Long-term trends in foF2: their estimating and origin
نویسندگان
چکیده
This paper deals with two problems, methods of foF2 trend determination and origin of trends in foF2, both being controversial in current literature. We found that various regression-based methods and artificial neural networkbased method of Yue et al. (2006) provided comparable results within uncertainties caused mainly by various ways of removing/suppressing the dominant solar cycle effect. The role of geomagnetic activity in the observed trends in foF2 was probably substantial and might be still even rather dominant in the last quarter of the 20th century.
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تاریخ انتشار 2008