The ionospheric foF2 data over Istanbul and their response to solar activity for the years 1964-1969 and 1993

Date

1998-01-01

Author

Ozguc, A
Atac, T
Tulunay, Yurdanur
Stanislawska, I

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A Polish-made vertical ionosonde (VI) has been operated at the Kandilli Observatory in Istanbul, for almost one year (May 1993 - April 1994) as part of the COST 238, PRIME Project. The critical frequencies were obtained for every half-hour interval. The data obtained during this campaign, on the descending branch of solar cycle 22, and the data measured earlier in Istanbul for cycle 20 were analysed and the characteristic behaviour of the F2 region ionosphere over Istanbul has been determined. This is a unique data set for this area. Several markers of the solar cycle activities in terms of the daily relative sunspot numbers, F10.7 cm solar radio flux and solar flare index, and the magnetic daily index of Ap were then used to seek the possible influence of the solar and ionospheric activities on the critical frequencies observed in Istanbul. It was found that the solar flare index, as a solar activity index, was more reliable in determining quiet ionospheric days. it is shown that the minimum and maximum time values of the solar activity are more convenient for ionospheric prediction and modelling.

Subject Keywords

Geochemistry and Petrology, Geophysics

URI

https://hdl.handle.net/11511/51610

Journal

STUDIA GEOPHYSICA ET GEODAETICA

DOI

https://doi.org/10.1023/a:1023348802826

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

A. Ozguc, T. Atac, Y. Tulunay, and I. Stanislawska, “The ionospheric foF2 data over Istanbul and their response to solar activity for the years 1964-1969 and 1993,” STUDIA GEOPHYSICA ET GEODAETICA, pp. 112–118, 1998, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51610.