排序方式： 共有32条查询结果，搜索用时 937 毫秒
1.
Analysis of the connection of ice cover parameters of the non-Arctic seas in the European part of Russia with global atmospheric processes 总被引：1，自引：0，他引：1
Criteria of winter severity for three non-Arctic European seas are determined from long time series of observations. Periods and dates of indices of macrocirculation epochs are estimated. Results of analysis of the connection of macrocirculation processes (E, W, and C forms of atmospheric circulation) with winter severity and with the ice concentration and thickness of the White Sea, the Gulf of Finland, and the Sea of Azov are presented. Some aspects of the ice cover evolution in the non-Arctic European seas are identified for various latitudinal zones from analysis of changes in global atmospheric processes over a large territory. 相似文献
2.
T. G. Kogai I. V. Golovchanskaya I. A. Kornilov T. A. Kornilova Y. V. Fedorenko 《Geomagnetism and Aeronomy》2016,56(1):8-18
Using data from THEMIS spacecraft we investigated transverse to the magnetic field mutually perpendicular electric and magnetic components of ballooning type perturbations with periods 60–240 s, which are observed in the magnetospheric plasma sheet during the period preceding substorm onset. With applying Hilbert transform, we analyzed the phase relations between them. It is shown that the perturbations are dominated by radial electric and azimuthal magnetic (that is, toroidal) components which are usually in phase or out-of-phase. Along with them, approximately 2.5 times less intense azimuthal electric and radial magnetic components are present, which are more often phase-shifted by π/2. It is concluded that the observed perturbations are not a simple consequence of the development of plasma sheet ballooning instability, leading to the growth of strongly elongated along the magnetotail ballooning structures. It is pointed out that this conclusion is confirmed by simultaneous ground-based observations of magnetically conjugate auroral structures. 相似文献
3.
4.
A. K. Fedorenko 《Geomagnetism and Aeronomy》2010,50(1):107-118
Wave disturbances of the Neutral Atmosphere above the polar caps are studied based on the Dynamic Explorer 2 satellite measurements.
The characteristic spatial scales of these disturbances are 500— 600 km. Based on an analysis of the synchronous variations
in different parameters, these disturbances were interpreted as propagating acoustic gravity waves (AGWs). The mass-spectrometer
measurements of concentrations of individual atmospheric gases made it possible to determine the following AGW components:
density of the acoustic compression, thermobaric, and average kinetic energies. It has been found out that the average (during
the period) densities of the acoustic and thermobaric energies are approximately equal for polar AGWs. The results indicate
that the contribution of these waves to the energy of the polar upper atmosphere is considerable. 相似文献
5.
Using three radio techniques for determining the spatial and terminal distribution of the electron concentration in the ionospheric
F region, a number of parameters of medium-scale travelling ionospheric disturbances (the effective thickness of the atmospheric
waveguide and height of its axis, spatial and time periods, propagation speeds, and maximum amplitudes of the disturbances)
are determined. 相似文献
6.
Yury V. Fedorenko Tatiana Matveeva Elena Beketova Eystein S. Husebye 《Physics of the Earth and Planetary Interiors》2008,168(3-4):231-236
A long-standing problem in operational seismology is that of reliable focal depth estimation. Standard analyst practice is to pick and identify a ‘phase’ in the P-coda. This picking will always produce a depth estimate but without any validation it cannot be trusted. In this article we ‘hunt’ for standard depth phases like pP, sP and/or PmP but unlike the analyst we use Bayes statistics for classifying the probability that polarization characteristics of pickings belong to one of the mentioned depth phases given preliminary epicenter information. In this regard we describe a general-purpose PC implementation of the Bayesian methodology that can deal with complex nonlinear models in a flexible way. The models are represented by a data-flow diagram that may be manipulated by the analyst through a graphical-programming environment. An analytic signal representation is used with the imaginary part being the Hilbert transform of the signal itself. The pickings are in terms of a plot of posterior probabilities as a function of time for pP, Sp or PmP being within the presumed azimuth and incident angle sectors for given preliminary epicenter locations. We have tested this novel focal depth estimation procedure on explosion and earthquake recordings from Cossack Ranger II stations in Karelia, NW Russia, and with encouraging results. For example, pickings deviating more than 5° off ‘true’ azimuth are rejected while Pn-incident angle estimate exhibit considerable scatter. A comprehensive test of our approach is not quite easy as recordings from so-called Ground Truth events are elusive. 相似文献
7.
