of the Earth's surface and its changes, for studying the characteristics of sea heaving, and for monitoring atmospheric processes. 相似文献
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The results of the cross-correlation analysis of the amplitude fluctuations of radio waves of the = 32 cm band in seven sessions of radio occultation measurements of the northern polar atmosphere of the planet are presented. The existence of the cross-correlation of fluctuations (b
0.6) is established in the altitude realizations in the interval 61.5–65.0 km for two different sessions of radio occultation. Inner layering is revealed in the upper layer of the clouds of the planet at altitudes of 61.5–65.0 km, which is specified by an enhanced turbulence of the atmosphere. It is found that the lifetime of the small-scale layered irregularities is no less than 2 days and that their horizontal extension in the meridional direction can exceed 130 km. A possible cause of the emergence of the layered structures inside the upper layer of the polar clouds of Venus is discussed. 相似文献
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