Long-term trends in foF2 over Moscow ionosonde station: Its estimate and origins
نویسندگان
چکیده
منابع مشابه
Long-term trends in foF2: their estimating and origin
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. T...
متن کاملLong-term trends in the relation between daytime and nighttime values of foF2
The data from the vertical ionospheric sounding for 12 stations over the world were analyzed to find the relation between the values of foF2 for 02:00 LT and 14:00 LT of the same day. It is found that, in general, there exists a negative correlation between foF2(02) and foF2(14). The value of the correlation coefficient R(foF2) can be in some cases high enough and reach minus 0.7–0.8. The value...
متن کاملLetter to the editor Spatial and seasonal variations of the foF2 long-term trends
Using a method suggested by the authors earlier, the long-term trends of the F2-layer critical frequency, foF2 are derived for a set of ionospheric stations with a wide latitudinal and longitudinal coverage. All the trends are found to be negative. A pronounced dependence on geomagnetic latitude is found, the trend magnitude increasing with the latter. No globe scale longitudinal eect in trend...
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15 صفحه اولLong-term hmF2 trends in the Eurasian longitudinal sector from the ground-based ionosonde observations
The method earlier used for the foF2 long-term trends analysis is applied to reveal hmF2 long-term trends at 27 ionosonde stations in the European and Asian longitudinal sectors. Observed M(3000)F2 data for the last 3 solar cycles are used to derive hmF2 trends. The majority of the studied stations show significant hmF2 linear trends with a confidence level of at least 95% for the period after ...
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ژورنال
عنوان ژورنال: Chinese Science Bulletin
سال: 2012
ISSN: 1001-6538,1861-9541
DOI: 10.1007/s11434-012-5046-x