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11.
Having applied the method of discriminant analysis to the TOMS data of satellite sounding of the total ozone content (TOC) in the March months of 1979–2008, the authors could make a new estimate of the TOC field variability in the Northern Hemisphere and interlongitudinal regularities of its changes under the action of climatic variability. The effects of temperature variations in the polar stratosphere, El Niño, and quasi-biennial oscillation (QBO) have proven comparable and reach 80 DU in some regions. The influence of the Arctic Oscillation (AO) reaches 40 DU. The regions of TOC variations and their location and dimensions change depending on the phases of QBO, AO, and El Niño-Southern Oscillation (ENSO). Three regions of increased TOC—over Europe, Eastern Siberia, and the Pacific Ocean—are formed in years with a warm stratosphere. A compensating TOC decrease takes place in the tropics and over Greenland. In the years of El Niño and the easterly QBO phase, the TOC increases over Europe and drops over the central Pacific, as well as to the south from 45° N. The AO controls the ozone growth over most of Eurasia at temperate latitudes and its weak drop over the Atlantic. It was impossible to obtain such quantitative estimates with the use of methods based on an independent analysis of the TOC series at individual points of the coordinate grid. Testing with the Monte Carlo method confirmed that the results obtained are significant with a probability of 95–99.9%.  相似文献   
12.
A model for fast sequential disintegration of meteoroids in the terrestrial atmosphere, which takes a scale factor into account, was published by Ivanov and Ryzhanskii (1997). The trajectory of a nonablating body was determined by stage-by-stage computations; the number of stages could be more than 30. In the present study, this physical model is represented by a set of differential equations, which are solved by the method of separation of variables, in particular, with allowance for ablation. For bounded values of the mass-loss parameter, the solution is expressed in terms of elementary functions. Examples of the calculation of meteoric-body trajectories based on other models and their comparison with the proposed model are presented. Comparison of the results indicate the efficiency of these models in solving the inverse problems of dynamics and disruption of meteoroids in the atmosphere.  相似文献   
13.
This paper presents the results of simultaneous observations of narrow-band noise VLF emissions in the frequency range 4–10 kHz at Kannuslehto ground station in Northern Finland and by Van Allen Probes (previously RBSP) in the equatorial part of the magnetosphere. The event of December 25, 2015, is considered. During the event, narrow-band noise VLF emissions were detected on the Earth in two frequency ranges, f = 3.5–6 kHz and f = 8–10 kHz, between 1100 and 1300 UT. Narrow-band VLF emissions in the equatorial zone were also observed during that time by the RBSP-B satellite; their frequency was close to the electron equatorial half-gyrofrequency and gradually increased from 3 to 11 kHz during the satellite motion from L = 5.0 to L = 3.0. Analysis of the fine structure of the emissions on the ground showed that their spectral and temporal characteristics corresponded to emissions by the satellites in localized zones at different L-shells. The ground-based observations at lower frequencies correlated with the satellite observations at larger L-shells. In order to localize the regions of the generation of the VLF emissions observed at Kannuslehto auroral station at different frequencies, we calculated the ray trajectories of waves from the equator for the plasma density distributions detected by Van Allen Probes. The calculations of the trajectories showed that the VLF waves detected at Kannuslehto station could travel to the ground only if they propagated in the large-scale density ducts (700–900 km) observed by Van Allen Probes.  相似文献   
14.
A simulation system which models the dynamics of major groups of plankton in the Okhotsk Sea, taking into account the most important abiotic environmental factors and the complex of external influence, is devised. A model study of the seasonal variability and spatial distribution of these groups has been carried out. The simulation complex consists of blocks which represent complete program algorithms of separate processes: the large-scale water circulation in the Okhotsk Sea, the formation of salinity, temperature conditions, spatial-temporal dynamics of phytoplankton, and the dynamics of macroplankton and mesoplankton.Translated by M. M. Trufanov.  相似文献   
15.
