Results 1 to 10 of about 819 (150)
Study of mid-latitude nighttime enhancement in F-region electron density using tomographic images over the UK [PDF]
Annales Geophysicae, 2003 Nighttime enhancements in ionospheric electron content (IEC)/peak electron density (NmF2) have been studied by various workers in the equatorial anomaly and mid-latitude regions.
R. S. Dabas, L. Kersley
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Solar Cycle variations of ƒoF2 from IGY to 1990 [PDF]
Annales Geophysicae, 2002 Noontime monthly median values of F2-layer critical frequency foF2 (m) for some ionospheric stations representing low- and mid-latitudes are examined for their dependence on solar activity for the years 1957 (IGY) to 1990.
N. K. Sethi +3 more
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Global morphology of night-time NmF2 enhancements [PDF]
Annales Geophysicae, 2002 An overall statistical study of night-time enhancements of NmF2 has been carried out. All available foF2 observations since 1955 at 53 ionosonde stations distributed worldwide in the latitude range fgeom = 15° - 60° were used in the analysis ...
A. F. Farelo +3 more
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The structure of mid- and high-latitude ionosphere during September 1999 storm event obtained from GPS observations [PDF]
Annales Geophysicae, 2002 TEC data, obtained from over 60 GPS stations, were used to study the ionospheric effects of the 12–16 September 1999 magnetic storm over Europe. The spatial and temporal changes of the ionosphere were analysed as a time series of TEC maps, which ...
I. I. Shagimuratov +4 more
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Daytime electron density at the F1-region in Europe during geomagnetic storms [PDF]
Annales Geophysicae, 2002 This study attempts to demonstrate changes in the ionospheric F1-region daytime ionization during geomagnetic storms. The F1-region is explored using available data from several European middle latitude and lower latitude observatories and a set of
D. Buresova +4 more
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On the spectrum of mid-latitude sporadic-E irregularities [PDF]
Annales Geophysicae, 2000 We discuss the creation of mid-latitude sporadic-E plasma irregularities (with length-scales smaller than sporadic layer thickness) by the neutral atmosphere turbulence.
Yu. V. Kyzyurov
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Mid-latitude ionosphere during two great geomagnetic storms
Annals of Geophysics, 1996 The ionospheric disturbances observed at many European ionosonde stations in association with the severe geomagnetic storms occurring on 19-20 December 1980 and 11-12 April 1981 were investigated by using the available ionospheric and geomagnetic data ...
L. R. Cander, I. M. Vasiljevic
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Letter to the Editor: Spatial and seasonal variations of the foF2 long-term trends [PDF]
Annales Geophysicae, 1999 Using a method suggested by the authors earlier, the long-term trends of the F2-layer critical frequency, foF2 are derived for a set of ionospheric stations with a wide latitudinal and longitudinal coverage. All the trends are found to be negative.
A. D. Danilov +2 more
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Journal of Space Weather and Space Climate, 2019 The Empirical Canadian High Arctic Ionospheric Model (E-CHAIM) is a new empirical model of high latitude ionospheric electron density. While the introductory studies regarding E-CHAIM include validations, E-CHAIM’s topside model was notably excluded from
Themens David R. +2 more
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The ionospheric responses to the 11 August 1999 solar eclipse: observations and modeling [PDF]
Annales Geophysicae, 2008 A total eclipse occurred on 11 August 1999 with its path of totality passing over central Europe in the latitude range 40°–50° N. The ionospheric responses to this eclipse were measured by a wide ionosonde network.
H. Le +5 more
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