P. C. Lightfoot A. J. Naldrett N. S. Gorbachev W. Doherty V. A. Fedorenko 《Contributions to Mineralogy and Petrology》1990,104(6):631-644
The sequence investigated of the Siberian Trap at Noril'sk, USSR, consists of at least 45 flows that have been divided into six lava suites. The lower three suites consist of alkalic to subalkalic basalts (the Ivakinsky suite), overlain by nonporphyritic basalts (the Syverminsky suite), and porphyritic and picritic basalts (the Gudchikhinsky suite). The upper three suites are tholeiitic. The uppermost 750 m of dominantly non-porphyritic basalt belong to the Mokulaevsky suite and are characterized by a nearly constant Mg number (0.54–0.56), SiO2 (48.2–49.1 wt%), Ce (12–18 ppm), and Ce/Yb (5–8). The underlying 1100 m of dominantly porphyritic basalt belong to the Morongovsky and Nadezhdinsky suites. There is a continuous increase in SiO2 (48.1–55.2 wt%), Ce (12–41 ppm), and Ce/Yb (5–18) from the top of the Mokulaevsky to the base of the Nadezhdinsky with little change in the Mg number (0.53–0.59). Mokulaevsky magmas have trace element signatures similar to slightly contaminated transitional type mid-ocean ridge basalts. The change in major and trace element geochemistry in the upper three suites is consistent with a decline in the degree of anatexis and assimilation of tonalitic upper crust by Mokulaevsky magma. The Nadezhdinsky and underlaying lavas thicken within and thus appear to be related to an elongate basin centred on the Noril'sk-Talnakh mining camp. The Mokulaevsky and Morongovsky lavas thicken to the east and appear to be related to a basin centred more than 100 km to the east of the Noril'sk region; these magmas may have risen up out of a different conduit system. 相似文献
8.
O. I. Akhmetov M. I. Beloglazov Yu. V. Fedorenko 《Russian Meteorology and Hydrology》2010,35(5):327-332
According to results of observations at Apatity station in the end of summer-beginning of autumn of the year 2006, investigations
of aeroelectric characteristics of the surface layer of atmosphere for various meteorological conditions are carried out to
find out the spatial structure of atmospheric currents. Horizontal scales of aeroelectric heterogeneities at the wind speed
of 2–6 m/s are evaluated using statistical methods. It is shown that the distribution function of raindrop charges is constant
for one rain cloud during time interval of about 20 min, but can considerably vary from one cloud to another. 相似文献
9.
Pil’gaev S. V. Fedorenko Yu. V. Kleimenova N. G. Manninen J. Nikitenko A. S. Larchenko A. V. Filatov M. V. Lebed’ O. M. Frolov I. E. Kozelov B. V. 《Geomagnetism and Aeronomy》2020,60(2):212-215
Geomagnetism and Aeronomy - The first results are presented for observations of the VLF emissions (1–15 kHz) conducted at polar latitudes during the expedition Transarctica 2019, which was... 相似文献
10.
Nikitenko A. S. Manninen J. Fedorenko Yu. V. Kleimenova N. G. Kuznetsova M. V. Larchenko A. V. Beketova E. B. Pilgaev S. V. 《Geomagnetism and Aeronomy》2022,62(3):209-216
Geomagnetism and Aeronomy - The article presents the results of ground-based observations of very low-frequency (VLF) auroral hiss bursts at the Lovozero (Russia) and Kannuslehto (Finland)... 相似文献