Remember Me
Or use your Academic/Social account:


Or use your Academic/Social account:


You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.


Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message


Verify Password:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Apostolov , E. M.; Altadill , D.; Hanbaba , R. (1998)
Publisher: European Geosciences Union
Journal: Annales Geophysicae
Languages: English
Types: Article
Subjects: Geophysics. Cosmic physics, Q, [ SDU.STU ] Sciences of the Universe [physics]/Earth Sciences, [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, Science, Physics, QC1-999, QC801-809
The relative contributions of quasi-periodic oscillations from 2 to 35 days to the variability of foF2 at middle northern latitudes between 42°N and 60°N are investigated. The foF2 hourly data for the whole solar cycle 21 (1976–1986) for four European ionospheric stations Rome (41.9°N, 12.5°E), Poitiers (46.5°N, 0.3°E), Kaliningrad (54.7°N, 20.6°E) and Uppsala (59.8°N, 17.6°E) are used for analysis. The relative contributions of different periodic bands due to planetary wave activity and solar flux variations are evaluated by integrated percent contributions of spectral energy for these bands. The observations suggest that a clearly expressed seasonal variation of percent contributions exists with maximum at summer solstice and minimum at winter solstice for all periodic bands. The contributions for summer increase when the latitude increases. The contributions are modulated by the solar cycle and simultaneously influenced by the long-term geomagnetic activity variations. The greater percentage of spectral energy between 2 to 35 days is contributed by the periodic bands related to the middle atmosphere planetary wave activity.

Key words. Ionosphere · Ionosphere-atmosphere interactions · Mid-latitude ionosphere · Plasma waves and instabilities
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • Altadill, D., On the 18-day quasi-periodic oscillations in the ionosphere, Ann. Geophysicae, 14, 716±724, 1996.
    • Altadill, D., E. M. Apostolov, and L. Alberca., Some seasonal hemispheric similarities in foF2 quasi-2-day oscillations, J. Geophys. Res., 102, 9737±9739, 1997.
    • Apostolov, E. M., and D. Altadill, Ten periodic bands of foF2 quasiperiodic oscillations from 2 to 35 days, Bulg. Geophys. J., 22(3), 20±24, 1996.
    • Apostolov, E. M., L. Alberca, and D. Altadill, Solar cycle and seasonal behaviour of quasi-two and ®ve-day oscillations in the time variations of foF2, Ann. Geo®sica, 37(2), 187±192, 1994.
    • Apostolov, E. M., D. Altadill, and L. Alberca, Characteristics of quasi-2-day oscillations in the foF2 at northern middle latitudes, J. Geophys. Res., 100, 12163±12171, 1995.
    • Chen, P. R., Two-day oscillation of the equatorial ionization anomaly, J. Geophys. Res., 97, 6343±6357, 1992.
    • Forbes, J. M., and S. Leveroni, Quasi 16-day oscillation in the ionosphere, Geophys. Res. Lett., 19, 981±984, 1992.
    • Forbes, J. M., R. Gu€ee, X. Zhang, D. Fritts, D. Riggin, A. Manson, C. Meek, and R. A. Vincent, Quasi 2-day oscillation of the ionosphere during summer 1992, J. Geophys. Res., 102, 7301±7305, 1997.
    • Fraser, G. J., The 5-day wave and ionospheric absorption, J. Atmos. Terr. Phys., 39, 121±124, 1977.
    • Ito, R., S. Kato, and T. Tsuda, Consideration of an ionospheric wind dynamo driven by a planetary wave with a two-day period, J. Atmos. Terr. Phys., 48, 1±13, 1986.
    • Lastovicka, J., and P. Mlch, Solar cycle e€ect on oscillations in the period range of 2±20 days in the F region of the ionosphere, Ann. Geo®sica, 39(4), 783±790, 1996.
    • Mikhailov, A. V., Possible mechanism for in-phase variation of electron concentration in the ionospheric regions E and F2 (in Russian), Geomagn. Aeron., 23, 557±561, 1983.
    • Pancheva, D., Travelling quasi-two-day ¯uctuations in the summer F-region, C. R. Acad. Bulg. Sci., 41(11), 41±44, 1988.
    • Pancheva, D., and I. Lysenko, Quasi-two-day ¯uctuations observed in the summer F region electron maximum, Bulg. Geophys. J., 14(2), 41±51, 1988.
    • Pancheva, D., L. Alberca, and B. de la Morena, Simultaneous observation of the quasi-two-day variations in the lower and upper ionosphere over Europe, J. Atmos. Terr. Phys., 56, 43±50, 1994.
    • Parish, H. F., J. M. Forbes, and F. Kamalabadi, Planetary wave and solar emission signatures in the equatorial electrojet, J. Geophys. Res., 99, 355±368, 1994.
    • Salby, M. L., Survey of planetary scale travelling waves: the state of theory and observations, Rev. Geophys. Space Phys., 22, 209± 236, 1984.
    • Vitinsky, Y. I., M. Kopecky, and G. V. Kuklin, Statistics of sunspotcreating activity (in Russian), Nauka, Moscow, 1986.
  • No related research data.
  • No similar publications.