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文件名称：Variation of E - layer critical frequency with solar activity
文件大小：324KB
文件格式：PDF
更新时间：2017-05-20 11:15:43
E - layer critical frequency
Ionospheric foE data over one or, where available, two solar
cycles from 47 stations all over the world are correlated with
the corresponding data of each of the three solar indices, the
Zurich relative sunspot number R, the solar radio noise flux $
at 10-7 cm and the ionospheric index of solar activity IF2, and
numerical expressions are derived. There is no difference in the
degree of correlation between the variates of each of the above
expressions at the 5% level. At each station, the monthly values
of the sensitivity to solar activity changes are independent of
season and their 12-month average is independent of the latitude
of the station. The uncertainty in the relations is mainly due to
inconsistency between solar-cycle variations of f0E at different
stations, but/? appears less reliable than the other two parameters