Solar Cycle variations of ƒ<i>o</i>F2 from IGY to 1990
Noontime monthly median values of F2-layer critical frequency <i>f</i>oF2 (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. This is the period for which ionospheric data in d...
Main Authors: | , , |
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Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2002-10-01
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Series: | Annales Geophysicae |
Online Access: | https://www.ann-geophys.net/20/1677/2002/angeo-20-1677-2002.pdf |
Summary: | Noontime monthly median values of F2-layer
critical frequency <i>f</i>oF2 (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. This is the period for which ionospheric data in
digital form is available in two CD-ROMs at the World Data Center, Boulder. It
is observed that at mid-latitudes, <i>f</i>oF2 (m) shows nearly a linear
relationship with R12 (the 12-month running average of the Zurich sunspot
number), though this relation is nonlinear for low-latitudes. These results
indicate some departures from the existing information often used in
theoretical and applied areas of space research.<br><br><b>Key words.</b> Ionosphere (equatorial ionosphere;
mid-latitude ionosphere; modelling and forecasting) |
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ISSN: | 0992-7689 1432-0576 |