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Yu. N. Koren’kov F. S. Bessarab N. A. Koren’kova V. S. Leshchenko 《Geomagnetism and Aeronomy》2018,58(3):420-429
The study presents the results of the analysis of the F2-layer critical frequency variations obtained for the winter periods of 2008–2010, during which sudden stratospheric warmings were observed. The data were obtained at Kaliningrad ionospheric station (54.6° N, 20° E) with the Parus digital ionosonde in standard sounding mode. The mean daily foF2 values were used in the analysis. The results of spectral analysis based on continuous wavelet transform showed that, during all of the warmings that occurred in 2008–2010, the foF2 time variations demonstrated the presence of wave processes with periods of approximately 5?6 days, as well as more extended processes with periods of ~10?13 and 23?30 days. These periods coincide with the characteristic periods of planetary waves observed in the mesosphere during sudden stratospheric warmings, while the 13- and 30-day periods can be conditioned by the influence of the Sun. 相似文献
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Analysis of vertical sounding data obtained on the network of domestic stations equipped with Parus-A ionosondes has shown that anomalous reflections from the ionosphere previously detected in Moscow are observed throughout the whole mid-latitude region. It is shown that the longitudinal effect impacts the probability of the appearance of anomalous reflections. Their spatiotemporal scales are determined. The horizontal dimensions of the anomalies, as a rule, range from several tens to several hundred, possibly a thousand, kilometers. The region of altitudes at which anomalous reflections are observed extends from the E region to F2 layer. The frequency range in which they are most often recorded is from 2 to 14 MHz. The time of their existence ranges from a fraction of minutes to many hours. 相似文献
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The existence of anomalous ionospheric reflections was shown on the basis of vertical soundings at the Moskow station. They are observed at heights of 100–200 km. These anomalous reflections are not related to the main Ne(h) ionospheric profile. Morphological characteristics of such reflections are presented: the daily, seasonal, and cyclic dependences of their appearance. 相似文献
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Izvestiya, Atmospheric and Oceanic Physics - In this paper we show that the concept of cooling and settling of the middle and upper atmosphere formulated in 1999 finds new experimental... 相似文献
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G. V. Givishvili L. N. Leshchenko V. V. Alpatov S. A. Grigor’eva S. V. Zhuravlev V. D. Kuznetsov O. A. Kusonskii V. B. Lapshin M. V. Rybakov 《Solar System Research》2013,47(4):280-287
The data, obtained for the first time, permit the conclusion to be drawn, with a high degree of probability, that large meteors similar to the Chelyabinsk meteor, while entering the Earth’s atmosphere, are able to cause perturbations within the whole ionospheric stratum, rather than only at the sporadic Es layer altitudes, as previously thought. 相似文献
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L. P. Korsunova Yu. M. Mikhailov V. V. Khegai L. N. Leshchenko S. E. Smirnov V. V. Bogdanov 《Geomagnetism and Aeronomy》2010,50(7):920-926
We consider data obtained when the parameters of the ionospheric Es and F2 layers and the vertical gradient of the electric potential in the surface atmosphere were simultaneously measured
during the preparatory period of crustal earthquakes with M = 5.0–6.2 in the Kamchatka region. The appearance of anomalously high Es, accompanied by an increase in frequency parameters of the sporadic layer and the regular F2 layer, was detected on days
when possible earthquake precursors, as determined earlier, occurred in atmospheric electric fields. The presumed earthquake
precursors in the ionosphere are divided into two groups with different earthquake lead times ranging from several hours to
two weeks. Empirical dependences are presented that connect the lead time of an earthquake (from the moment of the appropriate
anomaly’s occurrence in the ionosphere or in the atmospheric electric field to the moment of the shock) and the epicentral
distance to the observation point with the earthquake magnitude. These dependences are different for the two groups of presumed
earthquake precursors, but they are close inside each group of possible precursors selected on the basis of quasistatic electric
field measurements and revealed in ionospheric parameter variations. 相似文献
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Geomagnetism and Aeronomy - The article analyzes the errors in estimating the parameters of the main ionospheric maximum, plasma frequency foF2 and its height hmF2, by automated systems for... 相似文献
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V. E. Chertoprud L. N. Leshchenko G. V. Givishvili E. E. Goncharova G. S. Ivanov-Kholodny 《Geomagnetism and Aeronomy》2009,49(4):503-509
The 40-year period of observations of short-term variations (with characteristic times of up to 1–2 days) in the critical frequency of the ionospheric F2 layer (foF2) is analyzed. The continuous (with a step of 1 h) series of fluctuations (F) of the foF2 critical frequency (with eliminated daily variations) has been calculated using the hourly variations in foF2 at Moscow stations. The fractal dimension (FRH) of the fluctuations, characterizing short-term variations in foF2, has been determined and analyzed on a 30-day interval, using the Higuchi method. It has been established that FRH estimates substantially change in time. The 11-year cycle, which is in antiphase with the solar cycle, and the total annual and semiannual variations, similar to the variations observed in the normalized critical frequency of the E region and in the electron density of the D region, are clearly defined in these changes. Thus, the parameters of fast variations in the ionospheric F2 layer are affected by the phase of the 11-year solar cycle and by the position of the Earth in the orbit or seasonal variations in the atmosphere. 相似文献
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