Specific type of energetic electron precipitation accompanied by a sharp increase in trapped energetic electron flux are found in the data obtained from low-altitude NOAA satellites. These strongly localized variations of the trapped and precipitated energetic electron flux have been observed in the evening sector near the plasmapause during recovery phase of magnetic storms. Statistical characteristics of these structures as well as the results of comparison with proton precipitation are described. We demonstrate the spatial coincidence of localized electron precipitation with cold plasma gradient and whistler wave intensification measured on board the DE-1 and Aureol-3 satellites. A simultaneous localized sharp increase in both trapped and precipitating electron flux could be a result of significant pitch-angle isotropization of drifting electrons due to their interaction via cyclotron instability with the region of sharp increase in background plasma density.  相似文献   
16.
Geomagnetism and Aeronomy - The ionospheric disturbances detected during large earthquake over the region of Haiti on January 12, 2010 on the base the analysis of data GPS-observations are...  相似文献   
17.
Summary The elements of the VLF chorus, observed simultaneously at a ground station and satellite in polar orbit, can be used to determine the differences in the arrival times of waves and their dependence on latitude. Mostly does not change practically over a wide range of latitudes, however, in some cases it may increase appreciably at low value of L. Model computations of the propagation time, based on the assumption that the source of the chorus is located close to the equatorial plane, have indicated the possibility of explaining the increase in at low latitudes by the presence of a step in the electron density profile close to this plane.
a¶rt;u m a u a um nmu nun um nm n¶rt;um amu u nu¶rt;a ma a u u um auum (L). um a a m ¶rt;uana um, m a a¶rt;am aum uu a a L-a. am anmau n¶rt;nuu amua umua naam m um uu a uu uma auu mnu an¶rt;uu m mauu amua nmu.
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18.
auuau uu muna a f>1,5 , aumua ¶rt; a nmua uu m u a ¶rt; a mau. mu a aum nm uu, umu a mauu aa (L=2,1) n¶rt; nm uu (L=5). m mmmum mu umua uu, umu a mu mau. au uu a nm m, m a um nmam a 2000–3000 u anu u a L=2,2–5,9. au mmmu nma aamumu a u nmu uu a¶rt;am u amu aua uu a L 3,5. aa, m a mauu aa u ¶rt;a a¶rt; nuu uu a , umum uuu n¶rt; a¶rt;a a nmu. au a n¶rt;num, m am a L 3,5,¶rt; aam au uu u au mmu nma aamumu a u nmu uu, aa ¶rt;amua anau a nana. m u m amu mm au anum u ¶rt; ¶rt;a ua n¶rt;u anmau u ¶rt; — ua.  相似文献   
19.
LHR whistlers     
Summary A type of whistler with unusual dispersion near the LHR frequency has been found, in a number of VLF experiments aboard low-orbiting Intercosmos satellites. These “LHR whistlers” are thought to be the result of transformation of the common whistler mode waves into quasi-electrostatic waves, as they propagate near the LHR frequency. The mechanism generating the LHR whistlers for downgoing whistler waves is discussed. It is shown how the characteristic features of the LHR whistlers reflect the dynamic changes in the outer ionosphere at midlatitudes.
Резюме В ря?rt;е ОНЧ эксnерuменmов, выnолненых нa нuзколеmящuх сnуmнuкaх серuu „Инmеркосмос“, был нaŭ?rt;ен mun свuсmов с необычноŭ ?rt;uсnерсuеŭ вблuзu чaсmоmы нuжне?rt;о ?rt;uбрu?rt;но?rt;о резонaнсa (НГР). Эmu „НГР свuсmы“ рaссмamрuвaюmся кaк резульmam mрaнсформaцuu обычных свuсmовых волн в квaзuэлекmросmamuческuе волны в nроцессе рaсnросmрaненuя вблuзu чaсmоmы НГР. Обсуж?rt;aеmся мехaнuзм вознuкновенuя НГР свuсmов ?rt;ля свuсmовых волн, рaсnросmрaняющuхся оm большuх высоm к Земле. Покaзaно, кaкuм обрaзом хaрaкmерные особенносmu НГР свuсmов оmрaжaюm ?rt;uнaмuческuе uзмененuя во внещнеŭ uоносфере сре?rt;нuх шuроm.
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20.
Nemirovskaya  I. A.  Titova  A. M. 《Oceanology》2019,59(4):504-513
Oceanology - The article presents the results of studies on the grain size distribution of aerosols and surface waters (cruise 31 of the R/V Akademik Nikolay Strakhov in December 2015–January...  相似文献   
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